diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/gpu/gl/GrGLCaps.cpp | 28 | ||||
-rw-r--r-- | src/gpu/gl/GrGLGpu.cpp | 42 |
2 files changed, 63 insertions, 7 deletions
diff --git a/src/gpu/gl/GrGLCaps.cpp b/src/gpu/gl/GrGLCaps.cpp index 678c62abb8..0c2ed73d7c 100644 --- a/src/gpu/gl/GrGLCaps.cpp +++ b/src/gpu/gl/GrGLCaps.cpp @@ -637,7 +637,22 @@ bool GrGLCaps::readPixelsSupported(const GrGLInterface* intf, } if (kGL_GrGLStandard == intf->fStandard) { - // All of our renderable configs can be converted to each other by glReadPixels in OpenGL. + // Some OpenGL implementations allow GL_ALPHA as a format to glReadPixels. However, + // the manual (https://www.opengl.org/sdk/docs/man/) says only these formats are allowed: + // GL_STENCIL_INDEX, GL_DEPTH_COMPONENT, GL_DEPTH_STENCIL, GL_RED, GL_GREEN, GL_BLUE, + // GL_RGB, GL_BGR, GL_RGBA, and GL_BGRA. We check for the subset that we would use. + if (readFormat != GR_GL_RED && readFormat != GR_GL_RGB && readFormat != GR_GL_RGBA && + readFormat != GR_GL_BGRA) { + return false; + } + // There is also a set of allowed types, but all the types we use are in the set: + // GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT, GL_SHORT, GL_UNSIGNED_INT, GL_INT, + // GL_HALF_FLOAT, GL_FLOAT, GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, + // GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, GL_UNSIGNED_SHORT_4_4_4_4, + // GL_UNSIGNED_SHORT_4_4_4_4_REV, GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV, + // GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,GL_UNSIGNED_INT_10_10_10_2, + // GL_UNSIGNED_INT_2_10_10_10_REV, GL_UNSIGNED_INT_24_8, GL_UNSIGNED_INT_10F_11F_11F_REV, + // GL_UNSIGNED_INT_5_9_9_9_REV, or GL_FLOAT_32_UNSIGNED_INT_24_8_REV. return true; } @@ -1051,6 +1066,17 @@ bool GrGLCaps::getExternalFormat(GrPixelConfig surfaceConfig, GrPixelConfig memo *externalFormat = fConfigTable[memoryConfig].fFormats.fExternalFormat[usage]; *externalType = fConfigTable[memoryConfig].fFormats.fExternalType; + // When GL_RED is supported as a texture format, our alpha-only textures are stored using + // GL_RED and we swizzle in order to map all components to 'r'. However, in this case the + // surface is not alpha-only and we want alpha to really mean the alpha component of the + // texture, not the red component. + if (memoryIsAlphaOnly && !surfaceIsAlphaOnly) { + if (this->textureRedSupport()) { + SkASSERT(GR_GL_RED == *externalFormat); + *externalFormat = GR_GL_ALPHA; + } + } + return true; } diff --git a/src/gpu/gl/GrGLGpu.cpp b/src/gpu/gl/GrGLGpu.cpp index 8033ea60e5..972049aa56 100644 --- a/src/gpu/gl/GrGLGpu.cpp +++ b/src/gpu/gl/GrGLGpu.cpp @@ -1951,7 +1951,8 @@ bool GrGLGpu::onGetReadPixelsInfo(GrSurface* srcSurface, int width, int height, ReadPixelTempDrawInfo* tempDrawInfo) { // This subclass can only read pixels from a render target. We could use glTexSubImage2D on // GL versions that support it but we don't today. - if (!srcSurface->asRenderTarget()) { + GrRenderTarget* srcAsRT = srcSurface->asRenderTarget(); + if (!srcAsRT) { ElevateDrawPreference(drawPreference, kRequireDraw_DrawPreference); } @@ -1992,13 +1993,20 @@ bool GrGLGpu::onGetReadPixelsInfo(GrSurface* srcSurface, int width, int height, tempDrawInfo->fTempSurfaceDesc.fConfig = kRGBA_8888_GrPixelConfig; tempDrawInfo->fSwapRAndB = true; ElevateDrawPreference(drawPreference, kRequireDraw_DrawPreference); + } else if (kRequireDraw_DrawPreference == *drawPreference && + readConfig == kAlpha_8_GrPixelConfig && + !this->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) { + // On some GLs there is no renderable single channel format. In that case we fall back + // to rendering to a RGBA and then will extract the alpha from that. + if (this->caps()->isConfigRenderable(kRGBA_8888_GrPixelConfig, false)) { + tempDrawInfo->fTempSurfaceDesc.fConfig = kRGBA_8888_GrPixelConfig; + } else { + return false; + } } - GrRenderTarget* srcAsRT = srcSurface->asRenderTarget(); - if (!srcAsRT) { - ElevateDrawPreference(drawPreference, kRequireDraw_DrawPreference); - } else if (read_pixels_pays_for_y_flip(srcAsRT, this->glCaps(), width, height, readConfig, - rowBytes)) { + if (srcAsRT && read_pixels_pays_for_y_flip(srcAsRT, this->glCaps(), width, height, readConfig, + rowBytes)) { ElevateDrawPreference(drawPreference, kGpuPrefersDraw_DrawPreference); } @@ -2049,6 +2057,28 @@ bool GrGLGpu::onReadPixels(GrSurface* surface, SkFAIL("Unknown resolve type"); } + // We have a special case fallback for reading alpha from a RGBA/BGRA surface. We will read + // back all the channels as RGBA and then extract A. + // This must be called after the RT is bound as the FBO above. + if (!this->glCaps().readPixelsSupported(this->glInterface(), config, tgt->config())) { + if ((tgt->config() == kRGBA_8888_GrPixelConfig || + tgt->config() == kBGRA_8888_GrPixelConfig) && + kAlpha_8_GrPixelConfig == config) { + SkAutoTDeleteArray<uint32_t> temp(new uint32_t[width * height * 4]); + if (this->onReadPixels(surface, left, top, width, height, kRGBA_8888_GrPixelConfig, + temp.get(), width*4)) { + uint8_t* dst = reinterpret_cast<uint8_t*>(buffer); + for (int j = 0; j < height; ++j) { + for (int i = 0; i < width; ++i) { + dst[j*rowBytes + i] = (0xFF000000U & temp[j*width+i]) >> 24; + } + } + return true; + } + } + return false; + } + const GrGLIRect& glvp = tgt->getViewport(); // the read rect is viewport-relative |