Add GLSL support for texelFetch

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"
 
@@ skipping 718 matching lines @@
 
     if (glslCaps->fExternalTextureSupport) {
         if (ctxInfo.glslGeneration() == k110_GrGLSLGeneration) {
             glslCaps->fExternalTextureExtensionString = "GL_OES_EGL_image_external";
         } else {
             glslCaps->fExternalTextureExtensionString = "GL_OES_EGL_image_external_essl3";
         }
     }
 
     if (kGL_GrGLStandard == standard) {
-        glslCaps->fBufferTextureSupport = ctxInfo.version() > GR_GL_VER(3, 1) &&
-                                          ctxInfo.glslGeneration() >= k330_GrGLSLGeneration;
+        glslCaps->fTexelFetchSupport = ctxInfo.glslGeneration() >= k130_GrGLSLGeneration;
     } else {
-        if (ctxInfo.version() > GR_GL_VER(3, 2) &&
-            ctxInfo.glslGeneration() >= k320es_GrGLSLGeneration) {
-            glslCaps->fBufferTextureSupport = true;
-        } else if (ctxInfo.hasExtension("GL_OES_texture_buffer")) {
-            glslCaps->fBufferTextureSupport = true;
-            glslCaps->fBufferTextureExtensionString = "GL_OES_texture_buffer";
-        } else if (ctxInfo.hasExtension("GL_EXT_texture_buffer")) {
-            glslCaps->fBufferTextureSupport = true;
-            glslCaps->fBufferTextureExtensionString = "GL_EXT_texture_buffer";
+        glslCaps->fTexelFetchSupport =
+            ctxInfo.glslGeneration() >= k330_GrGLSLGeneration; // We use this value for GLSL ES 3.0.
+    }
+
+    if (glslCaps->fTexelFetchSupport) {
+        if (kGL_GrGLStandard == standard) {
+            glslCaps->fTexelBufferSupport = ctxInfo.version() >= GR_GL_VER(4, 3) &&
+                                            ctxInfo.glslGeneration() >= k330_GrGLSLGeneration;
+        } else {
+            if (ctxInfo.version() >= GR_GL_VER(3, 2) &&
+                ctxInfo.glslGeneration() >= k320es_GrGLSLGeneration) {
+                glslCaps->fTexelBufferSupport = true;
+            } else if (ctxInfo.hasExtension("GL_OES_texture_buffer")) {
+                glslCaps->fTexelBufferSupport = true;
+                glslCaps->fTexelBufferExtensionString = "GL_OES_texture_buffer";
+            } else if (ctxInfo.hasExtension("GL_EXT_texture_buffer")) {
+                glslCaps->fTexelBufferSupport = true;
+                glslCaps->fTexelBufferExtensionString = "GL_EXT_texture_buffer";
+            }
         }
     }
 
     // The Tegra3 compiler will sometimes never return if we have min(abs(x), 1.0), so we must do
     // the abs first in a separate expression.
     if (kTegra3_GrGLRenderer == ctxInfo.renderer()) {
         glslCaps->fCanUseMinAndAbsTogether = false;
     }
 
     // On Intel GPU there is an issue where it reads the second argument to atan "- %s.x" as an int
@@ skipping 1114 matching lines @@
         for (int j = 0; j < kExternalFormatUsageCnt; ++j) {
             SkASSERT(defaultEntry.fFormats.fExternalFormat[j] !=
                      fConfigTable[i].fFormats.fExternalFormat[j]);
         }
         SkASSERT(defaultEntry.fFormats.fExternalType != fConfigTable[i].fFormats.fExternalType);
     }
 #endif
 }
 
 void GrGLCaps::onApplyOptionsOverrides(const GrContextOptions& options) {}