1 /*
2 * Copyright 2016 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkColor.h"
9 #include "SkColorMatrixFilter.h"
10 #include "SkGradientShader.h"
11 #include "SkImage.h"
12 #include "SkPM4f.h"
13 #include "SkShader.h"
14
15 #include "Test.h"
16 #include "SkRandom.h"
17
18 const float kTolerance = 1.0f / (1 << 20);
19
nearly_equal(float a,float b,float tol=kTolerance)20 static bool nearly_equal(float a, float b, float tol = kTolerance) {
21 SkASSERT(tol >= 0);
22 return fabsf(a - b) <= tol;
23 }
24
nearly_equal(const SkPM4f a,const SkPM4f & b,float tol=kTolerance)25 static bool nearly_equal(const SkPM4f a, const SkPM4f& b, float tol = kTolerance) {
26 for (int i = 0; i < 4; ++i) {
27 if (!nearly_equal(a.fVec[i], b.fVec[i], tol)) {
28 return false;
29 }
30 }
31 return true;
32 }
33
DEF_TEST(SkColor4f_FromColor,reporter)34 DEF_TEST(SkColor4f_FromColor, reporter) {
35 const struct {
36 SkColor fC;
37 SkColor4f fC4;
38 } recs[] = {
39 { SK_ColorBLACK, { 1, 0, 0, 0 } },
40 { SK_ColorWHITE, { 1, 1, 1, 1 } },
41 { SK_ColorRED, { 1, 1, 0, 0 } },
42 { SK_ColorGREEN, { 1, 0, 1, 0 } },
43 { SK_ColorBLUE, { 1, 0, 0, 1 } },
44 { 0, { 0, 0, 0, 0 } },
45 { 0x55AAFF00, { 1/3.0f, 2/3.0f, 1, 0 } },
46 };
47
48 for (const auto& r : recs) {
49 SkColor4f c4 = SkColor4f::FromColor(r.fC);
50 REPORTER_ASSERT(reporter, c4 == r.fC4);
51 }
52 }
53
DEF_TEST(Color4f_premul,reporter)54 DEF_TEST(Color4f_premul, reporter) {
55 SkRandom rand;
56
57 for (int i = 0; i < 1000000; ++i) {
58 // First just test opaque colors, so that the premul should be exact
59 SkColor4f c4 {
60 1, rand.nextUScalar1(), rand.nextUScalar1(), rand.nextUScalar1()
61 };
62 SkPM4f pm4 = c4.premul();
63 REPORTER_ASSERT(reporter, pm4.fVec[SK_A_INDEX] == c4.fA);
64 REPORTER_ASSERT(reporter, pm4.fVec[SK_R_INDEX] == c4.fA * c4.fR);
65 REPORTER_ASSERT(reporter, pm4.fVec[SK_G_INDEX] == c4.fA * c4.fG);
66 REPORTER_ASSERT(reporter, pm4.fVec[SK_B_INDEX] == c4.fA * c4.fB);
67
68 // We compare with a tolerance, in case our premul multiply is implemented at slightly
69 // different precision than the test code.
70 c4.fA = rand.nextUScalar1();
71 pm4 = c4.premul();
72 REPORTER_ASSERT(reporter, pm4.fVec[SK_A_INDEX] == c4.fA);
73 REPORTER_ASSERT(reporter, nearly_equal(pm4.fVec[SK_R_INDEX], c4.fA * c4.fR));
74 REPORTER_ASSERT(reporter, nearly_equal(pm4.fVec[SK_G_INDEX], c4.fA * c4.fG));
75 REPORTER_ASSERT(reporter, nearly_equal(pm4.fVec[SK_B_INDEX], c4.fA * c4.fB));
76 }
77 }
78
79 //////////////////////////////////////////////////////////////////////////////////////////////////
80
make_mode_cf()81 static SkColorFilter* make_mode_cf() {
82 return SkColorFilter::CreateModeFilter(0xFFBB8855, SkXfermode::kPlus_Mode);
83 }
84
make_mx_cf()85 static SkColorFilter* make_mx_cf() {
86 const float mx[] = {
87 0.5f, 0, 0, 0, 0.1f,
88 0, 0.5f, 0, 0, 0.2f,
89 0, 0, 1, 0, -0.1f,
90 0, 0, 0, 1, 0,
91 };
92 return SkColorMatrixFilter::Create(mx);
93 }
94
make_compose_cf()95 static SkColorFilter* make_compose_cf() {
96 SkAutoTUnref<SkColorFilter> cf0(make_mode_cf());
97 SkAutoTUnref<SkColorFilter> cf1(make_mx_cf());
98 return SkColorFilter::CreateComposeFilter(cf0, cf1);
99 }
100
make_color_sh()101 static SkShader* make_color_sh() { return SkShader::CreateColorShader(0xFFBB8855); }
102
make_image_sh()103 static SkShader* make_image_sh() {
104 const SkImageInfo info = SkImageInfo::MakeN32Premul(2, 2);
105 const SkPMColor pixels[] {
106 SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
107 SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
108 SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
109 SkPackARGB32(0xFF, 0xBB, 0x88, 0x55),
110 };
111 SkAutoTUnref<SkImage> image(SkImage::NewRasterCopy(info, pixels, sizeof(SkPMColor) * 2));
112 return image->newShader(SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);
113 }
114
make_grad_sh()115 static SkShader* make_grad_sh() {
116 const SkPoint pts[] {{ 0, 0 }, { 100, 100 }};
117 const SkColor colors[] { SK_ColorRED, SK_ColorBLUE };
118 return SkGradientShader::CreateLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
119 }
120
make_cf_sh()121 static SkShader* make_cf_sh() {
122 SkAutoTUnref<SkColorFilter> filter(make_mx_cf());
123 SkAutoTUnref<SkShader> shader(make_color_sh());
124 return shader->newWithColorFilter(filter);
125 }
126
compare_spans(const SkPM4f span4f[],const SkPMColor span4b[],int count,skiatest::Reporter * reporter,float tolerance=1.0f/255)127 static void compare_spans(const SkPM4f span4f[], const SkPMColor span4b[], int count,
128 skiatest::Reporter* reporter, float tolerance = 1.0f/255) {
129 for (int i = 0; i < count; ++i) {
130 SkPM4f c0 = SkPM4f::FromPMColor(span4b[i]);
131 SkPM4f c1 = span4f[i];
132 REPORTER_ASSERT(reporter, nearly_equal(c0, c1, tolerance));
133 }
134 }
135
DEF_TEST(Color4f_shader,reporter)136 DEF_TEST(Color4f_shader, reporter) {
137 struct {
138 SkShader* (*fFact)();
139 bool fSupports4f;
140 float fTolerance;
141 } recs[] = {
142 { make_color_sh, true, 1.0f/255 },
143 // PMColor 4f gradients are interpolated in 255-multiplied values, so we need a
144 // slightly relaxed tolerance to accommodate the cumulative precision deviation.
145 { make_grad_sh, true, 1.001f/255 },
146 { make_image_sh, false, 1.0f/255 },
147 { make_cf_sh, true, 1.0f/255 },
148 };
149
150 SkPaint paint;
151 for (const auto& rec : recs) {
152 uint32_t storage[200];
153 paint.setShader(rec.fFact())->unref();
154 // Encourage 4f context selection. At some point we may need
155 // to instantiate two separate contexts for optimal 4b/4f selection.
156 const SkShader::ContextRec contextRec(paint, SkMatrix::I(), nullptr,
157 SkShader::ContextRec::kPM4f_DstType);
158 SkASSERT(paint.getShader()->contextSize(contextRec) <= sizeof(storage));
159 SkShader::Context* ctx = paint.getShader()->createContext(contextRec, storage);
160 if (rec.fSupports4f) {
161 const int N = 100;
162 SkPM4f buffer4f[N];
163 ctx->shadeSpan4f(0, 0, buffer4f, N);
164 SkPMColor buffer4b[N];
165 ctx->shadeSpan(0, 0, buffer4b, N);
166 compare_spans(buffer4f, buffer4b, N, reporter, rec.fTolerance);
167 }
168 ctx->~Context();
169 }
170 }
171
DEF_TEST(Color4f_colorfilter,reporter)172 DEF_TEST(Color4f_colorfilter, reporter) {
173 struct {
174 SkColorFilter* (*fFact)();
175 bool fSupports4f;
176 } recs[] = {
177 { make_mode_cf, true },
178 { make_mx_cf, true },
179 { make_compose_cf, true },
180 };
181
182 // prepare the src
183 const int N = 100;
184 SkPMColor src4b[N];
185 SkPM4f src4f[N];
186 SkRandom rand;
187 for (int i = 0; i < N; ++i) {
188 src4b[i] = SkPreMultiplyColor(rand.nextU());
189 src4f[i] = SkPM4f::FromPMColor(src4b[i]);
190 }
191 // confirm that our srcs are (nearly) equal
192 compare_spans(src4f, src4b, N, reporter);
193
194 for (const auto& rec : recs) {
195 SkAutoTUnref<SkColorFilter> filter(rec.fFact());
196 SkPMColor dst4b[N];
197 filter->filterSpan(src4b, N, dst4b);
198 SkPM4f dst4f[N];
199 filter->filterSpan4f(src4f, N, dst4f);
200 compare_spans(dst4f, dst4b, N, reporter);
201 }
202 }
203
204 ///////////////////////////////////////////////////////////////////////////////////////////////////
205
206 typedef SkPM4f (*SkXfermodeProc4f)(const SkPM4f& src, const SkPM4f& dst);
207
compare_procs(SkXfermodeProc proc32,SkXfermodeProc4f proc4f)208 static bool compare_procs(SkXfermodeProc proc32, SkXfermodeProc4f proc4f) {
209 const float kTolerance = 1.0f / 255;
210
211 const SkColor colors[] = {
212 0, 0xFF000000, 0xFFFFFFFF, 0x80FF0000
213 };
214
215 for (auto s32 : colors) {
216 SkPMColor s_pm32 = SkPreMultiplyColor(s32);
217 SkPM4f s_pm4f = SkColor4f::FromColor(s32).premul();
218 for (auto d32 : colors) {
219 SkPMColor d_pm32 = SkPreMultiplyColor(d32);
220 SkPM4f d_pm4f = SkColor4f::FromColor(d32).premul();
221
222 SkPMColor r32 = proc32(s_pm32, d_pm32);
223 SkPM4f r4f = proc4f(s_pm4f, d_pm4f);
224
225 SkPM4f r32_4f = SkPM4f::FromPMColor(r32);
226 if (!nearly_equal(r4f, r32_4f, kTolerance)) {
227 return false;
228 }
229 }
230 }
231 return true;
232 }
233
234 // Check that our Proc and Proc4f return (nearly) the same results
235 //
DEF_TEST(Color4f_xfermode_proc4f,reporter)236 DEF_TEST(Color4f_xfermode_proc4f, reporter) {
237 // TODO: extend xfermodes so that all cases can be tested.
238 //
239 for (int mode = SkXfermode::kClear_Mode; mode <= SkXfermode::kScreen_Mode; ++mode) {
240 SkXfermodeProc proc32 = SkXfermode::GetProc((SkXfermode::Mode)mode);
241 SkXfermodeProc4f proc4f = SkXfermode::GetProc4f((SkXfermode::Mode)mode);
242 REPORTER_ASSERT(reporter, compare_procs(proc32, proc4f));
243 }
244 }
245