Added explicit support for sRGB framebuffers.

include/GL/glfw3.h

@@ -518,6 +518,10 @@ extern "C" {
 /*! @brief The number of samples used for default framebuffer multisampling.
  */
 #define GLFW_FSAA_SAMPLES         0x0002100E
+/*! @brief @c GL_TRUE if the framebuffer should be sRGB capable, or @c GL_FALSE
+ *  otherwise.
+ */
+#define GLFW_SRGB_CAPABLE         0x0002100F
 
 /*! @brief The @link clients client API @endlink to create a context for.
  */
@@ -1020,6 +1024,9 @@ GLFWAPI void glfwDefaultWindowHints(void);
  *  The @ref GLFW_FSAA_SAMPLES hint specifies the desired number of samples to
  *  use for multisampling.
  *
+ *  The @ref GLFW_SRGB_CAPABLE hint specifies whether the framebuffer should be
+ *  sRGB capable.
+ *
  *  The @ref GLFW_CLIENT_API hint specifies which client API to create the
  *  context for.  Possible values are @ref GLFW_OPENGL_API and @ref
  *  GLFW_OPENGL_ES_API.

src/cocoa_window.m

@@ -835,6 +835,9 @@ static GLboolean createContext(_GLFWwindow* window,
         ADD_ATTR2(NSOpenGLPFASamples, fbconfig->samples);
     }
 
+    // NOTE: All NSOpenGLPixelFormats on the relevant cards support sRGB
+    // frambuffer, so there's no need (and no way) to request it
+
     ADD_ATTR(0);
 
 #undef ADD_ATTR

src/internal.h

@@ -100,6 +100,7 @@ struct _GLFWhints
     GLboolean   resizable;
     GLboolean   visible;
     int         samples;
+    GLboolean   sRGB;
     int         clientAPI;
     int         glMajor;
     int         glMinor;
@@ -160,6 +161,7 @@ struct _GLFWfbconfig
     int         auxBuffers;
     GLboolean   stereo;
     int         samples;
+    GLboolean   sRGB;
     GLFWintptr  platformID;
 };
 

src/opengl.c

@@ -217,6 +217,12 @@ const _GLFWfbconfig* _glfwChooseFBConfig(const _GLFWfbconfig* desired,
                 extraDiff += (desired->samples - current->samples) *
                              (desired->samples - current->samples);
             }
+
+            if (desired->sRGB)
+            {
+                if (!current->sRGB)
+                    extraDiff++;
+            }
         }
 
         // Figure out if the current one is better than the best one found so far

src/win32_opengl.c

@@ -72,6 +72,7 @@ static void initWGLExtensions(_GLFWwindow* window)
     // This needs to include every extension used below except for
     // WGL_ARB_extensions_string and WGL_EXT_extensions_string
     window->WGL.ARB_multisample = GL_FALSE;
+    window->WGL.ARB_framebuffer_sRGB = GL_FALSE;
     window->WGL.ARB_create_context = GL_FALSE;
     window->WGL.ARB_create_context_profile = GL_FALSE;
     window->WGL.EXT_create_context_es2_profile = GL_FALSE;
@@ -92,6 +93,9 @@ static void initWGLExtensions(_GLFWwindow* window)
     if (_glfwPlatformExtensionSupported("WGL_ARB_multisample"))
         window->WGL.ARB_multisample = GL_TRUE;
 
+    if (_glfwPlatformExtensionSupported("WGL_ARB_framebuffer_sRGB"))
+        window->WGL.ARB_framebuffer_sRGB = GL_TRUE;
+
     if (_glfwPlatformExtensionSupported("WGL_ARB_create_context"))
     {
         window->WGL.CreateContextAttribsARB = (PFNWGLCREATECONTEXTATTRIBSARBPROC)
@@ -246,6 +250,11 @@ static _GLFWfbconfig* getFBConfigs(_GLFWwindow* window, unsigned int* found)
                 f->samples = getPixelFormatAttrib(window, i, WGL_SAMPLES_ARB);
             else
                 f->samples = 0;
+
+            if (window->WGL.ARB_framebuffer_sRGB)
+                f->sRGB = getPixelFormatAttrib(window, i, WGL_FRAMEBUFFER_SRGB_CAPABLE_ARB);
+            else
+                f->sRGB = GL_FALSE;
         }
         else
         {
@@ -293,6 +302,9 @@ static _GLFWfbconfig* getFBConfigs(_GLFWwindow* window, unsigned int* found)
 
             // PFD pixel formats do not support FSAA
             f->samples = 0;
+
+            // PFD pixel formats do not support sRGB
+            f->sRGB = GL_FALSE;
         }
 
         f->platformID = i;

src/win32_platform.h

@@ -144,6 +144,7 @@ typedef struct _GLFWcontextWGL
     GLboolean                           EXT_swap_control;
     GLboolean                           ARB_multisample;
     GLboolean                           ARB_pixel_format;
+    GLboolean                           ARB_framebuffer_sRGB;
     GLboolean                           ARB_create_context;
     GLboolean                           ARB_create_context_profile;
     GLboolean                           EXT_create_context_es2_profile;

src/window.c

@@ -237,6 +237,7 @@ GLFWAPI GLFWwindow glfwCreateWindow(int width, int height,
     fbconfig.auxBuffers     = Max(_glfwLibrary.hints.auxBuffers, 0);
     fbconfig.stereo         = _glfwLibrary.hints.stereo ? GL_TRUE : GL_FALSE;
     fbconfig.samples        = Max(_glfwLibrary.hints.samples, 0);
+    fbconfig.sRGB           = _glfwLibrary.hints.sRGB ? GL_TRUE : GL_FALSE;
 
     // Set up desired window config
     wndconfig.mode           = mode;
@@ -446,6 +447,9 @@ GLFWAPI void glfwWindowHint(int target, int hint)
         case GLFW_FSAA_SAMPLES:
             _glfwLibrary.hints.samples = hint;
             break;
+        case GLFW_SRGB_CAPABLE:
+            _glfwLibrary.hints.sRGB = hint;
+            break;
         case GLFW_CLIENT_API:
             _glfwLibrary.hints.clientAPI = hint;
             break;

src/x11_opengl.c

@@ -190,6 +190,11 @@ static _GLFWfbconfig* getFBConfigs(_GLFWwindow* window, unsigned int* found)
         else
             f->samples = 0;
 
+        if (_glfwLibrary.GLX.ARB_framebuffer_sRGB)
+            f->sRGB = getFBConfigAttrib(window, fbconfigs[i], GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB);
+        else
+            f->sRGB = GL_FALSE;
+
         f->platformID = (GLFWintptr) getFBConfigAttrib(window, fbconfigs[i], GLX_FBCONFIG_ID);
 
         (*found)++;
@@ -527,6 +532,9 @@ int _glfwInitOpenGL(void)
     if (_glfwPlatformExtensionSupported("GLX_ARB_multisample"))
         _glfwLibrary.GLX.ARB_multisample = GL_TRUE;
 
+    if (_glfwPlatformExtensionSupported("GLX_ARB_framebuffer_sRGB"))
+        _glfwLibrary.GLX.ARB_framebuffer_sRGB = GL_TRUE;
+
     if (_glfwPlatformExtensionSupported("GLX_ARB_create_context"))
     {
         _glfwLibrary.GLX.CreateContextAttribsARB = (PFNGLXCREATECONTEXTATTRIBSARBPROC)

src/x11_platform.h

@@ -272,6 +272,7 @@ typedef struct _GLFWlibraryGLX
     GLboolean   EXT_swap_control;
     GLboolean   MESA_swap_control;
     GLboolean   ARB_multisample;
+    GLboolean   ARB_framebuffer_sRGB;
     GLboolean   ARB_create_context;
     GLboolean   ARB_create_context_profile;
     GLboolean   ARB_create_context_robustness;