FBFetch refactor + arm support

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"
 #include "SkTSort.h"
 
 GrGLCaps::GrGLCaps() {
     this->reset();
 }
 
 void GrGLCaps::reset() {
     INHERITED::reset();
 
     fVerifiedColorConfigs.reset();
     fStencilFormats.reset();
     fStencilVerifiedColorConfigs.reset();
     fMSFBOType = kNone_MSFBOType;
-    fFBFetchType = kNone_FBFetchType;
     fInvalidateFBType = kNone_InvalidateFBType;
     fLATCAlias = kLATC_LATCAlias;
     fMapBufferType = kNone_MapBufferType;
     fMaxFragmentUniformVectors = 0;
     fMaxVertexAttributes = 0;
     fMaxFragmentTextureUnits = 0;
     fMaxFixedFunctionTextureCoords = 0;
     fRGBA8RenderbufferSupport = false;
     fBGRAIsInternalFormat = false;
     fTextureSwizzleSupport = false;
     fUnpackRowLengthSupport = false;
     fUnpackFlipYSupport = false;
     fPackRowLengthSupport = false;
     fPackFlipYSupport = false;
     fTextureUsageSupport = false;
     fTexStorageSupport = false;
     fTextureRedSupport = false;
     fImagingSupport = false;
     fTwoFormatLimit = false;
     fFragCoordsConventionSupport = false;
     fVertexArrayObjectSupport = false;
     fUseNonVBOVertexAndIndexDynamicData = false;
     fIsCoreProfile = false;
     fFullClearIsFree = false;
     fDropsTileOnZeroDivide = false;
+    fFBFetchSupport = false;
+    fFBFetchColorName = NULL;
+    fFBFetchExtensionString = NULL;
 }
 
 GrGLCaps::GrGLCaps(const GrGLCaps& caps) : GrDrawTargetCaps() {
     *this = caps;
 }
 
 GrGLCaps& GrGLCaps::operator= (const GrGLCaps& caps) {
     INHERITED::operator=(caps);
     fVerifiedColorConfigs = caps.fVerifiedColorConfigs;
     fStencilFormats = caps.fStencilFormats;
     fStencilVerifiedColorConfigs = caps.fStencilVerifiedColorConfigs;
     fLATCAlias = caps.fLATCAlias;
     fMaxFragmentUniformVectors = caps.fMaxFragmentUniformVectors;
     fMaxVertexAttributes = caps.fMaxVertexAttributes;
     fMaxFragmentTextureUnits = caps.fMaxFragmentTextureUnits;
     fMaxFixedFunctionTextureCoords = caps.fMaxFixedFunctionTextureCoords;
     fMSFBOType = caps.fMSFBOType;
-    fFBFetchType = caps.fFBFetchType;
     fInvalidateFBType = caps.fInvalidateFBType;
     fMapBufferType = caps.fMapBufferType;
     fRGBA8RenderbufferSupport = caps.fRGBA8RenderbufferSupport;
     fBGRAIsInternalFormat = caps.fBGRAIsInternalFormat;
     fTextureSwizzleSupport = caps.fTextureSwizzleSupport;
     fUnpackRowLengthSupport = caps.fUnpackRowLengthSupport;
     fUnpackFlipYSupport = caps.fUnpackFlipYSupport;
     fPackRowLengthSupport = caps.fPackRowLengthSupport;
     fPackFlipYSupport = caps.fPackFlipYSupport;
     fTextureUsageSupport = caps.fTextureUsageSupport;
     fTexStorageSupport = caps.fTexStorageSupport;
     fTextureRedSupport = caps.fTextureRedSupport;
     fImagingSupport = caps.fImagingSupport;
     fTwoFormatLimit = caps.fTwoFormatLimit;
     fFragCoordsConventionSupport = caps.fFragCoordsConventionSupport;
     fVertexArrayObjectSupport = caps.fVertexArrayObjectSupport;
     fUseNonVBOVertexAndIndexDynamicData = caps.fUseNonVBOVertexAndIndexDynamicData;
     fIsCoreProfile = caps.fIsCoreProfile;
     fFullClearIsFree = caps.fFullClearIsFree;
     fDropsTileOnZeroDivide = caps.fDropsTileOnZeroDivide;
+    fFBFetchSupport = caps.fFBFetchSupport;
+    fFBFetchColorName = caps.fFBFetchColorName;
+    fFBFetchExtensionString = caps.fFBFetchExtensionString;
 
     return *this;
 }
 
 bool GrGLCaps::init(const GrGLContextInfo& ctxInfo, const GrGLInterface* gli) {
 
     this->reset();
     if (!ctxInfo.isInitialized()) {
         return false;
     }
@@ skipping 127 matching lines @@
     if (kGL_GrGLStandard == standard) {
         fVertexArrayObjectSupport = version >= GR_GL_VER(3, 0) ||
                                     ctxInfo.hasExtension("GL_ARB_vertex_array_object");
     } else {
         fVertexArrayObjectSupport = version >= GR_GL_VER(3, 0) ||
                                     ctxInfo.hasExtension("GL_OES_vertex_array_object");
     }
 
     if (kGLES_GrGLStandard == standard) {
         if (ctxInfo.hasExtension("GL_EXT_shader_framebuffer_fetch")) {
-            fFBFetchType = kEXT_FBFetchType;
+            fFBFetchSupport = true;
+            fFBFetchColorName = "gl_LastFragData[0]";
+            fFBFetchExtensionString = "GL_EXT_shader_framebuffer_fetch";
         } else if (ctxInfo.hasExtension("GL_NV_shader_framebuffer_fetch")) {
-            fFBFetchType = kNV_FBFetchType;
+            fFBFetchSupport = true;
+            fFBFetchColorName = "gl_LastFragData[0]";
+            fFBFetchExtensionString = "GL_NV_shader_framebuffer_fetch";
+        } else if (ctxInfo.hasExtension("GL_ARM_shader_framebuffer_fetch")) {
+            // The arm extension requires specifically enabling MSAA fetching per sample.
+            // On some devices this may have a perf hit.  Also multiple render targets are disabled
+            GR_GL_CALL(gli, Enable(GR_GL_FETCH_PER_SAMPLE_ARM));

[bsalomon, 2014/07/31 13:45:05]

I don't think that this is the right place for this call. We don't set any other
state through the caps class. We would enable this once at startup but we are
not always the only user of the GL context. It could be disabled by other code.
It should happen in a function called when we flush the graphics state so that
it gets set again when we get a GrContext::resetContext() call (which is how our
client lets us know that someone else was messing with the GL context).

+            fFBFetchSupport = true;
+            fFBFetchColorName = "gl_LastFragColorARM";
+            fFBFetchExtensionString = "GL_ARM_shader_framebuffer_fetch";
         }
     }
 
     // Adreno GPUs have a tendency to drop tiles when there is a divide-by-zero in a shader
     fDropsTileOnZeroDivide = kQualcomm_GrGLVendor == ctxInfo.vendor();
 
     this->initFSAASupport(ctxInfo, gli);
     this->initStencilFormats(ctxInfo);
 
     /**************************************************************************
@@ skipping 79 matching lines @@
                    ctxInfo.hasExtension("GL_ARB_program_interface_query")) &&
                   NULL != gli->fFunctions.fProgramPathFragmentInputGen));
         } else {
             // Note: path rendering is not yet implemented for GLES.
             fPathRenderingSupport = ctxInfo.version() >= GR_GL_VER(3,1) && false;
         }
     }
 
     fGpuTracingSupport = ctxInfo.hasExtension("GL_EXT_debug_marker");
 
-    fDstReadInShaderSupport = kNone_FBFetchType != fFBFetchType;
+    // For now these two are equivalent but we could have dst read in shader via some other method
+    fDstReadInShaderSupport = fFBFetchSupport;
 
     // Disable scratch texture reuse on Mali and Adreno devices
     fReuseScratchTextures = kARM_GrGLVendor != ctxInfo.vendor() &&
                             kQualcomm_GrGLVendor != ctxInfo.vendor();
 
     // Enable supported shader-related caps
     if (kGL_GrGLStandard == standard) {
         fDualSourceBlendingSupport = ctxInfo.version() >= GR_GL_VER(3,3) ||
                                      ctxInfo.hasExtension("GL_ARB_blend_func_extended");
         fShaderDerivativeSupport = true;
@@ skipping 419 matching lines @@
     };
     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_3_0_MSFBOType);
     GR_STATIC_ASSERT(4 == kES_Apple_MSFBOType);
     GR_STATIC_ASSERT(5 == kES_IMG_MsToTexture_MSFBOType);
     GR_STATIC_ASSERT(6 == kES_EXT_MsToTexture_MSFBOType);
     GR_STATIC_ASSERT(SK_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(SK_ARRAY_COUNT(kFBFetchTypeStr) == kLast_FBFetchType + 1);
-
     static const char* kInvalidateFBTypeStr[] = {
         "None",
         "Discard",
         "Invalidate",
     };
     GR_STATIC_ASSERT(0 == kNone_InvalidateFBType);
     GR_STATIC_ASSERT(1 == kDiscard_InvalidateFBType);
     GR_STATIC_ASSERT(2 == kInvalidate_InvalidateFBType);
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kInvalidateFBTypeStr) == kLast_InvalidateFBType + 1);
 
     static const char* kMapBufferTypeStr[] = {
         "None",
         "MapBuffer",
         "MapBufferRange",
         "Chromium",
     };
     GR_STATIC_ASSERT(0 == kNone_MapBufferType);
     GR_STATIC_ASSERT(1 == kMapBuffer_MapBufferType);
     GR_STATIC_ASSERT(2 == kMapBufferRange_MapBufferType);
     GR_STATIC_ASSERT(3 == kChromium_MapBufferType);
     GR_STATIC_ASSERT(SK_ARRAY_COUNT(kMapBufferTypeStr) == kLast_MapBufferType + 1);
 
     r.appendf("Core Profile: %s\n", (fIsCoreProfile ? "YES" : "NO"));
     r.appendf("MSAA Type: %s\n", kMSFBOExtStr[fMSFBOType]);
-    r.appendf("FB Fetch Type: %s\n", kFBFetchTypeStr[fFBFetchType]);
+    r.appendf("FB Fetch Support: %s\n", (fFBFetchSupport ? "YES" : "NO"));
     r.appendf("Invalidate FB Type: %s\n", kInvalidateFBTypeStr[fInvalidateFBType]);
     r.appendf("Map Buffer Type: %s\n", kMapBufferTypeStr[fMapBufferType]);
     r.appendf("Max FS Uniform Vectors: %d\n", fMaxFragmentUniformVectors);
     r.appendf("Max FS Texture Units: %d\n", fMaxFragmentTextureUnits);
     if (!fIsCoreProfile) {
         r.appendf("Max Fixed Function Texture Coords: %d\n", fMaxFixedFunctionTextureCoords);
     }
     r.appendf("Max Vertex Attributes: %d\n", fMaxVertexAttributes);
     r.appendf("Support RGBA8 Render Buffer: %s\n", (fRGBA8RenderbufferSupport ? "YES": "NO"));
     r.appendf("BGRA is an internal format: %s\n", (fBGRAIsInternalFormat ? "YES": "NO"));
@@ skipping 10 matching lines @@
     r.appendf("Two Format Limit: %s\n", (fTwoFormatLimit ? "YES": "NO"));
     r.appendf("Fragment coord conventions support: %s\n",
              (fFragCoordsConventionSupport ? "YES": "NO"));
     r.appendf("Vertex array object support: %s\n", (fVertexArrayObjectSupport ? "YES": "NO"));
     r.appendf("Use non-VBO for dynamic data: %s\n",
              (fUseNonVBOVertexAndIndexDynamicData ? "YES" : "NO"));
     r.appendf("Full screen clear is free: %s\n", (fFullClearIsFree ? "YES" : "NO"));
     r.appendf("Drops tile on zero divide: %s\n", (fDropsTileOnZeroDivide ? "YES" : "NO"));
     return r;
 }