Added SDL_GL_FRAMEBUFFER_SRGB_CAPABLE (thanks, David!).

Fixes Bugzilla #1985.

include/SDL_video.h

@@ -187,7 +187,8 @@ typedef enum
     SDL_GL_CONTEXT_EGL,
     SDL_GL_CONTEXT_FLAGS,
     SDL_GL_CONTEXT_PROFILE_MASK,
-    SDL_GL_SHARE_WITH_CURRENT_CONTEXT
+    SDL_GL_SHARE_WITH_CURRENT_CONTEXT,
+    SDL_GL_FRAMEBUFFER_SRGB_CAPABLE
 } SDL_GLattr;
 
 typedef enum

src/video/SDL_sysvideo.h

@@ -293,6 +293,7 @@ struct SDL_VideoDevice
         int flags;
         int profile_mask;
         int share_with_current_context;
+        int framebuffer_srgb_capable;
         int retained_backing;
         int driver_loaded;
         char driver_path[256];

src/video/SDL_video.c

@@ -2570,7 +2570,10 @@ SDL_GL_SetAttribute(SDL_GLattr attr, int value)
         break;
     case SDL_GL_SHARE_WITH_CURRENT_CONTEXT:
         _this->gl_config.share_with_current_context = value;
-    break;
+        break;
+    case SDL_GL_FRAMEBUFFER_SRGB_CAPABLE:
+        _this->gl_config.framebuffer_srgb_capable = value;
+        break;
     default:
         retval = SDL_SetError("Unknown OpenGL attribute");
         break;
@@ -2741,6 +2744,11 @@ SDL_GL_GetAttribute(SDL_GLattr attr, int *value)
             *value = _this->gl_config.share_with_current_context;
             return 0;
         }
+    case SDL_GL_FRAMEBUFFER_SRGB_CAPABLE:
+        {
+            *value = _this->gl_config.framebuffer_srgb_capable;
+            return 0;
+        }
     default:
         return SDL_SetError("Unknown OpenGL attribute");
     }

src/video/windows/SDL_windowsopengl.c

@@ -67,6 +67,11 @@
 #define WGL_CONTEXT_ES_PROFILE_BIT_EXT            0x00000004
 #endif
 
+#ifndef WGL_ARB_framebuffer_sRGB
+#define WGL_ARB_framebuffer_sRGB
+#define WGL_FRAMEBUFFER_SRGB_CAPABLE_ARB                0x20A9
+#endif
+
 typedef HGLRC(APIENTRYP PFNWGLCREATECONTEXTATTRIBSARBPROC) (HDC hDC,
                                                             HGLRC
                                                             hShareContext,
@@ -495,6 +500,11 @@ WIN_GL_SetupWindowInternal(_THIS, SDL_Window * window)
         *iAttr++ = _this->gl_config.multisamplesamples;
     }
 
+    if (_this->gl_config.framebuffer_srgb_capable) {
+        *iAttr++ = WGL_FRAMEBUFFER_SRGB_CAPABLE_ARB;
+        *iAttr++ = _this->gl_config.framebuffer_srgb_capable;
+    }
+
     /* We always choose either FULL or NO accel on Windows, because of flaky
        drivers. If the app didn't specify, we use FULL, because that's
        probably what they wanted (and if you didn't care and got FULL, that's

src/video/x11/SDL_x11opengl.c

@@ -106,6 +106,13 @@ typedef GLXContext(*PFNGLXCREATECONTEXTATTRIBSARBPROC) (Display * dpy,
 #endif
 #endif
 
+#ifndef GLX_ARB_framebuffer_sRGB
+#define GLX_ARB_framebuffer_sRGB
+#ifndef GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB
+#define GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB                0x20B2
+#endif
+#endif
+
 #ifndef GLX_EXT_swap_control
 #define GLX_SWAP_INTERVAL_EXT              0x20F1
 #define GLX_MAX_SWAP_INTERVAL_EXT          0x20F2
@@ -472,6 +479,13 @@ X11_GL_GetAttributes(_THIS, Display * display, int screen, int * attribs, int si
         attribs[i++] = _this->gl_config.multisamplesamples;
     }
 
+    if (_this->gl_config.framebuffer_srgb_capable) {
+        attribs[i++] = GLX_FRAMEBUFFER_SRGB_CAPABLE_ARB;
+        if( for_FBConfig ) {
+            attribs[i++] = True;
+        }
+    }
+
     if (_this->gl_config.accelerated >= 0 &&
         _this->gl_data->HAS_GLX_EXT_visual_rating) {
         attribs[i++] = GLX_VISUAL_CAVEAT_EXT;