1/*
2 * Copyright 2014 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 "sk_tool_utils.h"
9#include "sk_tool_utils_flags.h"
10
11#include "Resources.h"
12#include "SkBitmap.h"
13#include "SkCanvas.h"
14#include "SkCommonFlags.h"
15#include "SkFontMgr.h"
16#include "SkFontStyle.h"
17#include "SkPixelRef.h"
18#include "SkPoint3.h"
19#include "SkShader.h"
20#include "SkTestScalerContext.h"
21#include "SkTextBlob.h"
22
23DEFINE_bool(portableFonts, false, "Use portable fonts");
24
25#if SK_SUPPORT_GPU
26#include "effects/GrSRGBEffect.h"
27#include "SkColorFilter.h"
28
29// Color filter that just wraps GrSRGBEffect
30class SkSRGBColorFilter : public SkColorFilter {
31public:
32    static sk_sp<SkColorFilter> Make(GrSRGBEffect::Mode mode) {
33        return sk_sp<SkColorFilter>(new SkSRGBColorFilter(mode));
34    }
35
36    sk_sp<GrFragmentProcessor> asFragmentProcessor(GrContext*, SkColorSpace*) const override {
37        return GrSRGBEffect::Make(fMode);
38    }
39
40    void filterSpan(const SkPMColor src[], int count, SkPMColor dst[]) const override {
41        SK_ABORT("SkSRGBColorFilter is only implemented for GPU");
42    }
43    Factory getFactory() const override { return nullptr; }
44
45#ifndef SK_IGNORE_TO_STRING
46    void toString(SkString* str) const override {}
47#endif
48
49private:
50    SkSRGBColorFilter(GrSRGBEffect::Mode mode) : fMode(mode) {}
51
52    GrSRGBEffect::Mode fMode;
53    typedef SkColorFilter INHERITED;
54};
55#endif
56
57namespace sk_tool_utils {
58
59/* these are the default fonts chosen by Chrome for serif, sans-serif, and monospace */
60static const char* gStandardFontNames[][3] = {
61    { "Times", "Helvetica", "Courier" }, // Mac
62    { "Times New Roman", "Helvetica", "Courier" }, // iOS
63    { "Times New Roman", "Arial", "Courier New" }, // Win
64    { "Times New Roman", "Arial", "Monospace" }, // Ubuntu
65    { "serif", "sans-serif", "monospace" }, // Android
66    { "Tinos", "Arimo", "Cousine" } // ChromeOS
67};
68
69const char* platform_font_name(const char* name) {
70    SkString platform = major_platform_os_name();
71    int index;
72    if (!strcmp(name, "serif")) {
73        index = 0;
74    } else if (!strcmp(name, "san-serif")) {
75        index = 1;
76    } else if (!strcmp(name, "monospace")) {
77        index = 2;
78    } else {
79        return name;
80    }
81    if (platform.equals("Mac")) {
82        return gStandardFontNames[0][index];
83    }
84    if (platform.equals("iOS")) {
85        return gStandardFontNames[1][index];
86    }
87    if (platform.equals("Win")) {
88        return gStandardFontNames[2][index];
89    }
90    if (platform.equals("Ubuntu")) {
91        return gStandardFontNames[3][index];
92    }
93    if (platform.equals("Android")) {
94        return gStandardFontNames[4][index];
95    }
96    if (platform.equals("ChromeOS")) {
97        return gStandardFontNames[5][index];
98    }
99    return name;
100}
101
102const char* platform_os_emoji() {
103    const char* osName = platform_os_name();
104    if (!strcmp(osName, "Android") || !strcmp(osName, "Ubuntu")) {
105        return "CBDT";
106    }
107    if (!strncmp(osName, "Mac", 3) || !strncmp(osName, "iOS", 3)) {
108        return "SBIX";
109    }
110    if (!strncmp(osName, "Win", 3)) {
111        return "COLR";
112    }
113    return "";
114}
115
116sk_sp<SkTypeface> emoji_typeface() {
117    if (!strcmp(sk_tool_utils::platform_os_emoji(), "CBDT")) {
118        return MakeResourceAsTypeface("/fonts/Funkster.ttf");
119    }
120    if (!strcmp(sk_tool_utils::platform_os_emoji(), "SBIX")) {
121        return SkTypeface::MakeFromName("Apple Color Emoji", SkFontStyle());
122    }
123    if (!strcmp(sk_tool_utils::platform_os_emoji(), "COLR")) {
124        sk_sp<SkFontMgr> fm(SkFontMgr::RefDefault());
125        const char *colorEmojiFontName = "Segoe UI Emoji";
126        sk_sp<SkTypeface> typeface(fm->matchFamilyStyle(colorEmojiFontName, SkFontStyle()));
127        if (typeface) {
128            return typeface;
129        }
130        sk_sp<SkTypeface> fallback(fm->matchFamilyStyleCharacter(
131            colorEmojiFontName, SkFontStyle(), nullptr /* bcp47 */, 0 /* bcp47Count */,
132            0x1f4b0 /* character: �� */));
133        if (fallback) {
134            return fallback;
135        }
136        // If we don't have Segoe UI Emoji and can't find a fallback, try Segoe UI Symbol.
137        // Windows 7 does not have Segoe UI Emoji; Segoe UI Symbol has the (non - color) emoji.
138        return SkTypeface::MakeFromName("Segoe UI Symbol", SkFontStyle());
139    }
140    return nullptr;
141}
142
143const char* emoji_sample_text() {
144    if (!strcmp(sk_tool_utils::platform_os_emoji(), "CBDT")) {
145        return "Hamburgefons";
146    }
147    if (!strcmp(sk_tool_utils::platform_os_emoji(), "SBIX") ||
148        !strcmp(sk_tool_utils::platform_os_emoji(), "COLR"))
149    {
150        return "\xF0\x9F\x92\xB0" "\xF0\x9F\x8F\xA1" "\xF0\x9F\x8E\x85"  // ������
151               "\xF0\x9F\x8D\xAA" "\xF0\x9F\x8D\x95" "\xF0\x9F\x9A\x80"  // ������
152               "\xF0\x9F\x9A\xBB" "\xF0\x9F\x92\xA9" "\xF0\x9F\x93\xB7" // ������
153               "\xF0\x9F\x93\xA6" // ��
154               "\xF0\x9F\x87\xBA" "\xF0\x9F\x87\xB8" "\xF0\x9F\x87\xA6"; // ������
155    }
156    return "";
157}
158
159const char* platform_os_name() {
160    for (int index = 0; index < FLAGS_key.count(); index += 2) {
161        if (!strcmp("os", FLAGS_key[index])) {
162            return FLAGS_key[index + 1];
163        }
164    }
165    // when running SampleApp or dm without a --key pair, omit the platform name
166    return "";
167}
168
169// omit version number in returned value
170SkString major_platform_os_name() {
171    SkString name;
172    for (int index = 0; index < FLAGS_key.count(); index += 2) {
173        if (!strcmp("os", FLAGS_key[index])) {
174            const char* platform = FLAGS_key[index + 1];
175            const char* end = platform;
176            while (*end && (*end < '0' || *end > '9')) {
177                ++end;
178            }
179            name.append(platform, end - platform);
180            break;
181        }
182    }
183    return name;
184}
185
186const char* platform_extra_config(const char* config) {
187    for (int index = 0; index < FLAGS_key.count(); index += 2) {
188        if (!strcmp("extra_config", FLAGS_key[index]) && !strcmp(config, FLAGS_key[index + 1])) {
189            return config;
190        }
191    }
192    return "";
193}
194
195const char* colortype_name(SkColorType ct) {
196    switch (ct) {
197        case kUnknown_SkColorType:      return "Unknown";
198        case kAlpha_8_SkColorType:      return "Alpha_8";
199        case kIndex_8_SkColorType:      return "Index_8";
200        case kARGB_4444_SkColorType:    return "ARGB_4444";
201        case kRGB_565_SkColorType:      return "RGB_565";
202        case kRGBA_8888_SkColorType:    return "RGBA_8888";
203        case kBGRA_8888_SkColorType:    return "BGRA_8888";
204        case kRGBA_F16_SkColorType:     return "RGBA_F16";
205        default:
206            SkASSERT(false);
207            return "unexpected colortype";
208    }
209}
210
211SkColor color_to_565(SkColor color) {
212    SkPMColor pmColor = SkPreMultiplyColor(color);
213    U16CPU color16 = SkPixel32ToPixel16(pmColor);
214    return SkPixel16ToColor(color16);
215}
216
217sk_sp<SkTypeface> create_portable_typeface(const char* name, SkFontStyle style) {
218    return create_font(name, style);
219}
220
221void set_portable_typeface(SkPaint* paint, const char* name, SkFontStyle style) {
222    paint->setTypeface(create_font(name, style));
223}
224
225void write_pixels(SkCanvas* canvas, const SkBitmap& bitmap, int x, int y,
226                  SkColorType colorType, SkAlphaType alphaType) {
227    SkBitmap tmp(bitmap);
228    tmp.lockPixels();
229
230    const SkImageInfo info = SkImageInfo::Make(tmp.width(), tmp.height(), colorType, alphaType);
231
232    canvas->writePixels(info, tmp.getPixels(), tmp.rowBytes(), x, y);
233}
234
235sk_sp<SkShader> create_checkerboard_shader(SkColor c1, SkColor c2, int size) {
236    SkBitmap bm;
237    bm.allocPixels(SkImageInfo::MakeS32(2 * size, 2 * size, kPremul_SkAlphaType));
238    bm.eraseColor(c1);
239    bm.eraseArea(SkIRect::MakeLTRB(0, 0, size, size), c2);
240    bm.eraseArea(SkIRect::MakeLTRB(size, size, 2 * size, 2 * size), c2);
241    return SkShader::MakeBitmapShader(
242            bm, SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode);
243}
244
245SkBitmap create_checkerboard_bitmap(int w, int h, SkColor c1, SkColor c2, int checkSize) {
246    SkBitmap bitmap;
247    bitmap.allocPixels(SkImageInfo::MakeS32(w, h, kPremul_SkAlphaType));
248    SkCanvas canvas(bitmap);
249
250    sk_tool_utils::draw_checkerboard(&canvas, c1, c2, checkSize);
251    return bitmap;
252}
253
254void draw_checkerboard(SkCanvas* canvas, SkColor c1, SkColor c2, int size) {
255    SkPaint paint;
256    paint.setShader(create_checkerboard_shader(c1, c2, size));
257    paint.setBlendMode(SkBlendMode::kSrc);
258    canvas->drawPaint(paint);
259}
260
261SkBitmap create_string_bitmap(int w, int h, SkColor c, int x, int y,
262                              int textSize, const char* str) {
263    SkBitmap bitmap;
264    bitmap.allocN32Pixels(w, h);
265    SkCanvas canvas(bitmap);
266
267    SkPaint paint;
268    paint.setAntiAlias(true);
269    sk_tool_utils::set_portable_typeface(&paint);
270    paint.setColor(c);
271    paint.setTextSize(SkIntToScalar(textSize));
272
273    canvas.clear(0x00000000);
274    canvas.drawText(str, strlen(str), SkIntToScalar(x), SkIntToScalar(y), paint);
275
276    // Tag data as sRGB (without doing any color space conversion). Color-space aware configs
277    // will process this correctly but legacy configs will render as if this returned N32.
278    SkBitmap result;
279    result.setInfo(SkImageInfo::MakeS32(w, h, kPremul_SkAlphaType));
280    result.setPixelRef(sk_ref_sp(bitmap.pixelRef()), 0, 0);
281    return result;
282}
283
284void add_to_text_blob(SkTextBlobBuilder* builder, const char* text, const SkPaint& origPaint,
285                      SkScalar x, SkScalar y) {
286    SkPaint paint(origPaint);
287    SkTDArray<uint16_t> glyphs;
288
289    size_t len = strlen(text);
290    glyphs.append(paint.textToGlyphs(text, len, nullptr));
291    paint.textToGlyphs(text, len, glyphs.begin());
292
293    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
294    const SkTextBlobBuilder::RunBuffer& run = builder->allocRun(paint, glyphs.count(), x, y,
295                                                                nullptr);
296    memcpy(run.glyphs, glyphs.begin(), glyphs.count() * sizeof(uint16_t));
297}
298
299static inline void norm_to_rgb(SkBitmap* bm, int x, int y, const SkVector3& norm) {
300    SkASSERT(SkScalarNearlyEqual(norm.length(), 1.0f));
301    unsigned char r = static_cast<unsigned char>((0.5f * norm.fX + 0.5f) * 255);
302    unsigned char g = static_cast<unsigned char>((-0.5f * norm.fY + 0.5f) * 255);
303    unsigned char b = static_cast<unsigned char>((0.5f * norm.fZ + 0.5f) * 255);
304    *bm->getAddr32(x, y) = SkPackARGB32(0xFF, r, g, b);
305}
306
307void create_hemi_normal_map(SkBitmap* bm, const SkIRect& dst) {
308    const SkPoint center = SkPoint::Make(dst.fLeft + (dst.width() / 2.0f),
309                                         dst.fTop + (dst.height() / 2.0f));
310    const SkPoint halfSize = SkPoint::Make(dst.width() / 2.0f, dst.height() / 2.0f);
311
312    SkVector3 norm;
313
314    for (int y = dst.fTop; y < dst.fBottom; ++y) {
315        for (int x = dst.fLeft; x < dst.fRight; ++x) {
316            norm.fX = (x + 0.5f - center.fX) / halfSize.fX;
317            norm.fY = (y + 0.5f - center.fY) / halfSize.fY;
318
319            SkScalar tmp = norm.fX * norm.fX + norm.fY * norm.fY;
320            if (tmp >= 1.0f) {
321                norm.set(0.0f, 0.0f, 1.0f);
322            } else {
323                norm.fZ = sqrtf(1.0f - tmp);
324            }
325
326            norm_to_rgb(bm, x, y, norm);
327        }
328    }
329}
330
331void create_frustum_normal_map(SkBitmap* bm, const SkIRect& dst) {
332    const SkPoint center = SkPoint::Make(dst.fLeft + (dst.width() / 2.0f),
333                                         dst.fTop + (dst.height() / 2.0f));
334
335    SkIRect inner = dst;
336    inner.inset(dst.width()/4, dst.height()/4);
337
338    SkPoint3 norm;
339    const SkPoint3 left =  SkPoint3::Make(-SK_ScalarRoot2Over2, 0.0f, SK_ScalarRoot2Over2);
340    const SkPoint3 up =    SkPoint3::Make(0.0f, -SK_ScalarRoot2Over2, SK_ScalarRoot2Over2);
341    const SkPoint3 right = SkPoint3::Make(SK_ScalarRoot2Over2,  0.0f, SK_ScalarRoot2Over2);
342    const SkPoint3 down =  SkPoint3::Make(0.0f,  SK_ScalarRoot2Over2, SK_ScalarRoot2Over2);
343
344    for (int y = dst.fTop; y < dst.fBottom; ++y) {
345        for (int x = dst.fLeft; x < dst.fRight; ++x) {
346            if (inner.contains(x, y)) {
347                norm.set(0.0f, 0.0f, 1.0f);
348            } else {
349                SkScalar locX = x + 0.5f - center.fX;
350                SkScalar locY = y + 0.5f - center.fY;
351
352                if (locX >= 0.0f) {
353                    if (locY > 0.0f) {
354                        norm = locX >= locY ? right : down;   // LR corner
355                    } else {
356                        norm = locX > -locY ? right : up;     // UR corner
357                    }
358                } else {
359                    if (locY > 0.0f) {
360                        norm = -locX > locY ? left : down;    // LL corner
361                    } else {
362                        norm = locX > locY ? up : left;       // UL corner
363                    }
364                }
365            }
366
367            norm_to_rgb(bm, x, y, norm);
368        }
369    }
370}
371
372void create_tetra_normal_map(SkBitmap* bm, const SkIRect& dst) {
373    const SkPoint center = SkPoint::Make(dst.fLeft + (dst.width() / 2.0f),
374                                         dst.fTop + (dst.height() / 2.0f));
375
376    static const SkScalar k1OverRoot3 = 0.5773502692f;
377
378    SkPoint3 norm;
379    const SkPoint3 leftUp =  SkPoint3::Make(-k1OverRoot3, -k1OverRoot3, k1OverRoot3);
380    const SkPoint3 rightUp = SkPoint3::Make(k1OverRoot3,  -k1OverRoot3, k1OverRoot3);
381    const SkPoint3 down =  SkPoint3::Make(0.0f,  SK_ScalarRoot2Over2, SK_ScalarRoot2Over2);
382
383    for (int y = dst.fTop; y < dst.fBottom; ++y) {
384        for (int x = dst.fLeft; x < dst.fRight; ++x) {
385            SkScalar locX = x + 0.5f - center.fX;
386            SkScalar locY = y + 0.5f - center.fY;
387
388            if (locX >= 0.0f) {
389                if (locY > 0.0f) {
390                    norm = locX >= locY ? rightUp : down;   // LR corner
391                } else {
392                    norm = rightUp;
393                }
394            } else {
395                if (locY > 0.0f) {
396                    norm = -locX > locY ? leftUp : down;    // LL corner
397                } else {
398                    norm = leftUp;
399                }
400            }
401
402            norm_to_rgb(bm, x, y, norm);
403        }
404    }
405}
406
407#if defined(_MSC_VER)
408    // MSVC takes ~2 minutes to compile this function with optimization.
409    // We don't really care to wait that long for this function.
410    #pragma optimize("", off)
411#endif
412void make_big_path(SkPath& path) {
413    #include "BigPathBench.inc"
414}
415
416static float gaussian2d_value(int x, int y, float sigma) {
417    // don't bother with the scale term since we're just going to normalize the
418    // kernel anyways
419    float temp = expf(-(x*x + y*y)/(2*sigma*sigma));
420    return temp;
421}
422
423static float* create_2d_kernel(float sigma, int* filterSize) {
424    // We will actually take 2*halfFilterSize+1 samples (i.e., our filter kernel
425    // sizes are always odd)
426    int halfFilterSize = SkScalarCeilToInt(6*sigma)/2;
427    int wh = *filterSize = 2*halfFilterSize + 1;
428
429    float* temp = new float[wh*wh];
430
431    float filterTot = 0.0f;
432    for (int yOff = 0; yOff < wh; ++yOff) {
433        for (int xOff = 0; xOff < wh; ++xOff) {
434            temp[yOff*wh+xOff] = gaussian2d_value(xOff-halfFilterSize, yOff-halfFilterSize, sigma);
435
436            filterTot += temp[yOff*wh+xOff];
437        }
438    }
439
440    // normalize the kernel
441    for (int yOff = 0; yOff < wh; ++yOff) {
442        for (int xOff = 0; xOff < wh; ++xOff) {
443            temp[yOff*wh+xOff] /= filterTot;
444        }
445    }
446
447    return temp;
448}
449
450static SkPMColor blur_pixel(const SkBitmap& bm, int x, int y, float* kernel, int wh) {
451    SkASSERT(wh & 0x1);
452
453    int halfFilterSize = (wh-1)/2;
454
455    float r = 0.0f, g = 0.0f, b = 0.0f;
456    for (int yOff = 0; yOff < wh; ++yOff) {
457        int ySamp = y + yOff - halfFilterSize;
458
459        if (ySamp < 0) {
460            ySamp = 0;
461        } else if (ySamp > bm.height()-1) {
462            ySamp = bm.height()-1;
463        }
464
465        for (int xOff = 0; xOff < wh; ++xOff) {
466            int xSamp = x + xOff - halfFilterSize;
467
468            if (xSamp < 0) {
469                xSamp = 0;
470            } else if (xSamp > bm.width()-1) {
471                xSamp = bm.width()-1;
472            }
473
474            float filter = kernel[yOff*wh + xOff];
475
476            SkPMColor c = *bm.getAddr32(xSamp, ySamp);
477
478            r += SkGetPackedR32(c) * filter;
479            g += SkGetPackedG32(c) * filter;
480            b += SkGetPackedB32(c) * filter;
481        }
482    }
483
484    U8CPU r8, g8, b8;
485
486    r8 = (U8CPU) (r+0.5f);
487    g8 = (U8CPU) (g+0.5f);
488    b8 = (U8CPU) (b+0.5f);
489
490    return SkPackARGB32(255, r8, g8, b8);
491}
492
493SkBitmap slow_blur(const SkBitmap& src, float sigma) {
494    SkBitmap dst;
495
496    dst.allocN32Pixels(src.width(), src.height(), true);
497
498    int wh;
499    std::unique_ptr<float[]> kernel(create_2d_kernel(sigma, &wh));
500
501    for (int y = 0; y < src.height(); ++y) {
502        for (int x = 0; x < src.width(); ++x) {
503            *dst.getAddr32(x, y) = blur_pixel(src, x, y, kernel.get(), wh);
504        }
505    }
506
507    return dst;
508}
509
510// compute the intersection point between the diagonal and the ellipse in the
511// lower right corner
512static SkPoint intersection(SkScalar w, SkScalar h) {
513    SkASSERT(w > 0.0f || h > 0.0f);
514
515    return SkPoint::Make(w / SK_ScalarSqrt2, h / SK_ScalarSqrt2);
516}
517
518// Use the intersection of the corners' diagonals with their ellipses to shrink
519// the bounding rect
520SkRect compute_central_occluder(const SkRRect& rr) {
521    const SkRect r = rr.getBounds();
522
523    SkScalar newL = r.fLeft, newT = r.fTop, newR = r.fRight, newB = r.fBottom;
524
525    SkVector radii = rr.radii(SkRRect::kUpperLeft_Corner);
526    if (!radii.isZero()) {
527        SkPoint p = intersection(radii.fX, radii.fY);
528
529        newL = SkTMax(newL, r.fLeft + radii.fX - p.fX);
530        newT = SkTMax(newT, r.fTop + radii.fY - p.fY);
531    }
532
533    radii = rr.radii(SkRRect::kUpperRight_Corner);
534    if (!radii.isZero()) {
535        SkPoint p = intersection(radii.fX, radii.fY);
536
537        newR = SkTMin(newR, r.fRight + p.fX - radii.fX);
538        newT = SkTMax(newT, r.fTop + radii.fY - p.fY);
539    }
540
541    radii = rr.radii(SkRRect::kLowerRight_Corner);
542    if (!radii.isZero()) {
543        SkPoint p = intersection(radii.fX, radii.fY);
544
545        newR = SkTMin(newR, r.fRight + p.fX - radii.fX);
546        newB = SkTMin(newB, r.fBottom - radii.fY + p.fY);
547    }
548
549    radii = rr.radii(SkRRect::kLowerLeft_Corner);
550    if (!radii.isZero()) {
551        SkPoint p = intersection(radii.fX, radii.fY);
552
553        newL = SkTMax(newL, r.fLeft + radii.fX - p.fX);
554        newB = SkTMin(newB, r.fBottom - radii.fY + p.fY);
555    }
556
557    return SkRect::MakeLTRB(newL, newT, newR, newB);
558}
559
560// The widest inset rect
561SkRect compute_widest_occluder(const SkRRect& rr) {
562    const SkRect& r = rr.getBounds();
563
564    const SkVector& ul = rr.radii(SkRRect::kUpperLeft_Corner);
565    const SkVector& ur = rr.radii(SkRRect::kUpperRight_Corner);
566    const SkVector& lr = rr.radii(SkRRect::kLowerRight_Corner);
567    const SkVector& ll = rr.radii(SkRRect::kLowerLeft_Corner);
568
569    SkScalar maxT = SkTMax(ul.fY, ur.fY);
570    SkScalar maxB = SkTMax(ll.fY, lr.fY);
571
572    return SkRect::MakeLTRB(r.fLeft, r.fTop + maxT, r.fRight, r.fBottom - maxB);
573
574}
575
576// The tallest inset rect
577SkRect compute_tallest_occluder(const SkRRect& rr) {
578    const SkRect& r = rr.getBounds();
579
580    const SkVector& ul = rr.radii(SkRRect::kUpperLeft_Corner);
581    const SkVector& ur = rr.radii(SkRRect::kUpperRight_Corner);
582    const SkVector& lr = rr.radii(SkRRect::kLowerRight_Corner);
583    const SkVector& ll = rr.radii(SkRRect::kLowerLeft_Corner);
584
585    SkScalar maxL = SkTMax(ul.fX, ll.fX);
586    SkScalar maxR = SkTMax(ur.fX, lr.fX);
587
588    return SkRect::MakeLTRB(r.fLeft + maxL, r.fTop, r.fRight - maxR, r.fBottom);
589}
590
591void copy_to_g8(SkBitmap* dst, const SkBitmap& src) {
592    SkASSERT(kBGRA_8888_SkColorType == src.colorType() ||
593             kRGBA_8888_SkColorType == src.colorType());
594
595    SkImageInfo grayInfo = src.info().makeColorType(kGray_8_SkColorType);
596    dst->allocPixels(grayInfo);
597    uint8_t* dst8 = (uint8_t*)dst->getPixels();
598    const uint32_t* src32 = (const uint32_t*)src.getPixels();
599
600    const int w = src.width();
601    const int h = src.height();
602    const bool isBGRA = (kBGRA_8888_SkColorType == src.colorType());
603    for (int y = 0; y < h; ++y) {
604        if (isBGRA) {
605            // BGRA
606            for (int x = 0; x < w; ++x) {
607                uint32_t s = src32[x];
608                dst8[x] = SkComputeLuminance((s >> 16) & 0xFF, (s >> 8) & 0xFF, s & 0xFF);
609            }
610        } else {
611            // RGBA
612            for (int x = 0; x < w; ++x) {
613                uint32_t s = src32[x];
614                dst8[x] = SkComputeLuminance(s & 0xFF, (s >> 8) & 0xFF, (s >> 16) & 0xFF);
615            }
616        }
617        src32 = (const uint32_t*)((const char*)src32 + src.rowBytes());
618        dst8 += dst->rowBytes();
619    }
620}
621
622#if SK_SUPPORT_GPU
623sk_sp<SkColorFilter> MakeLinearToSRGBColorFilter() {
624    return SkSRGBColorFilter::Make(GrSRGBEffect::Mode::kLinearToSRGB);
625}
626
627sk_sp<SkColorFilter> MakeSRGBToLinearColorFilter() {
628    return SkSRGBColorFilter::Make(GrSRGBEffect::Mode::kSRGBToLinear);
629}
630#endif
631
632}  // namespace sk_tool_utils
633