Bug 1048693 - WebGL2 - GL symbols for MapBufferRange.; r=jgilbert

--HG--
extra : source : 60f8018abde66d8ec07329fabaa0a7131acf84da
extra : histedit_source : b4fa1e2d81c7c007479ae2409233a600fc75c257

gfx/gl/GLContext.cpp

@@ -85,6 +85,7 @@ static const char *sExtensionNames[] = {
     "GL_ARB_framebuffer_sRGB",
     "GL_ARB_half_float_pixel",
     "GL_ARB_instanced_arrays",
+    "GL_ARB_map_buffer_range",
     "GL_ARB_occlusion_query2",
     "GL_ARB_pixel_buffer_object",
     "GL_ARB_robustness",
@@ -1086,6 +1087,21 @@ GLContext::InitWithPrefix(const char *prefix, bool trygl)
             }
         }
 
+        if (IsSupported(GLFeature::map_buffer_range)) {
+            SymLoadStruct mapBufferRangeSymbols[] = {
+                { (PRFuncPtr*) &mSymbols.fMapBufferRange, { "MapBufferRange", nullptr } },
+                { (PRFuncPtr*) &mSymbols.fFlushMappedBufferRange, { "FlushMappedBufferRange", nullptr } },
+                END_SYMBOLS
+            };
+
+            if (!LoadSymbols(mapBufferRangeSymbols, trygl, prefix)) {
+                NS_ERROR("GL supports map_buffer_range without supplying its functions.");
+
+                MarkUnsupported(GLFeature::map_buffer_range);
+                ClearSymbols(mapBufferRangeSymbols);
+            }
+        }
+
         if (IsExtensionSupported(KHR_debug)) {
             SymLoadStruct extSymbols[] = {
                 { (PRFuncPtr*) &mSymbols.fDebugMessageControl,  { "DebugMessageControl",  "DebugMessageControlKHR",  nullptr } },

gfx/gl/GLContext.h

@@ -97,6 +97,7 @@ MOZ_BEGIN_ENUM_CLASS(GLFeature)
     get_query_object_iv,
     instanced_arrays,
     instanced_non_arrays,
+    map_buffer_range,
     occlusion_query,
     occlusion_query_boolean,
     occlusion_query2,
@@ -356,6 +357,7 @@ public:
         ARB_framebuffer_sRGB,
         ARB_half_float_pixel,
         ARB_instanced_arrays,
+        ARB_map_buffer_range,
         ARB_occlusion_query2,
         ARB_pixel_buffer_object,
         ARB_robustness,
@@ -2679,6 +2681,27 @@ public:
     }
 
 
+// -----------------------------------------------------------------------------
+// Core GL & Extension ARB_map_buffer_range
+public:
+    void* fMapBufferRange(GLenum target, GLintptr offset, GLsizeiptr length,
+                          GLbitfield access)
+    {
+        ASSERT_SYMBOL_PRESENT(fMapBufferRange);
+        BEFORE_GL_CALL;
+        void* data = mSymbols.fMapBufferRange(target, offset, length, access);
+        AFTER_GL_CALL;
+        return data;
+    }
+
+    void fFlushMappedBufferRange(GLenum target, GLintptr offset, GLsizeiptr length) {
+        ASSERT_SYMBOL_PRESENT(fFlushMappedBufferRange);
+        BEFORE_GL_CALL;
+        mSymbols.fFlushMappedBufferRange(target, offset, length);
+        AFTER_GL_CALL;
+    }
+
+
 // -----------------------------------------------------------------------------
 // Constructor
 protected:

gfx/gl/GLContextFeatures.cpp

@@ -259,6 +259,15 @@ static const FeatureInfo sFeatureInfoArr[] = {
          * has no such restriction.
          */
     },
+    {
+        "map_buffer_range",
+        300, // OpenGL version
+        300, // OpenGL ES version
+        GLContext::ARB_map_buffer_range,
+        {
+            GLContext::Extensions_End
+        }
+    },
     {
         "occlusion_query",
         200, // OpenGL version

gfx/gl/GLContextSymbols.h

@@ -527,6 +527,12 @@ struct GLContextSymbols
     pfnIsFenceT fIsFence;
     typedef void (GLAPIENTRY * pfnGetFenceivT) (GLuint fence, GLenum pname, GLint* params);
     pfnGetFenceivT fGetFenceiv;
+
+    // map_buffer_range
+    typedef void* (GLAPIENTRY * PFNGLMAPBUFFERRANGEPROC) (GLenum target, GLintptr offset, GLsizeiptr length, GLbitfield access);
+    PFNGLMAPBUFFERRANGEPROC fMapBufferRange;
+    typedef void (GLAPIENTRY * PFNGLFLUSHMAPPEDBUFFERRANGEPROC) (GLenum target, GLintptr offset, GLsizeiptr length);
+    PFNGLFLUSHMAPPEDBUFFERRANGEPROC fFlushMappedBufferRange;
 };
 
 }