tests/SkColor4fTest.cpp - skia - Git at Google

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "SkColor.h"
 #include "SkColorMatrixFilter.h"
 #include "SkGradientShader.h"
 #include "SkImage.h"
 #include "SkPM4f.h"
 #include "SkShader.h"

 #include "Test.h"
 #include "SkRandom.h"

 const float kTolerance = 1.0f / (1 << 20);

 static bool nearly_equal(float a, float b, float tol = kTolerance) {
     SkASSERT(tol >= 0);
     return fabsf(a - b) <= tol;
 }

 static bool nearly_equal(const SkPM4f a, const SkPM4f& b, float tol = kTolerance) {
     for (int i = 0; i < 4; ++i) {
         if (!nearly_equal(a.fVec[i], b.fVec[i], tol)) {
             return false;
         }
     }
     return true;
 }

 DEF_TEST(SkColor4f_FromColor, reporter) {
     const struct {
         SkColor     fC;
         SkColor4f   fC4;
     } recs[] = {
         { SK_ColorBLACK, { 1, 0, 0, 0 } },
         { SK_ColorWHITE, { 1, 1, 1, 1 } },
         { SK_ColorRED,   { 1, 1, 0, 0 } },
         { SK_ColorGREEN, { 1, 0, 1, 0 } },
         { SK_ColorBLUE,  { 1, 0, 0, 1 } },
         { 0,             { 0, 0, 0, 0 } },
         { 0x55AAFF00,    { 1/3.0f, 2/3.0f, 1, 0 } },
     };

     for (const auto& r : recs) {
         SkColor4f c4 = SkColor4f::FromColor(r.fC);
         REPORTER_ASSERT(reporter, c4 == r.fC4);
     }
 }

 DEF_TEST(Color4f_premul, reporter) {
     SkRandom rand;

     for (int i = 0; i < 1000000; ++i) {
         // First just test opaque colors, so that the premul should be exact
         SkColor4f c4 {
             1, rand.nextUScalar1(), rand.nextUScalar1(), rand.nextUScalar1()
         };
         SkPM4f pm4 = c4.premul();
         REPORTER_ASSERT(reporter, pm4.a() == c4.fA);
         REPORTER_ASSERT(reporter, pm4.r() == c4.fA * c4.fR);
         REPORTER_ASSERT(reporter, pm4.g() == c4.fA * c4.fG);
         REPORTER_ASSERT(reporter, pm4.b() == c4.fA * c4.fB);

         // We compare with a tolerance, in case our premul multiply is implemented at slightly
         // different precision than the test code.
         c4.fA = rand.nextUScalar1();
         pm4 = c4.premul();
         REPORTER_ASSERT(reporter, pm4.fVec[SK_A_INDEX] == c4.fA);
         REPORTER_ASSERT(reporter, nearly_equal(pm4.r(), c4.fA * c4.fR));
         REPORTER_ASSERT(reporter, nearly_equal(pm4.g(), c4.fA * c4.fG));
         REPORTER_ASSERT(reporter, nearly_equal(pm4.b(), c4.fA * c4.fB));
     }
 }

 //////////////////////////////////////////////////////////////////////////////////////////////////

 static SkColorFilter* make_mode_cf() {
     return SkColorFilter::CreateModeFilter(0xFFBB8855, SkXfermode::kPlus_Mode);
 }

 static SkColorFilter* make_mx_cf() {
     const float mx[] = {
         0.5f, 0,    0, 0, 0.1f,
         0,    0.5f, 0, 0, 0.2f,
         0,    0,    1, 0, -0.1f,
         0,    0,    0, 1, 0,
     };
     return SkColorMatrixFilter::Create(mx);
 }

 static SkColorFilter* make_compose_cf() {
     SkAutoTUnref<SkColorFilter> cf0(make_mode_cf());
     SkAutoTUnref<SkColorFilter> cf1(make_mx_cf());
     return SkColorFilter::CreateComposeFilter(cf0, cf1);
 }

 static sk_sp<SkShader> make_color_sh() { return SkShader::MakeColorShader(0xFFBB8855); }

 static sk_sp<SkShader> make_image_sh() {
     const SkImageInfo info = SkImageInfo::MakeN32Premul(2, 2);
     const SkPMColor pixels[] {
         SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
         SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
         SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
         SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
     };
     sk_sp<SkImage> image(SkImage::MakeRasterCopy(SkPixmap(info, pixels, sizeof(SkPMColor) * 2)));
     return image->makeShader(SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
 }

 static sk_sp<SkShader> make_grad_sh() {
 #if 0
     const SkPoint pts[] {{ 0, 0 }, { 100, 100 }};
     const SkColor colors[] { SK_ColorRED, SK_ColorBLUE };
     return SkGradientShader::CreateLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
 #else
     // TODO: need to convert new gradient code to enforce PM4f --> RGBA order
     return make_color_sh();
 #endif
 }

 static sk_sp<SkShader> make_cf_sh() {
     SkAutoTUnref<SkColorFilter> filter(make_mx_cf());
     return make_color_sh()->makeWithColorFilter(filter);
 }

 static bool compare_spans(const SkPM4f span4f[], const SkPMColor span4b[], int count,
                           float tolerance = 1.0f/255) {
     for (int i = 0; i < count; ++i) {
         SkPM4f c0 = SkPM4f::FromPMColor(span4b[i]);
         SkPM4f c1 = span4f[i];
         if (!nearly_equal(c0, c1, tolerance)) {
             return false;
         }
     }
     return true;
 }

 DEF_TEST(Color4f_shader, reporter) {
     struct {
         sk_sp<SkShader> (*fFact)();
         bool            fSupports4f;
         float           fTolerance;
     } recs[] = {
         { make_color_sh, true,  1.0f/255   },
         // PMColor 4f gradients are interpolated in 255-multiplied values, so we need a
         // slightly relaxed tolerance to accommodate the cumulative precision deviation.
         { make_grad_sh,  true,  1.001f/255 },
         { make_image_sh, false, 1.0f/255   },
         { make_cf_sh,    true,  1.0f/255   },
     };

     SkPaint paint;
     for (const auto& rec : recs) {
         uint32_t storage[300];
         paint.setShader(rec.fFact());
         // Encourage 4f context selection. At some point we may need
         // to instantiate two separate contexts for optimal 4b/4f selection.
         const SkShader::ContextRec contextRec(paint, SkMatrix::I(), nullptr,
                                               SkShader::ContextRec::kPM4f_DstType);
         SkASSERT(paint.getShader()->contextSize(contextRec) <= sizeof(storage));
         SkShader::Context* ctx = paint.getShader()->createContext(contextRec, storage);
         if (rec.fSupports4f) {
             const int N = 100;
             SkPM4f buffer4f[N];
             ctx->shadeSpan4f(0, 0, buffer4f, N);
             SkPMColor buffer4b[N];
             ctx->shadeSpan(0, 0, buffer4b, N);
             REPORTER_ASSERT(reporter, compare_spans(buffer4f, buffer4b, N, rec.fTolerance));
         }
         ctx->~Context();
     }
 }

 DEF_TEST(Color4f_colorfilter, reporter) {
     struct {
         SkColorFilter* (*fFact)();
         bool           fSupports4f;
         const char*    fName;
     } recs[] = {
         { make_mode_cf,     true, "mode" },
         { make_mx_cf,       true, "matrix" },
         { make_compose_cf,  true, "compose" },
     };

     // prepare the src
     const int N = 100;
     SkPMColor src4b[N];
     SkPM4f    src4f[N];
     SkRandom rand;
     for (int i = 0; i < N; ++i) {
         src4b[i] = SkPreMultiplyColor(rand.nextU());
         src4f[i] = SkPM4f::FromPMColor(src4b[i]);
     }
     // confirm that our srcs are (nearly) equal
     REPORTER_ASSERT(reporter, compare_spans(src4f, src4b, N));

     for (const auto& rec : recs) {
         SkAutoTUnref<SkColorFilter> filter(rec.fFact());
         SkPMColor dst4b[N];
         filter->filterSpan(src4b, N, dst4b);
         SkPM4f dst4f[N];
         filter->filterSpan4f(src4f, N, dst4f);
         REPORTER_ASSERT(reporter, compare_spans(dst4f, dst4b, N));
     }
 }

 ///////////////////////////////////////////////////////////////////////////////////////////////////

 typedef SkPM4f (*SkXfermodeProc4f)(const SkPM4f& src, const SkPM4f& dst);

 static bool compare_procs(SkXfermodeProc proc32, SkXfermodeProc4f proc4f) {
     const float kTolerance = 1.0f / 255;

     const SkColor colors[] = {
         0, 0xFF000000, 0xFFFFFFFF, 0x80FF0000
     };

     for (auto s32 : colors) {
         SkPMColor s_pm32 = SkPreMultiplyColor(s32);
         SkPM4f    s_pm4f = SkColor4f::FromColor(s32).premul();
         for (auto d32 : colors) {
             SkPMColor d_pm32 = SkPreMultiplyColor(d32);
             SkPM4f    d_pm4f = SkColor4f::FromColor(d32).premul();

             SkPMColor r32 = proc32(s_pm32, d_pm32);
             SkPM4f    r4f = proc4f(s_pm4f, d_pm4f);

             SkPM4f r32_4f = SkPM4f::FromPMColor(r32);
             if (!nearly_equal(r4f, r32_4f, kTolerance)) {
                 return false;
             }
         }
     }
     return true;
 }

 // Check that our Proc and Proc4f return (nearly) the same results
 //
 DEF_TEST(Color4f_xfermode_proc4f, reporter) {
     // TODO: extend xfermodes so that all cases can be tested.
     //
     for (int mode = SkXfermode::kClear_Mode; mode <= SkXfermode::kScreen_Mode; ++mode) {
         SkXfermodeProc   proc32 = SkXfermode::GetProc((SkXfermode::Mode)mode);
         SkXfermodeProc4f proc4f = SkXfermode::GetProc4f((SkXfermode::Mode)mode);
         REPORTER_ASSERT(reporter, compare_procs(proc32, proc4f));
     }
 }
	/*
	* Copyright 2016 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "SkColor.h"
	#include "SkColorMatrixFilter.h"
	#include "SkGradientShader.h"
	#include "SkImage.h"
	#include "SkPM4f.h"
	#include "SkShader.h"

	#include "Test.h"
	#include "SkRandom.h"

	const float kTolerance = 1.0f / (1 << 20);

	static bool nearly_equal(float a, float b, float tol = kTolerance) {
	SkASSERT(tol >= 0);
	return fabsf(a - b) <= tol;
	}

	static bool nearly_equal(const SkPM4f a, const SkPM4f& b, float tol = kTolerance) {
	for (int i = 0; i < 4; ++i) {
	if (!nearly_equal(a.fVec[i], b.fVec[i], tol)) {
	return false;
	}
	}
	return true;
	}

	DEF_TEST(SkColor4f_FromColor, reporter) {
	const struct {
	SkColor fC;
	SkColor4f fC4;
	} recs[] = {
	{ SK_ColorBLACK, { 1, 0, 0, 0 } },
	{ SK_ColorWHITE, { 1, 1, 1, 1 } },
	{ SK_ColorRED, { 1, 1, 0, 0 } },
	{ SK_ColorGREEN, { 1, 0, 1, 0 } },
	{ SK_ColorBLUE, { 1, 0, 0, 1 } },
	{ 0, { 0, 0, 0, 0 } },
	{ 0x55AAFF00, { 1/3.0f, 2/3.0f, 1, 0 } },
	};

	for (const auto& r : recs) {
	SkColor4f c4 = SkColor4f::FromColor(r.fC);
	REPORTER_ASSERT(reporter, c4 == r.fC4);
	}
	}

	DEF_TEST(Color4f_premul, reporter) {
	SkRandom rand;

	for (int i = 0; i < 1000000; ++i) {
	// First just test opaque colors, so that the premul should be exact
	SkColor4f c4 {
	1, rand.nextUScalar1(), rand.nextUScalar1(), rand.nextUScalar1()
	};
	SkPM4f pm4 = c4.premul();
	REPORTER_ASSERT(reporter, pm4.a() == c4.fA);
	REPORTER_ASSERT(reporter, pm4.r() == c4.fA * c4.fR);
	REPORTER_ASSERT(reporter, pm4.g() == c4.fA * c4.fG);
	REPORTER_ASSERT(reporter, pm4.b() == c4.fA * c4.fB);

	// We compare with a tolerance, in case our premul multiply is implemented at slightly
	// different precision than the test code.
	c4.fA = rand.nextUScalar1();
	pm4 = c4.premul();
	REPORTER_ASSERT(reporter, pm4.fVec[SK_A_INDEX] == c4.fA);
	REPORTER_ASSERT(reporter, nearly_equal(pm4.r(), c4.fA * c4.fR));
	REPORTER_ASSERT(reporter, nearly_equal(pm4.g(), c4.fA * c4.fG));
	REPORTER_ASSERT(reporter, nearly_equal(pm4.b(), c4.fA * c4.fB));
	}
	}

	//////////////////////////////////////////////////////////////////////////////////////////////////

	static SkColorFilter* make_mode_cf() {
	return SkColorFilter::CreateModeFilter(0xFFBB8855, SkXfermode::kPlus_Mode);
	}

	static SkColorFilter* make_mx_cf() {
	const float mx[] = {
	0.5f, 0, 0, 0, 0.1f,
	0, 0.5f, 0, 0, 0.2f,
	0, 0, 1, 0, -0.1f,
	0, 0, 0, 1, 0,
	};
	return SkColorMatrixFilter::Create(mx);
	}

	static SkColorFilter* make_compose_cf() {
	SkAutoTUnref<SkColorFilter> cf0(make_mode_cf());
	SkAutoTUnref<SkColorFilter> cf1(make_mx_cf());
	return SkColorFilter::CreateComposeFilter(cf0, cf1);
	}

	static sk_sp<SkShader> make_color_sh() { return SkShader::MakeColorShader(0xFFBB8855); }

	static sk_sp<SkShader> make_image_sh() {
	const SkImageInfo info = SkImageInfo::MakeN32Premul(2, 2);
	const SkPMColor pixels[] {
	SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
	SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
	SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
	SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
	};
	sk_sp<SkImage> image(SkImage::MakeRasterCopy(SkPixmap(info, pixels, sizeof(SkPMColor) * 2)));
	return image->makeShader(SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
	}

	static sk_sp<SkShader> make_grad_sh() {
	#if 0
	const SkPoint pts[] {{ 0, 0 }, { 100, 100 }};
	const SkColor colors[] { SK_ColorRED, SK_ColorBLUE };
	return SkGradientShader::CreateLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
	#else
	// TODO: need to convert new gradient code to enforce PM4f --> RGBA order
	return make_color_sh();
	#endif
	}

	static sk_sp<SkShader> make_cf_sh() {
	SkAutoTUnref<SkColorFilter> filter(make_mx_cf());
	return make_color_sh()->makeWithColorFilter(filter);
	}

	static bool compare_spans(const SkPM4f span4f[], const SkPMColor span4b[], int count,
	float tolerance = 1.0f/255) {
	for (int i = 0; i < count; ++i) {
	SkPM4f c0 = SkPM4f::FromPMColor(span4b[i]);
	SkPM4f c1 = span4f[i];
	if (!nearly_equal(c0, c1, tolerance)) {
	return false;
	}
	}
	return true;
	}

	DEF_TEST(Color4f_shader, reporter) {
	struct {
	sk_sp<SkShader> (*fFact)();
	bool fSupports4f;
	float fTolerance;
	} recs[] = {
	{ make_color_sh, true, 1.0f/255 },
	// PMColor 4f gradients are interpolated in 255-multiplied values, so we need a
	// slightly relaxed tolerance to accommodate the cumulative precision deviation.
	{ make_grad_sh, true, 1.001f/255 },
	{ make_image_sh, false, 1.0f/255 },
	{ make_cf_sh, true, 1.0f/255 },
	};

	SkPaint paint;
	for (const auto& rec : recs) {
	uint32_t storage[300];
	paint.setShader(rec.fFact());
	// Encourage 4f context selection. At some point we may need
	// to instantiate two separate contexts for optimal 4b/4f selection.
	const SkShader::ContextRec contextRec(paint, SkMatrix::I(), nullptr,
	SkShader::ContextRec::kPM4f_DstType);
	SkASSERT(paint.getShader()->contextSize(contextRec) <= sizeof(storage));
	SkShader::Context* ctx = paint.getShader()->createContext(contextRec, storage);
	if (rec.fSupports4f) {
	const int N = 100;
	SkPM4f buffer4f[N];
	ctx->shadeSpan4f(0, 0, buffer4f, N);
	SkPMColor buffer4b[N];
	ctx->shadeSpan(0, 0, buffer4b, N);
	REPORTER_ASSERT(reporter, compare_spans(buffer4f, buffer4b, N, rec.fTolerance));
	}
	ctx->~Context();
	}
	}

	DEF_TEST(Color4f_colorfilter, reporter) {
	struct {
	SkColorFilter* (*fFact)();
	bool fSupports4f;
	const char* fName;
	} recs[] = {
	{ make_mode_cf, true, "mode" },
	{ make_mx_cf, true, "matrix" },
	{ make_compose_cf, true, "compose" },
	};

	// prepare the src
	const int N = 100;
	SkPMColor src4b[N];
	SkPM4f src4f[N];
	SkRandom rand;
	for (int i = 0; i < N; ++i) {
	src4b[i] = SkPreMultiplyColor(rand.nextU());
	src4f[i] = SkPM4f::FromPMColor(src4b[i]);
	}
	// confirm that our srcs are (nearly) equal
	REPORTER_ASSERT(reporter, compare_spans(src4f, src4b, N));

	for (const auto& rec : recs) {
	SkAutoTUnref<SkColorFilter> filter(rec.fFact());
	SkPMColor dst4b[N];
	filter->filterSpan(src4b, N, dst4b);
	SkPM4f dst4f[N];
	filter->filterSpan4f(src4f, N, dst4f);
	REPORTER_ASSERT(reporter, compare_spans(dst4f, dst4b, N));
	}
	}

	///////////////////////////////////////////////////////////////////////////////////////////////////

	typedef SkPM4f (*SkXfermodeProc4f)(const SkPM4f& src, const SkPM4f& dst);

	static bool compare_procs(SkXfermodeProc proc32, SkXfermodeProc4f proc4f) {
	const float kTolerance = 1.0f / 255;

	const SkColor colors[] = {
	0, 0xFF000000, 0xFFFFFFFF, 0x80FF0000
	};

	for (auto s32 : colors) {
	SkPMColor s_pm32 = SkPreMultiplyColor(s32);
	SkPM4f s_pm4f = SkColor4f::FromColor(s32).premul();
	for (auto d32 : colors) {
	SkPMColor d_pm32 = SkPreMultiplyColor(d32);
	SkPM4f d_pm4f = SkColor4f::FromColor(d32).premul();

	SkPMColor r32 = proc32(s_pm32, d_pm32);
	SkPM4f r4f = proc4f(s_pm4f, d_pm4f);

	SkPM4f r32_4f = SkPM4f::FromPMColor(r32);
	if (!nearly_equal(r4f, r32_4f, kTolerance)) {
	return false;
	}
	}
	}
	return true;
	}

	// Check that our Proc and Proc4f return (nearly) the same results
	//
	DEF_TEST(Color4f_xfermode_proc4f, reporter) {
	// TODO: extend xfermodes so that all cases can be tested.
	//
	for (int mode = SkXfermode::kClear_Mode; mode <= SkXfermode::kScreen_Mode; ++mode) {
	SkXfermodeProc proc32 = SkXfermode::GetProc((SkXfermode::Mode)mode);
	SkXfermodeProc4f proc4f = SkXfermode::GetProc4f((SkXfermode::Mode)mode);
	REPORTER_ASSERT(reporter, compare_procs(proc32, proc4f));
	}
	}