Implement texel buffers

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 1364 matching lines @@
                                kQualcomm_GrGLVendor != ctxInfo.vendor()) &&
                                ctxInfo.hasExtension("GL_EXT_texture_storage");
     }
 
     // TODO: remove after command buffer supports full ES 3.0
     if (kGLES_GrGLStandard == standard && version >= GR_GL_VER(3,0) &&
         kChromium_GrGLDriver == ctxInfo.driver()) {
         texStorageSupported = false;
     }
 
+    bool texelBufferSupport = this->shaderCaps()->texelBufferSupport();
+
     fConfigTable[kUnknown_GrPixelConfig].fFormats.fBaseInternalFormat = 0;
     fConfigTable[kUnknown_GrPixelConfig].fFormats.fSizedInternalFormat = 0;
     fConfigTable[kUnknown_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage] = 0;
     fConfigTable[kUnknown_GrPixelConfig].fFormats.fExternalType = 0;
     fConfigTable[kUnknown_GrPixelConfig].fFormatType = kNormalizedFixedPoint_FormatType;
     fConfigTable[kUnknown_GrPixelConfig].fSwizzle = GrSwizzle::RGBA();
 
     fConfigTable[kRGBA_8888_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_RGBA;
     fConfigTable[kRGBA_8888_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_RGBA8;
     fConfigTable[kRGBA_8888_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage] =
         GR_GL_RGBA;
     fConfigTable[kRGBA_8888_GrPixelConfig].fFormats.fExternalType = GR_GL_UNSIGNED_BYTE;
     fConfigTable[kRGBA_8888_GrPixelConfig].fFormatType = kNormalizedFixedPoint_FormatType;
     fConfigTable[kRGBA_8888_GrPixelConfig].fFlags = ConfigInfo::kTextureable_Flag;
     if (kGL_GrGLStandard == standard) {
         // We require some form of FBO support and all GLs with FBO support can render to RGBA8
         fConfigTable[kRGBA_8888_GrPixelConfig].fFlags |= allRenderFlags;
     } else {
         if (version >= GR_GL_VER(3,0) || ctxInfo.hasExtension("GL_OES_rgb8_rgba8") ||
             ctxInfo.hasExtension("GL_ARM_rgba8")) {
             fConfigTable[kRGBA_8888_GrPixelConfig].fFlags |= allRenderFlags;
         }
     }
     if (texStorageSupported) {
         fConfigTable[kRGBA_8888_GrPixelConfig].fFlags |= ConfigInfo::kCanUseTexStorage_Flag;
     }
+    if (texelBufferSupport) {
+        fConfigTable[kRGBA_8888_GrPixelConfig].fFlags |= ConfigInfo::kCanUseWithTexelBuffer_Flag;
+    }
     fConfigTable[kRGBA_8888_GrPixelConfig].fSwizzle = GrSwizzle::RGBA();
 
     fConfigTable[kBGRA_8888_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage] =
         GR_GL_BGRA;
     fConfigTable[kBGRA_8888_GrPixelConfig].fFormats.fExternalType  = GR_GL_UNSIGNED_BYTE;
     fConfigTable[kBGRA_8888_GrPixelConfig].fFormatType = kNormalizedFixedPoint_FormatType;
     if (kGL_GrGLStandard == standard) {
         fConfigTable[kBGRA_8888_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_RGBA;
         fConfigTable[kBGRA_8888_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_RGBA8;
         if (version >= GR_GL_VER(1, 2) || ctxInfo.hasExtension("GL_EXT_bgra")) {
@@ skipping 139 matching lines @@
         fConfigTable[kRGBA_4444_GrPixelConfig].fFlags |= ConfigInfo::kCanUseTexStorage_Flag;
     }
     fConfigTable[kRGBA_4444_GrPixelConfig].fSwizzle = GrSwizzle::RGBA();
 
     if (this->textureRedSupport()) {
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_RED;
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_R8;
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage] =
             GR_GL_RED;
         fConfigTable[kAlpha_8_GrPixelConfig].fSwizzle = GrSwizzle::RRRR();
+        if (texelBufferSupport) {
+            fConfigTable[kAlpha_8_GrPixelConfig].fFlags |= ConfigInfo::kCanUseWithTexelBuffer_Flag;
+        }
     } else {
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_ALPHA;
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_ALPHA8;
         fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage] =
             GR_GL_ALPHA;
         fConfigTable[kAlpha_8_GrPixelConfig].fSwizzle = GrSwizzle::AAAA();
     }
     fConfigTable[kAlpha_8_GrPixelConfig].fFormats.fExternalType = GR_GL_UNSIGNED_BYTE;
     fConfigTable[kAlpha_8_GrPixelConfig].fFormatType = kNormalizedFixedPoint_FormatType;
     fConfigTable[kAlpha_8_GrPixelConfig].fFlags = ConfigInfo::kTextureable_Flag;
@@ skipping 48 matching lines @@
         // For now we only enable rendering to float on desktop, because on ES we'd have to solve
         // many precision issues and no clients actually want this yet.
         if (kGL_GrGLStandard == standard /* || version >= GR_GL_VER(3,2) ||
             ctxInfo.hasExtension("GL_EXT_color_buffer_float")*/) {
             fConfigTable[kRGBA_float_GrPixelConfig].fFlags |= fpRenderFlags;
         }
     }
     if (texStorageSupported) {
         fConfigTable[kRGBA_float_GrPixelConfig].fFlags |= ConfigInfo::kCanUseTexStorage_Flag;
     }
+    if (texelBufferSupport) {
+        fConfigTable[kRGBA_float_GrPixelConfig].fFlags |= ConfigInfo::kCanUseWithTexelBuffer_Flag;
+    }
     fConfigTable[kRGBA_float_GrPixelConfig].fSwizzle = GrSwizzle::RGBA();
 
     if (this->textureRedSupport()) {
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_RED;
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_R16F;
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage]
             = GR_GL_RED;
         fConfigTable[kAlpha_half_GrPixelConfig].fSwizzle = GrSwizzle::RRRR();
+        if (texelBufferSupport) {
+            fConfigTable[kAlpha_half_GrPixelConfig].fFlags |=
+                ConfigInfo::kCanUseWithTexelBuffer_Flag;
+        }
     } else {
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fBaseInternalFormat = GR_GL_ALPHA;
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fSizedInternalFormat = GR_GL_ALPHA16F;
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fExternalFormat[kOther_ExternalFormatUsage]
             = GR_GL_ALPHA;
         fConfigTable[kAlpha_half_GrPixelConfig].fSwizzle = GrSwizzle::AAAA();
     }
     if (kGL_GrGLStandard == ctxInfo.standard() || ctxInfo.version() >= GR_GL_VER(3, 0)) {
         fConfigTable[kAlpha_half_GrPixelConfig].fFormats.fExternalType = GR_GL_HALF_FLOAT;
     } else {
@@ skipping 28 matching lines @@
         fConfigTable[kRGBA_half_GrPixelConfig].fFlags = ConfigInfo::kTextureable_Flag;
         // ES requires 3.2 or EXT_color_buffer_half_float.
         if (kGL_GrGLStandard == standard || version >= GR_GL_VER(3,2) ||
              ctxInfo.hasExtension("GL_EXT_color_buffer_half_float")) {
             fConfigTable[kRGBA_half_GrPixelConfig].fFlags |= fpRenderFlags;
         }
     }
     if (texStorageSupported) {
         fConfigTable[kRGBA_half_GrPixelConfig].fFlags |= ConfigInfo::kCanUseTexStorage_Flag;
     }
+    if (texelBufferSupport) {
+        fConfigTable[kRGBA_half_GrPixelConfig].fFlags |= ConfigInfo::kCanUseWithTexelBuffer_Flag;
+    }
     fConfigTable[kRGBA_half_GrPixelConfig].fSwizzle = GrSwizzle::RGBA();
 
     // Compressed texture support
 
     // glCompressedTexImage2D is available on all OpenGL ES devices. It is available on standard
     // OpenGL after version 1.3. We'll assume at least that level of OpenGL support.
 
     // TODO: Fix command buffer bindings and remove this.
     fCompressedTexSubImageSupport = SkToBool(gli->fFunctions.fCompressedTexSubImage2D);
 
@@ skipping 180 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) {}