1 /*
2  * Copyright 2015 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 "SkBitmap.h"
9 #include "SkCanvas.h"
10 #include "SkColorPriv.h"
11 #include "SkConvertPixels.h"
12 #include "SkData.h"
13 #include "SkImageInfoPriv.h"
14 #include "SkHalf.h"
15 #include "SkMask.h"
16 #include "SkNx.h"
17 #include "SkPM4f.h"
18 #include "SkPixmap.h"
19 #include "SkReadPixelsRec.h"
20 #include "SkSurface.h"
21 #include "SkUtils.h"
22 
reset(const SkPixmap & pm,void (* unlock)(void *),void * ctx)23 void SkAutoPixmapUnlock::reset(const SkPixmap& pm, void (*unlock)(void*), void* ctx) {
24     SkASSERT(pm.addr() != nullptr);
25 
26     this->unlock();
27     fPixmap = pm;
28     fUnlockProc = unlock;
29     fUnlockContext = ctx;
30     fIsLocked = true;
31 }
32 
33 /////////////////////////////////////////////////////////////////////////////////////////////////
34 
reset()35 void SkPixmap::reset() {
36     fPixels = nullptr;
37     fCTable = nullptr;
38     fRowBytes = 0;
39     fInfo = SkImageInfo::MakeUnknown();
40 }
41 
reset(const SkImageInfo & info,const void * addr,size_t rowBytes,SkColorTable * ct)42 void SkPixmap::reset(const SkImageInfo& info, const void* addr, size_t rowBytes, SkColorTable* ct) {
43     if (addr) {
44         SkASSERT(info.validRowBytes(rowBytes));
45     }
46     fPixels = addr;
47     fCTable = ct;
48     fRowBytes = rowBytes;
49     fInfo = info;
50 }
51 
reset(const SkMask & src)52 bool SkPixmap::reset(const SkMask& src) {
53     if (SkMask::kA8_Format == src.fFormat) {
54         this->reset(SkImageInfo::MakeA8(src.fBounds.width(), src.fBounds.height()),
55                     src.fImage, src.fRowBytes, nullptr);
56         return true;
57     }
58     this->reset();
59     return false;
60 }
61 
setColorSpace(sk_sp<SkColorSpace> cs)62 void SkPixmap::setColorSpace(sk_sp<SkColorSpace> cs) {
63     fInfo = fInfo.makeColorSpace(std::move(cs));
64 }
65 
extractSubset(SkPixmap * result,const SkIRect & subset) const66 bool SkPixmap::extractSubset(SkPixmap* result, const SkIRect& subset) const {
67     SkIRect srcRect, r;
68     srcRect.set(0, 0, this->width(), this->height());
69     if (!r.intersect(srcRect, subset)) {
70         return false;   // r is empty (i.e. no intersection)
71     }
72 
73     // If the upper left of the rectangle was outside the bounds of this SkBitmap, we should have
74     // exited above.
75     SkASSERT(static_cast<unsigned>(r.fLeft) < static_cast<unsigned>(this->width()));
76     SkASSERT(static_cast<unsigned>(r.fTop) < static_cast<unsigned>(this->height()));
77 
78     const void* pixels = nullptr;
79     if (fPixels) {
80         const size_t bpp = fInfo.bytesPerPixel();
81         pixels = (const uint8_t*)fPixels + r.fTop * fRowBytes + r.fLeft * bpp;
82     }
83     result->reset(fInfo.makeWH(r.width(), r.height()), pixels, fRowBytes, fCTable);
84     return true;
85 }
86 
readPixels(const SkImageInfo & dstInfo,void * dstPixels,size_t dstRB,int x,int y) const87 bool SkPixmap::readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRB, int x, int y)
88 const {
89     if (!SkImageInfoValidConversion(dstInfo, fInfo)) {
90         return false;
91     }
92 
93     SkReadPixelsRec rec(dstInfo, dstPixels, dstRB, x, y);
94     if (!rec.trim(fInfo.width(), fInfo.height())) {
95         return false;
96     }
97 
98     const void* srcPixels = this->addr(rec.fX, rec.fY);
99     const SkImageInfo srcInfo = fInfo.makeWH(rec.fInfo.width(), rec.fInfo.height());
100     SkConvertPixels(rec.fInfo, rec.fPixels, rec.fRowBytes, srcInfo, srcPixels, this->rowBytes(),
101                     this->ctable(), SkTransferFunctionBehavior::kRespect);
102     return true;
103 }
104 
pack_8888_to_4444(unsigned a,unsigned r,unsigned g,unsigned b)105 static uint16_t pack_8888_to_4444(unsigned a, unsigned r, unsigned g, unsigned b) {
106     unsigned pixel = (SkA32To4444(a) << SK_A4444_SHIFT) |
107     (SkR32To4444(r) << SK_R4444_SHIFT) |
108     (SkG32To4444(g) << SK_G4444_SHIFT) |
109     (SkB32To4444(b) << SK_B4444_SHIFT);
110     return SkToU16(pixel);
111 }
112 
erase(SkColor color,const SkIRect & inArea) const113 bool SkPixmap::erase(SkColor color, const SkIRect& inArea) const {
114     if (nullptr == fPixels) {
115         return false;
116     }
117     SkIRect area;
118     if (!area.intersect(this->bounds(), inArea)) {
119         return false;
120     }
121 
122     U8CPU a = SkColorGetA(color);
123     U8CPU r = SkColorGetR(color);
124     U8CPU g = SkColorGetG(color);
125     U8CPU b = SkColorGetB(color);
126 
127     int height = area.height();
128     const int width = area.width();
129     const int rowBytes = this->rowBytes();
130 
131     switch (this->colorType()) {
132         case kGray_8_SkColorType: {
133             if (255 != a) {
134                 r = SkMulDiv255Round(r, a);
135                 g = SkMulDiv255Round(g, a);
136                 b = SkMulDiv255Round(b, a);
137             }
138             int gray = SkComputeLuminance(r, g, b);
139             uint8_t* p = this->writable_addr8(area.fLeft, area.fTop);
140             while (--height >= 0) {
141                 memset(p, gray, width);
142                 p += rowBytes;
143             }
144             break;
145         }
146         case kAlpha_8_SkColorType: {
147             uint8_t* p = this->writable_addr8(area.fLeft, area.fTop);
148             while (--height >= 0) {
149                 memset(p, a, width);
150                 p += rowBytes;
151             }
152             break;
153         }
154         case kARGB_4444_SkColorType:
155         case kRGB_565_SkColorType: {
156             uint16_t* p = this->writable_addr16(area.fLeft, area.fTop);
157             uint16_t v;
158 
159             // make rgb premultiplied
160             if (255 != a) {
161                 r = SkMulDiv255Round(r, a);
162                 g = SkMulDiv255Round(g, a);
163                 b = SkMulDiv255Round(b, a);
164             }
165 
166             if (kARGB_4444_SkColorType == this->colorType()) {
167                 v = pack_8888_to_4444(a, r, g, b);
168             } else {
169                 v = SkPackRGB16(r >> (8 - SK_R16_BITS),
170                                 g >> (8 - SK_G16_BITS),
171                                 b >> (8 - SK_B16_BITS));
172             }
173             while (--height >= 0) {
174                 sk_memset16(p, v, width);
175                 p = (uint16_t*)((char*)p + rowBytes);
176             }
177             break;
178         }
179         case kBGRA_8888_SkColorType:
180         case kRGBA_8888_SkColorType: {
181             uint32_t* p = this->writable_addr32(area.fLeft, area.fTop);
182 
183             if (255 != a && kPremul_SkAlphaType == this->alphaType()) {
184                 r = SkMulDiv255Round(r, a);
185                 g = SkMulDiv255Round(g, a);
186                 b = SkMulDiv255Round(b, a);
187             }
188             uint32_t v = kRGBA_8888_SkColorType == this->colorType()
189                              ? SkPackARGB_as_RGBA(a, r, g, b)
190                              : SkPackARGB_as_BGRA(a, r, g, b);
191 
192             while (--height >= 0) {
193                 sk_memset32(p, v, width);
194                 p = (uint32_t*)((char*)p + rowBytes);
195             }
196             break;
197         }
198         case kRGBA_F16_SkColorType:
199             // The colorspace is unspecified, so assume linear just like getColor().
200             this->erase(SkColor4f{(1 / 255.0f) * r,
201                                   (1 / 255.0f) * g,
202                                   (1 / 255.0f) * b,
203                                   (1 / 255.0f) * a}, &area);
204             break;
205         default:
206             return false; // no change, so don't call notifyPixelsChanged()
207     }
208     return true;
209 }
210 
erase(const SkColor4f & origColor,const SkIRect * subset) const211 bool SkPixmap::erase(const SkColor4f& origColor, const SkIRect* subset) const {
212     SkPixmap pm;
213     if (subset) {
214         if (!this->extractSubset(&pm, *subset)) {
215             return false;
216         }
217     } else {
218         pm = *this;
219     }
220 
221     const SkColor4f color = origColor.pin();
222 
223     if (kRGBA_F16_SkColorType != pm.colorType()) {
224         return pm.erase(color.toSkColor());
225     }
226 
227     const uint64_t half4 = color.premul().toF16();
228     for (int y = 0; y < pm.height(); ++y) {
229         sk_memset64(pm.writable_addr64(0, y), half4, pm.width());
230     }
231     return true;
232 }
233 
scalePixels(const SkPixmap & dst,SkFilterQuality quality) const234 bool SkPixmap::scalePixels(const SkPixmap& dst, SkFilterQuality quality) const {
235     // Can't do anthing with empty src or dst
236     if (this->width() <= 0 || this->height() <= 0 || dst.width() <= 0 || dst.height() <= 0) {
237         return false;
238     }
239 
240     // no scaling involved?
241     if (dst.width() == this->width() && dst.height() == this->height()) {
242         return this->readPixels(dst);
243     }
244 
245     SkBitmap bitmap;
246     if (!bitmap.installPixels(*this)) {
247         return false;
248     }
249     bitmap.setIsVolatile(true); // so we don't try to cache it
250 
251     auto surface(SkSurface::MakeRasterDirect(dst.info(), dst.writable_addr(), dst.rowBytes()));
252     if (!surface) {
253         return false;
254     }
255 
256     SkPaint paint;
257     paint.setFilterQuality(quality);
258     paint.setBlendMode(SkBlendMode::kSrc);
259     surface->getCanvas()->drawBitmapRect(bitmap, SkRect::MakeIWH(dst.width(), dst.height()),
260                                          &paint);
261     return true;
262 }
263 
264 //////////////////////////////////////////////////////////////////////////////////////////////////
265 
getColor(int x,int y) const266 SkColor SkPixmap::getColor(int x, int y) const {
267     SkASSERT(this->addr());
268     SkASSERT((unsigned)x < (unsigned)this->width());
269     SkASSERT((unsigned)y < (unsigned)this->height());
270     switch (this->colorType()) {
271         case kGray_8_SkColorType: {
272             uint8_t value = *this->addr8(x, y);
273             return SkColorSetRGB(value, value, value);
274         }
275         case kAlpha_8_SkColorType: {
276             return SkColorSetA(0, *this->addr8(x, y));
277         }
278         case kIndex_8_SkColorType: {
279             SkASSERT(this->ctable());
280             SkPMColor pmColor = (*this->ctable())[*this->addr8(x, y)];
281             return SkUnPreMultiply::PMColorToColor(pmColor);
282         }
283         case kRGB_565_SkColorType: {
284             return SkPixel16ToColor(*this->addr16(x, y));
285         }
286         case kARGB_4444_SkColorType: {
287             uint16_t value = *this->addr16(x, y);
288             SkPMColor c = SkPixel4444ToPixel32(value);
289             return SkUnPreMultiply::PMColorToColor(c);
290         }
291         case kBGRA_8888_SkColorType: {
292             uint32_t value = *this->addr32(x, y);
293             SkPMColor c = SkSwizzle_BGRA_to_PMColor(value);
294             return SkUnPreMultiply::PMColorToColor(c);
295         }
296         case kRGBA_8888_SkColorType: {
297             uint32_t value = *this->addr32(x, y);
298             SkPMColor c = SkSwizzle_RGBA_to_PMColor(value);
299             return SkUnPreMultiply::PMColorToColor(c);
300         }
301         case kRGBA_F16_SkColorType: {
302              const uint64_t* addr =
303                  (const uint64_t*)fPixels + y * (fRowBytes >> 3) + x;
304              Sk4f p4 = SkHalfToFloat_finite_ftz(*addr);
305              if (p4[3]) {
306                  float inva = 1 / p4[3];
307                  p4 = p4 * Sk4f(inva, inva, inva, 1);
308              }
309              SkColor c;
310              SkNx_cast<uint8_t>(p4 * Sk4f(255) + Sk4f(0.5f)).store(&c);
311              // p4 is RGBA, but we want BGRA, so we need to swap next
312              return SkSwizzle_RB(c);
313         }
314         default:
315             SkDEBUGFAIL("");
316             return SkColorSetARGB(0, 0, 0, 0);
317     }
318 }
319 
computeIsOpaque() const320 bool SkPixmap::computeIsOpaque() const {
321     const int height = this->height();
322     const int width = this->width();
323 
324     switch (this->colorType()) {
325         case kAlpha_8_SkColorType: {
326             unsigned a = 0xFF;
327             for (int y = 0; y < height; ++y) {
328                 const uint8_t* row = this->addr8(0, y);
329                 for (int x = 0; x < width; ++x) {
330                     a &= row[x];
331                 }
332                 if (0xFF != a) {
333                     return false;
334                 }
335             }
336             return true;
337         } break;
338         case kIndex_8_SkColorType: {
339             const SkColorTable* ctable = this->ctable();
340             if (nullptr == ctable) {
341                 return false;
342             }
343             const SkPMColor* table = ctable->readColors();
344             SkPMColor c = (SkPMColor)~0;
345             for (int i = ctable->count() - 1; i >= 0; --i) {
346                 c &= table[i];
347             }
348             return 0xFF == SkGetPackedA32(c);
349         } break;
350         case kRGB_565_SkColorType:
351         case kGray_8_SkColorType:
352             return true;
353             break;
354         case kARGB_4444_SkColorType: {
355             unsigned c = 0xFFFF;
356             for (int y = 0; y < height; ++y) {
357                 const SkPMColor16* row = this->addr16(0, y);
358                 for (int x = 0; x < width; ++x) {
359                     c &= row[x];
360                 }
361                 if (0xF != SkGetPackedA4444(c)) {
362                     return false;
363                 }
364             }
365             return true;
366         } break;
367         case kBGRA_8888_SkColorType:
368         case kRGBA_8888_SkColorType: {
369             SkPMColor c = (SkPMColor)~0;
370             for (int y = 0; y < height; ++y) {
371                 const SkPMColor* row = this->addr32(0, y);
372                 for (int x = 0; x < width; ++x) {
373                     c &= row[x];
374                 }
375                 if (0xFF != SkGetPackedA32(c)) {
376                     return false;
377                 }
378             }
379             return true;
380         }
381         case kRGBA_F16_SkColorType: {
382             const SkHalf* row = (const SkHalf*)this->addr();
383             for (int y = 0; y < height; ++y) {
384                 for (int x = 0; x < width; ++x) {
385                     if (row[4 * x + 3] < SK_Half1) {
386                         return false;
387                     }
388                 }
389                 row += this->rowBytes() >> 1;
390             }
391             return true;
392         }
393         default:
394             break;
395     }
396     return false;
397 }
398