Add support for glMapBufferRange. Use glMapBufferRange and glMapBufferSubData.

src/gpu/gl/GrGLCaps.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef GrGLCaps_DEFINED
 #define GrGLCaps_DEFINED
@@ skipping 68 matching lines @@
     };
 
     enum InvalidateFBType {
         kNone_InvalidateFBType,
         kDiscard_InvalidateFBType,       //<! glDiscardFramebuffer()
         kInvalidate_InvalidateFBType,     //<! glInvalidateFramebuffer()
 
         kLast_InvalidateFBType = kInvalidate_InvalidateFBType
     };
 
+    enum MapBufferType {
+        kNone_MapBufferType,
+        kMapBuffer_MapBufferType,         // glMapBuffer()
+        kMapBufferRange_MapBufferType,    // glMapBufferRange()
+        kChromium_MapBufferType,          // GL_CHROMIUM_map_sub
+
+        kLast_MapBufferType = kChromium_MapBufferType,
+    };
+
     /**
      * Creates a GrGLCaps that advertises no support for any extensions,
      * formats, etc. Call init to initialize from a GrGLContextInfo.
      */
     GrGLCaps();
 
     GrGLCaps(const GrGLCaps& caps);
 
     GrGLCaps& operator = (const GrGLCaps& caps);
 
@@ skipping 63 matching lines @@
      */
     bool usesImplicitMSAAResolve() const {
         return kES_IMG_MsToTexture_MSFBOType == fMSFBOType ||
                kES_EXT_MsToTexture_MSFBOType == fMSFBOType;
     }
 
     FBFetchType fbFetchType() const { return fFBFetchType; }
 
     InvalidateFBType invalidateFBType() const { return fInvalidateFBType; }
 
-    /**
-     * Returs a string containeng the caps info.
-     */
-    virtual SkString dump() const SK_OVERRIDE;
+    /// What type of buffer mapping is supported?
+    MapBufferType mapBufferType() const { return fMapBufferType; }
 
     /**
      * Gets an array of legal stencil formats. These formats are not guaranteed
      * to be supported by the driver but are legal GLenum names given the GL
      * version and extensions supported.
      */
     const SkTArray<StencilFormat, true>& stencilFormats() const {
         return fStencilFormats;
     }
 
@@ skipping 65 matching lines @@
                              GrGLenum format,
                              GrGLenum type) const;
 
     bool isCoreProfile() const { return fIsCoreProfile; }
 
 
     bool fullClearIsFree() const { return fFullClearIsFree; }
 
     bool dropsTileOnZeroDivide() const { return fDropsTileOnZeroDivide; }
 
-    /// Is GL_CHROMIUM_map_sub supported?
-    bool mapSubSupport() const { return fMapSubSupport; }
+    /**
+     * Returns a string containing the caps info.
+     */
+    virtual SkString dump() const SK_OVERRIDE;
 
 private:
     /**
      * Maintains a bit per GrPixelConfig. It is used to avoid redundantly
      * performing glCheckFrameBufferStatus for the same config.
      */
     struct VerifiedColorConfigs {
         VerifiedColorConfigs() {
             this->reset();
         }
@@ skipping 42 matching lines @@
     SkTArray<VerifiedColorConfigs, true> fStencilVerifiedColorConfigs;
 
     int fMaxFragmentUniformVectors;
     int fMaxVertexAttributes;
     int fMaxFragmentTextureUnits;
     int fMaxFixedFunctionTextureCoords;
 
     MSFBOType           fMSFBOType;
     FBFetchType         fFBFetchType;
     InvalidateFBType    fInvalidateFBType;
+    MapBufferType       fMapBufferType;
 
     bool fRGBA8RenderbufferSupport : 1;
     bool fBGRAFormatSupport : 1;
     bool fBGRAIsInternalFormat : 1;
     bool fTextureSwizzleSupport : 1;
     bool fUnpackRowLengthSupport : 1;
     bool fUnpackFlipYSupport : 1;
     bool fPackRowLengthSupport : 1;
     bool fPackFlipYSupport : 1;
     bool fTextureUsageSupport : 1;
     bool fTexStorageSupport : 1;
     bool fTextureRedSupport : 1;
     bool fImagingSupport  : 1;
     bool fTwoFormatLimit : 1;
     bool fFragCoordsConventionSupport : 1;
     bool fVertexArrayObjectSupport : 1;
     bool fUseNonVBOVertexAndIndexDynamicData : 1;
     bool fIsCoreProfile : 1;
     bool fFullClearIsFree : 1;
     bool fDropsTileOnZeroDivide : 1;
-    bool fMapSubSupport : 1;
 
     typedef GrDrawTargetCaps INHERITED;
 };
 
 #endif