Reviewed window initialization

In case graphic device could not be created it returns false instead of
failing with an error tracelog (and consequently closing the program).
Window initialization success could be checked with new function
IsWindowReady()

src/core.c

@@ -236,7 +236,8 @@
 static GLFWwindow *window;                      // Native window (graphic device)
 #endif
 
-static bool windowMinimized = false;
+static bool windowReady = false;                // Check if window has been initialized successfully
+static bool windowMinimized = false;            // Check if window has been minimized
 
 #if defined(PLATFORM_ANDROID)
 static struct android_app *app;                 // Android activity
@@ -244,7 +245,6 @@ static struct android_poll_source *source;      // Android events polling source
 static int ident, events;                       // Android ALooper_pollAll() variables
 static const char *internalDataPath;            // Android internal data path to write data (/data/data/<package>/files)
 
-static bool windowReady = false;                // Used to detect display initialization
 static bool appEnabled = true;                  // Used to detec if app is active
 static bool contextRebindRequired = false;      // Used to know context rebind required
 #endif
@@ -429,7 +429,7 @@ static void *GamepadThread(void *arg);                  // Mouse reading thread
 #if defined(PLATFORM_DESKTOP) || defined(PLATFORM_RPI) || defined(PLATFORM_WEB) || defined(PLATFORM_UWP)
 // Initialize window and OpenGL context
 // NOTE: data parameter could be used to pass any kind of required data to the initialization
-bool InitWindow(int width, int height, void *data)
+void InitWindow(int width, int height, void *data)
 {
     TraceLog(LOG_INFO, "Initializing raylib (v1.9-dev)");
 
@@ -442,9 +442,9 @@ bool InitWindow(int width, int height, void *data)
 #endif
 
     // Init graphics device (display device and OpenGL context)
-    if (!InitGraphicsDevice(width, height))
-        return false;
-    
+    // NOTE: returns true if window and graphic device has been initialized successfully
+    windowReady = InitGraphicsDevice(width, height);
+
     // Init hi-res timer
     InitTimer();
 
@@ -493,14 +493,13 @@ bool InitWindow(int width, int height, void *data)
         SetTargetFPS(60);
         LogoAnimation();
     }
-    return true;
 }
 #endif
 
 #if defined(PLATFORM_ANDROID)
 // Initialize window and OpenGL context (and Android activity)
 // NOTE: data parameter could be used to pass any kind of required data to the initialization
-bool InitWindow(int width, int height, void *data)
+void InitWindow(int width, int height, void *data)
 {
     TraceLog(LOG_INFO, "Initializing raylib (v1.9-dev)");
 
@@ -557,7 +556,6 @@ bool InitWindow(int width, int height, void *data)
             //if (app->destroyRequested != 0) windowShouldClose = true;
         }
     }
-    return true;
 }
 #endif
 
@@ -625,6 +623,12 @@ void CloseWindow(void)
     TraceLog(LOG_INFO, "Window closed successfully");
 }
 
+// Check if window has been initialized successfully
+bool IsWindowReady(void)
+{
+    return windowReady;
+}
+
 // Check if KEY_ESCAPE pressed or Close icon pressed
 bool WindowShouldClose(void)
 {
@@ -1700,6 +1704,7 @@ Vector2 GetTouchPosition(int index)
 // Initialize display device and framebuffer
 // NOTE: width and height represent the screen (framebuffer) desired size, not actual display size
 // If width or height are 0, default display size will be used for framebuffer size
+// NOTE: returns false in case graphic device could not be created
 static bool InitGraphicsDevice(int width, int height)
 {
     screenWidth = width;        // User desired width
@@ -1998,7 +2003,11 @@ static bool InitGraphicsDevice(int width, int height)
 
     // eglGetPlatformDisplayEXT is an alternative to eglGetDisplay. It allows us to pass in display attributes, used to configure D3D11.
     PFNEGLGETPLATFORMDISPLAYEXTPROC eglGetPlatformDisplayEXT = (PFNEGLGETPLATFORMDISPLAYEXTPROC)(eglGetProcAddress("eglGetPlatformDisplayEXT"));
-    if (!eglGetPlatformDisplayEXT) TraceLog(LOG_ERROR, "Failed to get function eglGetPlatformDisplayEXT");
+    if (!eglGetPlatformDisplayEXT)
+    {
+        TraceLog(LOG_WARNING, "Failed to get function eglGetPlatformDisplayEXT");
+        return false;
+    }
 
     //
     // To initialize the display, we make three sets of calls to eglGetPlatformDisplayEXT and eglInitialize, with varying 
@@ -2012,24 +2021,37 @@ static bool InitGraphicsDevice(int width, int height)
     
     // This tries to initialize EGL to D3D11 Feature Level 10_0+. See above comment for details.
     display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, EGL_DEFAULT_DISPLAY, defaultDisplayAttributes);
-    if (display == EGL_NO_DISPLAY) TraceLog(LOG_ERROR, "Failed to get EGL display");
-
+    if (display == EGL_NO_DISPLAY)
+    {
+        TraceLog(LOG_WARNING, "Failed to initialize EGL display");
+        return false;
+    }
+        
     if (eglInitialize(display, NULL, NULL) == EGL_FALSE)
     {
         // This tries to initialize EGL to D3D11 Feature Level 9_3, if 10_0+ is unavailable (e.g. on some mobile devices).
         display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, EGL_DEFAULT_DISPLAY, fl9_3DisplayAttributes);
-        if (display == EGL_NO_DISPLAY) TraceLog(LOG_ERROR, "Failed to get EGL display");
+        if (display == EGL_NO_DISPLAY)
+        {
+            TraceLog(LOG_WARNING, "Failed to initialize EGL display");
+            return false;
+        }
 
         if (eglInitialize(display, NULL, NULL) == EGL_FALSE)
         {
             // This initializes EGL to D3D11 Feature Level 11_0 on WARP, if 9_3+ is unavailable on the default GPU.
             display = eglGetPlatformDisplayEXT(EGL_PLATFORM_ANGLE_ANGLE, EGL_DEFAULT_DISPLAY, warpDisplayAttributes);
-            if (display == EGL_NO_DISPLAY) TraceLog(LOG_ERROR, "Failed to get EGL display");
+            if (display == EGL_NO_DISPLAY) 
+            {
+                TraceLog(LOG_WARNING, "Failed to initialize EGL display");
+                return false;
+            }
 
             if (eglInitialize(display, NULL, NULL) == EGL_FALSE)
             {
                 // If all of the calls to eglInitialize returned EGL_FALSE then an error has occurred.
-                TraceLog(LOG_ERROR, "Failed to initialize EGL");
+                TraceLog(LOG_WARNING, "Failed to initialize EGL");
+                return false;
             }
         }
     }
@@ -2039,7 +2061,8 @@ static bool InitGraphicsDevice(int width, int height)
     EGLint numConfigs = 0;
     if ((eglChooseConfig(display, framebufferAttribs, &config, 1, &numConfigs) == EGL_FALSE) || (numConfigs == 0))
     {
-        TraceLog(LOG_ERROR, "Failed to choose first EGLConfig");
+        TraceLog(LOG_WARNING, "Failed to choose first EGLConfig");
+        return false;
     }
 
     // Create a PropertySet and initialize with the EGLNativeWindowType.
@@ -2074,10 +2097,18 @@ static bool InitGraphicsDevice(int width, int height)
     
     //surface = eglCreateWindowSurface(display, config, reinterpret_cast<IInspectable*>(surfaceCreationProperties), surfaceAttributes);
     surface = eglCreateWindowSurface(display, config, uwpWindow, surfaceAttributes);
-    if (surface == EGL_NO_SURFACE) TraceLog(LOG_ERROR, "Failed to create EGL fullscreen surface");
+    if (surface == EGL_NO_SURFACE)
+    {
+        TraceLog(LOG_WARNING, "Failed to create EGL fullscreen surface");
+        return false;
+    }
 
     context = eglCreateContext(display, config, EGL_NO_CONTEXT, contextAttribs);
-    if (context == EGL_NO_CONTEXT) TraceLog(LOG_ERROR, "Failed to create EGL context");
+    if (context == EGL_NO_CONTEXT)
+    {
+        TraceLog(LOG_WARNING, "Failed to create EGL context");
+        return false;
+    }
 
 	// Get EGL display window size 
 	eglQuerySurface(display, surface, EGL_WIDTH, &screenWidth);
@@ -2088,9 +2119,19 @@ static bool InitGraphicsDevice(int width, int height)
 
     // Get an EGL display connection
     display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
+    if (display == EGL_NO_DISPLAY) 
+    {
+        TraceLog(LOG_WARNING, "Failed to initialize EGL display");
+        return false;
+    }
 
     // Initialize the EGL display connection
-    eglInitialize(display, NULL, NULL);
+    if (eglInitialize(display, NULL, NULL) == EGL_FALSE)
+    {
+        // If all of the calls to eglInitialize returned EGL_FALSE then an error has occurred.
+        TraceLog(LOG_WARNING, "Failed to initialize EGL");
+        return false;
+    }
 
     // Get an appropriate EGL framebuffer configuration
     eglChooseConfig(display, framebufferAttribs, &config, 1, &numConfigs);
@@ -2100,6 +2141,11 @@ static bool InitGraphicsDevice(int width, int height)
 
     // Create an EGL rendering context
     context = eglCreateContext(display, config, EGL_NO_CONTEXT, contextAttribs);
+    if (context == EGL_NO_CONTEXT)
+    {
+        TraceLog(LOG_WARNING, "Failed to create EGL context");
+        return false;
+    }
 #endif
 
     // Create an EGL window surface
@@ -2168,7 +2214,8 @@ static bool InitGraphicsDevice(int width, int height)
 
     if (eglMakeCurrent(display, surface, surface, context) == EGL_FALSE)
     {
-        TraceLog(LOG_ERROR, "Unable to attach EGL rendering context to EGL surface");
+        TraceLog(LOG_WARNING, "Unable to attach EGL rendering context to EGL surface");
+        return false;
     }
     else
     {

src/raylib.h

@@ -684,8 +684,9 @@ extern "C" {            // Prevents name mangling of functions
 //------------------------------------------------------------------------------------
 
 // Window-related functions
-RLAPI bool InitWindow(int width, int height, void *data);         // Initialize window and OpenGL context
+RLAPI void InitWindow(int width, int height, void *data);         // Initialize window and OpenGL context
 RLAPI void CloseWindow(void);                                     // Close window and unload OpenGL context
+RLAPI bool IsWindowReady(void);                                   // Check if window has been initialized successfully
 RLAPI bool WindowShouldClose(void);                               // Check if KEY_ESCAPE pressed or Close icon pressed
 RLAPI bool IsWindowMinimized(void);                               // Check if window has been minimized (or lost focus)
 RLAPI void ToggleFullscreen(void);                                // Toggle fullscreen mode (only PLATFORM_DESKTOP)