1/*
2 * Copyright 2013 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 "include/core/SkBitmap.h"
9#include "include/core/SkTypes.h"
10#include "include/private/SkColorData.h"
11#include "include/private/SkHalf.h"
12#include "include/private/SkImageInfoPriv.h"
13#include "include/private/SkNx.h"
14#include "include/private/SkTo.h"
15#include "include/private/SkVx.h"
16#include "src/core/SkMathPriv.h"
17#include "src/core/SkMipmap.h"
18#include <new>
19
20//
21// ColorTypeFilter is the "Type" we pass to some downsample template functions.
22// It controls how we expand a pixel into a large type, with space between each component,
23// so we can then perform our simple filter (either box or triangle) and store the intermediates
24// in the expanded type.
25//
26
27struct ColorTypeFilter_8888 {
28 typedef uint32_t Type;
29 static Sk4h Expand(uint32_t x) {
30 return SkNx_cast<uint16_t>(Sk4b::Load(&x));
31 }
32 static uint32_t Compact(const Sk4h& x) {
33 uint32_t r;
34 SkNx_cast<uint8_t>(x).store(&r);
35 return r;
36 }
37};
38
39struct ColorTypeFilter_565 {
40 typedef uint16_t Type;
41 static uint32_t Expand(uint16_t x) {
42 return (x & ~SK_G16_MASK_IN_PLACE) | ((x & SK_G16_MASK_IN_PLACE) << 16);
43 }
44 static uint16_t Compact(uint32_t x) {
45 return ((x & ~SK_G16_MASK_IN_PLACE) & 0xFFFF) | ((x >> 16) & SK_G16_MASK_IN_PLACE);
46 }
47};
48
49struct ColorTypeFilter_4444 {
50 typedef uint16_t Type;
51 static uint32_t Expand(uint16_t x) {
52 return (x & 0xF0F) | ((x & ~0xF0F) << 12);
53 }
54 static uint16_t Compact(uint32_t x) {
55 return (x & 0xF0F) | ((x >> 12) & ~0xF0F);
56 }
57};
58
59struct ColorTypeFilter_8 {
60 typedef uint8_t Type;
61 static unsigned Expand(unsigned x) {
62 return x;
63 }
64 static uint8_t Compact(unsigned x) {
65 return (uint8_t)x;
66 }
67};
68
69struct ColorTypeFilter_Alpha_F16 {
70 typedef uint16_t Type;
71 static Sk4f Expand(uint16_t x) {
72 return SkHalfToFloat_finite_ftz((uint64_t) x); // expand out to four lanes
73
74 }
75 static uint16_t Compact(const Sk4f& x) {
76 uint64_t r;
77 SkFloatToHalf_finite_ftz(x).store(&r);
78 return r & 0xFFFF; // but ignore the extra 3 here
79 }
80};
81
82struct ColorTypeFilter_RGBA_F16 {
83 typedef uint64_t Type; // SkHalf x4
84 static Sk4f Expand(uint64_t x) {
85 return SkHalfToFloat_finite_ftz(x);
86 }
87 static uint64_t Compact(const Sk4f& x) {
88 uint64_t r;
89 SkFloatToHalf_finite_ftz(x).store(&r);
90 return r;
91 }
92};
93
94struct ColorTypeFilter_88 {
95 typedef uint16_t Type;
96 static uint32_t Expand(uint16_t x) {
97 return (x & 0xFF) | ((x & ~0xFF) << 8);
98 }
99 static uint16_t Compact(uint32_t x) {
100 return (x & 0xFF) | ((x >> 8) & ~0xFF);
101 }
102};
103
104struct ColorTypeFilter_1616 {
105 typedef uint32_t Type;
106 static uint64_t Expand(uint32_t x) {
107 return (x & 0xFFFF) | ((x & ~0xFFFF) << 16);
108 }
109 static uint16_t Compact(uint64_t x) {
110 return (x & 0xFFFF) | ((x >> 16) & ~0xFFFF);
111 }
112};
113
114struct ColorTypeFilter_F16F16 {
115 typedef uint32_t Type;
116 static Sk4f Expand(uint32_t x) {
117 return SkHalfToFloat_finite_ftz((uint64_t) x); // expand out to four lanes
118 }
119 static uint32_t Compact(const Sk4f& x) {
120 uint64_t r;
121 SkFloatToHalf_finite_ftz(x).store(&r);
122 return (uint32_t) (r & 0xFFFFFFFF); // but ignore the extra 2 here
123 }
124};
125
126struct ColorTypeFilter_16161616 {
127 typedef uint64_t Type;
128 static skvx::Vec<4, uint32_t> Expand(uint64_t x) {
129 return skvx::cast<uint32_t>(skvx::Vec<4, uint16_t>::Load(&x));
130 }
131 static uint64_t Compact(const skvx::Vec<4, uint32_t>& x) {
132 uint64_t r;
133 skvx::cast<uint16_t>(x).store(&r);
134 return r;
135 }
136};
137
138struct ColorTypeFilter_16 {
139 typedef uint16_t Type;
140 static uint32_t Expand(uint16_t x) {
141 return x;
142 }
143 static uint16_t Compact(uint32_t x) {
144 return (uint16_t) x;
145 }
146};
147
148struct ColorTypeFilter_1010102 {
149 typedef uint32_t Type;
150 static uint64_t Expand(uint64_t x) {
151 return (((x ) & 0x3ff) ) |
152 (((x >> 10) & 0x3ff) << 20) |
153 (((x >> 20) & 0x3ff) << 40) |
154 (((x >> 30) & 0x3 ) << 60);
155 }
156 static uint32_t Compact(uint64_t x) {
157 return (((x ) & 0x3ff) ) |
158 (((x >> 20) & 0x3ff) << 10) |
159 (((x >> 40) & 0x3ff) << 20) |
160 (((x >> 60) & 0x3 ) << 30);
161 }
162};
163
164template <typename T> T add_121(const T& a, const T& b, const T& c) {
165 return a + b + b + c;
166}
167
168template <typename T> T shift_right(const T& x, int bits) {
169 return x >> bits;
170}
171
172Sk4f shift_right(const Sk4f& x, int bits) {
173 return x * (1.0f / (1 << bits));
174}
175
176template <typename T> T shift_left(const T& x, int bits) {
177 return x << bits;
178}
179
180Sk4f shift_left(const Sk4f& x, int bits) {
181 return x * (1 << bits);
182}
183
184//
185// To produce each mip level, we need to filter down by 1/2 (e.g. 100x100 -> 50,50)
186// If the starting dimension is odd, we floor the size of the lower level (e.g. 101 -> 50)
187// In those (odd) cases, we use a triangle filter, with 1-pixel overlap between samplings,
188// else for even cases, we just use a 2x box filter.
189//
190// This produces 4 possible isotropic filters: 2x2 2x3 3x2 3x3 where WxH indicates the number of
191// src pixels we need to sample in each dimension to produce 1 dst pixel.
192//
193// OpenGL expects a full mipmap stack to contain anisotropic space as well.
194// This means a 100x1 image would continue down to a 50x1 image, 25x1 image...
195// Because of this, we need 4 more anisotropic filters: 1x2, 1x3, 2x1, 3x1.
196
197template <typename F> void downsample_1_2(void* dst, const void* src, size_t srcRB, int count) {
198 SkASSERT(count > 0);
199 auto p0 = static_cast<const typename F::Type*>(src);
200 auto p1 = (const typename F::Type*)((const char*)p0 + srcRB);
201 auto d = static_cast<typename F::Type*>(dst);
202
203 for (int i = 0; i < count; ++i) {
204 auto c00 = F::Expand(p0[0]);
205 auto c10 = F::Expand(p1[0]);
206
207 auto c = c00 + c10;
208 d[i] = F::Compact(shift_right(c, 1));
209 p0 += 2;
210 p1 += 2;
211 }
212}
213
214template <typename F> void downsample_1_3(void* dst, const void* src, size_t srcRB, int count) {
215 SkASSERT(count > 0);
216 auto p0 = static_cast<const typename F::Type*>(src);
217 auto p1 = (const typename F::Type*)((const char*)p0 + srcRB);
218 auto p2 = (const typename F::Type*)((const char*)p1 + srcRB);
219 auto d = static_cast<typename F::Type*>(dst);
220
221 for (int i = 0; i < count; ++i) {
222 auto c00 = F::Expand(p0[0]);
223 auto c10 = F::Expand(p1[0]);
224 auto c20 = F::Expand(p2[0]);
225
226 auto c = add_121(c00, c10, c20);
227 d[i] = F::Compact(shift_right(c, 2));
228 p0 += 2;
229 p1 += 2;
230 p2 += 2;
231 }
232}
233
234template <typename F> void downsample_2_1(void* dst, const void* src, size_t srcRB, int count) {
235 SkASSERT(count > 0);
236 auto p0 = static_cast<const typename F::Type*>(src);
237 auto d = static_cast<typename F::Type*>(dst);
238
239 for (int i = 0; i < count; ++i) {
240 auto c00 = F::Expand(p0[0]);
241 auto c01 = F::Expand(p0[1]);
242
243 auto c = c00 + c01;
244 d[i] = F::Compact(shift_right(c, 1));
245 p0 += 2;
246 }
247}
248
249template <typename F> void downsample_2_2(void* dst, const void* src, size_t srcRB, int count) {
250 SkASSERT(count > 0);
251 auto p0 = static_cast<const typename F::Type*>(src);
252 auto p1 = (const typename F::Type*)((const char*)p0 + srcRB);
253 auto d = static_cast<typename F::Type*>(dst);
254
255 for (int i = 0; i < count; ++i) {
256 auto c00 = F::Expand(p0[0]);
257 auto c01 = F::Expand(p0[1]);
258 auto c10 = F::Expand(p1[0]);
259 auto c11 = F::Expand(p1[1]);
260
261 auto c = c00 + c10 + c01 + c11;
262 d[i] = F::Compact(shift_right(c, 2));
263 p0 += 2;
264 p1 += 2;
265 }
266}
267
268template <typename F> void downsample_2_3(void* dst, const void* src, size_t srcRB, int count) {
269 SkASSERT(count > 0);
270 auto p0 = static_cast<const typename F::Type*>(src);
271 auto p1 = (const typename F::Type*)((const char*)p0 + srcRB);
272 auto p2 = (const typename F::Type*)((const char*)p1 + srcRB);
273 auto d = static_cast<typename F::Type*>(dst);
274
275 for (int i = 0; i < count; ++i) {
276 auto c00 = F::Expand(p0[0]);
277 auto c01 = F::Expand(p0[1]);
278 auto c10 = F::Expand(p1[0]);
279 auto c11 = F::Expand(p1[1]);
280 auto c20 = F::Expand(p2[0]);
281 auto c21 = F::Expand(p2[1]);
282
283 auto c = add_121(c00, c10, c20) + add_121(c01, c11, c21);
284 d[i] = F::Compact(shift_right(c, 3));
285 p0 += 2;
286 p1 += 2;
287 p2 += 2;
288 }
289}
290
291template <typename F> void downsample_3_1(void* dst, const void* src, size_t srcRB, int count) {
292 SkASSERT(count > 0);
293 auto p0 = static_cast<const typename F::Type*>(src);
294 auto d = static_cast<typename F::Type*>(dst);
295
296 auto c02 = F::Expand(p0[0]);
297 for (int i = 0; i < count; ++i) {
298 auto c00 = c02;
299 auto c01 = F::Expand(p0[1]);
300 c02 = F::Expand(p0[2]);
301
302 auto c = add_121(c00, c01, c02);
303 d[i] = F::Compact(shift_right(c, 2));
304 p0 += 2;
305 }
306}
307
308template <typename F> void downsample_3_2(void* dst, const void* src, size_t srcRB, int count) {
309 SkASSERT(count > 0);
310 auto p0 = static_cast<const typename F::Type*>(src);
311 auto p1 = (const typename F::Type*)((const char*)p0 + srcRB);
312 auto d = static_cast<typename F::Type*>(dst);
313
314 // Given pixels:
315 // a0 b0 c0 d0 e0 ...
316 // a1 b1 c1 d1 e1 ...
317 // We want:
318 // (a0 + 2*b0 + c0 + a1 + 2*b1 + c1) / 8
319 // (c0 + 2*d0 + e0 + c1 + 2*d1 + e1) / 8
320 // ...
321
322 auto c0 = F::Expand(p0[0]);
323 auto c1 = F::Expand(p1[0]);
324 auto c = c0 + c1;
325 for (int i = 0; i < count; ++i) {
326 auto a = c;
327
328 auto b0 = F::Expand(p0[1]);
329 auto b1 = F::Expand(p1[1]);
330 auto b = b0 + b0 + b1 + b1;
331
332 c0 = F::Expand(p0[2]);
333 c1 = F::Expand(p1[2]);
334 c = c0 + c1;
335
336 auto sum = a + b + c;
337 d[i] = F::Compact(shift_right(sum, 3));
338 p0 += 2;
339 p1 += 2;
340 }
341}
342
343template <typename F> void downsample_3_3(void* dst, const void* src, size_t srcRB, int count) {
344 SkASSERT(count > 0);
345 auto p0 = static_cast<const typename F::Type*>(src);
346 auto p1 = (const typename F::Type*)((const char*)p0 + srcRB);
347 auto p2 = (const typename F::Type*)((const char*)p1 + srcRB);
348 auto d = static_cast<typename F::Type*>(dst);
349
350 // Given pixels:
351 // a0 b0 c0 d0 e0 ...
352 // a1 b1 c1 d1 e1 ...
353 // a2 b2 c2 d2 e2 ...
354 // We want:
355 // (a0 + 2*b0 + c0 + 2*a1 + 4*b1 + 2*c1 + a2 + 2*b2 + c2) / 16
356 // (c0 + 2*d0 + e0 + 2*c1 + 4*d1 + 2*e1 + c2 + 2*d2 + e2) / 16
357 // ...
358
359 auto c0 = F::Expand(p0[0]);
360 auto c1 = F::Expand(p1[0]);
361 auto c2 = F::Expand(p2[0]);
362 auto c = add_121(c0, c1, c2);
363 for (int i = 0; i < count; ++i) {
364 auto a = c;
365
366 auto b0 = F::Expand(p0[1]);
367 auto b1 = F::Expand(p1[1]);
368 auto b2 = F::Expand(p2[1]);
369 auto b = shift_left(add_121(b0, b1, b2), 1);
370
371 c0 = F::Expand(p0[2]);
372 c1 = F::Expand(p1[2]);
373 c2 = F::Expand(p2[2]);
374 c = add_121(c0, c1, c2);
375
376 auto sum = a + b + c;
377 d[i] = F::Compact(shift_right(sum, 4));
378 p0 += 2;
379 p1 += 2;
380 p2 += 2;
381 }
382}
383
384///////////////////////////////////////////////////////////////////////////////////////////////////
385
386size_t SkMipmap::AllocLevelsSize(int levelCount, size_t pixelSize) {
387 if (levelCount < 0) {
388 return 0;
389 }
390 int64_t size = sk_64_mul(levelCount + 1, sizeof(Level)) + pixelSize;
391 if (!SkTFitsIn<int32_t>(size)) {
392 return 0;
393 }
394 return SkTo<int32_t>(size);
395}
396
397SkMipmap* SkMipmap::Build(const SkPixmap& src, SkDiscardableFactoryProc fact,
398 bool computeContents) {
399 typedef void FilterProc(void*, const void* srcPtr, size_t srcRB, int count);
400
401 FilterProc* proc_1_2 = nullptr;
402 FilterProc* proc_1_3 = nullptr;
403 FilterProc* proc_2_1 = nullptr;
404 FilterProc* proc_2_2 = nullptr;
405 FilterProc* proc_2_3 = nullptr;
406 FilterProc* proc_3_1 = nullptr;
407 FilterProc* proc_3_2 = nullptr;
408 FilterProc* proc_3_3 = nullptr;
409
410 const SkColorType ct = src.colorType();
411 const SkAlphaType at = src.alphaType();
412
413 switch (ct) {
414 case kRGBA_8888_SkColorType:
415 case kBGRA_8888_SkColorType:
416 proc_1_2 = downsample_1_2<ColorTypeFilter_8888>;
417 proc_1_3 = downsample_1_3<ColorTypeFilter_8888>;
418 proc_2_1 = downsample_2_1<ColorTypeFilter_8888>;
419 proc_2_2 = downsample_2_2<ColorTypeFilter_8888>;
420 proc_2_3 = downsample_2_3<ColorTypeFilter_8888>;
421 proc_3_1 = downsample_3_1<ColorTypeFilter_8888>;
422 proc_3_2 = downsample_3_2<ColorTypeFilter_8888>;
423 proc_3_3 = downsample_3_3<ColorTypeFilter_8888>;
424 break;
425 case kRGB_565_SkColorType:
426 proc_1_2 = downsample_1_2<ColorTypeFilter_565>;
427 proc_1_3 = downsample_1_3<ColorTypeFilter_565>;
428 proc_2_1 = downsample_2_1<ColorTypeFilter_565>;
429 proc_2_2 = downsample_2_2<ColorTypeFilter_565>;
430 proc_2_3 = downsample_2_3<ColorTypeFilter_565>;
431 proc_3_1 = downsample_3_1<ColorTypeFilter_565>;
432 proc_3_2 = downsample_3_2<ColorTypeFilter_565>;
433 proc_3_3 = downsample_3_3<ColorTypeFilter_565>;
434 break;
435 case kARGB_4444_SkColorType:
436 proc_1_2 = downsample_1_2<ColorTypeFilter_4444>;
437 proc_1_3 = downsample_1_3<ColorTypeFilter_4444>;
438 proc_2_1 = downsample_2_1<ColorTypeFilter_4444>;
439 proc_2_2 = downsample_2_2<ColorTypeFilter_4444>;
440 proc_2_3 = downsample_2_3<ColorTypeFilter_4444>;
441 proc_3_1 = downsample_3_1<ColorTypeFilter_4444>;
442 proc_3_2 = downsample_3_2<ColorTypeFilter_4444>;
443 proc_3_3 = downsample_3_3<ColorTypeFilter_4444>;
444 break;
445 case kAlpha_8_SkColorType:
446 case kGray_8_SkColorType:
447 proc_1_2 = downsample_1_2<ColorTypeFilter_8>;
448 proc_1_3 = downsample_1_3<ColorTypeFilter_8>;
449 proc_2_1 = downsample_2_1<ColorTypeFilter_8>;
450 proc_2_2 = downsample_2_2<ColorTypeFilter_8>;
451 proc_2_3 = downsample_2_3<ColorTypeFilter_8>;
452 proc_3_1 = downsample_3_1<ColorTypeFilter_8>;
453 proc_3_2 = downsample_3_2<ColorTypeFilter_8>;
454 proc_3_3 = downsample_3_3<ColorTypeFilter_8>;
455 break;
456 case kRGBA_F16Norm_SkColorType:
457 case kRGBA_F16_SkColorType:
458 proc_1_2 = downsample_1_2<ColorTypeFilter_RGBA_F16>;
459 proc_1_3 = downsample_1_3<ColorTypeFilter_RGBA_F16>;
460 proc_2_1 = downsample_2_1<ColorTypeFilter_RGBA_F16>;
461 proc_2_2 = downsample_2_2<ColorTypeFilter_RGBA_F16>;
462 proc_2_3 = downsample_2_3<ColorTypeFilter_RGBA_F16>;
463 proc_3_1 = downsample_3_1<ColorTypeFilter_RGBA_F16>;
464 proc_3_2 = downsample_3_2<ColorTypeFilter_RGBA_F16>;
465 proc_3_3 = downsample_3_3<ColorTypeFilter_RGBA_F16>;
466 break;
467 case kR8G8_unorm_SkColorType:
468 proc_1_2 = downsample_1_2<ColorTypeFilter_88>;
469 proc_1_3 = downsample_1_3<ColorTypeFilter_88>;
470 proc_2_1 = downsample_2_1<ColorTypeFilter_88>;
471 proc_2_2 = downsample_2_2<ColorTypeFilter_88>;
472 proc_2_3 = downsample_2_3<ColorTypeFilter_88>;
473 proc_3_1 = downsample_3_1<ColorTypeFilter_88>;
474 proc_3_2 = downsample_3_2<ColorTypeFilter_88>;
475 proc_3_3 = downsample_3_3<ColorTypeFilter_88>;
476 break;
477 case kR16G16_unorm_SkColorType:
478 proc_1_2 = downsample_1_2<ColorTypeFilter_1616>;
479 proc_1_3 = downsample_1_3<ColorTypeFilter_1616>;
480 proc_2_1 = downsample_2_1<ColorTypeFilter_1616>;
481 proc_2_2 = downsample_2_2<ColorTypeFilter_1616>;
482 proc_2_3 = downsample_2_3<ColorTypeFilter_1616>;
483 proc_3_1 = downsample_3_1<ColorTypeFilter_1616>;
484 proc_3_2 = downsample_3_2<ColorTypeFilter_1616>;
485 proc_3_3 = downsample_3_3<ColorTypeFilter_1616>;
486 break;
487 case kA16_unorm_SkColorType:
488 proc_1_2 = downsample_1_2<ColorTypeFilter_16>;
489 proc_1_3 = downsample_1_3<ColorTypeFilter_16>;
490 proc_2_1 = downsample_2_1<ColorTypeFilter_16>;
491 proc_2_2 = downsample_2_2<ColorTypeFilter_16>;
492 proc_2_3 = downsample_2_3<ColorTypeFilter_16>;
493 proc_3_1 = downsample_3_1<ColorTypeFilter_16>;
494 proc_3_2 = downsample_3_2<ColorTypeFilter_16>;
495 proc_3_3 = downsample_3_3<ColorTypeFilter_16>;
496 break;
497 case kRGBA_1010102_SkColorType:
498 case kBGRA_1010102_SkColorType:
499 proc_1_2 = downsample_1_2<ColorTypeFilter_1010102>;
500 proc_1_3 = downsample_1_3<ColorTypeFilter_1010102>;
501 proc_2_1 = downsample_2_1<ColorTypeFilter_1010102>;
502 proc_2_2 = downsample_2_2<ColorTypeFilter_1010102>;
503 proc_2_3 = downsample_2_3<ColorTypeFilter_1010102>;
504 proc_3_1 = downsample_3_1<ColorTypeFilter_1010102>;
505 proc_3_2 = downsample_3_2<ColorTypeFilter_1010102>;
506 proc_3_3 = downsample_3_3<ColorTypeFilter_1010102>;
507 break;
508 case kA16_float_SkColorType:
509 proc_1_2 = downsample_1_2<ColorTypeFilter_Alpha_F16>;
510 proc_1_3 = downsample_1_3<ColorTypeFilter_Alpha_F16>;
511 proc_2_1 = downsample_2_1<ColorTypeFilter_Alpha_F16>;
512 proc_2_2 = downsample_2_2<ColorTypeFilter_Alpha_F16>;
513 proc_2_3 = downsample_2_3<ColorTypeFilter_Alpha_F16>;
514 proc_3_1 = downsample_3_1<ColorTypeFilter_Alpha_F16>;
515 proc_3_2 = downsample_3_2<ColorTypeFilter_Alpha_F16>;
516 proc_3_3 = downsample_3_3<ColorTypeFilter_Alpha_F16>;
517 break;
518 case kR16G16_float_SkColorType:
519 proc_1_2 = downsample_1_2<ColorTypeFilter_F16F16>;
520 proc_1_3 = downsample_1_3<ColorTypeFilter_F16F16>;
521 proc_2_1 = downsample_2_1<ColorTypeFilter_F16F16>;
522 proc_2_2 = downsample_2_2<ColorTypeFilter_F16F16>;
523 proc_2_3 = downsample_2_3<ColorTypeFilter_F16F16>;
524 proc_3_1 = downsample_3_1<ColorTypeFilter_F16F16>;
525 proc_3_2 = downsample_3_2<ColorTypeFilter_F16F16>;
526 proc_3_3 = downsample_3_3<ColorTypeFilter_F16F16>;
527 break;
528 case kR16G16B16A16_unorm_SkColorType:
529 proc_1_2 = downsample_1_2<ColorTypeFilter_16161616>;
530 proc_1_3 = downsample_1_3<ColorTypeFilter_16161616>;
531 proc_2_1 = downsample_2_1<ColorTypeFilter_16161616>;
532 proc_2_2 = downsample_2_2<ColorTypeFilter_16161616>;
533 proc_2_3 = downsample_2_3<ColorTypeFilter_16161616>;
534 proc_3_1 = downsample_3_1<ColorTypeFilter_16161616>;
535 proc_3_2 = downsample_3_2<ColorTypeFilter_16161616>;
536 proc_3_3 = downsample_3_3<ColorTypeFilter_16161616>;
537 break;
538
539 case kUnknown_SkColorType:
540 case kRGB_888x_SkColorType: // TODO: use 8888?
541 case kRGB_101010x_SkColorType: // TODO: use 1010102?
542 case kBGR_101010x_SkColorType: // TODO: use 1010102?
543 case kRGBA_F32_SkColorType:
544 return nullptr;
545 }
546
547 if (src.width() <= 1 && src.height() <= 1) {
548 return nullptr;
549 }
550 // whip through our loop to compute the exact size needed
551 size_t size = 0;
552 int countLevels = ComputeLevelCount(src.width(), src.height());
553 for (int currentMipLevel = countLevels; currentMipLevel >= 0; currentMipLevel--) {
554 SkISize mipSize = ComputeLevelSize(src.width(), src.height(), currentMipLevel);
555 size += SkColorTypeMinRowBytes(ct, mipSize.fWidth) * mipSize.fHeight;
556 }
557
558 size_t storageSize = SkMipmap::AllocLevelsSize(countLevels, size);
559 if (0 == storageSize) {
560 return nullptr;
561 }
562
563 SkMipmap* mipmap;
564 if (fact) {
565 SkDiscardableMemory* dm = fact(storageSize);
566 if (nullptr == dm) {
567 return nullptr;
568 }
569 mipmap = new SkMipmap(storageSize, dm);
570 } else {
571 mipmap = new SkMipmap(sk_malloc_throw(storageSize), storageSize);
572 }
573
574 // init
575 mipmap->fCS = sk_ref_sp(src.info().colorSpace());
576 mipmap->fCount = countLevels;
577 mipmap->fLevels = (Level*)mipmap->writable_data();
578 SkASSERT(mipmap->fLevels);
579
580 Level* levels = mipmap->fLevels;
581 uint8_t* baseAddr = (uint8_t*)&levels[countLevels];
582 uint8_t* addr = baseAddr;
583 int width = src.width();
584 int height = src.height();
585 uint32_t rowBytes;
586 SkPixmap srcPM(src);
587
588 // Depending on architecture and other factors, the pixel data alignment may need to be as
589 // large as 8 (for F16 pixels). See the comment on SkMipmap::Level.
590 SkASSERT(SkIsAlign8((uintptr_t)addr));
591
592 for (int i = 0; i < countLevels; ++i) {
593 FilterProc* proc;
594 if (height & 1) {
595 if (height == 1) { // src-height is 1
596 if (width & 1) { // src-width is 3
597 proc = proc_3_1;
598 } else { // src-width is 2
599 proc = proc_2_1;
600 }
601 } else { // src-height is 3
602 if (width & 1) {
603 if (width == 1) { // src-width is 1
604 proc = proc_1_3;
605 } else { // src-width is 3
606 proc = proc_3_3;
607 }
608 } else { // src-width is 2
609 proc = proc_2_3;
610 }
611 }
612 } else { // src-height is 2
613 if (width & 1) {
614 if (width == 1) { // src-width is 1
615 proc = proc_1_2;
616 } else { // src-width is 3
617 proc = proc_3_2;
618 }
619 } else { // src-width is 2
620 proc = proc_2_2;
621 }
622 }
623 width = std::max(1, width >> 1);
624 height = std::max(1, height >> 1);
625 rowBytes = SkToU32(SkColorTypeMinRowBytes(ct, width));
626
627 // We make the Info w/o any colorspace, since that storage is not under our control, and
628 // will not be deleted in a controlled fashion. When the caller is given the pixmap for
629 // a given level, we augment this pixmap with fCS (which we do manage).
630 new (&levels[i].fPixmap) SkPixmap(SkImageInfo::Make(width, height, ct, at), addr, rowBytes);
631 levels[i].fScale = SkSize::Make(SkIntToScalar(width) / src.width(),
632 SkIntToScalar(height) / src.height());
633
634 const SkPixmap& dstPM = levels[i].fPixmap;
635 if (computeContents) {
636 const void* srcBasePtr = srcPM.addr();
637 void* dstBasePtr = dstPM.writable_addr();
638
639 const size_t srcRB = srcPM.rowBytes();
640 for (int y = 0; y < height; y++) {
641 proc(dstBasePtr, srcBasePtr, srcRB, width);
642 srcBasePtr = (char*)srcBasePtr + srcRB * 2; // jump two rows
643 dstBasePtr = (char*)dstBasePtr + dstPM.rowBytes();
644 }
645 }
646 srcPM = dstPM;
647 addr += height * rowBytes;
648 }
649 SkASSERT(addr == baseAddr + size);
650
651 SkASSERT(mipmap->fLevels);
652 return mipmap;
653}
654
655int SkMipmap::ComputeLevelCount(int baseWidth, int baseHeight) {
656 if (baseWidth < 1 || baseHeight < 1) {
657 return 0;
658 }
659
660 // OpenGL's spec requires that each mipmap level have height/width equal to
661 // max(1, floor(original_height / 2^i)
662 // (or original_width) where i is the mipmap level.
663 // Continue scaling down until both axes are size 1.
664
665 const int largestAxis = std::max(baseWidth, baseHeight);
666 if (largestAxis < 2) {
667 // SkMipmap::Build requires a minimum size of 2.
668 return 0;
669 }
670 const int leadingZeros = SkCLZ(static_cast<uint32_t>(largestAxis));
671 // If the value 00011010 has 3 leading 0s then it has 5 significant bits
672 // (the bits which are not leading zeros)
673 const int significantBits = (sizeof(uint32_t) * 8) - leadingZeros;
674 // This is making the assumption that the size of a byte is 8 bits
675 // and that sizeof(uint32_t)'s implementation-defined behavior is 4.
676 int mipLevelCount = significantBits;
677
678 // SkMipmap does not include the base mip level.
679 // For example, it contains levels 1-x instead of 0-x.
680 // This is because the image used to create SkMipmap is the base level.
681 // So subtract 1 from the mip level count.
682 if (mipLevelCount > 0) {
683 --mipLevelCount;
684 }
685
686 return mipLevelCount;
687}
688
689SkISize SkMipmap::ComputeLevelSize(int baseWidth, int baseHeight, int level) {
690 if (baseWidth < 1 || baseHeight < 1) {
691 return SkISize::Make(0, 0);
692 }
693
694 int maxLevelCount = ComputeLevelCount(baseWidth, baseHeight);
695 if (level >= maxLevelCount || level < 0) {
696 return SkISize::Make(0, 0);
697 }
698 // OpenGL's spec requires that each mipmap level have height/width equal to
699 // max(1, floor(original_height / 2^i)
700 // (or original_width) where i is the mipmap level.
701
702 // SkMipmap does not include the base mip level.
703 // For example, it contains levels 1-x instead of 0-x.
704 // This is because the image used to create SkMipmap is the base level.
705 // So subtract 1 from the mip level to get the index stored by SkMipmap.
706 int width = std::max(1, baseWidth >> (level + 1));
707 int height = std::max(1, baseHeight >> (level + 1));
708
709 return SkISize::Make(width, height);
710}
711
712///////////////////////////////////////////////////////////////////////////////
713
714// Returns fractional level value. floor(level) is the index of the larger level.
715// < 0 means failure.
716float SkMipmap::ComputeLevel(SkSize scaleSize) {
717 SkASSERT(scaleSize.width() >= 0 && scaleSize.height() >= 0);
718
719#ifndef SK_SUPPORT_LEGACY_ANISOTROPIC_MIPMAP_SCALE
720 // Use the smallest scale to match the GPU impl.
721 const SkScalar scale = std::min(scaleSize.width(), scaleSize.height());
722#else
723 // Ideally we'd pick the smaller scale, to match Ganesh. But ignoring one of the
724 // scales can produce some atrocious results, so for now we use the geometric mean.
725 // (https://bugs.chromium.org/p/skia/issues/detail?id=4863)
726 const SkScalar scale = SkScalarSqrt(scaleSize.width() * scaleSize.height());
727#endif
728
729 if (scale >= SK_Scalar1 || scale <= 0 || !SkScalarIsFinite(scale)) {
730 return -1;
731 }
732
733 SkScalar L = -SkScalarLog2(scale);
734 if (!SkScalarIsFinite(L)) {
735 return -1;
736 }
737 SkASSERT(L >= 0);
738 return L;
739}
740
741bool SkMipmap::extractLevel(SkSize scaleSize, Level* levelPtr) const {
742 if (nullptr == fLevels) {
743 return false;
744 }
745
746 float L = ComputeLevel(scaleSize);
747 int level = SkScalarFloorToInt(L);
748 if (level <= 0) {
749 return false;
750 }
751
752 if (level > fCount) {
753 level = fCount;
754 }
755 if (levelPtr) {
756 *levelPtr = fLevels[level - 1];
757 // need to augment with our colorspace
758 levelPtr->fPixmap.setColorSpace(fCS);
759 }
760 return true;
761}
762
763bool SkMipmap::validForRootLevel(const SkImageInfo& root) const {
764 if (nullptr == fLevels) {
765 return false;
766 }
767
768 const SkISize dimension = root.dimensions();
769 if (dimension.width() <= 1 && dimension.height() <= 1) {
770 return false;
771 }
772
773 const SkPixmap& pm = fLevels[0].fPixmap;
774 if (pm. width() != std::max(1, dimension. width() >> 1) ||
775 pm.height() != std::max(1, dimension.height() >> 1)) {
776 return false;
777 }
778
779 for (int i = 0; i < this->countLevels(); ++i) {
780 const SkPixmap& pm = fLevels[0].fPixmap;
781 if (pm.colorType() != root.colorType() ||
782 pm.alphaType() != root.alphaType())
783 return false;
784 }
785 return true;
786}
787
788// Helper which extracts a pixmap from the src bitmap
789//
790SkMipmap* SkMipmap::Build(const SkBitmap& src, SkDiscardableFactoryProc fact) {
791 SkPixmap srcPixmap;
792 if (!src.peekPixels(&srcPixmap)) {
793 return nullptr;
794 }
795 return Build(srcPixmap, fact);
796}
797
798int SkMipmap::countLevels() const {
799 return fCount;
800}
801
802bool SkMipmap::getLevel(int index, Level* levelPtr) const {
803 if (nullptr == fLevels) {
804 return false;
805 }
806 if (index < 0) {
807 return false;
808 }
809 if (index > fCount - 1) {
810 return false;
811 }
812 if (levelPtr) {
813 *levelPtr = fLevels[index];
814 // need to augment with our colorspace
815 levelPtr->fPixmap.setColorSpace(fCS);
816 }
817 return true;
818}
819
820//////////////////////////////////////////////////////////////////////////////////////////////////
821
822#include "include/core/SkImageGenerator.h"
823#include "include/core/SkStream.h"
824#include "include/encode/SkPngEncoder.h"
825#include "src/core/SkReadBuffer.h"
826#include "src/core/SkWriteBuffer.h"
827
828static sk_sp<SkData> encode_to_data(const SkPixmap& pm) {
829 SkDynamicMemoryWStream stream;
830 if (SkPngEncoder::Encode(&stream, pm, SkPngEncoder::Options())) {
831 return stream.detachAsData();
832 }
833 return nullptr;
834}
835
836/* Format
837 count_levels:32
838 for each level, starting with the biggest (index 0 in our iterator)
839 encoded_size:32
840 encoded_data (padded)
841 */
842sk_sp<SkData> SkMipmap::serialize() const {
843 const int count = this->countLevels();
844
845 SkBinaryWriteBuffer buffer;
846 buffer.write32(count);
847 for (int i = 0; i < count; ++i) {
848 Level level;
849 if (this->getLevel(i, &level)) {
850 buffer.writeDataAsByteArray(encode_to_data(level.fPixmap).get());
851 } else {
852 return nullptr;
853 }
854 }
855 return buffer.snapshotAsData();
856}
857
858bool SkMipmap::Deserialize(SkMipmapBuilder* builder, const void* data, size_t size) {
859 SkReadBuffer buffer(data, size);
860
861 int count = buffer.read32();
862 if (builder->countLevels() != count) {
863 return false;
864 }
865 for (int i = 0; i < count; ++i) {
866 size_t size = buffer.read32();
867 const void* ptr = buffer.skip(size);
868 if (!ptr) {
869 return false;
870 }
871 auto gen = SkImageGenerator::MakeFromEncoded(
872 SkData::MakeWithProc(ptr, size, nullptr, nullptr));
873 if (!gen) {
874 return false;
875 }
876
877 SkPixmap pm = builder->level(i);
878 if (gen->getInfo().dimensions() != pm.dimensions()) {
879 return false;
880 }
881 if (!gen->getPixels(pm)) {
882 return false;
883 }
884 }
885 return buffer.isValid();
886}
887