1 /*
2 * Copyright 2010 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 "src/gpu/SkGr.h"
9
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColorFilter.h"
12 #include "include/core/SkData.h"
13 #include "include/core/SkPixelRef.h"
14 #include "include/effects/SkRuntimeEffect.h"
15 #include "include/gpu/GrRecordingContext.h"
16 #include "include/private/SkIDChangeListener.h"
17 #include "include/private/SkImageInfoPriv.h"
18 #include "include/private/SkTPin.h"
19 #include "include/private/SkTemplates.h"
20 #include "src/core/SkAutoMalloc.h"
21 #include "src/core/SkBlendModePriv.h"
22 #include "src/core/SkBlenderBase.h"
23 #include "src/core/SkColorFilterBase.h"
24 #include "src/core/SkColorSpacePriv.h"
25 #include "src/core/SkImagePriv.h"
26 #include "src/core/SkMaskFilterBase.h"
27 #include "src/core/SkMessageBus.h"
28 #include "src/core/SkMipmap.h"
29 #include "src/core/SkPaintPriv.h"
30 #include "src/core/SkResourceCache.h"
31 #include "src/core/SkRuntimeEffectPriv.h"
32 #include "src/core/SkTraceEvent.h"
33 #include "src/gpu/GrCaps.h"
34 #include "src/gpu/GrColorInfo.h"
35 #include "src/gpu/GrColorSpaceXform.h"
36 #include "src/gpu/GrGpuResourcePriv.h"
37 #include "src/gpu/GrPaint.h"
38 #include "src/gpu/GrProxyProvider.h"
39 #include "src/gpu/GrRecordingContextPriv.h"
40 #include "src/gpu/GrTextureProxy.h"
41 #include "src/gpu/GrXferProcessor.h"
42 #include "src/gpu/SkGr.h"
43 #include "src/gpu/effects/GrBicubicEffect.h"
44 #include "src/gpu/effects/GrBlendFragmentProcessor.h"
45 #include "src/gpu/effects/GrPorterDuffXferProcessor.h"
46 #include "src/gpu/effects/GrSkSLFP.h"
47 #include "src/gpu/effects/GrTextureEffect.h"
48 #include "src/image/SkImage_Base.h"
49 #include "src/shaders/SkShaderBase.h"
50
GrMakeKeyFromImageID(skgpu::UniqueKey * key,uint32_t imageID,const SkIRect & imageBounds)51 void GrMakeKeyFromImageID(skgpu::UniqueKey* key, uint32_t imageID, const SkIRect& imageBounds) {
52 SkASSERT(key);
53 SkASSERT(imageID);
54 SkASSERT(!imageBounds.isEmpty());
55 static const skgpu::UniqueKey::Domain kImageIDDomain = skgpu::UniqueKey::GenerateDomain();
56 skgpu::UniqueKey::Builder builder(key, kImageIDDomain, 5, "Image");
57 builder[0] = imageID;
58 builder[1] = imageBounds.fLeft;
59 builder[2] = imageBounds.fTop;
60 builder[3] = imageBounds.fRight;
61 builder[4] = imageBounds.fBottom;
62 }
63
64 ////////////////////////////////////////////////////////////////////////////////
65
GrMakeUniqueKeyInvalidationListener(skgpu::UniqueKey * key,uint32_t contextID)66 sk_sp<SkIDChangeListener> GrMakeUniqueKeyInvalidationListener(skgpu::UniqueKey* key,
67 uint32_t contextID) {
68 class Listener : public SkIDChangeListener {
69 public:
70 Listener(const skgpu::UniqueKey& key, uint32_t contextUniqueID)
71 : fMsg(key, contextUniqueID) {}
72
73 void changed() override {
74 SkMessageBus<skgpu::UniqueKeyInvalidatedMessage, uint32_t>::Post(fMsg);
75 }
76
77 private:
78 skgpu::UniqueKeyInvalidatedMessage fMsg;
79 };
80
81 auto listener = sk_make_sp<Listener>(*key, contextID);
82
83 // We stick a SkData on the key that calls invalidateListener in its destructor.
84 auto invalidateListener = [](const void* ptr, void* /*context*/) {
85 auto listener = reinterpret_cast<const sk_sp<Listener>*>(ptr);
86 (*listener)->markShouldDeregister();
87 delete listener;
88 };
89 auto data = SkData::MakeWithProc(new sk_sp<Listener>(listener),
90 sizeof(sk_sp<Listener>),
91 invalidateListener,
92 nullptr);
93 SkASSERT(!key->getCustomData());
94 key->setCustomData(std::move(data));
95 return std::move(listener);
96 }
97
GrCopyBaseMipMapToTextureProxy(GrRecordingContext * ctx,sk_sp<GrSurfaceProxy> baseProxy,GrSurfaceOrigin origin,SkBudgeted budgeted)98 sk_sp<GrSurfaceProxy> GrCopyBaseMipMapToTextureProxy(GrRecordingContext* ctx,
99 sk_sp<GrSurfaceProxy> baseProxy,
100 GrSurfaceOrigin origin,
101 SkBudgeted budgeted) {
102 SkASSERT(baseProxy);
103
104 // We don't allow this for promise proxies i.e. if they need mips they need to give them
105 // to us upfront.
106 if (baseProxy->isPromiseProxy()) {
107 return nullptr;
108 }
109 if (!ctx->priv().caps()->isFormatCopyable(baseProxy->backendFormat())) {
110 return nullptr;
111 }
112 auto copy = GrSurfaceProxy::Copy(ctx, std::move(baseProxy), origin, GrMipmapped::kYes,
113 SkBackingFit::kExact, budgeted);
114 if (!copy) {
115 return nullptr;
116 }
117 SkASSERT(copy->asTextureProxy());
118 return copy;
119 }
120
GrCopyBaseMipMapToView(GrRecordingContext * context,GrSurfaceProxyView src,SkBudgeted budgeted)121 GrSurfaceProxyView GrCopyBaseMipMapToView(GrRecordingContext* context,
122 GrSurfaceProxyView src,
123 SkBudgeted budgeted) {
124 auto origin = src.origin();
125 auto swizzle = src.swizzle();
126 auto proxy = src.refProxy();
127 return {GrCopyBaseMipMapToTextureProxy(context, proxy, origin, budgeted), origin, swizzle};
128 }
129
adjust_mipmapped(GrMipmapped mipmapped,const SkBitmap & bitmap,const GrCaps * caps)130 static GrMipmapped adjust_mipmapped(GrMipmapped mipmapped,
131 const SkBitmap& bitmap,
132 const GrCaps* caps) {
133 if (!caps->mipmapSupport() || bitmap.dimensions().area() <= 1) {
134 return GrMipmapped::kNo;
135 }
136 return mipmapped;
137 }
138
choose_bmp_texture_colortype(const GrCaps * caps,const SkBitmap & bitmap)139 static GrColorType choose_bmp_texture_colortype(const GrCaps* caps, const SkBitmap& bitmap) {
140 GrColorType ct = SkColorTypeToGrColorType(bitmap.info().colorType());
141 if (caps->getDefaultBackendFormat(ct, GrRenderable::kNo).isValid()) {
142 return ct;
143 }
144 return GrColorType::kRGBA_8888;
145 }
146
make_bmp_proxy(GrProxyProvider * proxyProvider,const SkBitmap & bitmap,GrColorType ct,GrMipmapped mipmapped,SkBackingFit fit,SkBudgeted budgeted)147 static sk_sp<GrTextureProxy> make_bmp_proxy(GrProxyProvider* proxyProvider,
148 const SkBitmap& bitmap,
149 GrColorType ct,
150 GrMipmapped mipmapped,
151 SkBackingFit fit,
152 SkBudgeted budgeted) {
153 SkBitmap bmpToUpload;
154 if (ct != SkColorTypeToGrColorType(bitmap.info().colorType())) {
155 SkColorType skCT = GrColorTypeToSkColorType(ct);
156 if (!bmpToUpload.tryAllocPixels(bitmap.info().makeColorType(skCT)) ||
157 !bitmap.readPixels(bmpToUpload.pixmap())) {
158 return {};
159 }
160 bmpToUpload.setImmutable();
161 } else {
162 bmpToUpload = bitmap;
163 }
164 auto proxy = proxyProvider->createProxyFromBitmap(bmpToUpload, mipmapped, fit, budgeted);
165 SkASSERT(!proxy || mipmapped == GrMipmapped::kNo || proxy->mipmapped() == GrMipmapped::kYes);
166 return proxy;
167 }
168
169 std::tuple<GrSurfaceProxyView, GrColorType>
GrMakeCachedBitmapProxyView(GrRecordingContext * rContext,const SkBitmap & bitmap,GrMipmapped mipmapped)170 GrMakeCachedBitmapProxyView(GrRecordingContext* rContext,
171 const SkBitmap& bitmap,
172 GrMipmapped mipmapped) {
173 if (!bitmap.peekPixels(nullptr)) {
174 return {};
175 }
176
177 GrProxyProvider* proxyProvider = rContext->priv().proxyProvider();
178 const GrCaps* caps = rContext->priv().caps();
179
180 skgpu::UniqueKey key;
181 SkIPoint origin = bitmap.pixelRefOrigin();
182 SkIRect subset = SkIRect::MakePtSize(origin, bitmap.dimensions());
183 GrMakeKeyFromImageID(&key, bitmap.pixelRef()->getGenerationID(), subset);
184
185 mipmapped = adjust_mipmapped(mipmapped, bitmap, caps);
186 GrColorType ct = choose_bmp_texture_colortype(caps, bitmap);
187
188 auto installKey = [&](GrTextureProxy* proxy) {
189 auto listener = GrMakeUniqueKeyInvalidationListener(&key, proxyProvider->contextID());
190 bitmap.pixelRef()->addGenIDChangeListener(std::move(listener));
191 proxyProvider->assignUniqueKeyToProxy(key, proxy);
192 };
193
194 sk_sp<GrTextureProxy> proxy = proxyProvider->findOrCreateProxyByUniqueKey(key);
195 if (!proxy) {
196 proxy = make_bmp_proxy(proxyProvider,
197 bitmap,
198 ct,
199 mipmapped,
200 SkBackingFit::kExact,
201 SkBudgeted::kYes);
202 if (!proxy) {
203 return {};
204 }
205 SkASSERT(mipmapped == GrMipmapped::kNo || proxy->mipmapped() == GrMipmapped::kYes);
206 installKey(proxy.get());
207 }
208
209 skgpu::Swizzle swizzle = caps->getReadSwizzle(proxy->backendFormat(), ct);
210 if (mipmapped == GrMipmapped::kNo || proxy->mipmapped() == GrMipmapped::kYes) {
211 return {{std::move(proxy), kTopLeft_GrSurfaceOrigin, swizzle}, ct};
212 }
213
214 // We need a mipped proxy, but we found a proxy earlier that wasn't mipped. Thus we generate
215 // a new mipped surface and copy the original proxy into the base layer. We will then let
216 // the gpu generate the rest of the mips.
217 auto mippedProxy = GrCopyBaseMipMapToTextureProxy(rContext, proxy, kTopLeft_GrSurfaceOrigin);
218 if (!mippedProxy) {
219 // We failed to make a mipped proxy with the base copied into it. This could have
220 // been from failure to make the proxy or failure to do the copy. Thus we will fall
221 // back to just using the non mipped proxy; See skbug.com/7094.
222 return {{std::move(proxy), kTopLeft_GrSurfaceOrigin, swizzle}, ct};
223 }
224 // In this case we are stealing the key from the original proxy which should only happen
225 // when we have just generated mipmaps for an originally unmipped proxy/texture. This
226 // means that all future uses of the key will access the mipmapped version. The texture
227 // backing the unmipped version will remain in the resource cache until the last texture
228 // proxy referencing it is deleted at which time it too will be deleted or recycled.
229 SkASSERT(proxy->getUniqueKey() == key);
230 proxyProvider->removeUniqueKeyFromProxy(proxy.get());
231 installKey(mippedProxy->asTextureProxy());
232 return {{std::move(mippedProxy), kTopLeft_GrSurfaceOrigin, swizzle}, ct};
233 }
234
235 std::tuple<GrSurfaceProxyView, GrColorType>
GrMakeUncachedBitmapProxyView(GrRecordingContext * rContext,const SkBitmap & bitmap,GrMipmapped mipmapped,SkBackingFit fit,SkBudgeted budgeted)236 GrMakeUncachedBitmapProxyView(GrRecordingContext* rContext,
237 const SkBitmap& bitmap,
238 GrMipmapped mipmapped,
239 SkBackingFit fit,
240 SkBudgeted budgeted) {
241 GrProxyProvider* proxyProvider = rContext->priv().proxyProvider();
242 const GrCaps* caps = rContext->priv().caps();
243
244 mipmapped = adjust_mipmapped(mipmapped, bitmap, caps);
245 GrColorType ct = choose_bmp_texture_colortype(caps, bitmap);
246
247 if (auto proxy = make_bmp_proxy(proxyProvider, bitmap, ct, mipmapped, fit, budgeted)) {
248 skgpu::Swizzle swizzle = caps->getReadSwizzle(proxy->backendFormat(), ct);
249 SkASSERT(mipmapped == GrMipmapped::kNo || proxy->mipmapped() == GrMipmapped::kYes);
250 return {{std::move(proxy), kTopLeft_GrSurfaceOrigin, swizzle}, ct};
251 }
252 return {};
253 }
254 ///////////////////////////////////////////////////////////////////////////////
255
SkColorToPMColor4f(SkColor c,const GrColorInfo & colorInfo)256 SkPMColor4f SkColorToPMColor4f(SkColor c, const GrColorInfo& colorInfo) {
257 SkColor4f color = SkColor4f::FromColor(c);
258 if (auto* xform = colorInfo.colorSpaceXformFromSRGB()) {
259 color = xform->apply(color);
260 }
261 return color.premul();
262 }
263
SkColor4fPrepForDst(SkColor4f color,const GrColorInfo & colorInfo)264 SkColor4f SkColor4fPrepForDst(SkColor4f color, const GrColorInfo& colorInfo) {
265 if (auto* xform = colorInfo.colorSpaceXformFromSRGB()) {
266 color = xform->apply(color);
267 }
268 return color;
269 }
270
271 ///////////////////////////////////////////////////////////////////////////////
272
blender_requires_shader(const SkBlender * blender)273 static inline bool blender_requires_shader(const SkBlender* blender) {
274 SkASSERT(blender);
275 std::optional<SkBlendMode> mode = as_BB(blender)->asBlendMode();
276 return !mode.has_value() || *mode != SkBlendMode::kDst;
277 }
278
279 #ifndef SK_IGNORE_GPU_DITHER
dither_range_for_config(GrColorType dstColorType)280 static inline float dither_range_for_config(GrColorType dstColorType) {
281 // We use 1 / (2^bitdepth-1) as the range since each channel can hold 2^bitdepth values
282 switch (dstColorType) {
283 // 4 bit
284 case GrColorType::kABGR_4444:
285 case GrColorType::kARGB_4444:
286 case GrColorType::kBGRA_4444:
287 return 1 / 15.f;
288 // 6 bit
289 case GrColorType::kBGR_565:
290 return 1 / 63.f;
291 // 8 bit
292 case GrColorType::kUnknown:
293 case GrColorType::kAlpha_8:
294 case GrColorType::kAlpha_8xxx:
295 case GrColorType::kGray_8:
296 case GrColorType::kGrayAlpha_88:
297 case GrColorType::kGray_8xxx:
298 case GrColorType::kR_8:
299 case GrColorType::kR_8xxx:
300 case GrColorType::kRG_88:
301 case GrColorType::kRGB_888:
302 case GrColorType::kRGB_888x:
303 case GrColorType::kRGBA_8888:
304 case GrColorType::kRGBA_8888_SRGB:
305 case GrColorType::kBGRA_8888:
306 return 1 / 255.f;
307 // 10 bit
308 case GrColorType::kRGBA_1010102:
309 case GrColorType::kBGRA_1010102:
310 return 1 / 1023.f;
311 // 16 bit
312 case GrColorType::kAlpha_16:
313 case GrColorType::kR_16:
314 case GrColorType::kRG_1616:
315 case GrColorType::kRGBA_16161616:
316 return 1 / 32767.f;
317 // Half
318 case GrColorType::kAlpha_F16:
319 case GrColorType::kGray_F16:
320 case GrColorType::kR_F16:
321 case GrColorType::kRG_F16:
322 case GrColorType::kRGBA_F16:
323 case GrColorType::kRGBA_F16_Clamped:
324 // Float
325 case GrColorType::kAlpha_F32xxx:
326 case GrColorType::kRGBA_F32:
327 return 0.f; // no dithering
328 }
329 SkUNREACHABLE;
330 }
331
make_dither_lut()332 static SkBitmap make_dither_lut() {
333 static constexpr struct DitherTable {
334 constexpr DitherTable() : data() {
335 for (int x = 0; x < 8; ++x) {
336 for (int y = 0; y < 8; ++y) {
337 // The computation of 'm' and 'value' is lifted from CPU backend.
338 unsigned int m = (y & 1) << 5 | (x & 1) << 4 |
339 (y & 2) << 2 | (x & 2) << 1 |
340 (y & 4) >> 1 | (x & 4) >> 2;
341 float value = float(m) * 1.0 / 64.0 - 63.0 / 128.0;
342 // Bias by 0.5 to be in 0..1, mul by 255 and round to nearest int to make byte.
343 data[y * 8 + x] = (uint8_t)((value + 0.5) * 255.f + 0.5f);
344 }
345 }
346 }
347 uint8_t data[64];
348 } gTable;
349 SkBitmap bmp;
350 bmp.setInfo(SkImageInfo::MakeA8(8, 8));
351 bmp.setPixels(const_cast<uint8_t*>(gTable.data));
352 bmp.setImmutable();
353 return bmp;
354 }
355
make_dither_effect(GrRecordingContext * rContext,std::unique_ptr<GrFragmentProcessor> inputFP,float range,const GrCaps * caps)356 static std::unique_ptr<GrFragmentProcessor> make_dither_effect(
357 GrRecordingContext* rContext,
358 std::unique_ptr<GrFragmentProcessor> inputFP,
359 float range,
360 const GrCaps* caps) {
361 if (range == 0 || inputFP == nullptr) {
362 return inputFP;
363 }
364
365 if (caps->avoidDithering()) {
366 return inputFP;
367 }
368
369 // We used to use integer math on sk_FragCoord, when supported, and a fallback using floating
370 // point (on a 4x4 rather than 8x8 grid). Now we precompute a 8x8 table in a texture because
371 // it was shown to be significantly faster on several devices. Test was done with the following
372 // running in viewer with the stats layer enabled and looking at total frame time:
373 // SkRandom r;
374 // for (int i = 0; i < N; ++i) {
375 // SkColor c[2] = {r.nextU(), r.nextU()};
376 // SkPoint pts[2] = {{r.nextRangeScalar(0, 500), r.nextRangeScalar(0, 500)},
377 // {r.nextRangeScalar(0, 500), r.nextRangeScalar(0, 500)}};
378 // SkPaint p;
379 // p.setDither(true);
380 // p.setShader(SkGradientShader::MakeLinear(pts, c, nullptr, 2, SkTileMode::kRepeat));
381 // canvas->drawPaint(p);
382 // }
383 // Device GPU N no dither int math dither table dither
384 // Linux desktop QuadroP1000 5000 304ms 400ms (1.31x) 383ms (1.26x)
385 // TecnoSpark3Pro PowerVRGE8320 200 299ms 820ms (2.74x) 592ms (1.98x)
386 // Pixel 4 Adreno640 500 110ms 221ms (2.01x) 214ms (1.95x)
387 // Galaxy S20 FE Mali-G77 MP11 600 165ms 360ms (2.18x) 260ms (1.58x)
388 static const SkBitmap gLUT = make_dither_lut();
389 auto [tex, ct] = GrMakeCachedBitmapProxyView(rContext, gLUT, GrMipmapped::kNo);
390 if (!tex) {
391 return inputFP;
392 }
393 SkASSERT(ct == GrColorType::kAlpha_8);
394 GrSamplerState sampler(GrSamplerState::WrapMode::kRepeat, SkFilterMode::kNearest);
395 auto te = GrTextureEffect::Make(
396 std::move(tex), kPremul_SkAlphaType, SkMatrix::I(), sampler, *caps);
397 static auto effect = SkMakeRuntimeEffect(SkRuntimeEffect::MakeForShader, R"(
398 uniform half range;
399 uniform shader table;
400 half4 main(float2 xy, half4 color) {
401 half value = table.eval(sk_FragCoord.xy).a - 0.5; // undo the bias in the table
402 // For each color channel, add the random offset to the channel value and then clamp
403 // between 0 and alpha to keep the color premultiplied.
404 return half4(clamp(color.rgb + value * range, 0.0, color.a), color.a);
405 }
406 )", SkRuntimeEffectPriv::ES3Options());
407 return GrSkSLFP::Make(effect,
408 "Dither",
409 std::move(inputFP),
410 GrSkSLFP::OptFlags::kPreservesOpaqueInput,
411 "range",
412 range,
413 "table",
414 std::move(te));
415 }
416 #endif
417
skpaint_to_grpaint_impl(GrRecordingContext * context,const GrColorInfo & dstColorInfo,const SkPaint & skPaint,const SkMatrixProvider & matrixProvider,std::optional<std::unique_ptr<GrFragmentProcessor>> shaderFP,SkBlender * primColorBlender,GrPaint * grPaint)418 static inline bool skpaint_to_grpaint_impl(
419 GrRecordingContext* context,
420 const GrColorInfo& dstColorInfo,
421 const SkPaint& skPaint,
422 const SkMatrixProvider& matrixProvider,
423 std::optional<std::unique_ptr<GrFragmentProcessor>> shaderFP,
424 SkBlender* primColorBlender,
425 GrPaint* grPaint) {
426 // Convert SkPaint color to 4f format in the destination color space
427 SkColor4f origColor = SkColor4fPrepForDst(skPaint.getColor4f(), dstColorInfo);
428
429 GrFPArgs fpArgs(context, matrixProvider, &dstColorInfo);
430
431 // Setup the initial color considering the shader, the SkPaint color, and the presence or not
432 // of per-vertex colors.
433 std::unique_ptr<GrFragmentProcessor> paintFP;
434 const bool gpProvidesShader = shaderFP.has_value() && !*shaderFP;
435 if (!primColorBlender || blender_requires_shader(primColorBlender)) {
436 if (shaderFP.has_value()) {
437 paintFP = std::move(*shaderFP);
438 } else {
439 if (const SkShaderBase* shader = as_SB(skPaint.getShader())) {
440 paintFP = shader->asFragmentProcessor(fpArgs);
441 if (paintFP == nullptr) {
442 return false;
443 }
444 }
445 }
446 }
447
448 // Set this in below cases if the output of the shader/paint-color/paint-alpha/primXfermode is
449 // a known constant value. In that case we can simply apply a color filter during this
450 // conversion without converting the color filter to a GrFragmentProcessor.
451 bool applyColorFilterToPaintColor = false;
452 if (paintFP) {
453 if (primColorBlender) {
454 // There is a blend between the primitive color and the shader color. The shader sees
455 // the opaque paint color. The shader's output is blended using the provided mode by
456 // the primitive color. The blended color is then modulated by the paint's alpha.
457
458 // The geometry processor will insert the primitive color to start the color chain, so
459 // the GrPaint color will be ignored.
460
461 SkPMColor4f shaderInput = origColor.makeOpaque().premul();
462 paintFP = GrFragmentProcessor::OverrideInput(std::move(paintFP), shaderInput);
463 paintFP = as_BB(primColorBlender)->asFragmentProcessor(std::move(paintFP),
464 /*dstFP=*/nullptr,
465 fpArgs);
466
467 // We can ignore origColor here - alpha is unchanged by gamma
468 float paintAlpha = skPaint.getColor4f().fA;
469 if (1.0f != paintAlpha) {
470 // No gamut conversion - paintAlpha is a (linear) alpha value, splatted to all
471 // color channels. It's value should be treated as the same in ANY color space.
472 paintFP = GrFragmentProcessor::ModulateRGBA(
473 std::move(paintFP), {paintAlpha, paintAlpha, paintAlpha, paintAlpha});
474 }
475 } else {
476 float paintAlpha = skPaint.getColor4f().fA;
477 if (paintAlpha != 1.0f) {
478 // This invokes the shader's FP tree with an opaque version of the paint color,
479 // then multiplies the final result by the incoming (paint) alpha.
480 // We're actually putting the *unpremul* paint color on the GrPaint. This is okay,
481 // because the shader is supposed to see the original (opaque) RGB from the paint.
482 // ApplyPaintAlpha then creates a valid premul color by applying the paint alpha.
483 // Think of this as equivalent to (but faster than) putting origColor.premul() on
484 // the GrPaint, and ApplyPaintAlpha unpremuling it before passing it to the child.
485 paintFP = GrFragmentProcessor::ApplyPaintAlpha(std::move(paintFP));
486 grPaint->setColor4f({origColor.fR, origColor.fG, origColor.fB, origColor.fA});
487 } else {
488 // paintFP will ignore its input color, so we must disable coverage-as-alpha.
489 // TODO(skbug:11942): The alternative would be to always use ApplyPaintAlpha, but
490 // we'd need to measure the cost of that shader math against the CAA benefit.
491 paintFP = GrFragmentProcessor::DisableCoverageAsAlpha(std::move(paintFP));
492 grPaint->setColor4f(origColor.premul());
493 }
494 }
495 } else {
496 if (primColorBlender) {
497 // The primitive itself has color (e.g. interpolated vertex color) and this is what
498 // the GP will output. Thus, we must get the paint color in separately below as a color
499 // FP. This could be made more efficient if the relevant GPs used GrPaint color and
500 // took the SkBlender to apply with primitive color. As it stands changing the SkPaint
501 // color will break batches.
502 grPaint->setColor4f(SK_PMColor4fWHITE); // won't be used.
503 if (blender_requires_shader(primColorBlender)) {
504 paintFP = GrFragmentProcessor::MakeColor(origColor.makeOpaque().premul());
505 paintFP = as_BB(primColorBlender)->asFragmentProcessor(std::move(paintFP),
506 /*dstFP=*/nullptr,
507 fpArgs);
508 }
509
510 // The paint's *alpha* is applied after the paint/primitive color blend:
511 // We can ignore origColor here - alpha is unchanged by gamma
512 float paintAlpha = skPaint.getColor4f().fA;
513 if (paintAlpha != 1.0f) {
514 // No gamut conversion - paintAlpha is a (linear) alpha value, splatted to all
515 // color channels. It's value should be treated as the same in ANY color space.
516 paintFP = GrFragmentProcessor::ModulateRGBA(
517 std::move(paintFP), {paintAlpha, paintAlpha, paintAlpha, paintAlpha});
518 }
519 } else {
520 // No shader, no primitive color.
521 grPaint->setColor4f(origColor.premul());
522 // We can do this if there isn't a GP that is acting as the shader.
523 applyColorFilterToPaintColor = !gpProvidesShader;
524 }
525 }
526
527 SkColorFilter* colorFilter = skPaint.getColorFilter();
528 if (colorFilter) {
529 if (applyColorFilterToPaintColor) {
530 SkColorSpace* dstCS = dstColorInfo.colorSpace();
531 grPaint->setColor4f(colorFilter->filterColor4f(origColor, dstCS, dstCS).premul());
532 } else {
533 auto [success, fp] = as_CFB(colorFilter)->asFragmentProcessor(std::move(paintFP),
534 context, dstColorInfo);
535 if (!success) {
536 return false;
537 }
538 paintFP = std::move(fp);
539 }
540 }
541
542 SkMaskFilterBase* maskFilter = as_MFB(skPaint.getMaskFilter());
543 if (maskFilter) {
544 if (auto mfFP = maskFilter->asFragmentProcessor(fpArgs)) {
545 grPaint->setCoverageFragmentProcessor(std::move(mfFP));
546 }
547 }
548
549 #ifndef SK_IGNORE_GPU_DITHER
550 GrColorType ct = dstColorInfo.colorType();
551 if (SkPaintPriv::ShouldDither(skPaint, GrColorTypeToSkColorType(ct)) && paintFP != nullptr) {
552 float ditherRange = dither_range_for_config(ct);
553 paintFP = make_dither_effect(
554 context, std::move(paintFP), ditherRange, context->priv().caps());
555 }
556 #endif
557
558 // Note that for the final blend onto the canvas, we should prefer to use the GrXferProcessor
559 // instead of a SkBlendModeBlender to perform the blend. The Xfer processor is able to perform
560 // coefficient-based blends directly, without readback. This will be much more efficient.
561 if (auto bm = skPaint.asBlendMode()) {
562 // When the xfermode is null on the SkPaint (meaning kSrcOver) we need the XPFactory field
563 // on the GrPaint to also be null (also kSrcOver).
564 SkASSERT(!grPaint->getXPFactory());
565 if (bm.value() != SkBlendMode::kSrcOver) {
566 grPaint->setXPFactory(SkBlendMode_AsXPFactory(bm.value()));
567 }
568 } else {
569 // Apply a custom blend against the surface color, and force the XP to kSrc so that the
570 // computed result is applied directly to the canvas while still honoring the alpha.
571 paintFP = as_BB(skPaint.getBlender())->asFragmentProcessor(
572 std::move(paintFP),
573 GrFragmentProcessor::SurfaceColor(),
574 fpArgs);
575 grPaint->setXPFactory(SkBlendMode_AsXPFactory(SkBlendMode::kSrc));
576 }
577
578 if (GrColorTypeClampType(dstColorInfo.colorType()) == GrClampType::kManual) {
579 if (paintFP != nullptr) {
580 paintFP = GrFragmentProcessor::ClampOutput(std::move(paintFP));
581 } else {
582 auto color = grPaint->getColor4f();
583 grPaint->setColor4f({SkTPin(color.fR, 0.f, 1.f),
584 SkTPin(color.fG, 0.f, 1.f),
585 SkTPin(color.fB, 0.f, 1.f),
586 SkTPin(color.fA, 0.f, 1.f)});
587 }
588 }
589
590 if (paintFP) {
591 grPaint->setColorFragmentProcessor(std::move(paintFP));
592 }
593
594 return true;
595 }
596
SkPaintToGrPaint(GrRecordingContext * context,const GrColorInfo & dstColorInfo,const SkPaint & skPaint,const SkMatrixProvider & matrixProvider,GrPaint * grPaint)597 bool SkPaintToGrPaint(GrRecordingContext* context,
598 const GrColorInfo& dstColorInfo,
599 const SkPaint& skPaint,
600 const SkMatrixProvider& matrixProvider,
601 GrPaint* grPaint) {
602 return skpaint_to_grpaint_impl(context,
603 dstColorInfo,
604 skPaint,
605 matrixProvider,
606 /*shaderFP=*/std::nullopt,
607 /*primColorBlender=*/nullptr,
608 grPaint);
609 }
610
611 /** Replaces the SkShader (if any) on skPaint with the passed in GrFragmentProcessor. */
SkPaintToGrPaintReplaceShader(GrRecordingContext * context,const GrColorInfo & dstColorInfo,const SkPaint & skPaint,const SkMatrixProvider & matrixProvider,std::unique_ptr<GrFragmentProcessor> shaderFP,GrPaint * grPaint)612 bool SkPaintToGrPaintReplaceShader(GrRecordingContext* context,
613 const GrColorInfo& dstColorInfo,
614 const SkPaint& skPaint,
615 const SkMatrixProvider& matrixProvider,
616 std::unique_ptr<GrFragmentProcessor> shaderFP,
617 GrPaint* grPaint) {
618 return skpaint_to_grpaint_impl(context,
619 dstColorInfo,
620 skPaint,
621 matrixProvider,
622 std::move(shaderFP),
623 /*primColorBlender=*/nullptr,
624 grPaint);
625 }
626
627 /** Blends the SkPaint's shader (or color if no shader) with a per-primitive color which must
628 be setup as a vertex attribute using the specified SkBlender. */
SkPaintToGrPaintWithBlend(GrRecordingContext * context,const GrColorInfo & dstColorInfo,const SkPaint & skPaint,const SkMatrixProvider & matrixProvider,SkBlender * primColorBlender,GrPaint * grPaint)629 bool SkPaintToGrPaintWithBlend(GrRecordingContext* context,
630 const GrColorInfo& dstColorInfo,
631 const SkPaint& skPaint,
632 const SkMatrixProvider& matrixProvider,
633 SkBlender* primColorBlender,
634 GrPaint* grPaint) {
635 return skpaint_to_grpaint_impl(context,
636 dstColorInfo,
637 skPaint,
638 matrixProvider,
639 /*shaderFP=*/std::nullopt,
640 primColorBlender,
641 grPaint);
642 }
643