Move SkColorMatrixFilter implementation to core.
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1648933002
Review URL: https://codereview.chromium.org/1648933002
diff --git a/src/core/SkColorMatrixFilterRowMajor255.cpp b/src/core/SkColorMatrixFilterRowMajor255.cpp
new file mode 100644
index 0000000..6fdfa0b
--- /dev/null
+++ b/src/core/SkColorMatrixFilterRowMajor255.cpp
@@ -0,0 +1,422 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkColorMatrixFilterRowMajor255.h"
+#include "SkColorPriv.h"
+#include "SkNx.h"
+#include "SkReadBuffer.h"
+#include "SkWriteBuffer.h"
+#include "SkUnPreMultiply.h"
+#include "SkString.h"
+
+#define SK_PMORDER_INDEX_A (SK_A32_SHIFT / 8)
+#define SK_PMORDER_INDEX_R (SK_R32_SHIFT / 8)
+#define SK_PMORDER_INDEX_G (SK_G32_SHIFT / 8)
+#define SK_PMORDER_INDEX_B (SK_B32_SHIFT / 8)
+
+static void transpose_to_pmorder(float dst[20], const float src[20]) {
+ const float* srcR = src + 0;
+ const float* srcG = src + 5;
+ const float* srcB = src + 10;
+ const float* srcA = src + 15;
+
+ for (int i = 0; i < 20; i += 4) {
+ dst[i + SK_PMORDER_INDEX_A] = *srcA++;
+ dst[i + SK_PMORDER_INDEX_R] = *srcR++;
+ dst[i + SK_PMORDER_INDEX_G] = *srcG++;
+ dst[i + SK_PMORDER_INDEX_B] = *srcB++;
+ }
+}
+
+// src is [20] but some compilers won't accept __restrict__ on anything
+// but an raw pointer or reference
+void SkColorMatrixFilterRowMajor255::initState(const SkScalar* SK_RESTRICT src) {
+ transpose_to_pmorder(fTranspose, src);
+
+ const float* array = fMatrix;
+
+ // check if we have to munge Alpha
+ bool changesAlpha = (array[15] || array[16] || array[17] || (array[18] - 1) || array[19]);
+ bool usesAlpha = (array[3] || array[8] || array[13]);
+
+ if (changesAlpha || usesAlpha) {
+ fFlags = changesAlpha ? 0 : kAlphaUnchanged_Flag;
+ } else {
+ fFlags = kAlphaUnchanged_Flag;
+ }
+ fFlags |= kSupports4f_Flag;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+SkColorMatrixFilterRowMajor255::SkColorMatrixFilterRowMajor255(const SkScalar array[20]) {
+ memcpy(fMatrix, array, 20 * sizeof(SkScalar));
+ this->initState(array);
+}
+
+uint32_t SkColorMatrixFilterRowMajor255::getFlags() const {
+ return this->INHERITED::getFlags() | fFlags;
+}
+
+static Sk4f scale_rgb(float scale) {
+ static_assert(SkPM4f::A == 3, "Alpha is lane 3");
+ return Sk4f(scale, scale, scale, 1);
+}
+
+static Sk4f premul(const Sk4f& x) {
+ return x * scale_rgb(x.kth<SkPM4f::A>());
+}
+
+static Sk4f unpremul(const Sk4f& x) {
+ return x * scale_rgb(1 / x.kth<SkPM4f::A>()); // TODO: fast/approx invert?
+}
+
+static Sk4f clamp_0_1(const Sk4f& x) {
+ return Sk4f::Max(Sk4f::Min(x, Sk4f(1)), Sk4f(0));
+}
+
+static SkPMColor round(const Sk4f& x) {
+ SkPMColor c;
+ SkNx_cast<uint8_t>(x * Sk4f(255) + Sk4f(0.5f)).store(&c);
+ return c;
+}
+
+template <typename Adaptor, typename T>
+void filter_span(const float array[], const T src[], int count, T dst[]) {
+ // c0-c3 are already in [0,1].
+ const Sk4f c0 = Sk4f::Load(array + 0);
+ const Sk4f c1 = Sk4f::Load(array + 4);
+ const Sk4f c2 = Sk4f::Load(array + 8);
+ const Sk4f c3 = Sk4f::Load(array + 12);
+ // c4 (the translate vector) is in [0, 255]. Bring it back to [0,1].
+ const Sk4f c4 = Sk4f::Load(array + 16)*Sk4f(1.0f/255);
+
+ // todo: we could cache this in the constructor...
+ T matrix_translate_pmcolor = Adaptor::From4f(premul(clamp_0_1(c4)));
+
+ for (int i = 0; i < count; i++) {
+ Sk4f srcf = Adaptor::To4f(src[i]);
+ float srcA = srcf.kth<SkPM4f::A>();
+
+ if (0 == srcA) {
+ dst[i] = matrix_translate_pmcolor;
+ continue;
+ }
+ if (1 != srcA) {
+ srcf = unpremul(srcf);
+ }
+
+ Sk4f r4 = SkNx_dup<SK_R32_SHIFT/8>(srcf);
+ Sk4f g4 = SkNx_dup<SK_G32_SHIFT/8>(srcf);
+ Sk4f b4 = SkNx_dup<SK_B32_SHIFT/8>(srcf);
+ Sk4f a4 = SkNx_dup<SK_A32_SHIFT/8>(srcf);
+
+ // apply matrix
+ Sk4f dst4 = c0 * r4 + c1 * g4 + c2 * b4 + c3 * a4 + c4;
+
+ dst[i] = Adaptor::From4f(premul(clamp_0_1(dst4)));
+ }
+}
+
+struct SkPMColorAdaptor {
+ static SkPMColor From4f(const Sk4f& c4) {
+ return round(c4);
+ }
+ static Sk4f To4f(SkPMColor c) {
+ return SkNx_cast<float>(Sk4b::Load(&c)) * Sk4f(1.0f/255);
+ }
+};
+void SkColorMatrixFilterRowMajor255::filterSpan(const SkPMColor src[], int count, SkPMColor dst[]) const {
+ filter_span<SkPMColorAdaptor>(fTranspose, src, count, dst);
+}
+
+struct SkPM4fAdaptor {
+ static SkPM4f From4f(const Sk4f& c4) {
+ SkPM4f c;
+ c4.store(&c);
+ return c;
+ }
+ static Sk4f To4f(const SkPM4f& c) {
+ return Sk4f::Load(&c);
+ }
+};
+void SkColorMatrixFilterRowMajor255::filterSpan4f(const SkPM4f src[], int count, SkPM4f dst[]) const {
+ filter_span<SkPM4fAdaptor>(fTranspose, src, count, dst);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
+void SkColorMatrixFilterRowMajor255::flatten(SkWriteBuffer& buffer) const {
+ SkASSERT(sizeof(fMatrix)/sizeof(SkScalar) == 20);
+ buffer.writeScalarArray(fMatrix, 20);
+}
+
+SkFlattenable* SkColorMatrixFilterRowMajor255::CreateProc(SkReadBuffer& buffer) {
+ SkScalar matrix[20];
+ if (buffer.readScalarArray(matrix, 20)) {
+ return new SkColorMatrixFilterRowMajor255(matrix);
+ }
+ return nullptr;
+}
+
+bool SkColorMatrixFilterRowMajor255::asColorMatrix(SkScalar matrix[20]) const {
+ if (matrix) {
+ memcpy(matrix, fMatrix, 20 * sizeof(SkScalar));
+ }
+ return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// This code was duplicated from src/effects/SkColorMatrixc.cpp in order to be used in core.
+//////
+
+// To detect if we need to apply clamping after applying a matrix, we check if
+// any output component might go outside of [0, 255] for any combination of
+// input components in [0..255].
+// Each output component is an affine transformation of the input component, so
+// the minimum and maximum values are for any combination of minimum or maximum
+// values of input components (i.e. 0 or 255).
+// E.g. if R' = x*R + y*G + z*B + w*A + t
+// Then the maximum value will be for R=255 if x>0 or R=0 if x<0, and the
+// minimum value will be for R=0 if x>0 or R=255 if x<0.
+// Same goes for all components.
+static bool component_needs_clamping(const SkScalar row[5]) {
+ SkScalar maxValue = row[4] / 255;
+ SkScalar minValue = row[4] / 255;
+ for (int i = 0; i < 4; ++i) {
+ if (row[i] > 0)
+ maxValue += row[i];
+ else
+ minValue += row[i];
+ }
+ return (maxValue > 1) || (minValue < 0);
+}
+
+static bool needs_clamping(const SkScalar matrix[20]) {
+ return component_needs_clamping(matrix)
+ || component_needs_clamping(matrix+5)
+ || component_needs_clamping(matrix+10)
+ || component_needs_clamping(matrix+15);
+}
+
+static void set_concat(SkScalar result[20], const SkScalar outer[20], const SkScalar inner[20]) {
+ int index = 0;
+ for (int j = 0; j < 20; j += 5) {
+ for (int i = 0; i < 4; i++) {
+ result[index++] = outer[j + 0] * inner[i + 0] +
+ outer[j + 1] * inner[i + 5] +
+ outer[j + 2] * inner[i + 10] +
+ outer[j + 3] * inner[i + 15];
+ }
+ result[index++] = outer[j + 0] * inner[4] +
+ outer[j + 1] * inner[9] +
+ outer[j + 2] * inner[14] +
+ outer[j + 3] * inner[19] +
+ outer[j + 4];
+ }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// End duplication
+//////
+
+SkColorFilter* SkColorMatrixFilterRowMajor255::newComposed(const SkColorFilter* innerFilter) const {
+ SkScalar innerMatrix[20];
+ if (innerFilter->asColorMatrix(innerMatrix) && !needs_clamping(innerMatrix)) {
+ SkScalar concat[20];
+ set_concat(concat, fMatrix, innerMatrix);
+ return new SkColorMatrixFilterRowMajor255(concat);
+ }
+ return nullptr;
+}
+
+#if SK_SUPPORT_GPU
+#include "GrFragmentProcessor.h"
+#include "GrInvariantOutput.h"
+#include "glsl/GrGLSLFragmentProcessor.h"
+#include "glsl/GrGLSLFragmentShaderBuilder.h"
+#include "glsl/GrGLSLProgramDataManager.h"
+#include "glsl/GrGLSLUniformHandler.h"
+
+class ColorMatrixEffect : public GrFragmentProcessor {
+public:
+ static const GrFragmentProcessor* Create(const SkScalar matrix[20]) {
+ return new ColorMatrixEffect(matrix);
+ }
+
+ const char* name() const override { return "Color Matrix"; }
+
+ GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
+
+ class GLSLProcessor : public GrGLSLFragmentProcessor {
+ public:
+ // this class always generates the same code.
+ static void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder* b) {}
+
+ GLSLProcessor(const GrProcessor&) {}
+
+ virtual void emitCode(EmitArgs& args) override {
+ GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
+ fMatrixHandle = uniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
+ kMat44f_GrSLType, kDefault_GrSLPrecision,
+ "ColorMatrix");
+ fVectorHandle = uniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
+ kVec4f_GrSLType, kDefault_GrSLPrecision,
+ "ColorMatrixVector");
+
+ if (nullptr == args.fInputColor) {
+ // could optimize this case, but we aren't for now.
+ args.fInputColor = "vec4(1)";
+ }
+ GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
+ // The max() is to guard against 0 / 0 during unpremul when the incoming color is
+ // transparent black.
+ fragBuilder->codeAppendf("\tfloat nonZeroAlpha = max(%s.a, 0.00001);\n",
+ args.fInputColor);
+ fragBuilder->codeAppendf("\t%s = %s * vec4(%s.rgb / nonZeroAlpha, nonZeroAlpha) + %s;\n",
+ args.fOutputColor,
+ uniformHandler->getUniformCStr(fMatrixHandle),
+ args.fInputColor,
+ uniformHandler->getUniformCStr(fVectorHandle));
+ fragBuilder->codeAppendf("\t%s = clamp(%s, 0.0, 1.0);\n",
+ args.fOutputColor, args.fOutputColor);
+ fragBuilder->codeAppendf("\t%s.rgb *= %s.a;\n", args.fOutputColor, args.fOutputColor);
+ }
+
+ protected:
+ virtual void onSetData(const GrGLSLProgramDataManager& uniManager,
+ const GrProcessor& proc) override {
+ const ColorMatrixEffect& cme = proc.cast<ColorMatrixEffect>();
+ const float* m = cme.fMatrix;
+ // The GL matrix is transposed from SkColorMatrix.
+ float mt[] = {
+ m[0], m[5], m[10], m[15],
+ m[1], m[6], m[11], m[16],
+ m[2], m[7], m[12], m[17],
+ m[3], m[8], m[13], m[18],
+ };
+ static const float kScale = 1.0f / 255.0f;
+ float vec[] = {
+ m[4] * kScale, m[9] * kScale, m[14] * kScale, m[19] * kScale,
+ };
+ uniManager.setMatrix4fv(fMatrixHandle, 1, mt);
+ uniManager.set4fv(fVectorHandle, 1, vec);
+ }
+
+ private:
+ GrGLSLProgramDataManager::UniformHandle fMatrixHandle;
+ GrGLSLProgramDataManager::UniformHandle fVectorHandle;
+
+ typedef GrGLSLFragmentProcessor INHERITED;
+ };
+
+private:
+ ColorMatrixEffect(const SkScalar matrix[20]) {
+ memcpy(fMatrix, matrix, sizeof(SkScalar) * 20);
+ this->initClassID<ColorMatrixEffect>();
+ }
+
+ GrGLSLFragmentProcessor* onCreateGLSLInstance() const override {
+ return new GLSLProcessor(*this);
+ }
+
+ virtual void onGetGLSLProcessorKey(const GrGLSLCaps& caps,
+ GrProcessorKeyBuilder* b) const override {
+ GLSLProcessor::GenKey(*this, caps, b);
+ }
+
+ bool onIsEqual(const GrFragmentProcessor& s) const override {
+ const ColorMatrixEffect& cme = s.cast<ColorMatrixEffect>();
+ return 0 == memcmp(fMatrix, cme.fMatrix, sizeof(fMatrix));
+ }
+
+ void onComputeInvariantOutput(GrInvariantOutput* inout) const override {
+ // We only bother to check whether the alpha channel will be constant. If SkColorMatrix had
+ // type flags it might be worth checking the other components.
+
+ // The matrix is defined such the 4th row determines the output alpha. The first four
+ // columns of that row multiply the input r, g, b, and a, respectively, and the last column
+ // is the "translation".
+ static const uint32_t kRGBAFlags[] = {
+ kR_GrColorComponentFlag,
+ kG_GrColorComponentFlag,
+ kB_GrColorComponentFlag,
+ kA_GrColorComponentFlag
+ };
+ static const int kShifts[] = {
+ GrColor_SHIFT_R, GrColor_SHIFT_G, GrColor_SHIFT_B, GrColor_SHIFT_A,
+ };
+ enum {
+ kAlphaRowStartIdx = 15,
+ kAlphaRowTranslateIdx = 19,
+ };
+
+ SkScalar outputA = 0;
+ for (int i = 0; i < 4; ++i) {
+ // If any relevant component of the color to be passed through the matrix is non-const
+ // then we can't know the final result.
+ if (0 != fMatrix[kAlphaRowStartIdx + i]) {
+ if (!(inout->validFlags() & kRGBAFlags[i])) {
+ inout->setToUnknown(GrInvariantOutput::kWill_ReadInput);
+ return;
+ } else {
+ uint32_t component = (inout->color() >> kShifts[i]) & 0xFF;
+ outputA += fMatrix[kAlphaRowStartIdx + i] * component;
+ }
+ }
+ }
+ outputA += fMatrix[kAlphaRowTranslateIdx];
+ // We pin the color to [0,1]. This would happen to the *final* color output from the frag
+ // shader but currently the effect does not pin its own output. So in the case of over/
+ // underflow this may deviate from the actual result. Maybe the effect should pin its
+ // result if the matrix could over/underflow for any component?
+ inout->setToOther(kA_GrColorComponentFlag,
+ static_cast<uint8_t>(SkScalarPin(outputA, 0, 255)) << GrColor_SHIFT_A,
+ GrInvariantOutput::kWill_ReadInput);
+ }
+
+ SkScalar fMatrix[20];
+
+ typedef GrFragmentProcessor INHERITED;
+};
+
+GR_DEFINE_FRAGMENT_PROCESSOR_TEST(ColorMatrixEffect);
+
+const GrFragmentProcessor* ColorMatrixEffect::TestCreate(GrProcessorTestData* d) {
+ SkScalar colorMatrix[20];
+ for (size_t i = 0; i < SK_ARRAY_COUNT(colorMatrix); ++i) {
+ colorMatrix[i] = d->fRandom->nextSScalar1();
+ }
+ return ColorMatrixEffect::Create(colorMatrix);
+}
+
+const GrFragmentProcessor* SkColorMatrixFilterRowMajor255::asFragmentProcessor(GrContext*) const {
+ return ColorMatrixEffect::Create(fMatrix);
+}
+
+#endif
+
+#ifndef SK_IGNORE_TO_STRING
+void SkColorMatrixFilterRowMajor255::toString(SkString* str) const {
+ str->append("SkColorMatrixFilterRowMajor255: ");
+
+ str->append("matrix: (");
+ for (int i = 0; i < 20; ++i) {
+ str->appendScalar(fMatrix[i]);
+ if (i < 19) {
+ str->append(", ");
+ }
+ }
+ str->append(")");
+}
+#endif
+
+///////////////////////////////////////////////////////////////////////////////
+
+SkColorFilter* SkColorFilter::CreateMatrixFilterRowMajor255(const SkScalar array[20]) {
+ return new SkColorMatrixFilterRowMajor255(array);
+}