Add support for GL_*_shader_framebuffer_fetch

src/gpu/gl/GrGLCaps.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLCaps.h"
 #include "GrGLContext.h"
 #include "SkTSearch.h"
 
 SK_DEFINE_INST_COUNT(GrGLCaps)
 
 GrGLCaps::GrGLCaps() {
     this->reset();
 }
 
 void GrGLCaps::reset() {
     INHERITED::reset();
 
     fVerifiedColorConfigs.reset();
     fStencilFormats.reset();
     fStencilVerifiedColorConfigs.reset();
     fMSFBOType = kNone_MSFBOType;
     fCoverageAAType = kNone_CoverageAAType;
+    fFBFetchType = kNone_FBFetchType;
     fMaxFragmentUniformVectors = 0;
     fMaxVertexAttributes = 0;
     fRGBA8RenderbufferSupport = false;
     fBGRAFormatSupport = false;
     fBGRAIsInternalFormat = false;
     fTextureSwizzleSupport = false;
     fUnpackRowLengthSupport = false;
     fUnpackFlipYSupport = false;
     fPackRowLengthSupport = false;
     fPackFlipYSupport = false;
@@ skipping 16 matching lines @@
 GrGLCaps& GrGLCaps::operator = (const GrGLCaps& caps) {
     INHERITED::operator=(caps);
     fVerifiedColorConfigs = caps.fVerifiedColorConfigs;
     fStencilFormats = caps.fStencilFormats;
     fStencilVerifiedColorConfigs = caps.fStencilVerifiedColorConfigs;
     fMaxFragmentUniformVectors = caps.fMaxFragmentUniformVectors;
     fMaxVertexAttributes = caps.fMaxVertexAttributes;
     fMSFBOType = caps.fMSFBOType;
     fCoverageAAType = caps.fCoverageAAType;
     fMSAACoverageModes = caps.fMSAACoverageModes;
+    fFBFetchType = caps.fFBFetchType;
     fRGBA8RenderbufferSupport = caps.fRGBA8RenderbufferSupport;
     fBGRAFormatSupport = caps.fBGRAFormatSupport;
     fBGRAIsInternalFormat = caps.fBGRAIsInternalFormat;
     fTextureSwizzleSupport = caps.fTextureSwizzleSupport;
     fUnpackRowLengthSupport = caps.fUnpackRowLengthSupport;
     fUnpackFlipYSupport = caps.fUnpackFlipYSupport;
     fPackRowLengthSupport = caps.fPackRowLengthSupport;
     fPackFlipYSupport = caps.fPackFlipYSupport;
     fTextureUsageSupport = caps.fTextureUsageSupport;
     fTexStorageSupport = caps.fTexStorageSupport;
@@ skipping 125 matching lines @@
 
     fDiscardFBSupport = ctxInfo.hasExtension("GL_EXT_discard_framebuffer");
 
     if (kDesktop_GrGLBinding == binding) {
         fVertexArrayObjectSupport = version >= GR_GL_VER(3, 0) ||
                                     ctxInfo.hasExtension("GL_ARB_vertex_array_object");
     } else {
         fVertexArrayObjectSupport = ctxInfo.hasExtension("GL_OES_vertex_array_object");
     }
 
+    if (kES2_GrGLBinding == binding) {
+        if (ctxInfo.hasExtension("GL_EXT_shader_framebuffer_fetch")) {
+            fFBFetchType = kEXT_FBFetchType;
+        } else if (ctxInfo.hasExtension("GL_NV_shader_framebuffer_fetch")) {
+            fFBFetchType = kNV_FBFetchType;
+        }
+    }
+
     this->initFSAASupport(ctxInfo, gli);
     this->initStencilFormats(ctxInfo);
 
     /**************************************************************************
      * GrDrawTargetCaps fields
      **************************************************************************/
     GrGLint maxTextureUnits;
     // check FS and fixed-function texture unit limits
     // we only use textures in the fragment stage currently.
     // checks are > to make sure we have a spare unit.
@@ skipping 49 matching lines @@
 
     GR_GL_GetIntegerv(gli, GR_GL_MAX_TEXTURE_SIZE, &fMaxTextureSize);
     GR_GL_GetIntegerv(gli, GR_GL_MAX_RENDERBUFFER_SIZE, &fMaxRenderTargetSize);
     // Our render targets are always created with textures as the color
     // attachment, hence this min:
     fMaxRenderTargetSize = GrMin(fMaxTextureSize, fMaxRenderTargetSize);
 
     fPathStencilingSupport = GR_GL_USE_NV_PATH_RENDERING &&
                              ctxInfo.hasExtension("GL_NV_path_rendering");
 
+    fDstReadInShaderSupport = kNone_FBFetchType != fFBFetchType;
+
     // Enable supported shader-related caps
     if (kDesktop_GrGLBinding == binding) {
         fDualSourceBlendingSupport = ctxInfo.version() >= GR_GL_VER(3,3) ||
                                      ctxInfo.hasExtension("GL_ARB_blend_func_extended");
         fShaderDerivativeSupport = true;
         // we don't support GL_ARB_geometry_shader4, just GL 3.2+ GS
         fGeometryShaderSupport = ctxInfo.version() >= GR_GL_VER(3,2) &&
                                  ctxInfo.glslGeneration() >= k150_GrGLSLGeneration;
     } else {
         fShaderDerivativeSupport = ctxInfo.hasExtension("GL_OES_standard_derivatives");
@@ skipping 227 matching lines @@
     INHERITED::print();
 
     GrPrintf("--- GL-Specific ---\n");
     for (int i = 0; i < fStencilFormats.count(); ++i) {
         GrPrintf("Stencil Format %d, stencil bits: %02d, total bits: %02d\n",
                  i,
                  fStencilFormats[i].fStencilBits,
                  fStencilFormats[i].fTotalBits);
     }
 
-    GR_STATIC_ASSERT(0 == kNone_MSFBOType);
-    GR_STATIC_ASSERT(1 == kDesktop_ARB_MSFBOType);
-    GR_STATIC_ASSERT(2 == kDesktop_EXT_MSFBOType);
-    GR_STATIC_ASSERT(3 == kES_Apple_MSFBOType);
-    GR_STATIC_ASSERT(4 == kES_IMG_MsToTexture_MSFBOType);
-    GR_STATIC_ASSERT(5 == kES_EXT_MsToTexture_MSFBOType);
-    static const char* gMSFBOExtStr[] = {
+    static const char* kMSFBOExtStr[] = {
         "None",
         "ARB",
         "EXT",
         "Apple",
         "IMG MS To Texture",
         "EXT MS To Texture",
     };
-    GrPrintf("MSAA Type: %s\n", gMSFBOExtStr[fMSFBOType]);
+    GR_STATIC_ASSERT(0 == kNone_MSFBOType);
+    GR_STATIC_ASSERT(1 == kDesktop_ARB_MSFBOType);
+    GR_STATIC_ASSERT(2 == kDesktop_EXT_MSFBOType);
+    GR_STATIC_ASSERT(3 == kES_Apple_MSFBOType);
+    GR_STATIC_ASSERT(4 == kES_IMG_MsToTexture_MSFBOType);
+    GR_STATIC_ASSERT(5 == kES_EXT_MsToTexture_MSFBOType);
+    GR_STATIC_ASSERT(GR_ARRAY_COUNT(kMSFBOExtStr) == kLast_MSFBOType + 1);
+
+    static const char* kFBFetchTypeStr[] = {
+        "None",
+        "EXT",
+        "NV",
+    };
+    GR_STATIC_ASSERT(0 == kNone_FBFetchType);
+    GR_STATIC_ASSERT(1 == kEXT_FBFetchType);
+    GR_STATIC_ASSERT(2 == kNV_FBFetchType);
+    GR_STATIC_ASSERT(GR_ARRAY_COUNT(kFBFetchTypeStr) == kLast_FBFetchType + 1);
+
+
+    GrPrintf("MSAA Type: %s\n", kMSFBOExtStr[fMSFBOType]);
+    GrPrintf("FB Fetch Type: %s\n", kFBFetchTypeStr[fFBFetchType]);
     GrPrintf("Max FS Uniform Vectors: %d\n", fMaxFragmentUniformVectors);
     GrPrintf("Max Vertex Attributes: %d\n", fMaxVertexAttributes);
     GrPrintf("Support RGBA8 Render Buffer: %s\n", (fRGBA8RenderbufferSupport ? "YES": "NO"));
     GrPrintf("BGRA support: %s\n", (fBGRAFormatSupport ? "YES": "NO"));
     GrPrintf("BGRA is an internal format: %s\n", (fBGRAIsInternalFormat ? "YES": "NO"));
     GrPrintf("Support texture swizzle: %s\n", (fTextureSwizzleSupport ? "YES": "NO"));
     GrPrintf("Unpack Row length support: %s\n", (fUnpackRowLengthSupport ? "YES": "NO"));
     GrPrintf("Unpack Flip Y support: %s\n", (fUnpackFlipYSupport ? "YES": "NO"));
     GrPrintf("Pack Row length support: %s\n", (fPackRowLengthSupport ? "YES": "NO"));
     GrPrintf("Pack Flip Y support: %s\n", (fPackFlipYSupport ? "YES": "NO"));
 
     GrPrintf("Texture Usage support: %s\n", (fTextureUsageSupport ? "YES": "NO"));
     GrPrintf("Texture Storage support: %s\n", (fTexStorageSupport ? "YES": "NO"));
     GrPrintf("GL_R support: %s\n", (fTextureRedSupport ? "YES": "NO"));
     GrPrintf("GL_ARB_imaging support: %s\n", (fImagingSupport ? "YES": "NO"));
     GrPrintf("Two Format Limit: %s\n", (fTwoFormatLimit ? "YES": "NO"));
     GrPrintf("Fragment coord conventions support: %s\n",
              (fFragCoordsConventionSupport ? "YES": "NO"));
     GrPrintf("Vertex array object support: %s\n", (fVertexArrayObjectSupport ? "YES": "NO"));
     GrPrintf("Use non-VBO for dynamic data: %s\n",
              (fUseNonVBOVertexAndIndexDynamicData ? "YES" : "NO"));
     GrPrintf("Core Profile: %s\n", (fIsCoreProfile ? "YES" : "NO"));
     GrPrintf("Discard FrameBuffer support: %s\n", (fDiscardFBSupport ? "YES" : "NO"));
 }