diff options
| -rw-r--r-- | include/gpu/GrContext.h | 13 | ||||
| -rw-r--r-- | src/gpu/GrContext.cpp | 17 |
2 files changed, 30 insertions, 0 deletions
diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h index ad3789b1a8..1834586578 100644 --- a/include/gpu/GrContext.h +++ b/include/gpu/GrContext.h @@ -306,6 +306,19 @@ public: */ int getMaxSampleCount() const; + /** + * Returns the recommended sample count for a render target when using this + * context. + * + * @param config the configuration of the render target. + * @param dpi the display density in dots per inch. + * + * @return sample count that should be perform well and have good enough + * rendering quality for the display. Alternatively returns 0 if + * MSAA is not supported or recommended to be used by default. + */ + int getRecommendedSampleCount(GrPixelConfig config, SkScalar dpi) const; + /////////////////////////////////////////////////////////////////////////// // Backend Surfaces diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp index bb0f4fa9fa..c7e3433938 100644 --- a/src/gpu/GrContext.cpp +++ b/src/gpu/GrContext.cpp @@ -1703,6 +1703,23 @@ bool GrContext::isConfigRenderable(GrPixelConfig config, bool withMSAA) const { return fGpu->caps()->isConfigRenderable(config, withMSAA); } +int GrContext::getRecommendedSampleCount(GrPixelConfig config, + SkScalar dpi) const { + if (!this->isConfigRenderable(config, true)) { + return 0; + } + int chosenSampleCount = 0; + if (fGpu->caps()->pathRenderingSupport()) { + if (dpi >= 250.0f) { + chosenSampleCount = 4; + } else { + chosenSampleCount = 16; + } + } + return chosenSampleCount <= fGpu->caps()->maxSampleCount() ? + chosenSampleCount : 0; +} + void GrContext::setupDrawBuffer() { SkASSERT(NULL == fDrawBuffer); SkASSERT(NULL == fDrawBufferVBAllocPool); |