Full support of sRGB capable fbconfigs.

Changes to correctly initialize the sRGB capability attribute and
transfer it between XServer and the client. Modifications include
extension string, transferring visual config attribs and fbconfig
attribs. Also, attribute is initialized in the modules which do not
really use it (xquartz and xwin).
This version advertises both ARB and EXT strings, and initializes
the capability to default value of FALSE. It has corrected required
GLX version and does not influence swrast. The sRGB capable attribute
is attached only to those configs which do have this capability.
Both ARB and EXT versions share the same GLX extension enabling bit.

Signed-off-by: Tomasz Lis <tomasz.lis@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>

glx/extension_string.c

@@ -71,9 +71,11 @@ static const struct extension_info known_glx_extensions[] = {
     { GLX(ARB_create_context),          VER(0,0), N, },
     { GLX(ARB_create_context_profile),  VER(0,0), N, },
     { GLX(ARB_create_context_robustness), VER(0,0), N, },
+    { GLX(ARB_framebuffer_sRGB),        VER(0,0), N, },
     { GLX(ARB_multisample),             VER(1,4), Y, },
 
     { GLX(EXT_create_context_es2_profile), VER(0,0), N, },
+    { GLX(EXT_framebuffer_sRGB),        VER(0,0), N, },
     { GLX(EXT_import_context),          VER(0,0), Y, },
     { GLX(EXT_texture_from_pixmap),     VER(0,0), Y, },
     { GLX(EXT_visual_info),             VER(0,0), Y, },

glx/extension_string.h

@@ -39,6 +39,7 @@ enum {
     ARB_create_context_bit = 0,
     ARB_create_context_profile_bit,
     ARB_create_context_robustness_bit,
+    ARB_framebuffer_sRGB_bit,
     ARB_multisample_bit,
     EXT_create_context_es2_profile_bit,
     EXT_import_context_bit,
@@ -58,6 +59,10 @@ enum {
     __NUM_GLX_EXTS,
 };
 
+/* For extensions which have identical ARB and EXT implementation
+ * in GLX area, use one enabling bit for both. */
+#define EXT_framebuffer_sRGB_bit ARB_framebuffer_sRGB_bit
+
 #define __GLX_EXT_BYTES ((__NUM_GLX_EXTS + 7) / 8)
 
 extern int __glXGetExtensionString(const unsigned char *enable_bits,

glx/glxcmds.c

@@ -913,7 +913,7 @@ __glXDisp_CopyContext(__GLXclientState * cl, GLbyte * pc)
 
 enum {
     GLX_VIS_CONFIG_UNPAIRED = 18,
-    GLX_VIS_CONFIG_PAIRED = 20
+    GLX_VIS_CONFIG_PAIRED = 22
 };
 
 enum {
@@ -1005,8 +1005,17 @@ __glXDisp_GetVisualConfigs(__GLXclientState * cl, GLbyte * pc)
         buf[p++] = modes->samples;
         buf[p++] = GLX_SAMPLE_BUFFERS_SGIS;
         buf[p++] = modes->sampleBuffers;
-        buf[p++] = 0;           /* copy over visualSelectGroup (GLX_VISUAL_SELECT_GROUP_SGIX)? */
+        /* Add attribute only if its value is not default. */
+        if (modes->sRGBCapable != GL_FALSE) {
+            buf[p++] = GLX_FRAMEBUFFER_SRGB_CAPABLE_EXT;
+            buf[p++] = modes->sRGBCapable;
+        }
+        /* Don't add visualSelectGroup (GLX_VISUAL_SELECT_GROUP_SGIX)?
+         * Pad the remaining place with zeroes, so that attributes count is constant. */
+        while (p < GLX_VIS_CONFIG_TOTAL) {
             buf[p++] = 0;
+            buf[p++] = 0;
+        }
 
         assert(p == GLX_VIS_CONFIG_TOTAL);
         if (client->swapped) {
@@ -1017,7 +1026,7 @@ __glXDisp_GetVisualConfigs(__GLXclientState * cl, GLbyte * pc)
     return Success;
 }
 
-#define __GLX_TOTAL_FBCONFIG_ATTRIBS (36)
+#define __GLX_TOTAL_FBCONFIG_ATTRIBS (37)
 #define __GLX_FBCONFIG_ATTRIBS_LENGTH (__GLX_TOTAL_FBCONFIG_ATTRIBS * 2)
 /**
  * Send the set of GLXFBConfigs to the client.  There is not currently
@@ -1109,6 +1118,15 @@ DoGetFBConfigs(__GLXclientState * cl, unsigned screen)
         WRITE_PAIR(GLX_BIND_TO_MIPMAP_TEXTURE_EXT, modes->bindToMipmapTexture);
         WRITE_PAIR(GLX_BIND_TO_TEXTURE_TARGETS_EXT,
                    modes->bindToTextureTargets);
+        /* Add attribute only if its value is not default. */
+        if (modes->sRGBCapable != GL_FALSE) {
+            WRITE_PAIR(GLX_FRAMEBUFFER_SRGB_CAPABLE_EXT, modes->sRGBCapable);
+        }
+        /* Pad the remaining place with zeroes, so that attributes count is constant. */
+        while (p < __GLX_FBCONFIG_ATTRIBS_LENGTH) {
+            WRITE_PAIR(0, 0);
+        }
+        assert(p == __GLX_FBCONFIG_ATTRIBS_LENGTH);
 
         if (client->swapped) {
             __GLX_SWAP_INT_ARRAY(buf, __GLX_FBCONFIG_ATTRIBS_LENGTH);

glx/glxdri2.c

@@ -882,6 +882,13 @@ initializeExtensions(__GLXDRIscreen * screen)
                    "AIGLX: enabled GLX_SGI_swap_control and GLX_MESA_swap_control\n");
     }
 
+    /* enable EXT_framebuffer_sRGB extension (even if there are no sRGB capable fbconfigs) */
+    {
+        __glXEnableExtension(screen->glx_enable_bits,
+                 "GLX_EXT_framebuffer_sRGB");
+        LogMessage(X_INFO, "AIGLX: enabled GLX_EXT_framebuffer_sRGB\n");
+    }
+
     for (i = 0; extensions[i]; i++) {
 #ifdef __DRI_READ_DRAWABLE
         if (strcmp(extensions[i]->name, __DRI_READ_DRAWABLE) == 0) {

glx/glxdricommon.c

@@ -105,7 +105,9 @@ __ATTRIB(__DRI_ATTRIB_BUFFER_SIZE, rgbBits),
         __ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_RGB, bindToTextureRgb),
         __ATTRIB(__DRI_ATTRIB_BIND_TO_TEXTURE_RGBA, bindToTextureRgba),
         __ATTRIB(__DRI_ATTRIB_BIND_TO_MIPMAP_TEXTURE, bindToMipmapTexture),
-        __ATTRIB(__DRI_ATTRIB_YINVERTED, yInverted),};
+        __ATTRIB(__DRI_ATTRIB_YINVERTED, yInverted),
+        __ATTRIB(__DRI_ATTRIB_FRAMEBUFFER_SRGB_CAPABLE, sRGBCapable),
+        };
 
 static void
 setScalar(__GLXconfig * config, unsigned int attrib, unsigned int value)

glx/glxscreens.h

@@ -102,6 +102,9 @@ struct __GLXconfig {
     GLint bindToMipmapTexture;
     GLint bindToTextureTargets;
     GLint yInverted;
+
+    /* ARB_framebuffer_sRGB */
+    GLint sRGBCapable;
 };
 
 GLint glxConvertToXVisualType(int visualType);

hw/xquartz/GL/visualConfigs.c

@@ -262,6 +262,9 @@ __GLXconfig *__glXAquaCreateVisualConfigs(int *numConfigsPtr, int screenNumber)
                                         c->bindToTextureTargets = 0;
                                         c->yInverted = 0;
 
+                                        /* EXT_framebuffer_sRGB */
+                                        c->sRGBCapable = GL_FALSE;
+
                                         c = c->next;
                                     }
                                 }

hw/xwin/glx/indirect.c

@@ -2025,6 +2025,7 @@ glxWinCreateConfigs(HDC hdc, glxWinScreen * screen)
         c->base.bindToMipmapTexture = -1;
         c->base.bindToTextureTargets = -1;
         c->base.yInverted = -1;
+        c->base.sRGBCapable = 0;
 
         n++;
 
@@ -2419,6 +2420,7 @@ glxWinCreateConfigsExt(HDC hdc, glxWinScreen * screen)
             GLX_TEXTURE_1D_BIT_EXT | GLX_TEXTURE_2D_BIT_EXT |
             GLX_TEXTURE_RECTANGLE_BIT_EXT;
         c->base.yInverted = -1;
+        c->base.sRGBCapable = 0;
 
         n++;