1 files changed, 75 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/gpu/effects/GrConfigConversionEffect.h b/gfx/skia/skia/src/gpu/effects/GrConfigConversionEffect.h
new file mode 100644
index 000000000..93b49aa65
--- /dev/null
+++ b/gfx/skia/skia/src/gpu/effects/GrConfigConversionEffect.h
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2012 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrConfigConversionEffect_DEFINED
+#define GrConfigConversionEffect_DEFINED
+
+#include "GrSingleTextureEffect.h"
+#include "GrSwizzle.h"
+
+class GrInvariantOutput;
+
+/**
+ * This class is used to perform config conversions. Clients may want to read/write data that is
+ * unpremultiplied. Additionally, the channels may also be swizzled for optimal readback/upload
+ * performance.
+ */
+class GrConfigConversionEffect : public GrSingleTextureEffect {
+public:
+    /**
+     * The PM->UPM or UPM->PM conversions to apply.
+     */
+    enum PMConversion {
+        kNone_PMConversion = 0,
+        kMulByAlpha_RoundUp_PMConversion,
+        kMulByAlpha_RoundDown_PMConversion,
+        kDivByAlpha_RoundUp_PMConversion,
+        kDivByAlpha_RoundDown_PMConversion,
+
+        kPMConversionCnt
+    };
+
+    static sk_sp<GrFragmentProcessor> Make(GrTexture*, const GrSwizzle&, PMConversion,
+                                           const SkMatrix&);
+
+    const char* name() const override { return "Config Conversion"; }
+
+    const GrSwizzle& swizzle() const { return fSwizzle; }
+    PMConversion  pmConversion() const { return fPMConversion; }
+
+    // This function determines whether it is possible to choose PM->UPM and UPM->PM conversions
+    // for which in any PM->UPM->PM->UPM sequence the two UPM values are the same. This means that
+    // if pixels are read back to a UPM buffer, written back to PM to the GPU, and read back again
+    // both reads will produce the same result. This test is quite expensive and should not be run
+    // multiple times for a given context.
+    static void TestForPreservingPMConversions(GrContext* context,
+                                               PMConversion* PMToUPMRule,
+                                               PMConversion* UPMToPMRule);
+
+private:
+    GrConfigConversionEffect(GrTexture*,
+                             const GrSwizzle&,
+                             PMConversion pmConversion,
+                             const SkMatrix& matrix);
+
+    GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
+
+    void onGetGLSLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
+
+    bool onIsEqual(const GrFragmentProcessor&) const override;
+
+    void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
+
+    GrSwizzle       fSwizzle;
+    PMConversion    fPMConversion;
+
+    GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
+
+    typedef GrSingleTextureEffect INHERITED;
+};
+
+#endif