add srgb gamma colorfilters
... faster and more accurate than using SkTableColorFilter
todo: update blink after this lands
Bug:737981
Change-Id: I55b5c60dd23b9d2cbe9d60f83c74be1a8f3dcfcf
Reviewed-on: https://skia-review.googlesource.com/21368
Commit-Queue: Mike Reed <reed@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/include/core/SkColorFilter.h b/include/core/SkColorFilter.h
index 1033a72..68142a2 100644
--- a/include/core/SkColorFilter.h
+++ b/include/core/SkColorFilter.h
@@ -113,6 +113,14 @@
*/
static sk_sp<SkColorFilter> MakeMatrixFilterRowMajor255(const SkScalar array[20]);
+ /** Construct a colorfilter that applies the srgb gamma curve to the RGB channels */
+ static sk_sp<SkColorFilter> MakeLinearToSRGBGamma();
+
+ /** Construct a colorfilter that applies the inverse of the srgb gamma curve to the
+ * RGB channels
+ */
+ static sk_sp<SkColorFilter> MakeSRGBToLinearGamma();
+
#if SK_SUPPORT_GPU
/**
* A subclass may implement this factory function to work with the GPU backend. It returns
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index dde939b..1676fc3 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -370,7 +370,7 @@
SkPaint gammaPaint;
gammaPaint.setBlendMode(SkBlendMode::kSrc);
if (doGamma) {
- gammaPaint.setColorFilter(sk_tool_utils::MakeLinearToSRGBColorFilter());
+ gammaPaint.setColorFilter(SkColorFilter::MakeLinearToSRGBGamma());
}
gpuCanvas->drawImage(offscreenImage, 0, 0, &gammaPaint);
diff --git a/src/core/SkColorFilter.cpp b/src/core/SkColorFilter.cpp
index a107a06..3da812a 100644
--- a/src/core/SkColorFilter.cpp
+++ b/src/core/SkColorFilter.cpp
@@ -174,8 +174,6 @@
return MakeComposeFilter(std::move(outer), std::move(inner));
}
-///////////////////////////////////////////////////////////////////////////////////////////////////
-
sk_sp<SkColorFilter> SkColorFilter::MakeComposeFilter(sk_sp<SkColorFilter> outer,
sk_sp<SkColorFilter> inner) {
if (!outer) {
@@ -198,9 +196,91 @@
return sk_sp<SkColorFilter>(new SkComposeColorFilter(std::move(outer), std::move(inner),count));
}
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#if SK_SUPPORT_GPU
+#include "../gpu/effects/GrSRGBEffect.h"
+#endif
+
+class SkSRGBGammaColorFilter : public SkColorFilter {
+public:
+ enum class Direction {
+ kLinearToSRGB,
+ kSRGBToLinear,
+ };
+ SkSRGBGammaColorFilter(Direction dir) : fDir(dir) {}
+
+#if SK_SUPPORT_GPU
+ sk_sp<GrFragmentProcessor> asFragmentProcessor(GrContext* x, SkColorSpace* cs) const override {
+ switch (fDir) {
+ case Direction::kLinearToSRGB:
+ return GrSRGBEffect::Make(GrSRGBEffect::Mode::kLinearToSRGB);
+ case Direction::kSRGBToLinear:
+ return GrSRGBEffect::Make(GrSRGBEffect::Mode::kSRGBToLinear);
+ }
+ return nullptr;
+ }
+#endif
+
+ SK_TO_STRING_OVERRIDE()
+
+ SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkSRGBGammaColorFilter)
+
+ void onAppendStages(SkRasterPipeline* p, SkColorSpace*, SkArenaAlloc* alloc,
+ bool shaderIsOpaque) const override {
+ switch (fDir) {
+ case Direction::kLinearToSRGB:
+ p->append(SkRasterPipeline::to_srgb);
+ break;
+ case Direction::kSRGBToLinear:
+ p->append_from_srgb(shaderIsOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
+ break;
+ }
+ }
+
+protected:
+ void flatten(SkWriteBuffer& buffer) const override {
+ buffer.write32(static_cast<uint32_t>(fDir));
+ }
+
+private:
+ const Direction fDir;
+
+ friend class SkColorFilter;
+ typedef SkColorFilter INHERITED;
+};
+
+sk_sp<SkFlattenable> SkSRGBGammaColorFilter::CreateProc(SkReadBuffer& buffer) {
+ uint32_t dir = buffer.read32();
+ if (dir <= 1) {
+ return sk_sp<SkFlattenable>(new SkSRGBGammaColorFilter(static_cast<Direction>(dir)));
+ }
+ buffer.validate(false);
+ return nullptr;
+}
+
+#ifndef SK_IGNORE_TO_STRING
+void SkSRGBGammaColorFilter::toString(SkString* str) const {
+ str->append("srgbgamma");
+}
+#endif
+
+sk_sp<SkColorFilter> SkColorFilter::MakeLinearToSRGBGamma() {
+ return sk_sp<SkColorFilter>(new SkSRGBGammaColorFilter(
+ SkSRGBGammaColorFilter::Direction::kLinearToSRGB));
+}
+
+sk_sp<SkColorFilter> SkColorFilter::MakeSRGBToLinearGamma() {
+ return sk_sp<SkColorFilter>(new SkSRGBGammaColorFilter(
+ SkSRGBGammaColorFilter::Direction::kSRGBToLinear));
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
#include "SkModeColorFilter.h"
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkColorFilter)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkComposeColorFilter)
SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkModeColorFilter)
+SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSRGBGammaColorFilter)
SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END
diff --git a/src/effects/SkTableColorFilter.cpp b/src/effects/SkTableColorFilter.cpp
index d44c8bd..da0071d 100644
--- a/src/effects/SkTableColorFilter.cpp
+++ b/src/effects/SkTableColorFilter.cpp
@@ -546,16 +546,6 @@
///////////////////////////////////////////////////////////////////////////////
-#ifdef SK_CPU_BENDIAN
-#else
- #define SK_A32_INDEX (3 - (SK_A32_SHIFT >> 3))
- #define SK_R32_INDEX (3 - (SK_R32_SHIFT >> 3))
- #define SK_G32_INDEX (3 - (SK_G32_SHIFT >> 3))
- #define SK_B32_INDEX (3 - (SK_B32_SHIFT >> 3))
-#endif
-
-///////////////////////////////////////////////////////////////////////////////
-
sk_sp<SkColorFilter> SkTableColorFilter::Make(const uint8_t table[256]) {
return sk_make_sp<SkTable_ColorFilter>(table, table, table, table);
}
diff --git a/tests/ApplyGammaTest.cpp b/tests/ApplyGammaTest.cpp
index dbb7210..79dbfc7 100644
--- a/tests/ApplyGammaTest.cpp
+++ b/tests/ApplyGammaTest.cpp
@@ -15,7 +15,6 @@
#include "SkColorFilter.h"
#include "SkSurface.h"
#include "SkUtils.h"
-#include "sk_tool_utils.h"
/** convert 0..1 linear value to 0..1 srgb */
static float linear_to_srgb(float linear) {
@@ -112,8 +111,8 @@
SkPaint gammaPaint;
gammaPaint.setBlendMode(SkBlendMode::kSrc);
- gammaPaint.setColorFilter(toSRGB ? sk_tool_utils::MakeLinearToSRGBColorFilter()
- : sk_tool_utils::MakeSRGBToLinearColorFilter());
+ gammaPaint.setColorFilter(toSRGB ? SkColorFilter::MakeLinearToSRGBGamma()
+ : SkColorFilter::MakeSRGBToLinearGamma());
dstCanvas->drawBitmap(bm, 0, 0, &gammaPaint);
dstCanvas->flush();
diff --git a/tools/sk_tool_utils.cpp b/tools/sk_tool_utils.cpp
index f4257f0..dff5d70 100644
--- a/tools/sk_tool_utils.cpp
+++ b/tools/sk_tool_utils.cpp
@@ -22,38 +22,6 @@
DEFINE_bool(portableFonts, false, "Use portable fonts");
-#if SK_SUPPORT_GPU
-#include "effects/GrSRGBEffect.h"
-#include "SkColorFilter.h"
-
-// Color filter that just wraps GrSRGBEffect
-class SkSRGBColorFilter : public SkColorFilter {
-public:
- static sk_sp<SkColorFilter> Make(GrSRGBEffect::Mode mode) {
- return sk_sp<SkColorFilter>(new SkSRGBColorFilter(mode));
- }
-
- sk_sp<GrFragmentProcessor> asFragmentProcessor(GrContext*, SkColorSpace*) const override {
- return GrSRGBEffect::Make(fMode);
- }
-
- void onAppendStages(SkRasterPipeline*, SkColorSpace*, SkArenaAlloc*, bool) const override {
- SK_ABORT("SkSRGBColorFilter is only implemented for GPU");
- }
- Factory getFactory() const override { return nullptr; }
-
-#ifndef SK_IGNORE_TO_STRING
- void toString(SkString* str) const override {}
-#endif
-
-private:
- SkSRGBColorFilter(GrSRGBEffect::Mode mode) : fMode(mode) {}
-
- GrSRGBEffect::Mode fMode;
- typedef SkColorFilter INHERITED;
-};
-#endif
-
namespace sk_tool_utils {
/* these are the default fonts chosen by Chrome for serif, sans-serif, and monospace */
@@ -655,14 +623,4 @@
}
}
-#if SK_SUPPORT_GPU
-sk_sp<SkColorFilter> MakeLinearToSRGBColorFilter() {
- return SkSRGBColorFilter::Make(GrSRGBEffect::Mode::kLinearToSRGB);
-}
-
-sk_sp<SkColorFilter> MakeSRGBToLinearColorFilter() {
- return SkSRGBColorFilter::Make(GrSRGBEffect::Mode::kSRGBToLinear);
-}
-#endif
-
} // namespace sk_tool_utils
diff --git a/tools/sk_tool_utils.h b/tools/sk_tool_utils.h
index 111f966..6283225 100644
--- a/tools/sk_tool_utils.h
+++ b/tools/sk_tool_utils.h
@@ -256,11 +256,6 @@
bool copy_to(SkBitmap* dst, SkColorType dstCT, const SkBitmap& src);
void copy_to_g8(SkBitmap* dst, const SkBitmap& src);
-#if SK_SUPPORT_GPU
- sk_sp<SkColorFilter> MakeLinearToSRGBColorFilter();
- sk_sp<SkColorFilter> MakeSRGBToLinearColorFilter();
-#endif
-
} // namespace sk_tool_utils
#endif // sk_tool_utils_DEFINED