Merge branch 'dev' into working

README.md

@@ -20,10 +20,10 @@ by Jorge L. "VinoBS" Rodriguez, and stb_sprintf by Jeff Roberts.
 
 library    | lastest version | category | LoC | description
 --------------------- | ---- | -------- | --- | --------------------------------
-**[stb_vorbis.c](stb_vorbis.c)** | 1.21 | audio | 5569 | decode ogg vorbis files from file/memory to float/16-bit signed output
-**[stb_image.h](stb_image.h)** | 2.26 | graphics | 7762 | image loading/decoding from file/memory: JPG, PNG, TGA, BMP, PSD, GIF, HDR, PIC
+**[stb_vorbis.c](stb_vorbis.c)** | 1.20 | audio | 5563 | decode ogg vorbis files from file/memory to float/16-bit signed output
+**[stb_image.h](stb_image.h)** | 2.26 | graphics | 7762 | image loading/decoding from file/memory: JPG, PNG, TGA, BMP, PSD, GIF, HDR, PIC, PNM
 **[stb_truetype.h](stb_truetype.h)** | 1.24 | graphics | 5011 | parse, decode, and rasterize characters from truetype fonts
-**[stb_image_write.h](stb_image_write.h)** | 1.15 | graphics | 1690 | image writing to disk: PNG, TGA, BMP
+**[stb_image_write.h](stb_image_write.h)** | 1.15 | graphics | 1690 | image writing to disk: PNG, TGA, BMP, JPG, HDR
 **[stb_image_resize.h](stb_image_resize.h)** | 0.96 | graphics | 2631 | resize images larger/smaller with good quality
 **[stb_rect_pack.h](stb_rect_pack.h)** | 1.00 | graphics | 628 | simple 2D rectangle packer with decent quality
 **[stb_ds.h](stb_ds.h)** | 0.66 | utility | 1893 | typesafe dynamic array and hash tables for C, will compile in C++
@@ -49,6 +49,24 @@ Total lines of C code: 56530
 FAQ
 ---
 
+#### How do I use these libraries?
+
+The idea behind single-header file libraries is that they're easy to distribute and deploy
+because all the code is contained in a single file. By default, the .h files in here act as
+their own header files, i.e. they declare the functions contained in the file but don't
+actually result in any code getting compiled.
+
+So in addition, you should select _exactly one_ C/C++ source file that actually instantiates
+the code, preferably a file you're not editing frequently. This file should define a
+specific macro (this is documented per-library) to actually enable the function definitions.
+For example, to use stb_image, you should have exactly one C/C++ file that doesn't
+include stb_image.h regularly, but instead does
+
+    #define STB_IMAGE_IMPLEMENTATION
+    #include "stb_image.h"
+
+The right macro to define is pointed out right at the top of each of these libraries.
+
 #### What's the license?
 
 These libraries are in the public domain. You can do anything you

docs/why_public_domain.md

@@ -72,11 +72,12 @@ causes worries for lawyers, even if their programmers
 aren't modifying it.
 
 Any license which requires crediting in documentation
-adds friction which can add up. Valve used to have
-a page with a list of all of these on their web site,
-and it was insane, and obviously nobody ever looked
-at it so why would you care whether your credit appeared
-there?
+adds friction which can add up. Valve has a huge list
+(http://nothings.org/remote/ThirdPartyLegalNotices_steam_2019.html)
+of all of these included in each game they ship,
+and it's insane, and obviously nobody ever looks
+at it so why would you care whether your credit
+appeared there?
 
 Permissive licenses like zlib and BSD license are
 perfectly reasonable, but they are very wordy and

stb_dxt.h

@@ -1,4 +1,4 @@
-// stb_dxt.h - v1.10 - DXT1/DXT5 compressor - public domain
+// stb_dxt.h - v1.11 - DXT1/DXT5 compressor - public domain
 // original by fabian "ryg" giesen - ported to C by stb
 // use '#define STB_DXT_IMPLEMENTATION' before including to create the implementation
 //
@@ -10,6 +10,7 @@
 //     You can turn on dithering and "high quality" using mode.
 //
 // version history:
+//   v1.11  - (ryg) avoid racy global init, better single-color tables, remove dither
 //   v1.10  - (i.c) various small quality improvements
 //   v1.09  - (stb) update documentation re: surprising alpha channel requirement
 //   v1.08  - (stb) fix bug in dxt-with-alpha block
@@ -29,6 +30,7 @@
 //   Kevin Schmidt (#defines for "freestanding" compilation)
 //   github:ppiastucki (BC4 support)
 //   Ignacio Castano - improve DXT endpoint quantization
+//   Alan Hickman - static table initialization
 //
 // LICENSE
 //
@@ -49,7 +51,7 @@ extern "C" {
 
 // compression mode (bitflags)
 #define STB_DXT_NORMAL    0
-#define STB_DXT_DITHER    1   // use dithering. dubious win. never use for normal maps and the like!
+#define STB_DXT_DITHER    1   // use dithering. was always dubious, now deprecated. does nothing!
 #define STB_DXT_HIGHQUAL  2   // high quality mode, does two refinement steps instead of 1. ~30-40% slower.
 
 STBDDEF void stb_compress_dxt_block(unsigned char *dest, const unsigned char *src_rgba_four_bytes_per_pixel, int alpha, int mode);
@@ -81,29 +83,82 @@ STBDDEF void stb_compress_bc5_block(unsigned char *dest, const unsigned char *sr
 
 #include <stdlib.h>
 
-#if !defined(STBD_ABS) || !defined(STBI_FABS)
+#if !defined(STBD_FABS)
 #include <math.h>
 #endif
 
-#ifndef STBD_ABS
-#define STBD_ABS(i)           abs(i)
-#endif
-
 #ifndef STBD_FABS
 #define STBD_FABS(x)          fabs(x)
 #endif
 
-#ifndef STBD_MEMSET
-#include <string.h>
-#define STBD_MEMSET           memset
-#endif
-
-static unsigned char stb__Expand5[32];
-static unsigned char stb__Expand6[64];
-static unsigned char stb__OMatch5[256][2];
-static unsigned char stb__OMatch6[256][2];
-static unsigned char stb__QuantRBTab[256+16];
-static unsigned char stb__QuantGTab[256+16];
+static const unsigned char stb__OMatch5[256][2] = {
+   {  0,  0 }, {  0,  0 }, {  0,  0 }, {  0,  0 }, {  0,  0 }, {  1,  1 }, {  1,  1 }, {  1,  1 },
+   {  1,  1 }, {  1,  1 }, {  1,  1 }, {  1,  1 }, {  1,  1 }, {  2,  2 }, {  2,  2 }, {  2,  2 },
+   {  2,  2 }, {  2,  2 }, {  2,  2 }, {  2,  2 }, {  2,  2 }, {  3,  3 }, {  3,  3 }, {  3,  3 },
+   {  3,  3 }, {  3,  3 }, {  3,  3 }, {  3,  3 }, {  3,  3 }, {  4,  4 }, {  4,  4 }, {  4,  4 },
+   {  4,  4 }, {  4,  4 }, {  4,  4 }, {  4,  4 }, {  4,  4 }, {  4,  4 }, {  5,  5 }, {  5,  5 },
+   {  5,  5 }, {  5,  5 }, {  5,  5 }, {  5,  5 }, {  5,  5 }, {  5,  5 }, {  6,  6 }, {  6,  6 },
+   {  6,  6 }, {  6,  6 }, {  6,  6 }, {  6,  6 }, {  6,  6 }, {  6,  6 }, {  7,  7 }, {  7,  7 },
+   {  7,  7 }, {  7,  7 }, {  7,  7 }, {  7,  7 }, {  7,  7 }, {  7,  7 }, {  8,  8 }, {  8,  8 },
+   {  8,  8 }, {  8,  8 }, {  8,  8 }, {  8,  8 }, {  8,  8 }, {  8,  8 }, {  8,  8 }, {  9,  9 },
+   {  9,  9 }, {  9,  9 }, {  9,  9 }, {  9,  9 }, {  9,  9 }, {  9,  9 }, {  9,  9 }, { 10, 10 },
+   { 10, 10 }, { 10, 10 }, { 10, 10 }, { 10, 10 }, { 10, 10 }, { 10, 10 }, { 10, 10 }, { 11, 11 },
+   { 11, 11 }, { 11, 11 }, { 11, 11 }, { 11, 11 }, { 11, 11 }, { 11, 11 }, { 11, 11 }, { 12, 12 },
+   { 12, 12 }, { 12, 12 }, { 12, 12 }, { 12, 12 }, { 12, 12 }, { 12, 12 }, { 12, 12 }, { 12, 12 },
+   { 13, 13 }, { 13, 13 }, { 13, 13 }, { 13, 13 }, { 13, 13 }, { 13, 13 }, { 13, 13 }, { 13, 13 },
+   { 14, 14 }, { 14, 14 }, { 14, 14 }, { 14, 14 }, { 14, 14 }, { 14, 14 }, { 14, 14 }, { 14, 14 },
+   { 15, 15 }, { 15, 15 }, { 15, 15 }, { 15, 15 }, { 15, 15 }, { 15, 15 }, { 15, 15 }, { 15, 15 },
+   { 16, 16 }, { 16, 16 }, { 16, 16 }, { 16, 16 }, { 16, 16 }, { 16, 16 }, { 16, 16 }, { 16, 16 },
+   { 16, 16 }, { 17, 17 }, { 17, 17 }, { 17, 17 }, { 17, 17 }, { 17, 17 }, { 17, 17 }, { 17, 17 },
+   { 17, 17 }, { 18, 18 }, { 18, 18 }, { 18, 18 }, { 18, 18 }, { 18, 18 }, { 18, 18 }, { 18, 18 },
+   { 18, 18 }, { 19, 19 }, { 19, 19 }, { 19, 19 }, { 19, 19 }, { 19, 19 }, { 19, 19 }, { 19, 19 },
+   { 19, 19 }, { 20, 20 }, { 20, 20 }, { 20, 20 }, { 20, 20 }, { 20, 20 }, { 20, 20 }, { 20, 20 },
+   { 20, 20 }, { 20, 20 }, { 21, 21 }, { 21, 21 }, { 21, 21 }, { 21, 21 }, { 21, 21 }, { 21, 21 },
+   { 21, 21 }, { 21, 21 }, { 22, 22 }, { 22, 22 }, { 22, 22 }, { 22, 22 }, { 22, 22 }, { 22, 22 },
+   { 22, 22 }, { 22, 22 }, { 23, 23 }, { 23, 23 }, { 23, 23 }, { 23, 23 }, { 23, 23 }, { 23, 23 },
+   { 23, 23 }, { 23, 23 }, { 24, 24 }, { 24, 24 }, { 24, 24 }, { 24, 24 }, { 24, 24 }, { 24, 24 },
+   { 24, 24 }, { 24, 24 }, { 24, 24 }, { 25, 25 }, { 25, 25 }, { 25, 25 }, { 25, 25 }, { 25, 25 },
+   { 25, 25 }, { 25, 25 }, { 25, 25 }, { 26, 26 }, { 26, 26 }, { 26, 26 }, { 26, 26 }, { 26, 26 },
+   { 26, 26 }, { 26, 26 }, { 26, 26 }, { 27, 27 }, { 27, 27 }, { 27, 27 }, { 27, 27 }, { 27, 27 },
+   { 27, 27 }, { 27, 27 }, { 27, 27 }, { 28, 28 }, { 28, 28 }, { 28, 28 }, { 28, 28 }, { 28, 28 },
+   { 28, 28 }, { 28, 28 }, { 28, 28 }, { 28, 28 }, { 29, 29 }, { 29, 29 }, { 29, 29 }, { 29, 29 },
+   { 29, 29 }, { 29, 29 }, { 29, 29 }, { 29, 29 }, { 30, 30 }, { 30, 30 }, { 30, 30 }, { 30, 30 },
+   { 30, 30 }, { 30, 30 }, { 30, 30 }, { 30, 30 }, { 31, 31 }, { 31, 31 }, { 31, 31 }, { 31, 31 },
+};
+static const unsigned char stb__OMatch6[256][2] = {
+   {  0,  0 }, {  0,  0 }, {  0,  0 }, {  1,  1 }, {  1,  1 }, {  1,  1 }, {  1,  1 }, {  2,  2 },
+   {  2,  2 }, {  2,  2 }, {  2,  2 }, {  3,  3 }, {  3,  3 }, {  3,  3 }, {  3,  3 }, {  4,  4 },
+   {  4,  4 }, {  4,  4 }, {  4,  4 }, {  5,  5 }, {  5,  5 }, {  5,  5 }, {  5,  5 }, {  6,  6 },
+   {  6,  6 }, {  6,  6 }, {  6,  6 }, {  7,  7 }, {  7,  7 }, {  7,  7 }, {  7,  7 }, {  8,  8 },
+   {  8,  8 }, {  8,  8 }, {  8,  8 }, {  9,  9 }, {  9,  9 }, {  9,  9 }, {  9,  9 }, { 10, 10 },
+   { 10, 10 }, { 10, 10 }, { 10, 10 }, { 11, 11 }, { 11, 11 }, { 11, 11 }, { 11, 11 }, { 12, 12 },
+   { 12, 12 }, { 12, 12 }, { 12, 12 }, { 13, 13 }, { 13, 13 }, { 13, 13 }, { 13, 13 }, { 14, 14 },
+   { 14, 14 }, { 14, 14 }, { 14, 14 }, { 15, 15 }, { 15, 15 }, { 15, 15 }, { 15, 15 }, { 16, 16 },
+   { 16, 16 }, { 16, 16 }, { 16, 16 }, { 16, 16 }, { 17, 17 }, { 17, 17 }, { 17, 17 }, { 17, 17 },
+   { 18, 18 }, { 18, 18 }, { 18, 18 }, { 18, 18 }, { 19, 19 }, { 19, 19 }, { 19, 19 }, { 19, 19 },
+   { 20, 20 }, { 20, 20 }, { 20, 20 }, { 20, 20 }, { 21, 21 }, { 21, 21 }, { 21, 21 }, { 21, 21 },
+   { 22, 22 }, { 22, 22 }, { 22, 22 }, { 22, 22 }, { 23, 23 }, { 23, 23 }, { 23, 23 }, { 23, 23 },
+   { 24, 24 }, { 24, 24 }, { 24, 24 }, { 24, 24 }, { 25, 25 }, { 25, 25 }, { 25, 25 }, { 25, 25 },
+   { 26, 26 }, { 26, 26 }, { 26, 26 }, { 26, 26 }, { 27, 27 }, { 27, 27 }, { 27, 27 }, { 27, 27 },
+   { 28, 28 }, { 28, 28 }, { 28, 28 }, { 28, 28 }, { 29, 29 }, { 29, 29 }, { 29, 29 }, { 29, 29 },
+   { 30, 30 }, { 30, 30 }, { 30, 30 }, { 30, 30 }, { 31, 31 }, { 31, 31 }, { 31, 31 }, { 31, 31 },
+   { 32, 32 }, { 32, 32 }, { 32, 32 }, { 32, 32 }, { 32, 32 }, { 33, 33 }, { 33, 33 }, { 33, 33 },
+   { 33, 33 }, { 34, 34 }, { 34, 34 }, { 34, 34 }, { 34, 34 }, { 35, 35 }, { 35, 35 }, { 35, 35 },
+   { 35, 35 }, { 36, 36 }, { 36, 36 }, { 36, 36 }, { 36, 36 }, { 37, 37 }, { 37, 37 }, { 37, 37 },
+   { 37, 37 }, { 38, 38 }, { 38, 38 }, { 38, 38 }, { 38, 38 }, { 39, 39 }, { 39, 39 }, { 39, 39 },
+   { 39, 39 }, { 40, 40 }, { 40, 40 }, { 40, 40 }, { 40, 40 }, { 41, 41 }, { 41, 41 }, { 41, 41 },
+   { 41, 41 }, { 42, 42 }, { 42, 42 }, { 42, 42 }, { 42, 42 }, { 43, 43 }, { 43, 43 }, { 43, 43 },
+   { 43, 43 }, { 44, 44 }, { 44, 44 }, { 44, 44 }, { 44, 44 }, { 45, 45 }, { 45, 45 }, { 45, 45 },
+   { 45, 45 }, { 46, 46 }, { 46, 46 }, { 46, 46 }, { 46, 46 }, { 47, 47 }, { 47, 47 }, { 47, 47 },
+   { 47, 47 }, { 48, 48 }, { 48, 48 }, { 48, 48 }, { 48, 48 }, { 48, 48 }, { 49, 49 }, { 49, 49 },
+   { 49, 49 }, { 49, 49 }, { 50, 50 }, { 50, 50 }, { 50, 50 }, { 50, 50 }, { 51, 51 }, { 51, 51 },
+   { 51, 51 }, { 51, 51 }, { 52, 52 }, { 52, 52 }, { 52, 52 }, { 52, 52 }, { 53, 53 }, { 53, 53 },
+   { 53, 53 }, { 53, 53 }, { 54, 54 }, { 54, 54 }, { 54, 54 }, { 54, 54 }, { 55, 55 }, { 55, 55 },
+   { 55, 55 }, { 55, 55 }, { 56, 56 }, { 56, 56 }, { 56, 56 }, { 56, 56 }, { 57, 57 }, { 57, 57 },
+   { 57, 57 }, { 57, 57 }, { 58, 58 }, { 58, 58 }, { 58, 58 }, { 58, 58 }, { 59, 59 }, { 59, 59 },
+   { 59, 59 }, { 59, 59 }, { 60, 60 }, { 60, 60 }, { 60, 60 }, { 60, 60 }, { 61, 61 }, { 61, 61 },
+   { 61, 61 }, { 61, 61 }, { 62, 62 }, { 62, 62 }, { 62, 62 }, { 62, 62 }, { 63, 63 }, { 63, 63 },
+};
 
 static int stb__Mul8Bit(int a, int b)
 {
@@ -117,9 +172,10 @@ static void stb__From16Bit(unsigned char *out, unsigned short v)
    int gv = (v & 0x07e0) >>  5;
    int bv = (v & 0x001f) >>  0;
 
-   out[0] = stb__Expand5[rv];
-   out[1] = stb__Expand6[gv];
-   out[2] = stb__Expand5[bv];
+   // expand to 8 bits via bit replication
+   out[0] = (rv * 33) >> 2;
+   out[1] = (gv * 65) >> 4;
+   out[2] = (bv * 33) >> 2;
    out[3] = 0;
 }
 
@@ -151,35 +207,6 @@ static void stb__Lerp13RGB(unsigned char *out, unsigned char *p1, unsigned char
 
 /****************************************************************************/
 
-// compute table to reproduce constant colors as accurately as possible
-static void stb__PrepareOptTable(unsigned char *Table,const unsigned char *expand,int size)
-{
-   int i,mn,mx;
-   for (i=0;i<256;i++) {
-      int bestErr = 256;
-      for (mn=0;mn<size;mn++) {
-         for (mx=0;mx<size;mx++) {
-            int mine = expand[mn];
-            int maxe = expand[mx];
-            int err = STBD_ABS(stb__Lerp13(maxe, mine) - i);
-
-            // DX10 spec says that interpolation must be within 3% of "correct" result,
-            // add this as error term. (normally we'd expect a random distribution of
-            // +-1.5% error, but nowhere in the spec does it say that the error has to be
-            // unbiased - better safe than sorry).
-            err += STBD_ABS(maxe - mine) * 3 / 100;
-
-            if(err < bestErr)
-            {
-               Table[i*2+0] = (unsigned char)mx;
-               Table[i*2+1] = (unsigned char)mn;
-               bestErr = err;
-            }
-         }
-      }
-   }
-}
-
 static void stb__EvalColors(unsigned char *color,unsigned short c0,unsigned short c1)
 {
    stb__From16Bit(color+ 0, c0);
@@ -188,36 +215,8 @@ static void stb__EvalColors(unsigned char *color,unsigned short c0,unsigned shor
    stb__Lerp13RGB(color+12, color+4, color+0);
 }
 
-// Block dithering function. Simply dithers a block to 565 RGB.
-// (Floyd-Steinberg)
-static void stb__DitherBlock(unsigned char *dest, unsigned char *block)
-{
-  int err[8],*ep1 = err,*ep2 = err+4, *et;
-  int ch,y;
-
-  // process channels separately
-  for (ch=0; ch<3; ++ch) {
-      unsigned char *bp = block+ch, *dp = dest+ch;
-      unsigned char *quant = (ch == 1) ? stb__QuantGTab+8 : stb__QuantRBTab+8;
-      STBD_MEMSET(err, 0, sizeof(err));
-      for(y=0; y<4; ++y) {
-         dp[ 0] = quant[bp[ 0] + ((3*ep2[1] + 5*ep2[0]) >> 4)];
-         ep1[0] = bp[ 0] - dp[ 0];
-         dp[ 4] = quant[bp[ 4] + ((7*ep1[0] + 3*ep2[2] + 5*ep2[1] + ep2[0]) >> 4)];
-         ep1[1] = bp[ 4] - dp[ 4];
-         dp[ 8] = quant[bp[ 8] + ((7*ep1[1] + 3*ep2[3] + 5*ep2[2] + ep2[1]) >> 4)];
-         ep1[2] = bp[ 8] - dp[ 8];
-         dp[12] = quant[bp[12] + ((7*ep1[2] + 5*ep2[3] + ep2[2]) >> 4)];
-         ep1[3] = bp[12] - dp[12];
-         bp += 16;
-         dp += 16;
-         et = ep1, ep1 = ep2, ep2 = et; // swap
-      }
-   }
-}
-
 // The color matching function
-static unsigned int stb__MatchColorsBlock(unsigned char *block, unsigned char *color,int dither)
+static unsigned int stb__MatchColorsBlock(unsigned char *block, unsigned char *color)
 {
    unsigned int mask = 0;
    int dirr = color[0*4+0] - color[1*4+0];
@@ -246,68 +245,14 @@ static unsigned int stb__MatchColorsBlock(unsigned char *block, unsigned char *c
    halfPoint = (stops[3] + stops[2]);
    c3Point   = (stops[2] + stops[0]);
 
-   if(!dither) {
-      // the version without dithering is straightforward
-      for (i=15;i>=0;i--) {
-         int dot = dots[i]*2;
-         mask <<= 2;
+   for (i=15;i>=0;i--) {
+      int dot = dots[i]*2;
+      mask <<= 2;
 
-         if(dot < halfPoint)
-           mask |= (dot < c0Point) ? 1 : 3;
-         else
-           mask |= (dot < c3Point) ? 2 : 0;
-      }
-  } else {
-      // with floyd-steinberg dithering
-      int err[8],*ep1 = err,*ep2 = err+4;
-      int *dp = dots, y;
-
-      c0Point   <<= 3;
-      halfPoint <<= 3;
-      c3Point   <<= 3;
-      for(i=0;i<8;i++)
-         err[i] = 0;
-
-      for(y=0;y<4;y++)
-      {
-         int dot,lmask,step;
-
-         dot = (dp[0] << 4) + (3*ep2[1] + 5*ep2[0]);
-         if(dot < halfPoint)
-           step = (dot < c0Point) ? 1 : 3;
-         else
-           step = (dot < c3Point) ? 2 : 0;
-         ep1[0] = dp[0] - stops[step];
-         lmask = step;
-
-         dot = (dp[1] << 4) + (7*ep1[0] + 3*ep2[2] + 5*ep2[1] + ep2[0]);
-         if(dot < halfPoint)
-           step = (dot < c0Point) ? 1 : 3;
-         else
-           step = (dot < c3Point) ? 2 : 0;
-         ep1[1] = dp[1] - stops[step];
-         lmask |= step<<2;
-
-         dot = (dp[2] << 4) + (7*ep1[1] + 3*ep2[3] + 5*ep2[2] + ep2[1]);
-         if(dot < halfPoint)
-           step = (dot < c0Point) ? 1 : 3;
-         else
-           step = (dot < c3Point) ? 2 : 0;
-         ep1[2] = dp[2] - stops[step];
-         lmask |= step<<4;
-
-         dot = (dp[3] << 4) + (7*ep1[2] + 5*ep2[3] + ep2[2]);
-         if(dot < halfPoint)
-           step = (dot < c0Point) ? 1 : 3;
-         else
-           step = (dot < c3Point) ? 2 : 0;
-         ep1[3] = dp[3] - stops[step];
-         lmask |= step<<6;
-
-         dp += 4;
-         mask |= lmask << (y*8);
-         { int *et = ep1; ep1 = ep2; ep2 = et; } // swap
-      }
+      if(dot < halfPoint)
+         mask |= (dot < c0Point) ? 1 : 3;
+      else
+         mask |= (dot < c3Point) ? 2 : 0;
    }
 
    return mask;
@@ -316,7 +261,7 @@ static unsigned int stb__MatchColorsBlock(unsigned char *block, unsigned char *c
 // The color optimization function. (Clever code, part 1)
 static void stb__OptimizeColorsBlock(unsigned char *block, unsigned short *pmax16, unsigned short *pmin16)
 {
-  int mind = 0x7fffffff,maxd = -0x7fffffff;
+  int mind,maxd;
   unsigned char *minp, *maxp;
   double magn;
   int v_r,v_g,v_b;
@@ -398,8 +343,10 @@ static void stb__OptimizeColorsBlock(unsigned char *block, unsigned short *pmax1
       v_b = (int) (vfb * magn);
    }
 
+   minp = maxp = block;
+   mind = maxd = block[0]*v_r + block[1]*v_g + block[2]*v_b;
    // Pick colors at extreme points
-   for(i=0;i<16;i++)
+   for(i=1;i<16;i++)
    {
       int dot = block[i*4+0]*v_r + block[i*4+1]*v_g + block[i*4+2]*v_b;
 
@@ -418,12 +365,12 @@ static void stb__OptimizeColorsBlock(unsigned char *block, unsigned short *pmax1
    *pmin16 = stb__As16Bit(minp[0],minp[1],minp[2]);
 }
 
-static const float midpoints5[32] = {
+static const float stb__midpoints5[32] = {
    0.015686f, 0.047059f, 0.078431f, 0.111765f, 0.145098f, 0.176471f, 0.207843f, 0.241176f, 0.274510f, 0.305882f, 0.337255f, 0.370588f, 0.403922f, 0.435294f, 0.466667f, 0.5f,
    0.533333f, 0.564706f, 0.596078f, 0.629412f, 0.662745f, 0.694118f, 0.725490f, 0.758824f, 0.792157f, 0.823529f, 0.854902f, 0.888235f, 0.921569f, 0.952941f, 0.984314f, 1.0f
 };
 
-static const float midpoints6[64] = {
+static const float stb__midpoints6[64] = {
    0.007843f, 0.023529f, 0.039216f, 0.054902f, 0.070588f, 0.086275f, 0.101961f, 0.117647f, 0.133333f, 0.149020f, 0.164706f, 0.180392f, 0.196078f, 0.211765f, 0.227451f, 0.245098f,
    0.262745f, 0.278431f, 0.294118f, 0.309804f, 0.325490f, 0.341176f, 0.356863f, 0.372549f, 0.388235f, 0.403922f, 0.419608f, 0.435294f, 0.450980f, 0.466667f, 0.482353f, 0.500000f,
    0.517647f, 0.533333f, 0.549020f, 0.564706f, 0.580392f, 0.596078f, 0.611765f, 0.627451f, 0.643137f, 0.658824f, 0.674510f, 0.690196f, 0.705882f, 0.721569f, 0.737255f, 0.754902f,
@@ -435,7 +382,7 @@ static unsigned short stb__Quantize5(float x)
    unsigned short q;
    x = x < 0 ? 0 : x > 1 ? 1 : x;  // saturate
    q = (unsigned short)(x * 31);
-   q += (x > midpoints5[q]);
+   q += (x > stb__midpoints5[q]);
    return q;
 }
 
@@ -444,7 +391,7 @@ static unsigned short stb__Quantize6(float x)
    unsigned short q;
    x = x < 0 ? 0 : x > 1 ? 1 : x;  // saturate
    q = (unsigned short)(x * 63);
-   q += (x > midpoints6[q]);
+   q += (x > stb__midpoints6[q]);
    return q;
 }
 
@@ -532,12 +479,10 @@ static void stb__CompressColorBlock(unsigned char *dest, unsigned char *block, i
 {
    unsigned int mask;
    int i;
-   int dither;
    int refinecount;
    unsigned short max16, min16;
-   unsigned char dblock[16*4],color[4*4];
+   unsigned char color[4*4];
 
-   dither = mode & STB_DXT_DITHER;
    refinecount = (mode & STB_DXT_HIGHQUAL) ? 2 : 1;
 
    // check if block is constant
@@ -551,15 +496,11 @@ static void stb__CompressColorBlock(unsigned char *dest, unsigned char *block, i
       max16 = (stb__OMatch5[r][0]<<11) | (stb__OMatch6[g][0]<<5) | stb__OMatch5[b][0];
       min16 = (stb__OMatch5[r][1]<<11) | (stb__OMatch6[g][1]<<5) | stb__OMatch5[b][1];
    } else {
-      // first step: compute dithered version for PCA if desired
-      if(dither)
-         stb__DitherBlock(dblock,block);
-
-      // second step: pca+map along principal axis
-      stb__OptimizeColorsBlock(dither ? dblock : block,&max16,&min16);
+      // first step: PCA+map along principal axis
+      stb__OptimizeColorsBlock(block,&max16,&min16);
       if (max16 != min16) {
          stb__EvalColors(color,max16,min16);
-         mask = stb__MatchColorsBlock(block,color,dither);
+         mask = stb__MatchColorsBlock(block,color);
       } else
          mask = 0;
 
@@ -567,10 +508,10 @@ static void stb__CompressColorBlock(unsigned char *dest, unsigned char *block, i
       for (i=0;i<refinecount;i++) {
          unsigned int lastmask = mask;
 
-         if (stb__RefineBlock(dither ? dblock : block,&max16,&min16,mask)) {
+         if (stb__RefineBlock(block,&max16,&min16,mask)) {
             if (max16 != min16) {
                stb__EvalColors(color,max16,min16);
-               mask = stb__MatchColorsBlock(block,color,dither);
+               mask = stb__MatchColorsBlock(block,color);
             } else {
                mask = 0;
                break;
@@ -654,35 +595,9 @@ static void stb__CompressAlphaBlock(unsigned char *dest,unsigned char *src, int
    }
 }
 
-static void stb__InitDXT()
-{
-   int i;
-   for(i=0;i<32;i++)
-      stb__Expand5[i] = (unsigned char)((i<<3)|(i>>2));
-
-   for(i=0;i<64;i++)
-      stb__Expand6[i] = (unsigned char)((i<<2)|(i>>4));
-
-   for(i=0;i<256+16;i++)
-   {
-      int v = i-8 < 0 ? 0 : i-8 > 255 ? 255 : i-8;
-      stb__QuantRBTab[i] = stb__Expand5[stb__Mul8Bit(v,31)];
-      stb__QuantGTab[i] = stb__Expand6[stb__Mul8Bit(v,63)];
-   }
-
-   stb__PrepareOptTable(&stb__OMatch5[0][0],stb__Expand5,32);
-   stb__PrepareOptTable(&stb__OMatch6[0][0],stb__Expand6,64);
-}
-
 void stb_compress_dxt_block(unsigned char *dest, const unsigned char *src, int alpha, int mode)
 {
    unsigned char data[16][4];
-   static int init=1;
-   if (init) {
-      stb__InitDXT();
-      init=0;
-   }
-
    if (alpha) {
       int i;
       stb__CompressAlphaBlock(dest,(unsigned char*) src+3, 4);
@@ -710,6 +625,56 @@ void stb_compress_bc5_block(unsigned char *dest, const unsigned char *src)
 }
 #endif // STB_DXT_IMPLEMENTATION
 
+// Compile with STB_DXT_IMPLEMENTATION and STB_DXT_GENERATE_TABLES
+// defined to generate the tables above.
+#ifdef STB_DXT_GENERATE_TABLES
+#include <stdio.h>
+
+int main()
+{
+   int i, j;
+   const char *omatch_names[] = { "stb__OMatch5", "stb__OMatch6" };
+   int dequant_mults[2] = { 33*4, 65 }; // .4 fixed-point dequant multipliers
+
+   // optimal endpoint tables
+   for (i = 0; i < 2; ++i) {
+      int dequant = dequant_mults[i];
+      int size = i ? 64 : 32;
+      printf("static const unsigned char %s[256][2] = {\n", omatch_names[i]);
+      for (int j = 0; j < 256; ++j) {
+         int mn, mx;
+         int best_mn = 0, best_mx = 0;
+         int best_err = 256 * 100;
+         for (mn=0;mn<size;mn++) {
+            for (mx=0;mx<size;mx++) {
+               int mine = (mn * dequant) >> 4;
+               int maxe = (mx * dequant) >> 4;
+               int err = abs(stb__Lerp13(maxe, mine) - j);
+
+               // DX10 spec says that interpolation must be within 3% of "correct" result,
+               // add this as error term. Normally we'd expect a random distribution of
+               // +-1.5% error, but nowhere in the spec does it say that the error has to be
+               // unbiased - better safe than sorry.
+               err += abs(maxe - mine) * 3;
+
+               if(err < best_err) {
+                  best_mn = mn;
+                  best_mx = mx;
+                  best_err = err;
+               }
+            }
+         }
+         if ((j % 8) == 0) printf("  "); // 2 spaces, third is done below
+         printf(" { %2d, %2d },", best_mx, best_mn);
+         if ((j % 8) == 7) printf("\n");
+      }
+      printf("};\n");
+   }
+
+   return 0;
+}
+#endif
+
 /*
 ------------------------------------------------------------------------------
 This software is available under 2 licenses -- choose whichever you prefer.

stb_image.h

@@ -1,4 +1,4 @@
-/* stb_image - v2.26 - public domain image loader - http://nothings.org/stb
+/* stb_image - v2.27 - public domain image loader - http://nothings.org/stb
                                   no warranty implied; use at your own risk
 
    Do this:
@@ -48,6 +48,7 @@ LICENSE
 
 RECENT REVISION HISTORY:
 
+      2.27  (          ) document stbi_info better, 16-bit PNM support, bug fixes
       2.26  (2020-07-13) many minor fixes
       2.25  (2020-02-02) fix warnings
       2.24  (2020-02-02) fix warnings; thread-local failure_reason and flip_vertically
@@ -89,7 +90,7 @@ RECENT REVISION HISTORY:
                                            Jeremy Sawicki (handle all ImageNet JPGs)
  Optimizations & bugfixes                  Mikhail Morozov (1-bit BMP)
     Fabian "ryg" Giesen                    Anael Seghezzi (is-16-bit query)
-    Arseny Kapoulkine
+    Arseny Kapoulkine                      Simon Breuss (16-bit PNM)
     John-Mark Allen
     Carmelo J Fdez-Aguera
 
@@ -102,7 +103,7 @@ RECENT REVISION HISTORY:
     Thomas Ruf              Ronny Chevalier                         github:rlyeh
     Janez Zemva             John Bartholomew   Michal Cichon        github:romigrou
     Jonathan Blow           Ken Hamada         Tero Hanninen        github:svdijk
-                            Laurent Gomila     Cort Stratton        github:snagar
+    Eugene Golushkov        Laurent Gomila     Cort Stratton        github:snagar
     Aruelien Pocheville     Sergio Gonzalez    Thibault Reuille     github:Zelex
     Cass Everitt            Ryamond Barbiero                        github:grim210
     Paul Du Bois            Engin Manap        Aldo Culquicondor    github:sammyhw
@@ -115,6 +116,8 @@ RECENT REVISION HISTORY:
     Ryan C. Gordon          [reserved]                              [reserved]
                      DO NOT ADD YOUR NAME HERE
 
+                     Jacko Dirks
+
   To add your name to the credits, pick a random blank space in the middle and fill it.
   80% of merge conflicts on stb PRs are due to people adding their name at the end
   of the credits.
@@ -176,6 +179,32 @@ RECENT REVISION HISTORY:
 //
 // Paletted PNG, BMP, GIF, and PIC images are automatically depalettized.
 //
+// To query the width, height and component count of an image without having to
+// decode the full file, you can use the stbi_info family of functions:
+//
+//   int x,y,n,ok;
+//   ok = stbi_info(filename, &x, &y, &n);
+//   // returns ok=1 and sets x, y, n if image is a supported format,
+//   // 0 otherwise.
+//
+// Note that stb_image pervasively uses ints in its public API for sizes,
+// including sizes of memory buffers. This is now part of the API and thus
+// hard to change without causing breakage. As a result, the various image
+// loaders all have certain limits on image size; these differ somewhat
+// by format but generally boil down to either just under 2GB or just under
+// 1GB. When the decoded image would be larger than this, stb_image decoding
+// will fail.
+//
+// Additionally, stb_image will reject image files that have any of their
+// dimensions set to a larger value than the configurable STBI_MAX_DIMENSIONS,
+// which defaults to 2**24 = 16777216 pixels. Due to the above memory limit,
+// the only way to have an image with such dimensions load correctly
+// is for it to have a rather extreme aspect ratio. Either way, the
+// assumption here is that such larger images are likely to be malformed
+// or malicious. If you do need to load an image with individual dimensions
+// larger than that, and it still fits in the overall size limit, you can
+// #define STBI_MAX_DIMENSIONS on your own to be something larger.
+//
 // ===========================================================================
 //
 // UNICODE:
@@ -634,7 +663,7 @@ typedef unsigned char validate_uint32[sizeof(stbi__uint32)==4 ? 1 : -1];
 #ifdef STBI_HAS_LROTL
    #define stbi_lrot(x,y)  _lrotl(x,y)
 #else
-   #define stbi_lrot(x,y)  (((x) << (y)) | ((x) >> (32 - (y))))
+   #define stbi_lrot(x,y)  (((x) << (y)) | ((x) >> (-(y) & 31)))
 #endif
 
 #if defined(STBI_MALLOC) && defined(STBI_FREE) && (defined(STBI_REALLOC) || defined(STBI_REALLOC_SIZED))
@@ -748,9 +777,12 @@ static int stbi__sse2_available(void)
 
 #ifdef STBI_NEON
 #include <arm_neon.h>
-// assume GCC or Clang on ARM targets
+#ifdef _MSC_VER
+#define STBI_SIMD_ALIGN(type, name) __declspec(align(16)) type name
+#else
 #define STBI_SIMD_ALIGN(type, name) type name __attribute__((aligned(16)))
 #endif
+#endif
 
 #ifndef STBI_SIMD_ALIGN
 #define STBI_SIMD_ALIGN(type, name) type name
@@ -924,6 +956,7 @@ static int      stbi__gif_info(stbi__context *s, int *x, int *y, int *comp);
 static int      stbi__pnm_test(stbi__context *s);
 static void    *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req_comp, stbi__result_info *ri);
 static int      stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp);
+static int      stbi__pnm_is16(stbi__context *s);
 #endif
 
 static
@@ -1087,9 +1120,8 @@ static void *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int re
    ri->channel_order = STBI_ORDER_RGB; // all current input & output are this, but this is here so we can add BGR order
    ri->num_channels = 0;
 
-   #ifndef STBI_NO_JPEG
-   if (stbi__jpeg_test(s)) return stbi__jpeg_load(s,x,y,comp,req_comp, ri);
-   #endif
+   // test the formats with a very explicit header first (at least a FOURCC
+   // or distinctive magic number first)
    #ifndef STBI_NO_PNG
    if (stbi__png_test(s))  return stbi__png_load(s,x,y,comp,req_comp, ri);
    #endif
@@ -1107,6 +1139,13 @@ static void *stbi__load_main(stbi__context *s, int *x, int *y, int *comp, int re
    #ifndef STBI_NO_PIC
    if (stbi__pic_test(s))  return stbi__pic_load(s,x,y,comp,req_comp, ri);
    #endif
+
+   // then the formats that can end up attempting to load with just 1 or 2
+   // bytes matching expectations; these are prone to false positives, so
+   // try them later
+   #ifndef STBI_NO_JPEG
+   if (stbi__jpeg_test(s)) return stbi__jpeg_load(s,x,y,comp,req_comp, ri);
+   #endif
    #ifndef STBI_NO_PNM
    if (stbi__pnm_test(s))  return stbi__pnm_load(s,x,y,comp,req_comp, ri);
    #endif
@@ -1262,12 +1301,12 @@ static void stbi__float_postprocess(float *result, int *x, int *y, int *comp, in
 
 #ifndef STBI_NO_STDIO
 
-#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+#if defined(_WIN32) && defined(STBI_WINDOWS_UTF8)
 STBI_EXTERN __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned int cp, unsigned long flags, const char *str, int cbmb, wchar_t *widestr, int cchwide);
 STBI_EXTERN __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int cp, unsigned long flags, const wchar_t *widestr, int cchwide, char *str, int cbmb, const char *defchar, int *used_default);
 #endif
 
-#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+#if defined(_WIN32) && defined(STBI_WINDOWS_UTF8)
 STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wchar_t* input)
 {
 	return WideCharToMultiByte(65001 /* UTF8 */, 0, input, -1, buffer, (int) bufferlen, NULL, NULL);
@@ -1277,16 +1316,16 @@ STBIDEF int stbi_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const wch
 static FILE *stbi__fopen(char const *filename, char const *mode)
 {
    FILE *f;
-#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+#if defined(_WIN32) && defined(STBI_WINDOWS_UTF8)
    wchar_t wMode[64];
    wchar_t wFilename[1024];
-	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)))
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)/sizeof(*wFilename)))
       return 0;
 
-	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)))
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)/sizeof(*wMode)))
       return 0;
 
-#if _MSC_VER >= 1400
+#if defined(_MSC_VER) && _MSC_VER >= 1400
 	if (0 != _wfopen_s(&f, wFilename, wMode))
 		f = 0;
 #else
@@ -1662,7 +1701,8 @@ static int stbi__get16le(stbi__context *s)
 static stbi__uint32 stbi__get32le(stbi__context *s)
 {
    stbi__uint32 z = stbi__get16le(s);
-   return z + (stbi__get16le(s) << 16);
+   z += (stbi__uint32)stbi__get16le(s) << 16;
+   return z;
 }
 #endif
 
@@ -2090,13 +2130,12 @@ stbi_inline static int stbi__extend_receive(stbi__jpeg *j, int n)
    int sgn;
    if (j->code_bits < n) stbi__grow_buffer_unsafe(j);
 
-   sgn = (stbi__int32)j->code_buffer >> 31; // sign bit is always in MSB
+   sgn = j->code_buffer >> 31; // sign bit always in MSB; 0 if MSB clear (positive), 1 if MSB set (negative)
    k = stbi_lrot(j->code_buffer, n);
-   if (n < 0 || n >= (int) (sizeof(stbi__bmask)/sizeof(*stbi__bmask))) return 0;
    j->code_buffer = k & ~stbi__bmask[n];
    k &= stbi__bmask[n];
    j->code_bits -= n;
-   return k + (stbi__jbias[n] & ~sgn);
+   return k + (stbi__jbias[n] & (sgn - 1));
 }
 
 // get some unsigned bits
@@ -2146,7 +2185,7 @@ static int stbi__jpeg_decode_block(stbi__jpeg *j, short data[64], stbi__huffman
 
    if (j->code_bits < 16) stbi__grow_buffer_unsafe(j);
    t = stbi__jpeg_huff_decode(j, hdc);
-   if (t < 0) return stbi__err("bad huffman code","Corrupt JPEG");
+   if (t < 0 || t > 15) return stbi__err("bad huffman code","Corrupt JPEG");
 
    // 0 all the ac values now so we can do it 32-bits at a time
    memset(data,0,64*sizeof(data[0]));
@@ -2203,12 +2242,12 @@ static int stbi__jpeg_decode_block_prog_dc(stbi__jpeg *j, short data[64], stbi__
       // first scan for DC coefficient, must be first
       memset(data,0,64*sizeof(data[0])); // 0 all the ac values now
       t = stbi__jpeg_huff_decode(j, hdc);
-      if (t == -1) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
+      if (t < 0 || t > 15) return stbi__err("can't merge dc and ac", "Corrupt JPEG");
       diff = t ? stbi__extend_receive(j, t) : 0;
 
       dc = j->img_comp[b].dc_pred + diff;
       j->img_comp[b].dc_pred = dc;
-      data[0] = (short) (dc << j->succ_low);
+      data[0] = (short) (dc * (1 << j->succ_low));
    } else {
       // refinement scan for DC coefficient
       if (stbi__jpeg_get_bit(j))
@@ -2245,7 +2284,7 @@ static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__
             j->code_buffer <<= s;
             j->code_bits -= s;
             zig = stbi__jpeg_dezigzag[k++];
-            data[zig] = (short) ((r >> 8) << shift);
+            data[zig] = (short) ((r >> 8) * (1 << shift));
          } else {
             int rs = stbi__jpeg_huff_decode(j, hac);
             if (rs < 0) return stbi__err("bad huffman code","Corrupt JPEG");
@@ -2263,7 +2302,7 @@ static int stbi__jpeg_decode_block_prog_ac(stbi__jpeg *j, short data[64], stbi__
             } else {
                k += r;
                zig = stbi__jpeg_dezigzag[k++];
-               data[zig] = (short) (stbi__extend_receive(j,s) << shift);
+               data[zig] = (short) (stbi__extend_receive(j,s) * (1 << shift));
             }
          }
       } while (k <= j->spec_end);
@@ -3924,6 +3963,7 @@ static void *stbi__jpeg_load(stbi__context *s, int *x, int *y, int *comp, int re
 {
    unsigned char* result;
    stbi__jpeg* j = (stbi__jpeg*) stbi__malloc(sizeof(stbi__jpeg));
+   if (!j) return stbi__errpuc("outofmem", "Out of memory");
    STBI_NOTUSED(ri);
    j->s = s;
    stbi__setup_jpeg(j);
@@ -3936,6 +3976,7 @@ static int stbi__jpeg_test(stbi__context *s)
 {
    int r;
    stbi__jpeg* j = (stbi__jpeg*)stbi__malloc(sizeof(stbi__jpeg));
+   if (!j) return stbi__err("outofmem", "Out of memory");
    j->s = s;
    stbi__setup_jpeg(j);
    r = stbi__decode_jpeg_header(j, STBI__SCAN_type);
@@ -3960,6 +4001,7 @@ static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp)
 {
    int result;
    stbi__jpeg* j = (stbi__jpeg*) (stbi__malloc(sizeof(stbi__jpeg)));
+   if (!j) return stbi__err("outofmem", "Out of memory");
    j->s = s;
    result = stbi__jpeg_info_raw(j, x, y, comp);
    STBI_FREE(j);
@@ -3979,6 +4021,7 @@ static int stbi__jpeg_info(stbi__context *s, int *x, int *y, int *comp)
 // fast-way is faster to check than jpeg huffman, but slow way is slower
 #define STBI__ZFAST_BITS  9 // accelerate all cases in default tables
 #define STBI__ZFAST_MASK  ((1 << STBI__ZFAST_BITS) - 1)
+#define STBI__ZNSYMS 288 // number of symbols in literal/length alphabet
 
 // zlib-style huffman encoding
 // (jpegs packs from left, zlib from right, so can't share code)
@@ -3988,8 +4031,8 @@ typedef struct
    stbi__uint16 firstcode[16];
    int maxcode[17];
    stbi__uint16 firstsymbol[16];
-   stbi_uc  size[288];
-   stbi__uint16 value[288];
+   stbi_uc  size[STBI__ZNSYMS];
+   stbi__uint16 value[STBI__ZNSYMS];
 } stbi__zhuffman;
 
 stbi_inline static int stbi__bitreverse16(int n)
@@ -4120,7 +4163,7 @@ static int stbi__zhuffman_decode_slowpath(stbi__zbuf *a, stbi__zhuffman *z)
    if (s >= 16) return -1; // invalid code!
    // code size is s, so:
    b = (k >> (16-s)) - z->firstcode[s] + z->firstsymbol[s];
-   if (b >= sizeof (z->size)) return -1; // some data was corrupt somewhere!
+   if (b >= STBI__ZNSYMS) return -1; // some data was corrupt somewhere!
    if (z->size[b] != s) return -1;  // was originally an assert, but report failure instead.
    a->code_buffer >>= s;
    a->num_bits -= s;
@@ -4317,7 +4360,7 @@ static int stbi__parse_zlib_header(stbi__zbuf *a)
    return 1;
 }
 
-static const stbi_uc stbi__zdefault_length[288] =
+static const stbi_uc stbi__zdefault_length[STBI__ZNSYMS] =
 {
    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
    8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
@@ -4363,7 +4406,7 @@ static int stbi__parse_zlib(stbi__zbuf *a, int parse_header)
       } else {
          if (type == 1) {
             // use fixed code lengths
-            if (!stbi__zbuild_huffman(&a->z_length  , stbi__zdefault_length  , 288)) return 0;
+            if (!stbi__zbuild_huffman(&a->z_length  , stbi__zdefault_length  , STBI__ZNSYMS)) return 0;
             if (!stbi__zbuild_huffman(&a->z_distance, stbi__zdefault_distance,  32)) return 0;
          } else {
             if (!stbi__compute_huffman_codes(a)) return 0;
@@ -4759,6 +4802,7 @@ static int stbi__create_png_image(stbi__png *a, stbi_uc *image_data, stbi__uint3
 
    // de-interlacing
    final = (stbi_uc *) stbi__malloc_mad3(a->s->img_x, a->s->img_y, out_bytes, 0);
+   if (!final) return stbi__err("outofmem", "Out of memory");
    for (p=0; p < 7; ++p) {
       int xorig[] = { 0,4,0,2,0,1,0 };
       int yorig[] = { 0,0,4,0,2,0,1 };
@@ -5394,8 +5438,7 @@ static void *stbi__bmp_load(stbi__context *s, int *x, int *y, int *comp, int req
          psize = (info.offset - info.extra_read - info.hsz) >> 2;
    }
    if (psize == 0) {
-      STBI_ASSERT(info.offset == s->callback_already_read + (int) (s->img_buffer - s->img_buffer_original));
-      if (info.offset != s->callback_already_read + (s->img_buffer - s->buffer_start)) {
+      if (info.offset != s->callback_already_read + (s->img_buffer - s->img_buffer_original)) {
         return stbi__errpuc("bad offset", "Corrupt BMP");
       }
    }
@@ -6342,6 +6385,7 @@ static void *stbi__pic_load(stbi__context *s,int *px,int *py,int *comp,int req_c
 
    // intermediate buffer is RGBA
    result = (stbi_uc *) stbi__malloc_mad3(x, y, 4, 0);
+   if (!result) return stbi__errpuc("outofmem", "Out of memory");
    memset(result, 0xff, x*y*4);
 
    if (!stbi__pic_load_core(s,x,y,comp, result)) {
@@ -6457,6 +6501,7 @@ static int stbi__gif_header(stbi__context *s, stbi__gif *g, int *comp, int is_in
 static int stbi__gif_info_raw(stbi__context *s, int *x, int *y, int *comp)
 {
    stbi__gif* g = (stbi__gif*) stbi__malloc(sizeof(stbi__gif));
+   if (!g) return stbi__err("outofmem", "Out of memory");
    if (!stbi__gif_header(s, g, comp, 1)) {
       STBI_FREE(g);
       stbi__rewind( s );
@@ -6766,6 +6811,17 @@ static stbi_uc *stbi__gif_load_next(stbi__context *s, stbi__gif *g, int *comp, i
    }
 }
 
+static void *stbi__load_gif_main_outofmem(stbi__gif *g, stbi_uc *out, int **delays)
+{
+   STBI_FREE(g->out);
+   STBI_FREE(g->history);
+   STBI_FREE(g->background);
+
+   if (out) STBI_FREE(out);
+   if (delays && *delays) STBI_FREE(*delays);
+   return stbi__errpuc("outofmem", "Out of memory");
+}
+
 static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y, int *z, int *comp, int req_comp)
 {
    if (stbi__gif_test(s)) {
@@ -6777,6 +6833,10 @@ static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y,
       int stride;
       int out_size = 0;
       int delays_size = 0;
+
+      STBI_NOTUSED(out_size);
+      STBI_NOTUSED(delays_size);
+
       memset(&g, 0, sizeof(g));
       if (delays) {
          *delays = 0;
@@ -6794,12 +6854,8 @@ static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y,
 
             if (out) {
                void *tmp = (stbi_uc*) STBI_REALLOC_SIZED( out, out_size, layers * stride );
-               if (NULL == tmp) {
-                  STBI_FREE(g.out);
-                  STBI_FREE(g.history);
-                  STBI_FREE(g.background);
-                  return stbi__errpuc("outofmem", "Out of memory");
-               }
+               if (!tmp)
+                  return stbi__load_gif_main_outofmem(&g, out, delays);
                else {
                    out = (stbi_uc*) tmp;
                    out_size = layers * stride;
@@ -6807,13 +6863,19 @@ static void *stbi__load_gif_main(stbi__context *s, int **delays, int *x, int *y,
 
                if (delays) {
                   *delays = (int*) STBI_REALLOC_SIZED( *delays, delays_size, sizeof(int) * layers );
+                  if (!*delays)
+                     return stbi__load_gif_main_outofmem(&g, out, delays);
                   delays_size = layers * sizeof(int);
                }
             } else {
                out = (stbi_uc*)stbi__malloc( layers * stride );
+               if (!out)
+                  return stbi__load_gif_main_outofmem(&g, out, delays);
                out_size = layers * stride;
                if (delays) {
                   *delays = (int*) stbi__malloc( layers * sizeof(int) );
+                  if (!*delays)
+                     return stbi__load_gif_main_outofmem(&g, out, delays);
                   delays_size = layers * sizeof(int);
                }
             }
@@ -7206,8 +7268,8 @@ static int stbi__psd_is16(stbi__context *s)
        stbi__rewind( s );
        return 0;
    }
-   (void) stbi__get32be(s);
-   (void) stbi__get32be(s);
+   STBI_NOTUSED(stbi__get32be(s));
+   STBI_NOTUSED(stbi__get32be(s));
    depth = stbi__get16be(s);
    if (depth != 16) {
        stbi__rewind( s );
@@ -7286,7 +7348,6 @@ static int stbi__pic_info(stbi__context *s, int *x, int *y, int *comp)
 // Known limitations:
 //    Does not support comments in the header section
 //    Does not support ASCII image data (formats P2 and P3)
-//    Does not support 16-bit-per-channel
 
 #ifndef STBI_NO_PNM
 
@@ -7307,7 +7368,8 @@ static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req
    stbi_uc *out;
    STBI_NOTUSED(ri);
 
-   if (!stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n))
+   ri->bits_per_channel = stbi__pnm_info(s, (int *)&s->img_x, (int *)&s->img_y, (int *)&s->img_n);
+   if (ri->bits_per_channel == 0)
       return 0;
 
    if (s->img_y > STBI_MAX_DIMENSIONS) return stbi__errpuc("too large","Very large image (corrupt?)");
@@ -7317,12 +7379,12 @@ static void *stbi__pnm_load(stbi__context *s, int *x, int *y, int *comp, int req
    *y = s->img_y;
    if (comp) *comp = s->img_n;
 
-   if (!stbi__mad3sizes_valid(s->img_n, s->img_x, s->img_y, 0))
+   if (!stbi__mad4sizes_valid(s->img_n, s->img_x, s->img_y, ri->bits_per_channel / 8, 0))
       return stbi__errpuc("too large", "PNM too large");
 
-   out = (stbi_uc *) stbi__malloc_mad3(s->img_n, s->img_x, s->img_y, 0);
+   out = (stbi_uc *) stbi__malloc_mad4(s->img_n, s->img_x, s->img_y, ri->bits_per_channel / 8, 0);
    if (!out) return stbi__errpuc("outofmem", "Out of memory");
-   stbi__getn(s, out, s->img_n * s->img_x * s->img_y);
+   stbi__getn(s, out, s->img_n * s->img_x * s->img_y * (ri->bits_per_channel / 8));
 
    if (req_comp && req_comp != s->img_n) {
       out = stbi__convert_format(out, s->img_n, req_comp, s->img_x, s->img_y);
@@ -7398,12 +7460,21 @@ static int      stbi__pnm_info(stbi__context *s, int *x, int *y, int *comp)
    stbi__pnm_skip_whitespace(s, &c);
 
    maxv = stbi__pnm_getinteger(s, &c);  // read max value
-
-   if (maxv > 255)
-      return stbi__err("max value > 255", "PPM image not 8-bit");
+   if (maxv > 65535)
+      return stbi__err("max value > 65535", "PPM image supports only 8-bit and 16-bit images");
+   else if (maxv > 255)
+      return 16;
    else
-      return 1;
+      return 8;
+}
+
+static int stbi__pnm_is16(stbi__context *s)
+{
+   if (stbi__pnm_info(s, NULL, NULL, NULL) == 16)
+	   return 1;
+   return 0;
 }
+
 #endif
 
 static int stbi__info_main(stbi__context *s, int *x, int *y, int *comp)
@@ -7458,6 +7529,9 @@ static int stbi__is_16_main(stbi__context *s)
    if (stbi__psd_is16(s))  return 1;
    #endif
 
+   #ifndef STBI_NO_PNM
+   if (stbi__pnm_is16(s))  return 1;
+   #endif
    return 0;
 }
 

stb_image_write.h

@@ -285,7 +285,7 @@ static void stbi__stdio_write(void *context, void *data, int size)
    fwrite(data,1,size,(FILE*) context);
 }
 
-#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+#if defined(_WIN32) && defined(STBI_WINDOWS_UTF8)
 #ifdef __cplusplus
 #define STBIW_EXTERN extern "C"
 #else
@@ -303,16 +303,16 @@ STBIWDEF int stbiw_convert_wchar_to_utf8(char *buffer, size_t bufferlen, const w
 static FILE *stbiw__fopen(char const *filename, char const *mode)
 {
    FILE *f;
-#if defined(_MSC_VER) && defined(STBI_WINDOWS_UTF8)
+#if defined(_WIN32) && defined(STBI_WINDOWS_UTF8)
    wchar_t wMode[64];
    wchar_t wFilename[1024];
-	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)))
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, filename, -1, wFilename, sizeof(wFilename)/sizeof(*wFilename)))
       return 0;
 
-	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)))
+	if (0 == MultiByteToWideChar(65001 /* UTF8 */, 0, mode, -1, wMode, sizeof(wMode)/sizeof(*wMode)))
       return 0;
 
-#if _MSC_VER >= 1400
+#if defined(_MSC_VER) && _MSC_VER >= 1400
 	if (0 != _wfopen_s(&f, wFilename, wMode))
 		f = 0;
 #else
@@ -397,7 +397,7 @@ static void stbiw__putc(stbi__write_context *s, unsigned char c)
 
 static void stbiw__write1(stbi__write_context *s, unsigned char a)
 {
-   if (s->buf_used + 1 > sizeof(s->buffer))
+   if ((size_t)s->buf_used + 1 > sizeof(s->buffer))
       stbiw__write_flush(s);
    s->buffer[s->buf_used++] = a;
 }
@@ -405,7 +405,7 @@ static void stbiw__write1(stbi__write_context *s, unsigned char a)
 static void stbiw__write3(stbi__write_context *s, unsigned char a, unsigned char b, unsigned char c)
 {
    int n;
-   if (s->buf_used + 3 > sizeof(s->buffer))
+   if ((size_t)s->buf_used + 3 > sizeof(s->buffer))
       stbiw__write_flush(s);
    n = s->buf_used;
    s->buf_used = n+3;

stb_sprintf.h

@@ -7,6 +7,7 @@
 //
 // Contributors:
 //    Fabian "ryg" Giesen (reformatting)
+//    github:aganm (attribute format)
 //
 // Contributors (bugfixes):
 //    github:d26435
@@ -176,7 +177,17 @@ PERFORMANCE vs MSVC 2008 32-/64-bit (GCC is even slower than MSVC):
 #endif
 #endif
 
-#include <stdarg.h> // for va_list()
+#if defined(__has_attribute)
+ #if __has_attribute(format)
+   #define STBSP__ATTRIBUTE_FORMAT(fmt,va) __attribute__((format(printf,fmt,va)))
+ #endif
+#endif
+
+#ifndef STBSP__ATTRIBUTE_FORMAT
+#define STBSP__ATTRIBUTE_FORMAT(fmt,va)
+#endif
+
+#include <stdarg.h> // for va_arg(), va_list()
 #include <stddef.h> // size_t, ptrdiff_t
 
 #ifndef STB_SPRINTF_MIN
@@ -190,8 +201,8 @@ typedef char *STBSP_SPRINTFCB(const char *buf, void *user, int len);
 
 STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(vsprintf)(char *buf, char const *fmt, va_list va);
 STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(vsnprintf)(char *buf, int count, char const *fmt, va_list va);
-STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(sprintf)(char *buf, char const *fmt, ...);
-STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(snprintf)(char *buf, int count, char const *fmt, ...);
+STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(sprintf)(char *buf, char const *fmt, ...) STBSP__ATTRIBUTE_FORMAT(2,3);
+STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(snprintf)(char *buf, int count, char const *fmt, ...) STBSP__ATTRIBUTE_FORMAT(3,4);
 
 STBSP__PUBLICDEF int STB_SPRINTF_DECORATE(vsprintfcb)(STBSP_SPRINTFCB *callback, void *user, char *buf, char const *fmt, va_list va);
 STBSP__PUBLICDEF void STB_SPRINTF_DECORATE(set_separators)(char comma, char period);
@@ -200,8 +211,6 @@ STBSP__PUBLICDEF void STB_SPRINTF_DECORATE(set_separators)(char comma, char peri
 
 #ifdef STB_SPRINTF_IMPLEMENTATION
 
-#include <stdlib.h> // for va_arg()
-
 #define stbsp__uint32 unsigned int
 #define stbsp__int32 signed int
 
@@ -215,7 +224,7 @@ STBSP__PUBLICDEF void STB_SPRINTF_DECORATE(set_separators)(char comma, char peri
 #define stbsp__uint16 unsigned short
 
 #ifndef stbsp__uintptr
-#if defined(__ppc64__) || defined(__powerpc64__) || defined(__aarch64__) || defined(_M_X64) || defined(__x86_64__) || defined(__x86_64)
+#if defined(__ppc64__) || defined(__powerpc64__) || defined(__aarch64__) || defined(_M_X64) || defined(__x86_64__) || defined(__x86_64) || defined(__s390x__)
 #define stbsp__uintptr stbsp__uint64
 #else
 #define stbsp__uintptr stbsp__uint32
@@ -1588,7 +1597,7 @@ static stbsp__uint64 const stbsp__powten[20] = {
 #define stbsp__ddtoS64(ob, xh, xl)          \
    {                                        \
       double ahi = 0, alo, vh, t;           \
-      ob = (stbsp__int64)ph;                \
+      ob = (stbsp__int64)xh;                \
       vh = (double)ob;                      \
       ahi = (xh - vh);                      \
       t = (ahi - xh);                       \

stb_textedit.h

@@ -87,8 +87,8 @@
 //   moderate sizes. The undo system does no memory allocations, so
 //   it grows STB_TexteditState by the worst-case storage which is (in bytes):
 //
-//        [4 + 3 * sizeof(STB_TEXTEDIT_POSITIONTYPE)] * STB_TEXTEDIT_UNDOSTATE_COUNT
-//      +          sizeof(STB_TEXTEDIT_CHARTYPE)      * STB_TEXTEDIT_UNDOCHAR_COUNT
+//        [4 + 3 * sizeof(STB_TEXTEDIT_POSITIONTYPE)] * STB_TEXTEDIT_UNDOSTATECOUNT
+//      +          sizeof(STB_TEXTEDIT_CHARTYPE)      * STB_TEXTEDIT_UNDOCHARCOUNT
 //
 //
 // Implementation mode:

stb_truetype.h

@@ -297,6 +297,8 @@ void my_stbtt_initfont(void)
 void my_stbtt_print(float x, float y, char *text)
 {
    // assume orthographic projection with units = screen pixels, origin at top left
+   glEnable(GL_BLEND);
+   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, ftex);
    glBegin(GL_QUADS);
@@ -1539,12 +1541,12 @@ STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codep
       search += 2;
 
       {
-         stbtt_uint16 offset, start;
+         stbtt_uint16 offset, start, last;
          stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1);
 
-         STBTT_assert(unicode_codepoint <= ttUSHORT(data + endCount + 2*item));
          start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item);
-         if (unicode_codepoint < start)
+         last = ttUSHORT(data + endCount + 2*item);
+         if (unicode_codepoint < start || unicode_codepoint > last)
             return 0;
 
          offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item);

tests/test_vorbis.c

@@ -8,7 +8,7 @@ extern void stb_vorbis_dumpmem(void);
 int main(int argc, char **argv)
 {
    size_t memlen;
-   unsigned char *mem = stb_fileu("c:/x/sketch008.ogg", &memlen);
+   unsigned char *mem = stb_fileu("../../lib/vorbis/sample/sketch008.ogg", &memlen);
    int chan, samplerate;
    short *output;
    int samples = stb_vorbis_decode_memory(mem, memlen, &chan, &samplerate, &output);