Render pass API. Replaces love.graphics.setCanvas and friends.

- Removed love.graphics.set/getCanvas, Canvas:renderTo, Canvas:newImageData, love.graphics.clear, love.graphics.discard, and love.graphics.newScreenshot.

- Added love.graphics.beginPass and love.graphics.endPass. All rendering must happen within a pass. love.draw is now called while a render pass to the main screen is active.
- Added love.graphics.renderPass, which is a wrapper for begin/endPass which calls the supplied function argument in between a begin/end. This is similar to the old Canvas:renderTo.
- Added love.graphics.isPassActive, getPassCanvases, getPassWidth, getPassHeight, and getPassDimensions.
- Added love.graphics.captureScreenshot.

- Added a new love.run callback love.drawpasses, which is called after love.update and before love.draw. It is the place to render to Canvases using beginPass or renderPass, since love.draw now always draws to the main screen.

- Renamed the ‘canvasswitches’ field in the table returned by love.graphics.getStats to ‘renderpasses’.

love.graphics.beginPass has the following variants (and renderPass mirrors them with an additional function argument at the end):

- love.graphics.beginPass(), begins rendering to the main screen without clearing it.
- love.graphics.beginPass(r, g, b [, a]), begins rendering to the main screen and clears the screen to the specified color.

- love.graphics.beginPass(canvas [, willstencil]), begins rendering to the specified Canvas without clearing it. love.graphics.stencil can only be used within the Canvas if ‘willstencil’ is true.
- love.graphics.beginPass(canvas, r, g, b [, a] [, willstencil]), beings rendering to the specified Canvas and clears it to the specified color. love.graphics.stencil can only be used within the Canvas if ‘willstencil’ is true.

- love.graphics.beginPass(info), where ‘info’ is a table in the following form:
{
    {canvas [, r, g, b, a]}, — A canvas and an optional color to clear the Canvas to when the pass begins.
    {canvas2, [r, g, b, a]}, — Additional Canvases and optional clear colors for multi-canvas rendering.
    …,
    stencil = false, — Optional boolean field to specify whether love.graphics.stencil is allowed within this pass. False by default.
}

The pass info table can be created once up-front and used for multiple beginPass/renderPass calls.

love.graphics.endPass can take an optional callback function argument, which causes endPass to capture the contents of the Canvas drawn to in the render pass to a new ImageData and passes it to the supplied function (this replaces Canvas:newImageData). This does not work on the main screen.

love.graphics.captureScreenshot replaces love.graphics.newScreenshot. It takes a callback function argument which causes love.graphics.present to capture the contents of the screen to a new ImageData and passes it to the supplied function. captureScreenshot can only be called before drawing to the main screen begins in the current frame (e.g. in love.keypressed, love.update, etc.)

--HG--
branch : minor

CMakeLists.txt

@@ -1418,6 +1418,17 @@ set(LOVE_SRC_3P_WUFF
 
 add_library(love_3p_wuff ${LOVE_SRC_3P_WUFF})
 
+#
+# xxHash
+#
+
+set(LOVE_SRC_3P_XXHASH
+	src/libraries/xxHash/xxhash.c
+	src/libraries/xxHash/xxhash.h
+)
+
+add_library(love_3p_xxhash ${LOVE_SRC_3P_XXHASH})
+
 set(LOVE_3P
 	love_3p_box2d
 	love_3p_ddsparse
@@ -1429,6 +1440,7 @@ set(LOVE_3P
 	love_3p_lz4
 	love_3p_noise1234
 	love_3p_wuff
+	love_3p_xxhash
 )
 
 love_disable_warnings(love_3p_box2d love_3p_enet love_3p_luasocket)

platform/xcode/liblove.xcodeproj/project.pbxproj

@@ -880,6 +880,9 @@
 		FA4943551D9DDFFE00E8D38A /* HashFunction.cpp in Sources */ = {isa = PBXBuildFile; fileRef = FA1DC2611C5D9555008F99A0 /* HashFunction.cpp */; };
 		FA4B66C91ABBCF1900558F15 /* Timer.cpp in Sources */ = {isa = PBXBuildFile; fileRef = FA4B66C81ABBCF1900558F15 /* Timer.cpp */; };
 		FA4B66CA1ABBCF1900558F15 /* Timer.cpp in Sources */ = {isa = PBXBuildFile; fileRef = FA4B66C81ABBCF1900558F15 /* Timer.cpp */; };
+		FA4F2B791DE0125B00CA37D7 /* xxhash.c in Sources */ = {isa = PBXBuildFile; fileRef = FA4F2B771DE0125B00CA37D7 /* xxhash.c */; };
+		FA4F2B7A1DE0125B00CA37D7 /* xxhash.h in Headers */ = {isa = PBXBuildFile; fileRef = FA4F2B781DE0125B00CA37D7 /* xxhash.h */; };
+		FA4F2B7B1DE0181B00CA37D7 /* xxhash.c in Sources */ = {isa = PBXBuildFile; fileRef = FA4F2B771DE0125B00CA37D7 /* xxhash.c */; };
 		FA56D9BC1C208A0200D8D3C7 /* libmodplug.a in Frameworks */ = {isa = PBXBuildFile; fileRef = FA56D9BA1C2089EE00D8D3C7 /* libmodplug.a */; };
 		FA577AB016C7507900860150 /* Cocoa.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = FA577A7916C71A1700860150 /* Cocoa.framework */; };
 		FA577AC216C7512D00860150 /* FreeType.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = FA577A6716C719D900860150 /* FreeType.framework */; };
@@ -1575,6 +1578,8 @@
 		FA41A3C61C0A1F950084430C /* ASTCHandler.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = ASTCHandler.cpp; sourceTree = "<group>"; };
 		FA41A3C71C0A1F950084430C /* ASTCHandler.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTCHandler.h; sourceTree = "<group>"; };
 		FA4B66C81ABBCF1900558F15 /* Timer.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = Timer.cpp; sourceTree = "<group>"; };
+		FA4F2B771DE0125B00CA37D7 /* xxhash.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = xxhash.c; sourceTree = "<group>"; };
+		FA4F2B781DE0125B00CA37D7 /* xxhash.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = xxhash.h; sourceTree = "<group>"; };
 		FA56D9BA1C2089EE00D8D3C7 /* libmodplug.a */ = {isa = PBXFileReference; lastKnownFileType = archive.ar; path = libmodplug.a; sourceTree = "<group>"; };
 		FA577A6716C719D900860150 /* FreeType.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = FreeType.framework; path = /Library/Frameworks/FreeType.framework; sourceTree = "<absolute>"; };
 		FA577A6D16C719EA00860150 /* Lua.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Lua.framework; path = /Library/Frameworks/Lua.framework; sourceTree = "<absolute>"; };
@@ -1783,6 +1788,7 @@
 				FA1557BE1CE90A2C00AFF582 /* tinyexr */,
 				FA0B7A191A958EA3000E1D17 /* utf8 */,
 				FA0B7A1F1A958EA3000E1D17 /* Wuff */,
+				FA4F2B761DE0125B00CA37D7 /* xxHash */,
 			);
 			name = libraries;
 			path = ../../src/libraries;
@@ -2890,6 +2896,15 @@
 			path = theora;
 			sourceTree = "<group>";
 		};
+		FA4F2B761DE0125B00CA37D7 /* xxHash */ = {
+			isa = PBXGroup;
+			children = (
+				FA4F2B771DE0125B00CA37D7 /* xxhash.c */,
+				FA4F2B781DE0125B00CA37D7 /* xxhash.h */,
+			);
+			path = xxHash;
+			sourceTree = "<group>";
+		};
 		FA56D9B91C2089CE00D8D3C7 /* modplug */ = {
 			isa = PBXGroup;
 			children = (
@@ -3286,6 +3301,7 @@
 				FA0B7E5C1A95902C000E1D17 /* wrap_MotorJoint.h in Headers */,
 				FA0B7A7C1A958EA3000E1D17 /* b2Contact.h in Headers */,
 				FA0B7A881A958EA3000E1D17 /* b2PolygonAndCircleContact.h in Headers */,
+				FA4F2B7A1DE0125B00CA37D7 /* xxhash.h in Headers */,
 				FA0B7DDE1A95902C000E1D17 /* wrap_BezierCurve.h in Headers */,
 				FA0B7DED1A95902C000E1D17 /* Cursor.h in Headers */,
 				FA0B7E501A95902C000E1D17 /* wrap_Fixture.h in Headers */,
@@ -3567,6 +3583,7 @@
 				FA0B7CD41A95902C000E1D17 /* Source.cpp in Sources */,
 				FAA3A9AF1B7D465A00CED060 /* android.cpp in Sources */,
 				FA0B7CD11A95902C000E1D17 /* Audio.cpp in Sources */,
+				FA4F2B7B1DE0181B00CA37D7 /* xxhash.c in Sources */,
 				FA0B7D131A95902C000E1D17 /* Font.cpp in Sources */,
 				FA0B7EC91A95902C000E1D17 /* threads.cpp in Sources */,
 				FA0B7A781A958EA3000E1D17 /* b2CircleContact.cpp in Sources */,
@@ -3894,6 +3911,7 @@
 				FA0B7DA51A95902C000E1D17 /* PNGHandler.cpp in Sources */,
 				FA0B7B371A958EA3000E1D17 /* wuff_internal.c in Sources */,
 				FA0B7E971A95902C000E1D17 /* Sound.cpp in Sources */,
+				FA4F2B791DE0125B00CA37D7 /* xxhash.c in Sources */,
 				FA0B7E361A95902C000E1D17 /* WheelJoint.cpp in Sources */,
 				FA0B7A471A958EA3000E1D17 /* b2PolygonShape.cpp in Sources */,
 				FA0B7D8D1A95902C000E1D17 /* ddsHandler.cpp in Sources */,

src/libraries/xxHash/xxhash.c

@@ -0,0 +1,889 @@
+/*
+*  xxHash - Fast Hash algorithm
+*  Copyright (C) 2012-2016, Yann Collet
+*
+*  BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+*
+*  Redistribution and use in source and binary forms, with or without
+*  modification, are permitted provided that the following conditions are
+*  met:
+*
+*  * Redistributions of source code must retain the above copyright
+*  notice, this list of conditions and the following disclaimer.
+*  * Redistributions in binary form must reproduce the above
+*  copyright notice, this list of conditions and the following disclaimer
+*  in the documentation and/or other materials provided with the
+*  distribution.
+*
+*  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+*  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+*  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+*  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+*  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+*  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+*  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+*  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+*  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+*  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+*  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*
+*  You can contact the author at :
+*  - xxHash homepage: http://www.xxhash.com
+*  - xxHash source repository : https://github.com/Cyan4973/xxHash
+*/
+
+
+/* *************************************
+*  Tuning parameters
+***************************************/
+/*!XXH_FORCE_MEMORY_ACCESS :
+ * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
+ * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
+ * The below switch allow to select different access method for improved performance.
+ * Method 0 (default) : use `memcpy()`. Safe and portable.
+ * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
+ *            This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
+ * Method 2 : direct access. This method doesn't depend on compiler but violate C standard.
+ *            It can generate buggy code on targets which do not support unaligned memory accesses.
+ *            But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
+ * See http://stackoverflow.com/a/32095106/646947 for details.
+ * Prefer these methods in priority order (0 > 1 > 2)
+ */
+#ifndef XXH_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
+#  if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
+#    define XXH_FORCE_MEMORY_ACCESS 2
+#  elif defined(__INTEL_COMPILER) || \
+  (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) ))
+#    define XXH_FORCE_MEMORY_ACCESS 1
+#  endif
+#endif
+
+/*!XXH_ACCEPT_NULL_INPUT_POINTER :
+ * If the input pointer is a null pointer, xxHash default behavior is to trigger a memory access error, since it is a bad pointer.
+ * When this option is enabled, xxHash output for null input pointers will be the same as a null-length input.
+ * By default, this option is disabled. To enable it, uncomment below define :
+ */
+/* #define XXH_ACCEPT_NULL_INPUT_POINTER 1 */
+
+/*!XXH_FORCE_NATIVE_FORMAT :
+ * By default, xxHash library provides endian-independent Hash values, based on little-endian convention.
+ * Results are therefore identical for little-endian and big-endian CPU.
+ * This comes at a performance cost for big-endian CPU, since some swapping is required to emulate little-endian format.
+ * Should endian-independence be of no importance for your application, you may set the #define below to 1,
+ * to improve speed for Big-endian CPU.
+ * This option has no impact on Little_Endian CPU.
+ */
+#ifndef XXH_FORCE_NATIVE_FORMAT   /* can be defined externally */
+#  define XXH_FORCE_NATIVE_FORMAT 0
+#endif
+
+/*!XXH_FORCE_ALIGN_CHECK :
+ * This is a minor performance trick, only useful with lots of very small keys.
+ * It means : check for aligned/unaligned input.
+ * The check costs one initial branch per hash; set to 0 when the input data
+ * is guaranteed to be aligned.
+ */
+#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */
+#  if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
+#    define XXH_FORCE_ALIGN_CHECK 0
+#  else
+#    define XXH_FORCE_ALIGN_CHECK 1
+#  endif
+#endif
+
+
+/* *************************************
+*  Includes & Memory related functions
+***************************************/
+/*! Modify the local functions below should you wish to use some other memory routines
+*   for malloc(), free() */
+#include <stdlib.h>
+static void* XXH_malloc(size_t s) { return malloc(s); }
+static void  XXH_free  (void* p)  { free(p); }
+/*! and for memcpy() */
+#include <string.h>
+static void* XXH_memcpy(void* dest, const void* src, size_t size) { return memcpy(dest,src,size); }
+
+#define XXH_STATIC_LINKING_ONLY
+#include "xxhash.h"
+
+
+/* *************************************
+*  Compiler Specific Options
+***************************************/
+#ifdef _MSC_VER    /* Visual Studio */
+#  pragma warning(disable : 4127)      /* disable: C4127: conditional expression is constant */
+#  define FORCE_INLINE static __forceinline
+#else
+#  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
+#    ifdef __GNUC__
+#      define FORCE_INLINE static inline __attribute__((always_inline))
+#    else
+#      define FORCE_INLINE static inline
+#    endif
+#  else
+#    define FORCE_INLINE static
+#  endif /* __STDC_VERSION__ */
+#endif
+
+
+/* *************************************
+*  Basic Types
+***************************************/
+#ifndef MEM_MODULE
+# if !defined (__VMS) && (defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
+#   include <stdint.h>
+    typedef uint8_t  BYTE;
+    typedef uint16_t U16;
+    typedef uint32_t U32;
+    typedef  int32_t S32;
+# else
+    typedef unsigned char      BYTE;
+    typedef unsigned short     U16;
+    typedef unsigned int       U32;
+    typedef   signed int       S32;
+# endif
+#endif
+
+#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
+
+/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
+static U32 XXH_read32(const void* memPtr) { return *(const U32*) memPtr; }
+
+#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
+
+/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
+/* currently only defined for gcc and icc */
+typedef union { U32 u32; } __attribute__((packed)) unalign;
+static U32 XXH_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
+
+#else
+
+/* portable and safe solution. Generally efficient.
+ * see : http://stackoverflow.com/a/32095106/646947
+ */
+static U32 XXH_read32(const void* memPtr)
+{
+    U32 val;
+    memcpy(&val, memPtr, sizeof(val));
+    return val;
+}
+
+#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
+
+
+/* ****************************************
+*  Compiler-specific Functions and Macros
+******************************************/
+#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+
+/* Note : although _rotl exists for minGW (GCC under windows), performance seems poor */
+#if defined(_MSC_VER)
+#  define XXH_rotl32(x,r) _rotl(x,r)
+#  define XXH_rotl64(x,r) _rotl64(x,r)
+#else
+#  define XXH_rotl32(x,r) ((x << r) | (x >> (32 - r)))
+#  define XXH_rotl64(x,r) ((x << r) | (x >> (64 - r)))
+#endif
+
+#if defined(_MSC_VER)     /* Visual Studio */
+#  define XXH_swap32 _byteswap_ulong
+#elif XXH_GCC_VERSION >= 403
+#  define XXH_swap32 __builtin_bswap32
+#else
+static U32 XXH_swap32 (U32 x)
+{
+    return  ((x << 24) & 0xff000000 ) |
+            ((x <<  8) & 0x00ff0000 ) |
+            ((x >>  8) & 0x0000ff00 ) |
+            ((x >> 24) & 0x000000ff );
+}
+#endif
+
+
+/* *************************************
+*  Architecture Macros
+***************************************/
+typedef enum { XXH_bigEndian=0, XXH_littleEndian=1 } XXH_endianess;
+
+/* XXH_CPU_LITTLE_ENDIAN can be defined externally, for example on the compiler command line */
+#ifndef XXH_CPU_LITTLE_ENDIAN
+    static const int g_one = 1;
+#   define XXH_CPU_LITTLE_ENDIAN   (*(const char*)(&g_one))
+#endif
+
+
+/* ***************************
+*  Memory reads
+*****************************/
+typedef enum { XXH_aligned, XXH_unaligned } XXH_alignment;
+
+FORCE_INLINE U32 XXH_readLE32_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
+{
+    if (align==XXH_unaligned)
+        return endian==XXH_littleEndian ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr));
+    else
+        return endian==XXH_littleEndian ? *(const U32*)ptr : XXH_swap32(*(const U32*)ptr);
+}
+
+FORCE_INLINE U32 XXH_readLE32(const void* ptr, XXH_endianess endian)
+{
+    return XXH_readLE32_align(ptr, endian, XXH_unaligned);
+}
+
+static U32 XXH_readBE32(const void* ptr)
+{
+    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr);
+}
+
+
+/* *************************************
+*  Macros
+***************************************/
+#define XXH_STATIC_ASSERT(c)   { enum { XXH_static_assert = 1/(int)(!!(c)) }; }    /* use only *after* variable declarations */
+XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
+
+
+/* *******************************************************************
+*  32-bits hash functions
+*********************************************************************/
+static const U32 PRIME32_1 = 2654435761U;
+static const U32 PRIME32_2 = 2246822519U;
+static const U32 PRIME32_3 = 3266489917U;
+static const U32 PRIME32_4 =  668265263U;
+static const U32 PRIME32_5 =  374761393U;
+
+static U32 XXH32_round(U32 seed, U32 input)
+{
+    seed += input * PRIME32_2;
+    seed  = XXH_rotl32(seed, 13);
+    seed *= PRIME32_1;
+    return seed;
+}
+
+FORCE_INLINE U32 XXH32_endian_align(const void* input, size_t len, U32 seed, XXH_endianess endian, XXH_alignment align)
+{
+    const BYTE* p = (const BYTE*)input;
+    const BYTE* bEnd = p + len;
+    U32 h32;
+#define XXH_get32bits(p) XXH_readLE32_align(p, endian, align)
+
+#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
+    if (p==NULL) {
+        len=0;
+        bEnd=p=(const BYTE*)(size_t)16;
+    }
+#endif
+
+    if (len>=16) {
+        const BYTE* const limit = bEnd - 16;
+        U32 v1 = seed + PRIME32_1 + PRIME32_2;
+        U32 v2 = seed + PRIME32_2;
+        U32 v3 = seed + 0;
+        U32 v4 = seed - PRIME32_1;
+
+        do {
+            v1 = XXH32_round(v1, XXH_get32bits(p)); p+=4;
+            v2 = XXH32_round(v2, XXH_get32bits(p)); p+=4;
+            v3 = XXH32_round(v3, XXH_get32bits(p)); p+=4;
+            v4 = XXH32_round(v4, XXH_get32bits(p)); p+=4;
+        } while (p<=limit);
+
+        h32 = XXH_rotl32(v1, 1) + XXH_rotl32(v2, 7) + XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18);
+    } else {
+        h32  = seed + PRIME32_5;
+    }
+
+    h32 += (U32) len;
+
+    while (p+4<=bEnd) {
+        h32 += XXH_get32bits(p) * PRIME32_3;
+        h32  = XXH_rotl32(h32, 17) * PRIME32_4 ;
+        p+=4;
+    }
+
+    while (p<bEnd) {
+        h32 += (*p) * PRIME32_5;
+        h32 = XXH_rotl32(h32, 11) * PRIME32_1 ;
+        p++;
+    }
+
+    h32 ^= h32 >> 15;
+    h32 *= PRIME32_2;
+    h32 ^= h32 >> 13;
+    h32 *= PRIME32_3;
+    h32 ^= h32 >> 16;
+
+    return h32;
+}
+
+
+XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int seed)
+{
+#if 0
+    /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
+    XXH32_state_t state;
+    XXH32_reset(&state, seed);
+    XXH32_update(&state, input, len);
+    return XXH32_digest(&state);
+#else
+    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
+
+    if (XXH_FORCE_ALIGN_CHECK) {
+        if ((((size_t)input) & 3) == 0) {   /* Input is 4-bytes aligned, leverage the speed benefit */
+            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+                return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
+            else
+                return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
+    }   }
+
+    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+        return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
+    else
+        return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
+#endif
+}
+
+
+
+/*======   Hash streaming   ======*/
+
+XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
+{
+    return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
+}
+XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
+{
+    XXH_free(statePtr);
+    return XXH_OK;
+}
+
+XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dstState, const XXH32_state_t* srcState)
+{
+    memcpy(dstState, srcState, sizeof(*dstState));
+}
+
+XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, unsigned int seed)
+{
+    XXH32_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
+    memset(&state, 0, sizeof(state)-4);   /* do not write into reserved, for future removal */
+    state.v1 = seed + PRIME32_1 + PRIME32_2;
+    state.v2 = seed + PRIME32_2;
+    state.v3 = seed + 0;
+    state.v4 = seed - PRIME32_1;
+    memcpy(statePtr, &state, sizeof(state));
+    return XXH_OK;
+}
+
+
+FORCE_INLINE XXH_errorcode XXH32_update_endian (XXH32_state_t* state, const void* input, size_t len, XXH_endianess endian)
+{
+    const BYTE* p = (const BYTE*)input;
+    const BYTE* const bEnd = p + len;
+
+#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
+    if (input==NULL) return XXH_ERROR;
+#endif
+
+    state->total_len_32 += (unsigned)len;
+    state->large_len |= (len>=16) | (state->total_len_32>=16);
+
+    if (state->memsize + len < 16)  {   /* fill in tmp buffer */
+        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, len);
+        state->memsize += (unsigned)len;
+        return XXH_OK;
+    }
+
+    if (state->memsize) {   /* some data left from previous update */
+        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, 16-state->memsize);
+        {   const U32* p32 = state->mem32;
+            state->v1 = XXH32_round(state->v1, XXH_readLE32(p32, endian)); p32++;
+            state->v2 = XXH32_round(state->v2, XXH_readLE32(p32, endian)); p32++;
+            state->v3 = XXH32_round(state->v3, XXH_readLE32(p32, endian)); p32++;
+            state->v4 = XXH32_round(state->v4, XXH_readLE32(p32, endian)); p32++;
+        }
+        p += 16-state->memsize;
+        state->memsize = 0;
+    }
+
+    if (p <= bEnd-16) {
+        const BYTE* const limit = bEnd - 16;
+        U32 v1 = state->v1;
+        U32 v2 = state->v2;
+        U32 v3 = state->v3;
+        U32 v4 = state->v4;
+
+        do {
+            v1 = XXH32_round(v1, XXH_readLE32(p, endian)); p+=4;
+            v2 = XXH32_round(v2, XXH_readLE32(p, endian)); p+=4;
+            v3 = XXH32_round(v3, XXH_readLE32(p, endian)); p+=4;
+            v4 = XXH32_round(v4, XXH_readLE32(p, endian)); p+=4;
+        } while (p<=limit);
+
+        state->v1 = v1;
+        state->v2 = v2;
+        state->v3 = v3;
+        state->v4 = v4;
+    }
+
+    if (p < bEnd) {
+        XXH_memcpy(state->mem32, p, (size_t)(bEnd-p));
+        state->memsize = (unsigned)(bEnd-p);
+    }
+
+    return XXH_OK;
+}
+
+XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* state_in, const void* input, size_t len)
+{
+    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
+
+    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+        return XXH32_update_endian(state_in, input, len, XXH_littleEndian);
+    else
+        return XXH32_update_endian(state_in, input, len, XXH_bigEndian);
+}
+
+
+
+FORCE_INLINE U32 XXH32_digest_endian (const XXH32_state_t* state, XXH_endianess endian)
+{
+    const BYTE * p = (const BYTE*)state->mem32;
+    const BYTE* const bEnd = (const BYTE*)(state->mem32) + state->memsize;
+    U32 h32;
+
+    if (state->large_len) {
+        h32 = XXH_rotl32(state->v1, 1) + XXH_rotl32(state->v2, 7) + XXH_rotl32(state->v3, 12) + XXH_rotl32(state->v4, 18);
+    } else {
+        h32 = state->v3 /* == seed */ + PRIME32_5;
+    }
+
+    h32 += state->total_len_32;
+
+    while (p+4<=bEnd) {
+        h32 += XXH_readLE32(p, endian) * PRIME32_3;
+        h32  = XXH_rotl32(h32, 17) * PRIME32_4;
+        p+=4;
+    }
+
+    while (p<bEnd) {
+        h32 += (*p) * PRIME32_5;
+        h32  = XXH_rotl32(h32, 11) * PRIME32_1;
+        p++;
+    }
+
+    h32 ^= h32 >> 15;
+    h32 *= PRIME32_2;
+    h32 ^= h32 >> 13;
+    h32 *= PRIME32_3;
+    h32 ^= h32 >> 16;
+
+    return h32;
+}
+
+
+XXH_PUBLIC_API unsigned int XXH32_digest (const XXH32_state_t* state_in)
+{
+    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
+
+    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+        return XXH32_digest_endian(state_in, XXH_littleEndian);
+    else
+        return XXH32_digest_endian(state_in, XXH_bigEndian);
+}
+
+
+/*======   Canonical representation   ======*/
+
+/*! Default XXH result types are basic unsigned 32 and 64 bits.
+*   The canonical representation follows human-readable write convention, aka big-endian (large digits first).
+*   These functions allow transformation of hash result into and from its canonical format.
+*   This way, hash values can be written into a file or buffer, and remain comparable across different systems and programs.
+*/
+
+XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash)
+{
+    XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t));
+    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash);
+    memcpy(dst, &hash, sizeof(*dst));
+}
+
+XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
+{
+    return XXH_readBE32(src);
+}
+
+
+#ifndef XXH_NO_LONG_LONG
+
+/* *******************************************************************
+*  64-bits hash functions
+*********************************************************************/
+
+/*======   Memory access   ======*/
+
+#ifndef MEM_MODULE
+# define MEM_MODULE
+# if !defined (__VMS) && (defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) )
+#   include <stdint.h>
+    typedef uint64_t U64;
+# else
+    typedef unsigned long long U64;   /* if your compiler doesn't support unsigned long long, replace by another 64-bit type here. Note that xxhash.h will also need to be updated. */
+# endif
+#endif
+
+
+#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
+
+/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
+static U64 XXH_read64(const void* memPtr) { return *(const U64*) memPtr; }
+
+#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
+
+/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
+/* currently only defined for gcc and icc */
+typedef union { U32 u32; U64 u64; } __attribute__((packed)) unalign64;
+static U64 XXH_read64(const void* ptr) { return ((const unalign64*)ptr)->u64; }
+
+#else
+
+/* portable and safe solution. Generally efficient.
+ * see : http://stackoverflow.com/a/32095106/646947
+ */
+
+static U64 XXH_read64(const void* memPtr)
+{
+    U64 val;
+    memcpy(&val, memPtr, sizeof(val));
+    return val;
+}
+
+#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
+
+#if defined(_MSC_VER)     /* Visual Studio */
+#  define XXH_swap64 _byteswap_uint64
+#elif XXH_GCC_VERSION >= 403
+#  define XXH_swap64 __builtin_bswap64
+#else
+static U64 XXH_swap64 (U64 x)
+{
+    return  ((x << 56) & 0xff00000000000000ULL) |
+            ((x << 40) & 0x00ff000000000000ULL) |
+            ((x << 24) & 0x0000ff0000000000ULL) |
+            ((x << 8)  & 0x000000ff00000000ULL) |
+            ((x >> 8)  & 0x00000000ff000000ULL) |
+            ((x >> 24) & 0x0000000000ff0000ULL) |
+            ((x >> 40) & 0x000000000000ff00ULL) |
+            ((x >> 56) & 0x00000000000000ffULL);
+}
+#endif
+
+FORCE_INLINE U64 XXH_readLE64_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
+{
+    if (align==XXH_unaligned)
+        return endian==XXH_littleEndian ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr));
+    else
+        return endian==XXH_littleEndian ? *(const U64*)ptr : XXH_swap64(*(const U64*)ptr);
+}
+
+FORCE_INLINE U64 XXH_readLE64(const void* ptr, XXH_endianess endian)
+{
+    return XXH_readLE64_align(ptr, endian, XXH_unaligned);
+}
+
+static U64 XXH_readBE64(const void* ptr)
+{
+    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr);
+}
+
+
+/*======   xxh64   ======*/
+
+static const U64 PRIME64_1 = 11400714785074694791ULL;
+static const U64 PRIME64_2 = 14029467366897019727ULL;
+static const U64 PRIME64_3 =  1609587929392839161ULL;
+static const U64 PRIME64_4 =  9650029242287828579ULL;
+static const U64 PRIME64_5 =  2870177450012600261ULL;
+
+static U64 XXH64_round(U64 acc, U64 input)
+{
+    acc += input * PRIME64_2;
+    acc  = XXH_rotl64(acc, 31);
+    acc *= PRIME64_1;
+    return acc;
+}
+
+static U64 XXH64_mergeRound(U64 acc, U64 val)
+{
+    val  = XXH64_round(0, val);
+    acc ^= val;
+    acc  = acc * PRIME64_1 + PRIME64_4;
+    return acc;
+}
+
+FORCE_INLINE U64 XXH64_endian_align(const void* input, size_t len, U64 seed, XXH_endianess endian, XXH_alignment align)
+{
+    const BYTE* p = (const BYTE*)input;
+    const BYTE* bEnd = p + len;
+    U64 h64;
+#define XXH_get64bits(p) XXH_readLE64_align(p, endian, align)
+
+#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
+    if (p==NULL) {
+        len=0;
+        bEnd=p=(const BYTE*)(size_t)32;
+    }
+#endif
+
+    if (len>=32) {
+        const BYTE* const limit = bEnd - 32;
+        U64 v1 = seed + PRIME64_1 + PRIME64_2;
+        U64 v2 = seed + PRIME64_2;
+        U64 v3 = seed + 0;
+        U64 v4 = seed - PRIME64_1;
+
+        do {
+            v1 = XXH64_round(v1, XXH_get64bits(p)); p+=8;
+            v2 = XXH64_round(v2, XXH_get64bits(p)); p+=8;
+            v3 = XXH64_round(v3, XXH_get64bits(p)); p+=8;
+            v4 = XXH64_round(v4, XXH_get64bits(p)); p+=8;
+        } while (p<=limit);
+
+        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
+        h64 = XXH64_mergeRound(h64, v1);
+        h64 = XXH64_mergeRound(h64, v2);
+        h64 = XXH64_mergeRound(h64, v3);
+        h64 = XXH64_mergeRound(h64, v4);
+
+    } else {
+        h64  = seed + PRIME64_5;
+    }
+
+    h64 += (U64) len;
+
+    while (p+8<=bEnd) {
+        U64 const k1 = XXH64_round(0, XXH_get64bits(p));
+        h64 ^= k1;
+        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
+        p+=8;
+    }
+
+    if (p+4<=bEnd) {
+        h64 ^= (U64)(XXH_get32bits(p)) * PRIME64_1;
+        h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+        p+=4;
+    }
+
+    while (p<bEnd) {
+        h64 ^= (*p) * PRIME64_5;
+        h64 = XXH_rotl64(h64, 11) * PRIME64_1;
+        p++;
+    }
+
+    h64 ^= h64 >> 33;
+    h64 *= PRIME64_2;
+    h64 ^= h64 >> 29;
+    h64 *= PRIME64_3;
+    h64 ^= h64 >> 32;
+
+    return h64;
+}
+
+
+XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned long long seed)
+{
+#if 0
+    /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
+    XXH64_state_t state;
+    XXH64_reset(&state, seed);
+    XXH64_update(&state, input, len);
+    return XXH64_digest(&state);
+#else
+    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
+
+    if (XXH_FORCE_ALIGN_CHECK) {
+        if ((((size_t)input) & 7)==0) {  /* Input is aligned, let's leverage the speed advantage */
+            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+                return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
+            else
+                return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
+    }   }
+
+    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+        return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
+    else
+        return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
+#endif
+}
+
+/*======   Hash Streaming   ======*/
+
+XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
+{
+    return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
+}
+XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
+{
+    XXH_free(statePtr);
+    return XXH_OK;
+}
+
+XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dstState, const XXH64_state_t* srcState)
+{
+    memcpy(dstState, srcState, sizeof(*dstState));
+}
+
+XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, unsigned long long seed)
+{
+    XXH64_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
+    memset(&state, 0, sizeof(state)-8);   /* do not write into reserved, for future removal */
+    state.v1 = seed + PRIME64_1 + PRIME64_2;
+    state.v2 = seed + PRIME64_2;
+    state.v3 = seed + 0;
+    state.v4 = seed - PRIME64_1;
+    memcpy(statePtr, &state, sizeof(state));
+    return XXH_OK;
+}
+
+FORCE_INLINE XXH_errorcode XXH64_update_endian (XXH64_state_t* state, const void* input, size_t len, XXH_endianess endian)
+{
+    const BYTE* p = (const BYTE*)input;
+    const BYTE* const bEnd = p + len;
+
+#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
+    if (input==NULL) return XXH_ERROR;
+#endif
+
+    state->total_len += len;
+
+    if (state->memsize + len < 32) {  /* fill in tmp buffer */
+        XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, len);
+        state->memsize += (U32)len;
+        return XXH_OK;
+    }
+
+    if (state->memsize) {   /* tmp buffer is full */
+        XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, 32-state->memsize);
+        state->v1 = XXH64_round(state->v1, XXH_readLE64(state->mem64+0, endian));
+        state->v2 = XXH64_round(state->v2, XXH_readLE64(state->mem64+1, endian));
+        state->v3 = XXH64_round(state->v3, XXH_readLE64(state->mem64+2, endian));
+        state->v4 = XXH64_round(state->v4, XXH_readLE64(state->mem64+3, endian));
+        p += 32-state->memsize;
+        state->memsize = 0;
+    }
+
+    if (p+32 <= bEnd) {
+        const BYTE* const limit = bEnd - 32;
+        U64 v1 = state->v1;
+        U64 v2 = state->v2;
+        U64 v3 = state->v3;
+        U64 v4 = state->v4;
+
+        do {
+            v1 = XXH64_round(v1, XXH_readLE64(p, endian)); p+=8;
+            v2 = XXH64_round(v2, XXH_readLE64(p, endian)); p+=8;
+            v3 = XXH64_round(v3, XXH_readLE64(p, endian)); p+=8;
+            v4 = XXH64_round(v4, XXH_readLE64(p, endian)); p+=8;
+        } while (p<=limit);
+
+        state->v1 = v1;
+        state->v2 = v2;
+        state->v3 = v3;
+        state->v4 = v4;
+    }
+
+    if (p < bEnd) {
+        XXH_memcpy(state->mem64, p, (size_t)(bEnd-p));
+        state->memsize = (unsigned)(bEnd-p);
+    }
+
+    return XXH_OK;
+}
+
+XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* state_in, const void* input, size_t len)
+{
+    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
+
+    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+        return XXH64_update_endian(state_in, input, len, XXH_littleEndian);
+    else
+        return XXH64_update_endian(state_in, input, len, XXH_bigEndian);
+}
+
+FORCE_INLINE U64 XXH64_digest_endian (const XXH64_state_t* state, XXH_endianess endian)
+{
+    const BYTE * p = (const BYTE*)state->mem64;
+    const BYTE* const bEnd = (const BYTE*)state->mem64 + state->memsize;
+    U64 h64;
+
+    if (state->total_len >= 32) {
+        U64 const v1 = state->v1;
+        U64 const v2 = state->v2;
+        U64 const v3 = state->v3;
+        U64 const v4 = state->v4;
+
+        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
+        h64 = XXH64_mergeRound(h64, v1);
+        h64 = XXH64_mergeRound(h64, v2);
+        h64 = XXH64_mergeRound(h64, v3);
+        h64 = XXH64_mergeRound(h64, v4);
+    } else {
+        h64  = state->v3 + PRIME64_5;
+    }
+
+    h64 += (U64) state->total_len;
+
+    while (p+8<=bEnd) {
+        U64 const k1 = XXH64_round(0, XXH_readLE64(p, endian));
+        h64 ^= k1;
+        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
+        p+=8;
+    }
+
+    if (p+4<=bEnd) {
+        h64 ^= (U64)(XXH_readLE32(p, endian)) * PRIME64_1;
+        h64  = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
+        p+=4;
+    }
+
+    while (p<bEnd) {
+        h64 ^= (*p) * PRIME64_5;
+        h64  = XXH_rotl64(h64, 11) * PRIME64_1;
+        p++;
+    }
+
+    h64 ^= h64 >> 33;
+    h64 *= PRIME64_2;
+    h64 ^= h64 >> 29;
+    h64 *= PRIME64_3;
+    h64 ^= h64 >> 32;
+
+    return h64;
+}
+
+XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* state_in)
+{
+    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
+
+    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
+        return XXH64_digest_endian(state_in, XXH_littleEndian);
+    else
+        return XXH64_digest_endian(state_in, XXH_bigEndian);
+}
+
+
+/*====== Canonical representation   ======*/
+
+XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash)
+{
+    XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t));
+    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash);
+    memcpy(dst, &hash, sizeof(*dst));
+}
+
+XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
+{
+    return XXH_readBE64(src);
+}
+
+#endif  /* XXH_NO_LONG_LONG */

src/libraries/xxHash/xxhash.h

@@ -0,0 +1,293 @@
+/*
+   xxHash - Extremely Fast Hash algorithm
+   Header File
+   Copyright (C) 2012-2016, Yann Collet.
+
+   BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+       * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+       * Redistributions in binary form must reproduce the above
+   copyright notice, this list of conditions and the following disclaimer
+   in the documentation and/or other materials provided with the
+   distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+   You can contact the author at :
+   - xxHash source repository : https://github.com/Cyan4973/xxHash
+*/
+
+/* Notice extracted from xxHash homepage :
+
+xxHash is an extremely fast Hash algorithm, running at RAM speed limits.
+It also successfully passes all tests from the SMHasher suite.
+
+Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 Duo @3GHz)
+
+Name            Speed       Q.Score   Author
+xxHash          5.4 GB/s     10
+CrapWow         3.2 GB/s      2       Andrew
+MumurHash 3a    2.7 GB/s     10       Austin Appleby
+SpookyHash      2.0 GB/s     10       Bob Jenkins
+SBox            1.4 GB/s      9       Bret Mulvey
+Lookup3         1.2 GB/s      9       Bob Jenkins
+SuperFastHash   1.2 GB/s      1       Paul Hsieh
+CityHash64      1.05 GB/s    10       Pike & Alakuijala
+FNV             0.55 GB/s     5       Fowler, Noll, Vo
+CRC32           0.43 GB/s     9
+MD5-32          0.33 GB/s    10       Ronald L. Rivest
+SHA1-32         0.28 GB/s    10
+
+Q.Score is a measure of quality of the hash function.
+It depends on successfully passing SMHasher test set.
+10 is a perfect score.
+
+A 64-bits version, named XXH64, is available since r35.
+It offers much better speed, but for 64-bits applications only.
+Name     Speed on 64 bits    Speed on 32 bits
+XXH64       13.8 GB/s            1.9 GB/s
+XXH32        6.8 GB/s            6.0 GB/s
+*/
+
+#ifndef XXHASH_H_5627135585666179
+#define XXHASH_H_5627135585666179 1
+
+#if defined (__cplusplus)
+extern "C" {
+#endif
+
+
+/* ****************************
+*  Definitions
+******************************/
+#include <stddef.h>   /* size_t */
+typedef enum { XXH_OK=0, XXH_ERROR } XXH_errorcode;
+
+
+/* ****************************
+*  API modifier
+******************************/
+/** XXH_PRIVATE_API
+*   This is useful to include xxhash functions in `static` mode
+*   in order to inline them, and remove their symbol from the public list.
+*   Methodology :
+*     #define XXH_PRIVATE_API
+*     #include "xxhash.h"
+*   `xxhash.c` is automatically included.
+*   It's not useful to compile and link it as a separate module.
+*/
+#ifdef XXH_PRIVATE_API
+#  ifndef XXH_STATIC_LINKING_ONLY
+#    define XXH_STATIC_LINKING_ONLY
+#  endif
+#  if defined(__GNUC__)
+#    define XXH_PUBLIC_API static __inline __attribute__((unused))
+#  elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
+#    define XXH_PUBLIC_API static inline
+#  elif defined(_MSC_VER)
+#    define XXH_PUBLIC_API static __inline
+#  else
+#    define XXH_PUBLIC_API static   /* this version may generate warnings for unused static functions; disable the relevant warning */
+#  endif
+#else
+#  define XXH_PUBLIC_API   /* do nothing */
+#endif /* XXH_PRIVATE_API */
+
+/*!XXH_NAMESPACE, aka Namespace Emulation :
+
+If you want to include _and expose_ xxHash functions from within your own library,
+but also want to avoid symbol collisions with other libraries which may also include xxHash,
+
+you can use XXH_NAMESPACE, to automatically prefix any public symbol from xxhash library
+with the value of XXH_NAMESPACE (therefore, avoid NULL and numeric values).
+
+Note that no change is required within the calling program as long as it includes `xxhash.h` :
+regular symbol name will be automatically translated by this header.
+*/
+#ifdef XXH_NAMESPACE
+#  define XXH_CAT(A,B) A##B
+#  define XXH_NAME2(A,B) XXH_CAT(A,B)
+#  define XXH_versionNumber XXH_NAME2(XXH_NAMESPACE, XXH_versionNumber)
+#  define XXH32 XXH_NAME2(XXH_NAMESPACE, XXH32)
+#  define XXH32_createState XXH_NAME2(XXH_NAMESPACE, XXH32_createState)
+#  define XXH32_freeState XXH_NAME2(XXH_NAMESPACE, XXH32_freeState)
+#  define XXH32_reset XXH_NAME2(XXH_NAMESPACE, XXH32_reset)
+#  define XXH32_update XXH_NAME2(XXH_NAMESPACE, XXH32_update)
+#  define XXH32_digest XXH_NAME2(XXH_NAMESPACE, XXH32_digest)
+#  define XXH32_copyState XXH_NAME2(XXH_NAMESPACE, XXH32_copyState)
+#  define XXH32_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH32_canonicalFromHash)
+#  define XXH32_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH32_hashFromCanonical)
+#  define XXH64 XXH_NAME2(XXH_NAMESPACE, XXH64)
+#  define XXH64_createState XXH_NAME2(XXH_NAMESPACE, XXH64_createState)
+#  define XXH64_freeState XXH_NAME2(XXH_NAMESPACE, XXH64_freeState)
+#  define XXH64_reset XXH_NAME2(XXH_NAMESPACE, XXH64_reset)
+#  define XXH64_update XXH_NAME2(XXH_NAMESPACE, XXH64_update)
+#  define XXH64_digest XXH_NAME2(XXH_NAMESPACE, XXH64_digest)
+#  define XXH64_copyState XXH_NAME2(XXH_NAMESPACE, XXH64_copyState)
+#  define XXH64_canonicalFromHash XXH_NAME2(XXH_NAMESPACE, XXH64_canonicalFromHash)
+#  define XXH64_hashFromCanonical XXH_NAME2(XXH_NAMESPACE, XXH64_hashFromCanonical)
+#endif
+
+
+/* *************************************
+*  Version
+***************************************/
+#define XXH_VERSION_MAJOR    0
+#define XXH_VERSION_MINOR    6
+#define XXH_VERSION_RELEASE  2
+#define XXH_VERSION_NUMBER  (XXH_VERSION_MAJOR *100*100 + XXH_VERSION_MINOR *100 + XXH_VERSION_RELEASE)
+XXH_PUBLIC_API unsigned XXH_versionNumber (void);
+
+
+/*-**********************************************************************
+*  32-bits hash
+************************************************************************/
+typedef unsigned int XXH32_hash_t;
+
+/*! XXH32() :
+    Calculate the 32-bits hash of sequence "length" bytes stored at memory address "input".
+    The memory between input & input+length must be valid (allocated and read-accessible).
+    "seed" can be used to alter the result predictably.
+    Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s */
+XXH_PUBLIC_API XXH32_hash_t XXH32 (const void* input, size_t length, unsigned int seed);
+
+/*======   Streaming   ======*/
+typedef struct XXH32_state_s XXH32_state_t;   /* incomplete type */
+XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void);
+XXH_PUBLIC_API XXH_errorcode  XXH32_freeState(XXH32_state_t* statePtr);
+XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* dst_state, const XXH32_state_t* src_state);
+
+XXH_PUBLIC_API XXH_errorcode XXH32_reset  (XXH32_state_t* statePtr, unsigned int seed);
+XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* statePtr, const void* input, size_t length);
+XXH_PUBLIC_API XXH32_hash_t  XXH32_digest (const XXH32_state_t* statePtr);
+
+/*
+These functions generate the xxHash of an input provided in multiple segments.
+Note that, for small input, they are slower than single-call functions, due to state management.
+For small input, prefer `XXH32()` and `XXH64()` .
+
+XXH state must first be allocated, using XXH*_createState() .
+
+Start a new hash by initializing state with a seed, using XXH*_reset().
+
+Then, feed the hash state by calling XXH*_update() as many times as necessary.
+Obviously, input must be allocated and read accessible.
+The function returns an error code, with 0 meaning OK, and any other value meaning there is an error.
+
+Finally, a hash value can be produced anytime, by using XXH*_digest().
+This function returns the nn-bits hash as an int or long long.
+
+It's still possible to continue inserting input into the hash state after a digest,
+and generate some new hashes later on, by calling again XXH*_digest().
+
+When done, free XXH state space if it was allocated dynamically.
+*/
+
+/*======   Canonical representation   ======*/
+
+typedef struct { unsigned char digest[4]; } XXH32_canonical_t;
+XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash);
+XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src);
+
+/* Default result type for XXH functions are primitive unsigned 32 and 64 bits.
+*  The canonical representation uses human-readable write convention, aka big-endian (large digits first).
+*  These functions allow transformation of hash result into and from its canonical format.
+*  This way, hash values can be written into a file / memory, and remain comparable on different systems and programs.
+*/
+
+
+#ifndef XXH_NO_LONG_LONG
+/*-**********************************************************************
+*  64-bits hash
+************************************************************************/
+typedef unsigned long long XXH64_hash_t;
+
+/*! XXH64() :
+    Calculate the 64-bits hash of sequence of length "len" stored at memory address "input".
+    "seed" can be used to alter the result predictably.
+    This function runs faster on 64-bits systems, but slower on 32-bits systems (see benchmark).
+*/
+XXH_PUBLIC_API XXH64_hash_t XXH64 (const void* input, size_t length, unsigned long long seed);
+
+/*======   Streaming   ======*/
+typedef struct XXH64_state_s XXH64_state_t;   /* incomplete type */
+XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void);
+XXH_PUBLIC_API XXH_errorcode  XXH64_freeState(XXH64_state_t* statePtr);
+XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* dst_state, const XXH64_state_t* src_state);
+
+XXH_PUBLIC_API XXH_errorcode XXH64_reset  (XXH64_state_t* statePtr, unsigned long long seed);
+XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* statePtr, const void* input, size_t length);
+XXH_PUBLIC_API XXH64_hash_t  XXH64_digest (const XXH64_state_t* statePtr);
+
+/*======   Canonical representation   ======*/
+typedef struct { unsigned char digest[8]; } XXH64_canonical_t;
+XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash);
+XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src);
+#endif  /* XXH_NO_LONG_LONG */
+
+
+#ifdef XXH_STATIC_LINKING_ONLY
+
+/* ================================================================================================
+   This section contains definitions which are not guaranteed to remain stable.
+   They may change in future versions, becoming incompatible with a different version of the library.
+   They shall only be used with static linking.
+   Never use these definitions in association with dynamic linking !
+=================================================================================================== */
+
+/* These definitions are only meant to make possible
+   static allocation of XXH state, on stack or in a struct for example.
+   Never use members directly. */
+
+struct XXH32_state_s {
+   unsigned total_len_32;
+   unsigned large_len;
+   unsigned v1;
+   unsigned v2;
+   unsigned v3;
+   unsigned v4;
+   unsigned mem32[4];   /* buffer defined as U32 for alignment */
+   unsigned memsize;
+   unsigned reserved;   /* never read nor write, will be removed in a future version */
+};   /* typedef'd to XXH32_state_t */
+
+#ifndef XXH_NO_LONG_LONG   /* remove 64-bits support */
+struct XXH64_state_s {
+   unsigned long long total_len;
+   unsigned long long v1;
+   unsigned long long v2;
+   unsigned long long v3;
+   unsigned long long v4;
+   unsigned long long mem64[4];   /* buffer defined as U64 for alignment */
+   unsigned memsize;
+   unsigned reserved[2];          /* never read nor write, will be removed in a future version */
+};   /* typedef'd to XXH64_state_t */
+#endif
+
+#ifdef XXH_PRIVATE_API
+#  include "xxhash.c"   /* include xxhash function bodies as `static`, for inlining */
+#endif
+
+#endif /* XXH_STATIC_LINKING_ONLY */
+
+
+#if defined (__cplusplus)
+}
+#endif
+
+#endif /* XXHASH_H_5627135585666179 */

src/modules/event/sdl/Event.cpp

@@ -112,6 +112,8 @@ Event::~Event()
 
 void Event::pump()
 {
+	exceptionIfInRenderPass();
+
 	SDL_Event e;
 
 	while (SDL_PollEvent(&e))
@@ -127,6 +129,8 @@ void Event::pump()
 
 Message *Event::wait()
 {
+	exceptionIfInRenderPass();
+
 	SDL_Event e;
 
 	if (SDL_WaitEvent(&e) != 1)
@@ -137,6 +141,8 @@ Message *Event::wait()
 
 void Event::clear()
 {
+	exceptionIfInRenderPass();
+
 	SDL_Event e;
 
 	while (SDL_PollEvent(&e))
@@ -147,6 +153,17 @@ void Event::clear()
 	love::event::Event::clear();
 }
 
+void Event::exceptionIfInRenderPass()
+{
+	// Some core OS graphics functionality (e.g. swap buffers on some platforms)
+	// happens inside SDL_PumpEvents - which is called by SDL_PollEvent and
+	// friends. It's probably a bad idea to call those functions while we're in
+	// a render pass.
+	auto gfx = Module::getInstance<graphics::Graphics>(Module::M_GRAPHICS);
+	if (gfx != nullptr && gfx->isPassActive())
+		throw love::Exception("Cannot call this function while a render pass is active in love.graphics.");
+}
+
 Message *Event::convert(const SDL_Event &e) const
 {
 	Message *msg = nullptr;

src/modules/event/sdl/Event.h

@@ -68,6 +68,8 @@ public:
 
 private:
 
+	void exceptionIfInRenderPass();
+
 	Message *convert(const SDL_Event &e) const;
 	Message *convertJoystickEvent(const SDL_Event &e) const;
 	Message *convertWindowEvent(const SDL_Event &e) const;

src/modules/event/wrap_Event.cpp

@@ -53,15 +53,16 @@ int w_poll(lua_State *L)
 	return 1;
 }
 
-int w_pump(lua_State *)
+int w_pump(lua_State *L)
 {
-	instance()->pump();
+	luax_catchexcept(L, [&]() { instance()->pump(); });
 	return 0;
 }
 
 int w_wait(lua_State *L)
 {
-	Message *m = instance()->wait();
+	Message *m = nullptr;
+	luax_catchexcept(L, [&]() { m = instance()->wait(); });
 	if (m)
 	{
 		int args = m->toLua(L);
@@ -85,9 +86,9 @@ int w_push(lua_State *L)
 	return 1;
 }
 
-int w_clear(lua_State *)
+int w_clear(lua_State *L)
 {
-	instance()->clear();
+	luax_catchexcept(L, [&]() { instance()->clear(); });
 	return 0;
 }
 

src/modules/graphics/Graphics.h

@@ -34,6 +34,8 @@ namespace love
 namespace graphics
 {
 
+const int MAX_COLOR_RENDER_TARGETS = 16;
+
 /**
  * Globally sets whether gamma correction is enabled. Ideally this should be set
  * prior to using any Graphics module function.
@@ -59,6 +61,14 @@ void gammaCorrectColor(Colorf &c);
  **/
 void unGammaCorrectColor(Colorf &c);
 
+class RenderOutsidePassException : public love::Exception
+{
+public:
+	RenderOutsidePassException()
+		: Exception("Cannot draw outside of a render pass!")
+	{}
+};
+
 class Graphics : public Module
 {
 public:
@@ -178,7 +188,7 @@ public:
 	struct Stats
 	{
 		int drawCalls;
-		int canvasSwitches;
+		int renderPasses;
 		int shaderSwitches;
 		int canvases;
 		int images;
@@ -257,6 +267,8 @@ public:
 	 **/
 	virtual bool isActive() const = 0;
 
+	virtual bool isPassActive() const = 0;
+
 	static bool getConstant(const char *in, DrawMode &out);
 	static bool getConstant(DrawMode in, const char *&out);
 

src/modules/graphics/opengl/Canvas.cpp

@@ -36,11 +36,10 @@ namespace opengl
 static GLenum createFBO(GLuint &framebuffer, GLuint texture)
 {
 	// get currently bound fbo to reset to it later
-	GLint current_fbo;
-	glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &current_fbo);
+	GLuint current_fbo = gl.getFramebuffer(OpenGL::FRAMEBUFFER_ALL);
 
 	glGenFramebuffers(1, &framebuffer);
-	gl.bindFramebuffer(GL_FRAMEBUFFER, framebuffer);
+	gl.bindFramebuffer(OpenGL::FRAMEBUFFER_ALL, framebuffer);
 
 	if (texture != 0)
 	{
@@ -53,14 +52,19 @@ static GLenum createFBO(GLuint &framebuffer, GLuint texture)
 
 	GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 
-	// unbind framebuffer
-	gl.bindFramebuffer(GL_FRAMEBUFFER, (GLuint) current_fbo);
-
+	gl.bindFramebuffer(OpenGL::FRAMEBUFFER_ALL, current_fbo);
 	return status;
 }
 
-static GLenum createMSAABuffer(int width, int height, int &samples, GLenum iformat, GLuint &buffer)
+static bool createMSAABuffer(int width, int height, int &samples, GLenum iformat, GLuint &buffer)
 {
+	GLuint current_fbo = gl.getFramebuffer(OpenGL::FRAMEBUFFER_ALL);
+
+	// Temporary FBO used to clear the renderbuffer.
+	GLuint fbo = 0;
+	glGenFramebuffers(1, &fbo);
+	gl.bindFramebuffer(OpenGL::FRAMEBUFFER_ALL, fbo);
+
 	glGenRenderbuffers(1, &buffer);
 	glBindRenderbuffer(GL_RENDERBUFFER, buffer);
 
@@ -73,7 +77,7 @@ static GLenum createMSAABuffer(int width, int height, int &samples, GLenum iform
 
 	GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 
-	if (status == GL_FRAMEBUFFER_COMPLETE)
+	if (status == GL_FRAMEBUFFER_COMPLETE && samples > 1)
 	{
 		// Initialize the buffer to transparent black.
 		glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
@@ -83,22 +87,21 @@ static GLenum createMSAABuffer(int width, int height, int &samples, GLenum iform
 	{
 		glDeleteRenderbuffers(1, &buffer);
 		buffer = 0;
+		samples = 0;
 	}
 
-	return status;
+	gl.bindFramebuffer(OpenGL::FRAMEBUFFER_ALL, current_fbo);
+	gl.deleteFramebuffer(fbo);
+
+	return status == GL_FRAMEBUFFER_COMPLETE && samples > 1;
 }
 
-Canvas *Canvas::current = nullptr;
-OpenGL::Viewport Canvas::systemViewport = OpenGL::Viewport();
-bool Canvas::screenHasSRGB = false;
 int Canvas::canvasCount = 0;
 
 Canvas::Canvas(int width, int height, Format format, int msaa)
 	: fbo(0)
-    , resolve_fbo(0)
 	, texture(0)
     , msaa_buffer(0)
-	, depth_stencil(0)
 	, format(format)
     , requested_samples(msaa)
 	, actual_samples(0)
@@ -143,65 +146,15 @@ Canvas::Canvas(int width, int height, Format format, int msaa)
 Canvas::~Canvas()
 {
 	--canvasCount;
-
-	// reset framebuffer if still using this one
-	if (current == this)
-		stopGrab();
-
 	unloadVolatile();
 }
 
-bool Canvas::createMSAAFBO(GLenum internalformat)
-{
-	actual_samples = requested_samples;
-
-	if (actual_samples <= 1)
-	{
-		actual_samples = 0;
-		return false;
-	}
-
-	// Create our FBO without a texture.
-	status = createFBO(fbo, 0);
-
-	GLuint previous = gl.getDefaultFBO();
-	if (current != this)
-	{
-		if (current != nullptr)
-			previous = current->fbo;
-
-		gl.bindFramebuffer(GL_FRAMEBUFFER, fbo);
-	}
-
-	// Create and attach the MSAA buffer for our FBO.
-	status = createMSAABuffer(width, height, actual_samples, internalformat, msaa_buffer);
-
-	// Create the FBO used for the MSAA resolve, and attach the texture.
-	if (status == GL_FRAMEBUFFER_COMPLETE)
-		status = createFBO(resolve_fbo, texture);
-
-	if (status != GL_FRAMEBUFFER_COMPLETE)
-	{
-		// Clean up.
-		glDeleteFramebuffers(1, &fbo);
-		glDeleteFramebuffers(1, &resolve_fbo);
-		glDeleteRenderbuffers(1, &msaa_buffer);
-		fbo = msaa_buffer = resolve_fbo = 0;
-		actual_samples = 0;
-	}
-
-	if (current != this)
-		gl.bindFramebuffer(GL_FRAMEBUFFER, previous);
-
-	return status == GL_FRAMEBUFFER_COMPLETE;
-}
-
 bool Canvas::loadVolatile()
 {
 	OpenGL::TempDebugGroup debuggroup("Canvas load");
 
-	fbo = depth_stencil = texture = 0;
-	resolve_fbo = msaa_buffer = 0;
+	fbo = texture = 0;
+	msaa_buffer = 0;
 	status = GL_FRAMEBUFFER_COMPLETE;
 
 	// glTexImage2D is guaranteed to error in this case.
@@ -239,8 +192,8 @@ bool Canvas::loadVolatile()
 	while (glGetError() != GL_NO_ERROR)
 		/* Clear the error buffer. */;
 
-	glTexImage2D(GL_TEXTURE_2D, 0, iformat, width, height, 0,
-	             externalformat, textype, nullptr);
+	glTexImage2D(GL_TEXTURE_2D, 0, iformat, width, height, 0, externalformat,
+	             textype, nullptr);
 
 	if (glGetError() != GL_NO_ERROR)
 	{
@@ -250,24 +203,27 @@ bool Canvas::loadVolatile()
 		return false;
 	}
 
-	// Try to create a MSAA FBO if requested. On failure (or no requested MSAA),
-	// fall back to a regular FBO.
-	if (!createMSAAFBO(internalformat))
-		status = createFBO(fbo, texture);
+	// Create a canvas-local FBO used for glReadPixels as well as MSAA blitting.
+	status = createFBO(fbo, texture);
 
 	if (status != GL_FRAMEBUFFER_COMPLETE)
-    {
-        if (fbo != 0)
-        {
-			glDeleteFramebuffers(1, &fbo);
-            fbo = 0;
-        }
+	{
+		if (fbo != 0)
+		{
+			gl.deleteFramebuffer(fbo);
+			fbo = 0;
+		}
 		return false;
-    }
+	}
+
+	actual_samples = requested_samples == 1 ? 0 : requested_samples;
+
+	if (actual_samples > 0 && !createMSAABuffer(width, height, actual_samples, internalformat, msaa_buffer))
+		actual_samples = 0;
 
 	size_t prevmemsize = texture_memory;
 
-	texture_memory = (getFormatBitsPerPixel(format) * width * height) / 8;
+	texture_memory = ((getFormatBitsPerPixel(format) * width) / 8) * height;
 	if (msaa_buffer != 0)
 		texture_memory += (texture_memory * actual_samples);
 
@@ -278,33 +234,35 @@ bool Canvas::loadVolatile()
 
 void Canvas::unloadVolatile()
 {
-	glDeleteFramebuffers(1, &fbo);
-	glDeleteFramebuffers(1, &resolve_fbo);
+	if (fbo != 0)
+		gl.deleteFramebuffer(fbo);
 
-	glDeleteRenderbuffers(1, &depth_stencil);
-	glDeleteRenderbuffers(1, &msaa_buffer);
+	if (msaa_buffer != 0)
+		glDeleteRenderbuffers(1, &msaa_buffer);
 
-	gl.deleteTexture(texture);
+	if (texture != 0)
+		gl.deleteTexture(texture);
 
 	fbo = 0;
-	resolve_fbo = 0;
-	depth_stencil = 0;
 	msaa_buffer = 0;
 	texture = 0;
 
-	attachedCanvases.clear();
-
 	gl.updateTextureMemorySize(texture_memory, 0);
 	texture_memory = 0;
 }
 
 void Canvas::drawv(const Matrix4 &t, const Vertex *v)
 {
-	// FIXME: This doesn't handle cases where the Canvas is used as a texture
-	// in a SpriteBatch, Mesh, or ParticleSystem, or when the Canvas is used in
-	// a shader as a non-default texture.
-	if (Canvas::current == this)
-		throw love::Exception("Cannot draw a Canvas to itself.");
+	auto gfx = Module::getInstance<Graphics>(Module::M_GRAPHICS);
+	if (gfx != nullptr)
+	{
+		const PassInfo &info = gfx->getActivePass();
+		for (const auto &attachment : info.colorAttachments)
+		{
+			if (attachment.canvas == this)
+				throw love::Exception("Cannot render a Canvas to itself!");
+		}
+	}
 
 	OpenGL::TempDebugGroup debuggroup("Canvas draw");
 
@@ -377,320 +335,6 @@ const void *Canvas::getHandle() const
 	return &texture;
 }
 
-void Canvas::setupGrab()
-{
-	// already grabbing
-	if (current == this)
-		return;
-
-	// cleanup after previous Canvas
-	if (current != nullptr)
-	{
-		systemViewport = current->systemViewport;
-		current->stopGrab(true);
-	}
-	else
-		systemViewport = gl.getViewport();
-
-	// indicate we are using this Canvas.
-	current = this;
-
-	// bind the framebuffer object.
-	gl.bindFramebuffer(GL_FRAMEBUFFER, fbo);
-	gl.setViewport({0, 0, width, height});
-
-	// Set up the projection matrix
-	gl.matrices.projection.push_back(Matrix4::ortho(0.0, (float) width, 0.0, (float) height));
-}
-
-void Canvas::startGrab(const std::vector<Canvas *> &canvases)
-{
-	// Whether the new canvas list is different from the old one.
-	// A more thorough check is done below.
-	bool canvaseschanged = canvases.size() != attachedCanvases.size();
-	bool hasSRGBcanvas = getSizedFormat(format) == FORMAT_SRGB;
-
-	if (canvases.size() > 0)
-	{
-		if ((int) canvases.size() + 1 > gl.getMaxRenderTargets())
-			throw love::Exception("This system can't simultaneously render to %d canvases.", canvases.size()+1);
-
-		if (actual_samples != 0)
-			throw love::Exception("Multi-canvas rendering is not supported with MSAA.");
-	}
-
-	bool multiformatsupported = isMultiFormatMultiCanvasSupported();
-
-	for (size_t i = 0; i < canvases.size(); i++)
-	{
-		if (canvases[i]->getWidth() != width || canvases[i]->getHeight() != height)
-			throw love::Exception("All canvases must have the same dimensions.");
-
-		Format otherformat = canvases[i]->getTextureFormat();
-
-		if (otherformat != format && !multiformatsupported)
-			throw love::Exception("This system doesn't support multi-canvas rendering with different canvas formats.");
-
-		if (canvases[i]->getMSAA() != 0)
-			throw love::Exception("Multi-canvas rendering is not supported with MSAA.");
-
-		if (!canvaseschanged && canvases[i] != attachedCanvases[i])
-			canvaseschanged = true;
-
-		if (getSizedFormat(otherformat) == FORMAT_SRGB)
-			hasSRGBcanvas = true;
-	}
-
-	OpenGL::TempDebugGroup debuggroup("Canvas set");
-
-	setupGrab();
-
-	// Make sure the correct sRGB setting is used when drawing to the canvases.
-	if (GLAD_VERSION_1_0 || GLAD_EXT_sRGB_write_control)
-	{
-		if (hasSRGBcanvas && !gl.hasFramebufferSRGB())
-			gl.setFramebufferSRGB(true);
-		else if (!hasSRGBcanvas && gl.hasFramebufferSRGB())
-			gl.setFramebufferSRGB(false);
-	}
-
-	// Don't attach anything if there's nothing to change.
-	if (!canvaseschanged)
-		return;
-
-	// Attach the canvas textures to the active FBO and set up MRTs.
-	std::vector<GLenum> drawbuffers;
-	drawbuffers.reserve(canvases.size() + 1);
-
-	drawbuffers.push_back(GL_COLOR_ATTACHMENT0);
-
-	// Attach the canvas textures to the currently bound framebuffer.
-	for (int i = 0; i < (int) canvases.size(); i++)
-	{
-		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1 + i,
-		                       GL_TEXTURE_2D, *(GLuint *) canvases[i]->getHandle(), 0);
-
-		drawbuffers.push_back(GL_COLOR_ATTACHMENT1 + i);
-	}
-
-	// set up multiple render targets
-	glDrawBuffers((int) drawbuffers.size(), &drawbuffers[0]);
-
-	// We want to avoid reference cycles, so we don't retain the attached
-	// Canvases here. The code in Graphics::setCanvas retains them.
-
-	attachedCanvases = canvases;
-}
-
-void Canvas::startGrab()
-{
-	OpenGL::TempDebugGroup debuggroup("Canvas set");
-
-	setupGrab();
-
-	// Make sure the correct sRGB setting is used when drawing to the canvas.
-	if (GLAD_VERSION_1_0 || GLAD_EXT_sRGB_write_control)
-	{
-		bool isSRGB = getSizedFormat(format) == FORMAT_SRGB;
-		if (isSRGB && !gl.hasFramebufferSRGB())
-			gl.setFramebufferSRGB(true);
-		else if (!isSRGB && gl.hasFramebufferSRGB())
-			gl.setFramebufferSRGB(false);
-	}
-
-	if (attachedCanvases.size() > 0)
-	{
-		// Make sure the FBO is only using a single draw buffer.
-		// GLES3 only has glDrawBuffers, so we avoid using glDrawBuffer.
-		const GLenum buffers[] = {GL_COLOR_ATTACHMENT0};
-		glDrawBuffers(1, buffers);
-
-		attachedCanvases.clear();
-	}
-}
-
-void Canvas::stopGrab(bool switchingToOtherCanvas)
-{
-	// i am not grabbing. leave me alone
-	if (current != this)
-		return;
-
-	OpenGL::TempDebugGroup debuggroup("Canvas un-set");
-
-	// Make sure the canvas texture is up to date if we're using MSAA.
-	resolveMSAA(false);
-
-	if (gl.matrices.projection.size() > 1)
-		gl.matrices.projection.pop_back();
-
-	if (!switchingToOtherCanvas)
-	{
-		// bind system framebuffer.
-		gl.bindFramebuffer(GL_FRAMEBUFFER, gl.getDefaultFBO());
-		current = nullptr;
-		gl.setViewport(systemViewport);
-
-		if (GLAD_VERSION_1_0 || GLAD_EXT_sRGB_write_control)
-		{
-			if (screenHasSRGB && !gl.hasFramebufferSRGB())
-				gl.setFramebufferSRGB(true);
-			else if (!screenHasSRGB && gl.hasFramebufferSRGB())
-				gl.setFramebufferSRGB(false);
-		}
-	}
-}
-
-bool Canvas::checkCreateStencil()
-{
-	// Do nothing if we've already created the stencil buffer.
-	if (depth_stencil != 0)
-		return true;
-
-	OpenGL::TempDebugGroup debuggroup("Canvas create stencil");
-
-	if (current != this)
-		gl.bindFramebuffer(GL_FRAMEBUFFER, fbo);
-
-	GLenum format = GL_STENCIL_INDEX8;
-	std::vector<GLenum> attachments = {GL_STENCIL_ATTACHMENT};
-
-	// Prefer a combined depth/stencil buffer.
-	if (GLAD_ES_VERSION_3_0 || GLAD_VERSION_3_0 || GLAD_ARB_framebuffer_object)
-	{
-		format = GL_DEPTH24_STENCIL8;
-		attachments = {GL_DEPTH_STENCIL_ATTACHMENT};
-	}
-	else if (GLAD_EXT_packed_depth_stencil || GLAD_OES_packed_depth_stencil)
-	{
-		format = GL_DEPTH24_STENCIL8;
-		attachments = {GL_DEPTH_ATTACHMENT, GL_STENCIL_ATTACHMENT};
-	}
-
-	glGenRenderbuffers(1, &depth_stencil);
-	glBindRenderbuffer(GL_RENDERBUFFER, depth_stencil);
-
-	if (requested_samples > 1)
-		glRenderbufferStorageMultisample(GL_RENDERBUFFER, requested_samples, format, width, height);
-	else
-		glRenderbufferStorage(GL_RENDERBUFFER, format, width, height);
-
-	// Attach the buffer to the framebuffer object.
-	for (GLenum attachment : attachments)
-		glFramebufferRenderbuffer(GL_FRAMEBUFFER, attachment, GL_RENDERBUFFER, depth_stencil);
-
-	glBindRenderbuffer(GL_RENDERBUFFER, 0);
-
-	bool success = glCheckFramebufferStatus(GL_FRAMEBUFFER) == GL_FRAMEBUFFER_COMPLETE;
-
-	// We don't want the stencil buffer filled with garbage.
-	if (success)
-		glClear(GL_STENCIL_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-	else
-	{
-		glDeleteRenderbuffers(1, &depth_stencil);
-		depth_stencil = 0;
-	}
-
-	if (current && current != this)
-		gl.bindFramebuffer(GL_FRAMEBUFFER, current->fbo);
-	else if (!current)
-		gl.bindFramebuffer(GL_FRAMEBUFFER, gl.getDefaultFBO());
-
-	return success;
-}
-
-love::image::ImageData *Canvas::newImageData(love::image::Image *image, int x, int y, int w, int h)
-{
-	if (x < 0 || y < 0 || w <= 0 || h <= 0 || (x + w) > width || (y + h) > height)
-		throw love::Exception("Invalid ImageData rectangle dimensions.");
-
-	GLenum datatype = GL_UNSIGNED_BYTE;
-	image::ImageData::Format imageformat = image::ImageData::FORMAT_RGBA8;
-
-	switch (getSizedFormat(format))
-	{
-	case FORMAT_RGB10A2: // FIXME: Conversions aren't supported in GLES
-		datatype = GL_UNSIGNED_SHORT;
-		imageformat = image::ImageData::FORMAT_RGBA16;
-		break;
-	case FORMAT_R16F:
-	case FORMAT_RG16F:
-	case FORMAT_RGBA16F:
-	case FORMAT_RG11B10F: // FIXME: Conversions aren't supported in GLES
-		datatype = GL_HALF_FLOAT;
-		imageformat = image::ImageData::FORMAT_RGBA16F;
-		break;
-	case FORMAT_R32F:
-	case FORMAT_RG32F:
-	case FORMAT_RGBA32F:
-		datatype = GL_FLOAT;
-		imageformat = image::ImageData::FORMAT_RGBA32F;
-		break;
-	default:
-		break;
-	}
-
-	size_t size = w * h * image::ImageData::getPixelSize(imageformat);
-	uint8 *pixels = nullptr;
-	try
-	{
-		pixels = new uint8[size];
-	}
-	catch (std::bad_alloc &)
-	{
-		throw love::Exception("Out of memory.");
-	}
-
-	// Make sure the canvas texture is up to date if we're using MSAA.
-	if (current == this)
-		resolveMSAA(false);
-
-	// Our texture is attached to 'resolve_fbo' when we use MSAA.
-	if (resolve_fbo != 0)
-		gl.bindFramebuffer(GL_READ_FRAMEBUFFER, resolve_fbo);
-	else
-		gl.bindFramebuffer(GL_FRAMEBUFFER, fbo);
-
-	glReadPixels(x, y, w, h, GL_RGBA, datatype, pixels);
-
-	GLuint prevfbo = current ? current->fbo : gl.getDefaultFBO();
-	gl.bindFramebuffer(GL_FRAMEBUFFER, prevfbo);
-
-	// The new ImageData now owns the pixel data, so we don't delete it here.
-	return image->newImageData(w, h, imageformat, pixels, true);
-}
-
-bool Canvas::resolveMSAA(bool restoreprev)
-{
-	if (resolve_fbo == 0 || msaa_buffer == 0)
-		return false;
-
-	OpenGL::TempDebugGroup debuggroup("Canvas MSAA resolve");
-
-	GLint w = width;
-	GLint h = height;
-
-	// Do the MSAA resolve by blitting the MSAA renderbuffer to the texture.
-	// For many of the MSAA extensions that add suffixes to the functions, we
-	// assign function pointers in OpenGL.cpp so we can call the core functions.
-
-	gl.bindFramebuffer(GL_READ_FRAMEBUFFER, fbo);
-	gl.bindFramebuffer(GL_DRAW_FRAMEBUFFER, resolve_fbo);
-
-	if (GLAD_APPLE_framebuffer_multisample)
-		glResolveMultisampleFramebufferAPPLE();
-	else
-		glBlitFramebuffer(0, 0, w, h, 0, 0, w, h, GL_COLOR_BUFFER_BIT, GL_NEAREST);
-
-	if (restoreprev)
-	{
-		GLuint fbo = current ? current->fbo : gl.getDefaultFBO();
-		gl.bindFramebuffer(GL_FRAMEBUFFER, fbo);
-	}
-
-	return true;
-}
-
 Canvas::Format Canvas::getSizedFormat(Canvas::Format format)
 {
 	switch (format)
@@ -949,7 +593,7 @@ bool Canvas::isFormatSupported(Canvas::Format format)
 
 	GLuint fbo = 0;
 	supported = (createFBO(fbo, texture) == GL_FRAMEBUFFER_COMPLETE);
-	glDeleteFramebuffers(1, &fbo);
+	gl.deleteFramebuffer(fbo);
 
 	gl.deleteTexture(texture);
 

src/modules/graphics/opengl/Canvas.h

@@ -82,26 +82,6 @@ public:
 	bool setWrap(const Texture::Wrap &w) override;
 	const void *getHandle() const override;
 
-	/**
-	 * @param canvases A list of other canvases to temporarily attach to this one,
-	 * to allow drawing to multiple canvases at once.
-	 **/
-	void startGrab(const std::vector<Canvas *> &canvases);
-	void startGrab();
-	void stopGrab(bool switchingToOtherCanvas = false);
-
-	/**
-	 * Create and attach a stencil buffer to this Canvas' framebuffer, if necessary.
-	 **/
-	bool checkCreateStencil();
-
-	love::image::ImageData *newImageData(love::image::Image *image, int x, int y, int w, int h);
-
-	inline const std::vector<Canvas *> &getAttachedCanvases() const
-	{
-		return attachedCanvases;
-	}
-
 	inline GLenum getStatus() const
 	{
 		return status;
@@ -117,19 +97,26 @@ public:
 		return actual_samples;
 	}
 
+	inline int getRequestedMSAA() const
+	{
+		return requested_samples;
+	}
+
+	inline ptrdiff_t getMSAAHandle() const
+	{
+		return msaa_buffer;
+	}
+
+	inline GLuint getFBO() const
+	{
+		return fbo;
+	}
+
 	static Format getSizedFormat(Format format);
 	static bool isSupported();
 	static bool isMultiFormatMultiCanvasSupported();
 	static bool isFormatSupported(Format format);
 
-	static Canvas *current;
-
-	// The viewport dimensions of the system (default) framebuffer.
-	static OpenGL::Viewport systemViewport;
-
-	// Whether the main screen should have linear -> sRGB conversions enabled.
-	static bool screenHasSRGB;
-
 	static int canvasCount;
 
 	static bool getConstant(const char *in, Format &out);
@@ -137,29 +124,20 @@ public:
 
 private:
 
-	void setupGrab();
-
-	bool createMSAAFBO(GLenum internalformat);
-	bool resolveMSAA(bool restoreprev);
-
 	void drawv(const Matrix4 &t, const Vertex *v);
 
 	static void convertFormat(Format format, GLenum &internalformat, GLenum &externalformat, GLenum &type);
 	static size_t getFormatBitsPerPixel(Format format);
 
 	GLuint fbo;
-	GLuint resolve_fbo;
 
 	GLuint texture;
 	GLuint msaa_buffer;
-	GLuint depth_stencil;
 
 	Format format;
 
 	GLenum status;
 
-	std::vector<Canvas *> attachedCanvases;
-
 	int requested_samples;
 	int actual_samples;
 

src/modules/graphics/opengl/Graphics.h

@@ -24,6 +24,7 @@
 // STD
 #include <stack>
 #include <vector>
+#include <unordered_map>
 
 // OpenGL
 #include "OpenGL.h"
@@ -35,8 +36,6 @@
 #include "image/Image.h"
 #include "image/ImageData.h"
 
-#include "window/Window.h"
-
 #include "video/VideoStream.h"
 
 #include "Font.h"
@@ -53,21 +52,63 @@
 
 namespace love
 {
+
+class Reference;
+
 namespace graphics
 {
 namespace opengl
 {
 
+struct PassInfo
+{
+	enum BeginAction
+	{
+		BEGIN_LOAD,
+		BEGIN_CLEAR,
+		BEGIN_DISCARD,
+	};
+
+	enum EndAction
+	{
+		END_STORE,
+		END_DISCARD,
+	};
+
+	struct ColorAttachment
+	{
+		Canvas *canvas = nullptr;
+		Colorf clearColor = Colorf(0.0f, 0.0f, 0.0f, 0.0f);
+		BeginAction beginAction = BEGIN_LOAD;
+	};
+
+	ColorAttachment colorAttachments[MAX_COLOR_RENDER_TARGETS];
+	int colorAttachmentCount = 0;
+
+	bool stencil = false;
+
+	bool addColorAttachment(const ColorAttachment &attachment)
+	{
+		if (colorAttachmentCount + 1 < MAX_COLOR_RENDER_TARGETS)
+		{
+			colorAttachments[colorAttachmentCount++] = attachment;
+			return true;
+		}
+
+		return false;
+	}
+};
+
 class Graphics : public love::graphics::Graphics
 {
 public:
 
-	struct OptionalColorf
-	{
-		float r, g, b, a;
-		bool enabled;
+	typedef void (*ScreenshotCallback)(love::image::ImageData *i, Reference *ref, void *ud);
 
-		Colorf toColor() const { return Colorf(r, g, b, a); }
+	struct ScreenshotInfo
+	{
+		ScreenshotCallback callback;
+		Reference *ref;
 	};
 
 	Graphics();
@@ -92,25 +133,19 @@ public:
 	 **/
 	void reset();
 
-	/**
-	 * Clears the screen to a specific color.
-	 **/
-	void clear(Colorf c);
+	void beginPass(PassInfo::BeginAction beginAction, Colorf clearColor);
+	void beginPass(const PassInfo &info);
 
-	/**
-	 * Clears each active canvas to a different color.
-	 **/
-	void clear(const std::vector<OptionalColorf> &colors);
+	void endPass();
+	void endPass(int sX, int sY, int sW, int sH, const ScreenshotInfo *info, void *screenshotCallbackData);
 
-	/**
-	 * Discards the contents of the screen.
-	 **/
-	void discard(const std::vector<bool> &colorbuffers, bool stencil);
+	const PassInfo &getActivePass() const;
+	virtual bool isPassActive() const;
 
 	/**
 	 * Flips buffers. (Rendered geometry is presented on screen).
 	 **/
-	void present();
+	void present(void *screenshotCallbackData);
 
 	/**
 	 * Gets the width of the current graphics viewport.
@@ -122,6 +157,9 @@ public:
 	 **/
 	int getHeight() const;
 
+	int getPassWidth() const;
+	int getPassHeight() const;
+
 	/**
 	 * True if a graphics viewport is set.
 	 **/
@@ -231,13 +269,6 @@ public:
 
 	Shader *getShader() const;
 
-	void setCanvas(Canvas *canvas);
-	void setCanvas(const std::vector<Canvas *> &canvases);
-	void setCanvas(const std::vector<StrongRef<Canvas>> &canvases);
-	void setCanvas();
-
-	std::vector<Canvas *> getCanvas() const;
-
 	/**
 	 * Sets the enabled color components when rendering.
 	 **/
@@ -330,6 +361,9 @@ public:
 	 **/
 	bool isWireframe() const;
 
+	void draw(Drawable *drawable, const Matrix4 &m);
+	void drawq(Texture *texture, Quad *quad, const Matrix4 &m);
+
 	/**
 	 * Draws text at the specified coordinates
 	 **/
@@ -422,12 +456,7 @@ public:
 	 **/
 	void polygon(DrawMode mode, const float *coords, size_t count);
 
-	/**
-	 * Creates a screenshot of the view and saves it to the default folder.
-	 * @param image The love.image module.
-	 * @param copyAlpha If the alpha channel should be copied or set to full opacity (1.0).
-	 **/
-	love::image::ImageData *newScreenshot(love::image::Image *image, bool copyAlpha = true);
+	void captureScreenshot(const ScreenshotInfo &info);
 
 	/**
 	 * Returns system-dependent renderer information.
@@ -488,8 +517,6 @@ private:
 		StrongRef<Font> font;
 		StrongRef<Shader> shader;
 
-		std::vector<StrongRef<Canvas>> canvases;
-
 		ColorMask colorMask = ColorMask(true, true, true, true);
 
 		bool wireframe = false;
@@ -500,19 +527,47 @@ private:
 		float defaultMipmapSharpness = 0.0f;
 	};
 
+	struct CurrentPass
+	{
+		PassInfo info;
+		bool active;
+	};
+
+	struct PassBufferInfo
+	{
+		bool stencil;
+		Canvas *canvases[MAX_COLOR_RENDER_TARGETS];
+	};
+
+	struct CachedRenderbuffer
+	{
+		int w;
+		int h;
+		int samples;
+		GLenum attachments[2];
+		GLuint renderbuffer;
+	};
+
 	void restoreState(const DisplayState &s);
 	void restoreStateChecked(const DisplayState &s);
 
+	void bindCachedFBOForPass(const PassInfo &pass);
+	void discard(OpenGL::FramebufferTarget target, const std::vector<bool> &colorbuffers, bool depthstencil);
+	GLuint attachCachedStencilBuffer(int w, int h, int samples);
+
 	void checkSetDefaultFont();
 
 	int calculateEllipsePoints(float rx, float ry) const;
 
-	StrongRef<love::window::Window> currentWindow;
-
 	StrongRef<Font> defaultFont;
 
 	std::vector<double> pixelSizeStack; // stores current size of a pixel (needed for line drawing)
 
+	std::vector<ScreenshotInfo> pendingScreenshotCallbacks;
+
+	std::unordered_map<uint32, GLuint> framebufferObjects;
+	std::vector<CachedRenderbuffer> stencilBuffers;
+
 	QuadIndices *quadIndices;
 
 	int width;
@@ -520,11 +575,17 @@ private:
 	bool created;
 	bool active;
 
+	bool canCaptureScreenshot;
+
+	CurrentPass currentPass;
+
 	bool writingToStencil;
 
 	std::vector<DisplayState> states;
 	std::vector<StackType> stackTypes; // Keeps track of the pushed stack types.
 
+	int renderPassCount;
+
 	static const size_t MAX_USER_STACK_DEPTH = 64;
 
 }; // Graphics

src/modules/graphics/opengl/OpenGL.cpp

@@ -23,7 +23,6 @@
 #include "OpenGL.h"
 
 #include "Shader.h"
-#include "Canvas.h"
 #include "common/Exception.h"
 
 // C++
@@ -135,6 +134,10 @@ void OpenGL::setupContext()
 	else
 		state.pointSize = 1.0f;
 
+	for (int i = 0; i < 2; i++)
+		state.boundFramebuffers[i] = std::numeric_limits<GLuint>::max();
+	bindFramebuffer(FRAMEBUFFER_ALL, getDefaultFBO());
+
 	if (GLAD_VERSION_3_0 || GLAD_ARB_framebuffer_sRGB || GLAD_EXT_framebuffer_sRGB
 		|| GLAD_EXT_sRGB_write_control)
 	{
@@ -283,7 +286,7 @@ void OpenGL::initMaxValues()
 		glGetIntegerv(GL_MAX_DRAW_BUFFERS, &maxdrawbuffers);
 	}
 
-	maxRenderTargets = std::min(maxattachments, maxdrawbuffers);
+	maxRenderTargets = std::max(std::min(maxattachments, maxdrawbuffers), 1);
 
 	if (GLAD_ES_VERSION_3_0 || GLAD_VERSION_3_0 || GLAD_ARB_framebuffer_object
 		|| GLAD_EXT_framebuffer_multisample || GLAD_APPLE_framebuffer_multisample
@@ -463,7 +466,7 @@ void OpenGL::useVertexAttribArrays(uint32 arraybits)
 		glVertexAttrib4f(ATTRIB_COLOR, 1.0f, 1.0f, 1.0f, 1.0f);
 }
 
-void OpenGL::setViewport(const OpenGL::Viewport &v)
+void OpenGL::setViewport(const OpenGL::Viewport &v, bool canvasActive)
 {
 	glViewport(v.x, v.y, v.w, v.h);
 	state.viewport = v;
@@ -471,7 +474,7 @@ void OpenGL::setViewport(const OpenGL::Viewport &v)
 	// glScissor starts from the lower left, so we compensate when setting the
 	// scissor. When the viewport is changed, we need to manually update the
 	// scissor again.
-	setScissor(state.scissor);
+	setScissor(state.scissor, canvasActive);
 }
 
 OpenGL::Viewport OpenGL::getViewport() const
@@ -479,9 +482,9 @@ OpenGL::Viewport OpenGL::getViewport() const
 	return state.viewport;
 }
 
-void OpenGL::setScissor(const OpenGL::Viewport &v)
+void OpenGL::setScissor(const OpenGL::Viewport &v, bool canvasActive)
 {
-	if (Canvas::current)
+	if (canvasActive)
 		glScissor(v.x, v.y, v.w, v.h);
 	else
 	{
@@ -526,12 +529,53 @@ bool OpenGL::hasFramebufferSRGB() const
 	return state.framebufferSRGBEnabled;
 }
 
-void OpenGL::bindFramebuffer(GLenum target, GLuint framebuffer)
+void OpenGL::bindFramebuffer(FramebufferTarget target, GLuint framebuffer)
 {
-	glBindFramebuffer(target, framebuffer);
+	bool bindingmodified = false;
+
+	if ((target & FRAMEBUFFER_DRAW) && state.boundFramebuffers[0] != framebuffer)
+	{
+		bindingmodified = true;
+		state.boundFramebuffers[0] = framebuffer;
+	}
+
+	if ((target & FRAMEBUFFER_READ) && state.boundFramebuffers[1] != framebuffer)
+	{
+		bindingmodified = true;
+		state.boundFramebuffers[1] = framebuffer;
+	}
+
+	if (bindingmodified)
+	{
+		GLenum gltarget = GL_FRAMEBUFFER;
+		if (target == FRAMEBUFFER_DRAW)
+			gltarget = GL_DRAW_FRAMEBUFFER;
+		else if (target == FRAMEBUFFER_READ)
+			gltarget = GL_READ_FRAMEBUFFER;
 
-	if (target == GL_FRAMEBUFFER)
-		++stats.framebufferBinds;
+		glBindFramebuffer(gltarget, framebuffer);
+	}
+}
+
+GLenum OpenGL::getFramebuffer(FramebufferTarget target) const
+{
+	if (target & FRAMEBUFFER_DRAW)
+		return state.boundFramebuffers[0];
+	else if (target & FRAMEBUFFER_READ)
+		return state.boundFramebuffers[1];
+	else
+		return 0;
+}
+
+void OpenGL::deleteFramebuffer(GLuint framebuffer)
+{
+	glDeleteFramebuffers(1, &framebuffer);
+
+	for (int i = 0; i < 2; i++)
+	{
+		if (state.boundFramebuffers[i] == framebuffer)
+			state.boundFramebuffers[i] = 0;
+	}
 }
 
 void OpenGL::useProgram(GLuint program)
@@ -680,7 +724,7 @@ int OpenGL::getMaxTextureSize() const
 
 int OpenGL::getMaxRenderTargets() const
 {
-	return maxRenderTargets;
+	return std::min(maxRenderTargets, MAX_COLOR_RENDER_TARGETS);
 }
 
 int OpenGL::getMaxRenderbufferSamples() const
@@ -739,6 +783,36 @@ const char *OpenGL::errorString(GLenum errorcode)
 	return text;
 }
 
+const char *OpenGL::framebufferStatusString(GLenum status)
+{
+	switch (status)
+	{
+	case GL_FRAMEBUFFER_COMPLETE:
+		return "complete (success)";
+	case GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT:
+		return "Texture format cannot be rendered to on this system.";
+	case GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT:
+		return "Error in graphics driver (missing render texture attachment)";
+	case GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER:
+		return "Error in graphics driver (incomplete draw buffer)";
+	case GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER:
+		return "Error in graphics driver (incomplete read buffer)";
+	case GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE:
+		return "Canvas with the specified MSAA count cannot be rendered to on this system.";
+	case GL_FRAMEBUFFER_UNSUPPORTED:
+		return "Renderable textures are unsupported";
+	default:
+		break;
+	}
+
+	static char text[64] = {};
+
+	memset(text, 0, sizeof(text));
+	sprintf(text, "0x%x", status);
+
+	return text;
+}
+
 const char *OpenGL::debugSeverityString(GLenum severity)
 {
 	switch (severity)

src/modules/graphics/opengl/OpenGL.h

@@ -104,6 +104,13 @@ public:
 		VENDOR_UNKNOWN
 	};
 
+	enum FramebufferTarget
+	{
+		FRAMEBUFFER_READ = (1 << 1),
+		FRAMEBUFFER_DRAW = (1 << 2),
+		FRAMEBUFFER_ALL  = (FRAMEBUFFER_READ | FRAMEBUFFER_DRAW),
+	};
+
 	// A rectangle representing an OpenGL viewport or a scissor box.
 	struct Viewport
 	{
@@ -173,7 +180,6 @@ public:
 	{
 		size_t textureMemory;
 		int    drawCalls;
-		int    framebufferBinds;
 		int    shaderSwitches;
 	} stats;
 
@@ -282,7 +288,7 @@ public:
 	 * Sets the OpenGL rendering viewport to the specified rectangle.
 	 * The y-coordinate starts at the top.
 	 **/
-	void setViewport(const Viewport &v);
+	void setViewport(const Viewport &v, bool canvasActive);
 
 	/**
 	 * Gets the current OpenGL rendering viewport rectangle.
@@ -293,7 +299,7 @@ public:
 	 * Sets the scissor box to the specified rectangle.
 	 * The y-coordinate starts at the top and is flipped internally.
 	 **/
-	void setScissor(const Viewport &v);
+	void setScissor(const Viewport &v, bool canvasActive);
 
 	/**
 	 * Gets the current scissor box (regardless of whether scissoring is enabled.)
@@ -323,7 +329,9 @@ public:
 	/**
 	 * Binds a Framebuffer Object to the specified target.
 	 **/
-	void bindFramebuffer(GLenum target, GLuint framebuffer);
+	void bindFramebuffer(FramebufferTarget target, GLuint framebuffer);
+	GLuint getFramebuffer(FramebufferTarget target) const;
+	void deleteFramebuffer(GLuint framebuffer);
 
 	/**
 	 * Calls glUseProgram.
@@ -413,6 +421,7 @@ public:
 	static GLint getGLWrapMode(Texture::WrapMode wmode);
 
 	static const char *errorString(GLenum errorcode);
+	static const char *framebufferStatusString(GLenum status);
 
 	// Get human-readable strings for debug info.
 	static const char *debugSeverityString(GLenum severity);
@@ -456,6 +465,8 @@ private:
 
 		float pointSize;
 
+		GLuint boundFramebuffers[2];
+
 		bool framebufferSRGBEnabled;
 
 		GLuint defaultTexture;

src/modules/graphics/opengl/Shader.cpp

@@ -22,7 +22,7 @@
 #include "common/config.h"
 
 #include "Shader.h"
-#include "Canvas.h"
+#include "Graphics.h"
 
 // C++
 #include <algorithm>
@@ -76,7 +76,7 @@ Shader::Shader(const ShaderSource &source)
 	, program(0)
 	, builtinUniforms()
 	, builtinAttributes()
-	, lastCanvas((Canvas *) -1)
+	, canvasWasActive(false)
 	, lastViewport()
 	, lastPointSize(0.0f)
 	, videoTextureUnits()
@@ -237,7 +237,7 @@ bool Shader::loadVolatile()
 	OpenGL::TempDebugGroup debuggroup("Shader load");
 
     // Recreating the shader program will invalidate uniforms that rely on these.
-    lastCanvas = (Canvas *) -1;
+	canvasWasActive = false;
     lastViewport = OpenGL::Viewport();
 
 	lastPointSize = -1.0f;
@@ -339,11 +339,11 @@ bool Shader::loadVolatile()
 
 void Shader::unloadVolatile()
 {
-	if (current == this)
-		gl.useProgram(0);
-
 	if (program != 0)
 	{
+		if (current == this)
+			gl.useProgram(0);
+
 		glDeleteProgram(program);
 		program = 0;
 	}
@@ -686,7 +686,10 @@ void Shader::checkSetScreenParams()
 {
 	OpenGL::Viewport view = gl.getViewport();
 
-	if (view == lastViewport && lastCanvas == Canvas::current)
+	auto gfx = Module::getInstance<Graphics>(Module::M_GRAPHICS);
+	bool canvasActive = gfx->getActivePass().colorAttachmentCount > 0;
+
+	if (view == lastViewport && canvasWasActive == canvasActive)
 		return;
 
 	// In the shader, we do pixcoord.y = gl_FragCoord.y * params.z + params.w.
@@ -697,7 +700,7 @@ void Shader::checkSetScreenParams()
 		0.0f, 0.0f,
 	};
 
-	if (Canvas::current != nullptr)
+	if (canvasActive)
 	{
 		// No flipping: pixcoord.y = gl_FragCoord.y * 1.0 + 0.0.
 		params[2] = 1.0f;
@@ -719,7 +722,7 @@ void Shader::checkSetScreenParams()
 		glUniform4fv(location, 1, params);
 	}
 
-	lastCanvas = Canvas::current;
+	canvasWasActive = canvasActive;
 	lastViewport = view;
 }
 

src/modules/graphics/opengl/Shader.h

@@ -41,8 +41,6 @@ namespace graphics
 namespace opengl
 {
 
-class Canvas;
-
 // A GLSL shader
 class Shader : public Object, public Volatile
 {
@@ -245,8 +243,7 @@ private:
 	// Uniform name to retainable objects
 	std::map<std::string, Object*> boundRetainables;
 
-	// Pointer to the active Canvas when the screen params were last checked.
-	Canvas *lastCanvas;
+	bool canvasWasActive;
 	OpenGL::Viewport lastViewport;
 
 	float lastPointSize;

src/modules/graphics/opengl/wrap_Canvas.cpp

@@ -33,55 +33,6 @@ Canvas *luax_checkcanvas(lua_State *L, int idx)
 	return luax_checktype<Canvas>(L, idx, GRAPHICS_CANVAS_ID);
 }
 
-int w_Canvas_renderTo(lua_State *L)
-{
-	Canvas *canvas = luax_checkcanvas(L, 1);
-	luaL_checktype(L, 2, LUA_TFUNCTION);
-
-	auto graphics = Module::getInstance<Graphics>(Module::M_GRAPHICS);
-
-	if (graphics)
-	{
-		// Save the current Canvas so we can restore it when we're done.
-		std::vector<Canvas *> oldcanvases = graphics->getCanvas();
-
-		for (Canvas *c : oldcanvases)
-			c->retain();
-
-		luax_catchexcept(L, [&](){ graphics->setCanvas(canvas); });
-
-		lua_settop(L, 2); // make sure the function is on top of the stack
-		int status = lua_pcall(L, 0, 0, 0);
-
-		graphics->setCanvas(oldcanvases);
-
-		for (Canvas *c : oldcanvases)
-			c->release();
-
-		if (status != 0)
-			return lua_error(L);
-	}
-
-	return 0;
-}
-
-int w_Canvas_newImageData(lua_State *L)
-{
-	Canvas *canvas = luax_checkcanvas(L, 1);
-	love::image::Image *image = luax_getmodule<love::image::Image>(L, MODULE_IMAGE_ID);
-	int x = (int) luaL_optnumber(L, 2, 0);
-	int y = (int) luaL_optnumber(L, 3, 0);
-	int w = (int) luaL_optnumber(L, 4, canvas->getWidth());
-	int h = (int) luaL_optnumber(L, 5, canvas->getHeight());
-
-	love::image::ImageData *img = nullptr;
-	luax_catchexcept(L, [&](){ img = canvas->newImageData(image, x, y, w, h); });
-
-	luax_pushtype(L, IMAGE_IMAGE_DATA_ID, img);
-	img->release();
-	return 1;
-}
-
 int w_Canvas_getFormat(lua_State *L)
 {
 	Canvas *canvas = luax_checkcanvas(L, 1);
@@ -103,8 +54,6 @@ int w_Canvas_getMSAA(lua_State *L)
 
 static const luaL_Reg w_Canvas_functions[] =
 {
-	{ "renderTo", w_Canvas_renderTo },
-	{ "newImageData", w_Canvas_newImageData },
 	{ "getFormat", w_Canvas_getFormat },
 	{ "getMSAA", w_Canvas_getMSAA },
 	{ 0, 0 }

src/modules/graphics/opengl/wrap_Graphics.cpp

@@ -27,6 +27,7 @@
 #include "filesystem/wrap_Filesystem.h"
 #include "video/VideoStream.h"
 #include "image/wrap_Image.h"
+#include "common/Reference.h"
 
 #include <cassert>
 #include <cstring>
@@ -60,117 +61,315 @@ int w_reset(lua_State *)
 	return 0;
 }
 
-int w_clear(lua_State *L)
+int w_present(lua_State *L)
 {
-	Colorf color;
+	luax_catchexcept(L, [&]() { instance()->present(L); });
+	return 0;
+}
+
+int w_isCreated(lua_State *L)
+{
+	luax_pushboolean(L, instance()->isCreated());
+	return 1;
+}
+
+int w_isActive(lua_State *L)
+{
+	luax_pushboolean(L, instance()->isActive());
+	return 1;
+}
+
+int w_isGammaCorrect(lua_State *L)
+{
+	luax_pushboolean(L, instance()->isGammaCorrect());
+	return 1;
+}
+
+int w_getWidth(lua_State *L)
+{
+	lua_pushinteger(L, instance()->getWidth());
+	return 1;
+}
+
+int w_getHeight(lua_State *L)
+{
+	lua_pushinteger(L, instance()->getHeight());
+	return 1;
+}
+
+int w_getDimensions(lua_State *L)
+{
+	lua_pushinteger(L, instance()->getWidth());
+	lua_pushinteger(L, instance()->getHeight());
+	return 2;
+}
+
+int w_getPassWidth(lua_State *L)
+{
+	lua_pushinteger(L, instance()->getPassWidth());
+	return 1;
+}
+
+int w_getPassHeight(lua_State *L)
+{
+	lua_pushinteger(L, instance()->getPassHeight());
+	return 1;
+}
+
+int w_getPassDimensions(lua_State *L)
+{
+	lua_pushinteger(L, instance()->getPassWidth());
+	lua_pushinteger(L, instance()->getPassHeight());
+	return 2;
+}
+
+static int w__beginPass(lua_State *L)
+{
+	int nextstartidx = 1;
 
 	if (lua_isnoneornil(L, 1))
-		color.set(0.0, 0.0, 0.0, 0.0);
-	else if (lua_istable(L, 1))
 	{
-		std::vector<Graphics::OptionalColorf> colors((size_t) lua_gettop(L));
+		luax_catchexcept(L, [&]() { instance()->beginPass(PassInfo::BEGIN_LOAD, Colorf()); });
+		nextstartidx = 1;
+	}
+	else if (lua_isnumber(L, 1))
+	{
+		Colorf c;
+		c.r = (float) luaL_checknumber(L, 1);
+		c.g = (float) luaL_checknumber(L, 2);
+		c.b = (float) luaL_checknumber(L, 3);
+
+		if (lua_isnumber(L, 4))
+		{
+			c.a = (float) lua_tonumber(L, 4);
+			nextstartidx = 5;
+		}
+		else
+		{
+			c.a = 1.0f;
+			nextstartidx = 4;
+		}
+
+		luax_catchexcept(L, [&]() { instance()->beginPass(PassInfo::BEGIN_CLEAR, c); });
+	}
+	else if (luax_istype(L, 1, GRAPHICS_CANVAS_ID))
+	{
+		PassInfo::ColorAttachment attachment;
+		attachment.canvas = luax_checkcanvas(L, 1);
+		attachment.beginAction = PassInfo::BEGIN_LOAD;
 
-		for (int i = 0; i < lua_gettop(L); i++)
+		if (lua_isnumber(L, 2))
 		{
-			if (lua_isnoneornil(L, i + 1) || luax_objlen(L, i + 1) == 0)
+			attachment.beginAction = PassInfo::BEGIN_CLEAR;
+			attachment.clearColor.r = (float) luaL_checknumber(L, 2);
+			attachment.clearColor.g = (float) luaL_checknumber(L, 3);
+			attachment.clearColor.b = (float) luaL_checknumber(L, 4);
+
+			if (lua_isnumber(L, 5))
 			{
-				colors[i].enabled = false;
-				continue;
+				attachment.clearColor.a = (float) lua_tonumber(L, 5);
+				nextstartidx = 6;
 			}
+			else
+			{
+				attachment.clearColor.a = 1.0f;
+				nextstartidx = 5;
+			}
+		}
+		else
+			nextstartidx = 2;
 
-			for (int j = 1; j <= 4; j++)
-				lua_rawgeti(L, i + 1, j);
-
-			colors[i].enabled = true;
-			colors[i].r = (float) luaL_checknumber(L, -4);
-			colors[i].g = (float) luaL_checknumber(L, -3);
-			colors[i].b = (float) luaL_checknumber(L, -2);
-			colors[i].a = (float) luaL_optnumber(L, -1, 1.0);
+		PassInfo info;
+		info.addColorAttachment(attachment);
 
-			lua_pop(L, 4);
+		if (lua_isboolean(L, nextstartidx))
+		{
+			info.stencil = luax_toboolean(L, nextstartidx);
+			nextstartidx++;
 		}
+		else
+			info.stencil = false;
 
-		luax_catchexcept(L, [&]() { instance()->clear(colors); });
-		return 0;
+		luax_catchexcept(L, [&]() { instance()->beginPass(info); });
 	}
 	else
 	{
-		color.r = (float) luaL_checknumber(L, 1);
-		color.g = (float) luaL_checknumber(L, 2);
-		color.b = (float) luaL_checknumber(L, 3);
-		color.a = (float) luaL_optnumber(L, 4, 1.0);
+		luaL_checktype(L, 1, LUA_TTABLE);
+
+		int nattachments = std::max((int) luax_objlen(L, 1), 1);
+
+		if (nattachments > MAX_COLOR_RENDER_TARGETS)
+			return luaL_error(L, "Cannot render to %d Canvases at once!", nattachments);
+
+		PassInfo info;
+
+		for (int i = 1; i <= nattachments; i++)
+		{
+			lua_rawgeti(L, 1, i);
+			luaL_checktype(L, -1, LUA_TTABLE);
+
+			PassInfo::ColorAttachment attachment;
+			attachment.beginAction = PassInfo::BEGIN_LOAD;
+
+			lua_rawgeti(L, -1, 1);
+			attachment.canvas = luax_checkcanvas(L, -1);
+
+			lua_rawgeti(L, -2, 2);
+			if (!lua_isnoneornil(L, -1))
+			{
+				attachment.beginAction = PassInfo::BEGIN_CLEAR;
+
+				for (int j = 3; j < 6; j++)
+					lua_rawgeti(L, -j, j);
+
+				attachment.clearColor.r = (float) luaL_checknumber(L, -4);
+				attachment.clearColor.g = (float) luaL_checknumber(L, -3);
+				attachment.clearColor.b = (float) luaL_checknumber(L, -2);
+				attachment.clearColor.a = (float) luaL_optnumber(L, -1, 1.0);
+			}
+
+			lua_pop(L, 2 + (attachment.beginAction == PassInfo::BEGIN_CLEAR ? 4 : 1));
+
+			info.addColorAttachment(attachment);
+		}
+
+		info.stencil = luax_boolflag(L, 1, "stencil", false);
+
+		luax_catchexcept(L, [&]() { instance()->beginPass(info); });
+
+		nextstartidx = 2;
 	}
 
-	luax_catchexcept(L, [&]() { instance()->clear(color); });
+	return nextstartidx;
+}
+
+int w_beginPass(lua_State *L)
+{
+	w__beginPass(L);
 	return 0;
 }
 
-int w_discard(lua_State *L)
+static void screenshotCallback(love::image::ImageData *i, Reference *ref, void *gd)
 {
-	std::vector<bool> colorbuffers;
+	if (i != nullptr)
+	{
+		lua_State *L = (lua_State *) gd;
+		ref->push(L);
+		delete ref;
+		luax_pushtype(L, IMAGE_IMAGE_DATA_ID, i);
+		lua_call(L, 1, 0);
+	}
+	else
+		delete ref;
+}
 
-	if (lua_istable(L, 1))
+static int w__endPass(lua_State *L, int startidx)
+{
+	if (lua_isnoneornil(L, startidx))
 	{
-		for (size_t i = 1; i <= luax_objlen(L, 1); i++)
-		{
-			lua_rawgeti(L, 1, i);
-			colorbuffers.push_back(luax_optboolean(L, -1, true));
-			lua_pop(L, 1);
-		}
+		luax_catchexcept(L, []() { instance()->endPass(); });
 	}
 	else
 	{
-		bool discardcolor = luax_optboolean(L, 1, true);
-		size_t numbuffers = std::max((size_t) 1, instance()->getCanvas().size());
-		colorbuffers = std::vector<bool>(numbuffers, discardcolor);
+		int x, y, w, h;
+
+		if (lua_isnumber(L, startidx))
+		{
+			x = (int) luaL_checknumber(L, 1);
+			y = (int) luaL_checknumber(L, 2);
+			w = (int) luaL_checknumber(L, 3);
+			h = (int) luaL_checknumber(L, 4);
+			startidx += 4;
+		}
+		else
+		{
+			x = 0;
+			y = 0;
+			w = instance()->getPassWidth();
+			h = instance()->getPassHeight();
+		}
+
+		luaL_checktype(L, startidx, LUA_TFUNCTION);
+
+		Graphics::ScreenshotInfo info;
+		info.callback = screenshotCallback;
+
+		lua_pushvalue(L, startidx);
+		info.ref = luax_refif(L, LUA_TFUNCTION);
+		lua_pop(L, 1);
+
+		luax_catchexcept(L,
+			[&]() { instance()->endPass(x, y, w, h, &info, L); },
+			[&](bool except) { if (except) delete info.ref; }
+		);
 	}
 
-	bool stencil = luax_optboolean(L, 2, true);
-	instance()->discard(colorbuffers, stencil);
 	return 0;
 }
 
-int w_present(lua_State *)
+int w_endPass(lua_State *L)
 {
-	instance()->present();
-	return 0;
+	return w__endPass(L, 1);
 }
 
-int w_isCreated(lua_State *L)
+int w_renderPass(lua_State *L)
 {
-	luax_pushboolean(L, instance()->isCreated());
-	return 1;
-}
+	int startidx = w__beginPass(L);
 
-int w_isActive(lua_State *L)
-{
-	luax_pushboolean(L, instance()->isActive());
-	return 1;
-}
+	if (lua_type(L, startidx) != LUA_TFUNCTION)
+	{
+		w__endPass(L, startidx + 1);
+		luaL_checktype(L, startidx, LUA_TFUNCTION);
+		return 0;
+	}
 
-int w_isGammaCorrect(lua_State *L)
-{
-	luax_pushboolean(L, instance()->isGammaCorrect());
-	return 1;
+	int nargs = lua_gettop(L) - startidx;
+	int status = lua_pcall(L, nargs, 0, 0);
+
+	w__endPass(L, startidx + 1);
+
+	if (status != 0)
+		return lua_error(L);
+
+	return 0;
 }
 
-int w_getWidth(lua_State *L)
+int w_isPassActive(lua_State *L)
 {
-	lua_pushinteger(L, instance()->getWidth());
+	luax_pushboolean(L, instance()->isPassActive());
 	return 1;
 }
 
-int w_getHeight(lua_State *L)
+int w_getPassCanvases(lua_State *L)
 {
-	lua_pushinteger(L, instance()->getHeight());
-	return 1;
+	if (!instance()->isPassActive())
+		return 0;
+
+	const PassInfo &info = instance()->getActivePass();
+
+	for (const auto &attachment : info.colorAttachments)
+		luax_pushtype(L, GRAPHICS_CANVAS_ID, attachment.canvas);
+
+	return info.colorAttachmentCount;
 }
 
-int w_getDimensions(lua_State *L)
+int w_captureScreenshot(lua_State *L)
 {
-	lua_pushinteger(L, instance()->getWidth());
-	lua_pushinteger(L, instance()->getHeight());
-	return 2;
+	luaL_checktype(L, 1, LUA_TFUNCTION);
+
+	Graphics::ScreenshotInfo info;
+	info.callback = screenshotCallback;
+
+	lua_pushvalue(L, 1);
+	info.ref = luax_refif(L, LUA_TFUNCTION);
+	lua_pop(L, 1);
+
+	luax_catchexcept(L,
+		[&]() { instance()->captureScreenshot(info); },
+		[&](bool except) { if (except) delete info.ref; }
+	);
+
+	return 0;
 }
 
 int w_setScissor(lua_State *L)
@@ -243,13 +442,13 @@ int w_stencil(lua_State *L)
 	if (lua_toboolean(L, 4) == 0)
 		instance()->clearStencil();
 
-	instance()->drawToStencilBuffer(action, stencilvalue);
+	luax_catchexcept(L, [&](){ instance()->drawToStencilBuffer(action, stencilvalue); });
 
 	// Call stencilfunc()
 	lua_pushvalue(L, 1);
 	lua_call(L, 0, 0);
 
-	instance()->stopDrawToStencilBuffer();
+	luax_catchexcept(L, [&](){ instance()->stopDrawToStencilBuffer(); });
 	return 0;
 }
 
@@ -268,7 +467,7 @@ int w_setStencilTest(lua_State *L)
 		comparevalue = (int) luaL_checknumber(L, 2);
 	}
 
-	instance()->setStencilTest(compare, comparevalue);
+	luax_catchexcept(L, [&](){ instance()->setStencilTest(compare, comparevalue); });
 	return 0;
 }
 
@@ -1246,79 +1445,6 @@ int w_isWireframe(lua_State *L)
 	return 1;
 }
 
-int w_newScreenshot(lua_State *L)
-{
-	love::image::Image *image = luax_getmodule<love::image::Image>(L, MODULE_IMAGE_ID);
-	bool copyAlpha = luax_optboolean(L, 1, false);
-	love::image::ImageData *i = 0;
-
-	luax_catchexcept(L, [&](){ i = instance()->newScreenshot(image, copyAlpha); });
-
-	luax_pushtype(L, IMAGE_IMAGE_DATA_ID, i);
-	i->release();
-	return 1;
-}
-
-int w_setCanvas(lua_State *L)
-{
-	// Disable stencil writes.
-	instance()->stopDrawToStencilBuffer();
-
-	// called with none -> reset to default buffer
-	if (lua_isnoneornil(L, 1))
-	{
-		instance()->setCanvas();
-		return 0;
-	}
-
-	bool is_table = lua_istable(L, 1);
-	std::vector<Canvas *> canvases;
-
-	if (is_table)
-	{
-		for (int i = 1; i <= (int) luax_objlen(L, 1); i++)
-		{
-			lua_rawgeti(L, 1, i);
-			canvases.push_back(luax_checkcanvas(L, -1));
-			lua_pop(L, 1);
-		}
-	}
-	else
-	{
-		for (int i = 1; i <= lua_gettop(L); i++)
-			canvases.push_back(luax_checkcanvas(L, i));
-	}
-
-	luax_catchexcept(L, [&]() {
-		if (canvases.size() > 0)
-			instance()->setCanvas(canvases);
-		else
-			instance()->setCanvas();
-	});
-
-	return 0;
-}
-
-int w_getCanvas(lua_State *L)
-{
-	const std::vector<Canvas *> canvases = instance()->getCanvas();
-	int n = 0;
-
-	for (Canvas *c : canvases)
-	{
-		luax_pushtype(L, GRAPHICS_CANVAS_ID, c);
-		n++;
-	}
-
-	if (n == 0)
-	{
-		lua_pushnil(L);
-		n = 1;
-	}
-
-	return n;
-}
-
 int w_setShader(lua_State *L)
 {
 	if (lua_isnoneornil(L,1))
@@ -1497,8 +1623,8 @@ int w_getStats(lua_State *L)
 	lua_pushinteger(L, stats.drawCalls);
 	lua_setfield(L, -2, "drawcalls");
 
-	lua_pushinteger(L, stats.canvasSwitches);
-	lua_setfield(L, -2, "canvasswitches");
+	lua_pushinteger(L, stats.renderPasses);
+	lua_setfield(L, -2, "renderpasses");
 
 	lua_pushinteger(L, stats.shaderSwitches);
 	lua_setfield(L, -2, "shaderswitches");
@@ -1555,9 +1681,9 @@ int w_draw(lua_State *L)
 
 	luax_catchexcept(L, [&]() {
 		if (texture && quad)
-			texture->drawq(quad, m);
+			instance()->drawq(texture, quad, m);
 		else if (drawable)
-			drawable->draw(m);
+			instance()->draw(drawable, m);
 	});
 
 	return 0;
@@ -1698,11 +1824,14 @@ int w_points(lua_State *L)
 			coords[i] = luax_tofloat(L, i + 1);
 	}
 
-	instance()->points(coords, colors, numpoints);
-
-	delete[] coords;
-	if (colors)
-		delete[] colors;
+	luax_catchexcept(L,
+		[&](){ instance()->points(coords, colors, numpoints); },
+		[&](bool) {
+			delete[] coords;
+			if (colors)
+				delete[] colors;
+		}
+	);
 
 	return 0;
 }
@@ -1738,9 +1867,11 @@ int w_line(lua_State *L)
 			coords[i] = luax_tofloat(L, i + 1);
 	}
 
-	instance()->polyline(coords, args);
+	luax_catchexcept(L,
+		[&](){ instance()->polyline(coords, args); },
+		[&](bool) { delete[] coords; }
+	);
 
-	delete[] coords;
 	return 0;
 }
 
@@ -1766,11 +1897,11 @@ int w_rectangle(lua_State *L)
 	float ry = (float)luaL_optnumber(L, 7, rx);
 
 	if (lua_isnoneornil(L, 8))
-		instance()->rectangle(mode, x, y, w, h, rx, ry);
+		luax_catchexcept(L, [&](){ instance()->rectangle(mode, x, y, w, h, rx, ry); });
 	else
 	{
 		int points = (int) luaL_checknumber(L, 8);
-		instance()->rectangle(mode, x, y, w, h, rx, ry, points);
+		luax_catchexcept(L, [&](){ instance()->rectangle(mode, x, y, w, h, rx, ry, points); });
 	}
 
 	return 0;
@@ -1788,11 +1919,11 @@ int w_circle(lua_State *L)
 	float radius = (float)luaL_checknumber(L, 4);
 
 	if (lua_isnoneornil(L, 5))
-		instance()->circle(mode, x, y, radius);
+		luax_catchexcept(L, [&](){ instance()->circle(mode, x, y, radius); });
 	else
 	{
 		int points = (int) luaL_checknumber(L, 5);
-		instance()->circle(mode, x, y, radius, points);
+		luax_catchexcept(L, [&](){ instance()->circle(mode, x, y, radius, points); });
 	}
 
 	return 0;
@@ -1811,11 +1942,11 @@ int w_ellipse(lua_State *L)
 	float b = (float)luaL_optnumber(L, 5, a);
 
 	if (lua_isnoneornil(L, 6))
-		instance()->ellipse(mode, x, y, a, b);
+		luax_catchexcept(L, [&](){ instance()->ellipse(mode, x, y, a, b); });
 	else
 	{
 		int points = (int) luaL_checknumber(L, 6);
-		instance()->ellipse(mode, x, y, a, b, points);
+		luax_catchexcept(L, [&](){ instance()->ellipse(mode, x, y, a, b, points); });
 	}
 
 	return 0;
@@ -1848,11 +1979,11 @@ int w_arc(lua_State *L)
 	float angle2 = (float) luaL_checknumber(L, startidx + 4);
 
 	if (lua_isnoneornil(L, startidx + 5))
-		instance()->arc(drawmode, arcmode, x, y, radius, angle1, angle2);
+		luax_catchexcept(L, [&](){ instance()->arc(drawmode, arcmode, x, y, radius, angle1, angle2); });
 	else
 	{
 		int points = (int) luaL_checknumber(L, startidx + 5);
-		instance()->arc(drawmode, arcmode, x, y, radius, angle1, angle2, points);
+		luax_catchexcept(L, [&](){ instance()->arc(drawmode, arcmode, x, y, radius, angle1, angle2, points); });
 	}
 
 	return 0;
@@ -1900,8 +2031,11 @@ int w_polygon(lua_State *L)
 	// make a closed loop
 	coords[args]   = coords[0];
 	coords[args+1] = coords[1];
-	instance()->polygon(mode, coords, args+2);
-	delete[] coords;
+
+	luax_catchexcept(L,
+		[&](){ instance()->polygon(mode, coords, args+2); },
+		[&](bool) { delete[] coords; }
+	);
 
 	return 0;
 }
@@ -1987,8 +2121,6 @@ int w_inverseTransformPoint(lua_State *L)
 static const luaL_Reg functions[] =
 {
 	{ "reset", w_reset },
-	{ "clear", w_clear },
-	{ "discard", w_discard },
 	{ "present", w_present },
 
 	{ "newImage", w_newImage },
@@ -2030,9 +2162,6 @@ static const luaL_Reg functions[] =
 	{ "getPointSize", w_getPointSize },
 	{ "setWireframe", w_setWireframe },
 	{ "isWireframe", w_isWireframe },
-	{ "newScreenshot", w_newScreenshot },
-	{ "setCanvas", w_setCanvas },
-	{ "getCanvas", w_getCanvas },
 
 	{ "setShader", w_setShader },
 	{ "getShader", w_getShader },
@@ -2046,6 +2175,14 @@ static const luaL_Reg functions[] =
 	{ "getSystemLimits", w_getSystemLimits },
 	{ "getStats", w_getStats },
 
+	{ "beginPass", w_beginPass },
+	{ "endPass", w_endPass },
+	{ "renderPass", w_renderPass },
+	{ "isPassActive", w_isPassActive },
+	{ "getPassCanvases", w_getPassCanvases },
+
+	{ "captureScreenshot", w_captureScreenshot },
+
 	{ "draw", w_draw },
 
 	{ "print", w_print },
@@ -2057,6 +2194,9 @@ static const luaL_Reg functions[] =
 	{ "getWidth", w_getWidth },
 	{ "getHeight", w_getHeight },
 	{ "getDimensions", w_getDimensions },
+	{ "getPassWidth", w_getPassWidth },
+	{ "getPassHeight", w_getPassHeight },
+	{ "getPassDimensions", w_getPassDimensions },
 
 	{ "setScissor", w_setScissor },
 	{ "intersectScissor", w_intersectScissor },

src/modules/window/Window.h

@@ -32,6 +32,12 @@
 
 namespace love
 {
+
+namespace graphics
+{
+class Graphics;
+}
+
 namespace window
 {
 
@@ -108,6 +114,8 @@ public:
 	// Implements Module.
 	virtual ModuleType getModuleType() const { return M_WINDOW; }
 
+	virtual void setGraphics(graphics::Graphics *graphics) = 0;
+
 	virtual bool setWindow(int width = 800, int height = 600, WindowSettings *settings = nullptr) = 0;
 	virtual void getWindow(int &width, int &height, WindowSettings &settings) = 0;
 

src/modules/window/sdl/Window.cpp

@@ -79,9 +79,16 @@ Window::~Window()
 {
 	close();
 
+	graphics.set(nullptr);
+
 	SDL_QuitSubSystem(SDL_INIT_VIDEO);
 }
 
+void Window::setGraphics(graphics::Graphics *graphics)
+{
+	this->graphics.set(graphics);
+}
+
 void Window::setGLFramebufferAttributes(int msaa, bool sRGB)
 {
 	// Set GL window / framebuffer attributes.
@@ -401,6 +408,12 @@ bool Window::createWindowAndContext(int x, int y, int w, int h, Uint32 windowfla
 
 bool Window::setWindow(int width, int height, WindowSettings *settings)
 {
+	if (!graphics.get())
+		graphics.set(Module::getInstance<graphics::Graphics>(Module::M_GRAPHICS));
+
+	if (graphics.get() && graphics->isPassActive())
+		throw love::Exception("setMode cannot be called while a render pass is active in love.graphics.");
+
 	WindowSettings f;
 
 	if (settings)
@@ -507,9 +520,8 @@ bool Window::setWindow(int width, int height, WindowSettings *settings)
 
 	updateSettings(f, false);
 
-	auto gfx = Module::getInstance<graphics::Graphics>(Module::M_GRAPHICS);
-	if (gfx != nullptr)
-		gfx->setMode(pixelWidth, pixelHeight);
+	if (graphics.get())
+		graphics->setMode(pixelWidth, pixelHeight);
 
 #ifdef LOVE_ANDROID
 	love::android::setImmersive(f.fullscreen);
@@ -528,9 +540,8 @@ bool Window::onSizeChanged(int width, int height)
 
 	SDL_GL_GetDrawableSize(window, &pixelWidth, &pixelHeight);
 
-	auto gfx = Module::getInstance<graphics::Graphics>(Module::M_GRAPHICS);
-	if (gfx != nullptr)
-		gfx->setViewportSize(pixelWidth, pixelHeight);
+	if (graphics.get())
+		graphics->setViewportSize(pixelWidth, pixelHeight);
 
 	return true;
 }
@@ -596,13 +607,9 @@ void Window::updateSettings(const WindowSettings &newsettings, bool updateGraphi
 	// May be 0 if the refresh rate can't be determined.
 	settings.refreshrate = (double) dmode.refresh_rate;
 
-	if (updateGraphicsViewport)
-	{
-		// Update the viewport size now instead of waiting for event polling.
-		auto gfx = Module::getInstance<graphics::Graphics>(Module::M_GRAPHICS);
-		if (gfx != nullptr)
-			gfx->setViewportSize(pixelWidth, pixelHeight);
-	}
+	// Update the viewport size now instead of waiting for event polling.
+	if (updateGraphicsViewport && graphics.get())
+		graphics->setViewportSize(pixelWidth, pixelHeight);
 }
 
 void Window::getWindow(int &width, int &height, WindowSettings &newsettings)
@@ -618,9 +625,13 @@ void Window::getWindow(int &width, int &height, WindowSettings &newsettings)
 
 void Window::close()
 {
-	auto gfx = Module::getInstance<graphics::Graphics>(Module::M_GRAPHICS);
-	if (gfx != nullptr)
-		gfx->unSetMode();
+	if (graphics.get())
+	{
+		if (graphics->isPassActive())
+			throw love::Exception("close cannot be called while a render pass is active in love.graphics.");
+
+		graphics->unSetMode();
+	}
 
 	if (context)
 	{
@@ -646,6 +657,9 @@ bool Window::setFullscreen(bool fullscreen, Window::FullscreenType fstype)
 	if (!window)
 		return false;
 
+	if (graphics.get() && graphics->isPassActive())
+		throw love::Exception("setFullscreen cannot be called while a render pass is active in love.graphics.");
+
 	WindowSettings newsettings = settings;
 	newsettings.fullscreen = fullscreen;
 	newsettings.fstype = fstype;

src/modules/window/sdl/Window.h

@@ -41,6 +41,8 @@ public:
 	Window();
 	~Window();
 
+	void setGraphics(graphics::Graphics *graphics);
+
 	bool setWindow(int width = 800, int height = 600, WindowSettings *settings = nullptr);
 	void getWindow(int &width, int &height, WindowSettings &settings);
 
@@ -149,6 +151,8 @@ private:
 	bool hasSDL203orEarlier;
 	ContextAttribs contextAttribs;
 
+	StrongRef<graphics::Graphics> graphics;
+
 }; // Window
 
 } // sdl

src/modules/window/wrap_Window.cpp

@@ -119,7 +119,7 @@ int w_setMode(lua_State *L)
 
 	if (lua_isnoneornil(L, 3))
 	{
-		luax_pushboolean(L, instance()->setWindow(w, h, nullptr));
+		luax_catchexcept(L, [&](){ luax_pushboolean(L, instance()->setWindow(w, h, nullptr)); });
 		return 1;
 	}
 
@@ -266,10 +266,12 @@ int w_setFullscreen(lua_State *L)
 		return luaL_error(L, "Invalid fullscreen type: %s", typestr);
 
 	bool success = false;
-	if (fstype == Window::FULLSCREEN_MAX_ENUM)
-		success = instance()->setFullscreen(fullscreen);
-	else
-		success = instance()->setFullscreen(fullscreen, fstype);
+	luax_catchexcept(L, [&]() {
+		if (fstype == Window::FULLSCREEN_MAX_ENUM)
+			success = instance()->setFullscreen(fullscreen);
+		else
+			success = instance()->setFullscreen(fullscreen, fstype);
+	});
 
 	luax_pushboolean(L, success);
 	return 1;
@@ -296,9 +298,9 @@ int w_isOpen(lua_State *L)
 	return 1;
 }
 
-int w_close(lua_State * /*L*/)
+int w_close(lua_State *L)
 {
-	instance()->close();
+	luax_catchexcept(L, [&]() { instance()->close(); });
 	return 0;
 }
 

src/scripts/boot.lua

@@ -545,9 +545,14 @@ function love.run()
 		if love.update then love.update(dt) end -- will pass 0 if love.timer is disabled
 
 		if love.graphics and love.graphics.isActive() then
-			love.graphics.clear(love.graphics.getBackgroundColor())
 			love.graphics.origin()
+
+			if love.drawpasses then love.drawpasses() end
+
+			love.graphics.beginPass(love.graphics.getBackgroundColor())
 			if love.draw then love.draw() end
+			love.graphics.endPass()
+
 			love.graphics.present()
 		end
 
@@ -598,15 +603,18 @@ function love.errhand(msg)
 		end
 	end
 	if love.audio then love.audio.stop() end
+
 	love.graphics.reset()
+	if love.graphics.isPassActive() then
+		love.graphics.endPass()
+	end
+
 	local font = love.graphics.setNewFont(math.floor(love.window.toPixels(14)))
 
-	love.graphics.setBackgroundColor(89/255, 157/255, 220/255)
 	love.graphics.setColor(1, 1, 1, 1)
 
 	local trace = debug.traceback()
 
-	love.graphics.clear(love.graphics.getBackgroundColor())
 	love.graphics.origin()
 
 	local err = {}
@@ -628,9 +636,7 @@ function love.errhand(msg)
 
 	local function draw()
 		local pos = love.window.toPixels(70)
-		love.graphics.clear(love.graphics.getBackgroundColor())
 		love.graphics.printf(p, pos, pos, love.graphics.getWidth() - pos)
-		love.graphics.present()
 	end
 
 	while true do
@@ -652,7 +658,8 @@ function love.errhand(msg)
 			end
 		end
 
-		draw()
+		love.graphics.renderPass(89/255, 157/255, 220/255, draw)
+		love.graphics.present()
 
 		if love.timer then
 			love.timer.sleep(0.1)

src/scripts/boot.lua.h

@@ -1005,14 +1005,19 @@ const unsigned char boot_lua[] =
 	0x09, 0x09, 0x69, 0x66, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 
 	0x20, 0x61, 0x6e, 0x64, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 
 	0x2e, 0x69, 0x73, 0x41, 0x63, 0x74, 0x69, 0x76, 0x65, 0x28, 0x29, 0x20, 0x74, 0x68, 0x65, 0x6e, 0x0a,
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-	0x72, 0x28, 0x29, 0x29, 0x0a,
 	0x09, 0x09, 0x09, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 0x6f, 
 	0x72, 0x69, 0x67, 0x69, 0x6e, 0x28, 0x29, 0x0a,
+	0x09, 0x09, 0x09, 0x69, 0x66, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x64, 0x72, 0x61, 0x77, 0x70, 0x61, 0x73, 
+	0x73, 0x65, 0x73, 0x20, 0x74, 0x68, 0x65, 0x6e, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x64, 0x72, 0x61, 0x77, 
+	0x70, 0x61, 0x73, 0x73, 0x65, 0x73, 0x28, 0x29, 0x20, 0x65, 0x6e, 0x64, 0x0a,
+	0x09, 0x09, 0x09, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 0x62, 
+	0x65, 0x67, 0x69, 0x6e, 0x50, 0x61, 0x73, 0x73, 0x28, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 
+	0x68, 0x69, 0x63, 0x73, 0x2e, 0x67, 0x65, 0x74, 0x42, 0x61, 0x63, 0x6b, 0x67, 0x72, 0x6f, 0x75, 0x6e, 0x64, 
+	0x43, 0x6f, 0x6c, 0x6f, 0x72, 0x28, 0x29, 0x29, 0x0a,
 	0x09, 0x09, 0x09, 0x69, 0x66, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x64, 0x72, 0x61, 0x77, 0x20, 0x74, 0x68, 
 	0x65, 0x6e, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x64, 0x72, 0x61, 0x77, 0x28, 0x29, 0x20, 0x65, 0x6e, 0x64, 0x0a,
+	0x09, 0x09, 0x09, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 0x65, 
+	0x6e, 0x64, 0x50, 0x61, 0x73, 0x73, 0x28, 0x29, 0x0a,
 	0x09, 0x09, 0x09, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 0x70, 
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 	0x09, 0x09, 0x65, 0x6e, 0x64, 0x0a,
@@ -1098,23 +1103,21 @@ const unsigned char boot_lua[] =
 	0x29, 0x20, 0x65, 0x6e, 0x64, 0x0a,
 	0x09, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 0x72, 0x65, 0x73, 
 	0x65, 0x74, 0x28, 0x29, 0x0a,
+	0x09, 0x69, 0x66, 0x20, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 
+	0x69, 0x73, 0x50, 0x61, 0x73, 0x73, 0x41, 0x63, 0x74, 0x69, 0x76, 0x65, 0x28, 0x29, 0x20, 0x74, 0x68, 0x65, 
+	0x6e, 0x0a,
+	0x09, 0x09, 0x6c, 0x6f, 0x76, 0x65, 0x2e, 0x67, 0x72, 0x61, 0x70, 0x68, 0x69, 0x63, 0x73, 0x2e, 0x65, 0x6e, 
+	0x64, 0x50, 0x61, 0x73, 0x73, 0x28, 0x29, 0x0a,
+	0x09, 0x65, 0x6e, 0x64, 0x0a,
 	0x09, 0x6c, 0x6f, 0x63, 0x61, 0x6c, 0x20, 0x66, 0x6f, 0x6e, 0x74, 0x20, 0x3d, 0x20, 0x6c, 0x6f, 0x76, 0x65, 
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 	0x2e, 0x77, 0x69, 0x6e, 0x64, 0x6f, 0x77, 0x2e, 0x74, 0x6f, 0x50, 0x69, 0x78, 0x65, 0x6c, 0x73, 0x28, 0x31, 
 	0x34, 0x29, 0x29, 0x29, 0x0a,
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@@ -1148,16 +1151,10 @@ const unsigned char boot_lua[] =
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@@ -1194,7 +1191,12 @@ const unsigned char boot_lua[] =
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