1 /*
2 * Copyright 2012 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 "GrSWMaskHelper.h"
9
10 #include "GrPipelineBuilder.h"
11 #include "GrDrawTargetCaps.h"
12 #include "GrGpu.h"
13
14 #include "SkData.h"
15 #include "SkDistanceFieldGen.h"
16 #include "SkStrokeRec.h"
17
18 // TODO: try to remove this #include
19 #include "GrContext.h"
20
21 namespace {
22
23 /*
24 * Convert a boolean operation into a transfer mode code
25 */
op_to_mode(SkRegion::Op op)26 SkXfermode::Mode op_to_mode(SkRegion::Op op) {
27
28 static const SkXfermode::Mode modeMap[] = {
29 SkXfermode::kDstOut_Mode, // kDifference_Op
30 SkXfermode::kModulate_Mode, // kIntersect_Op
31 SkXfermode::kSrcOver_Mode, // kUnion_Op
32 SkXfermode::kXor_Mode, // kXOR_Op
33 SkXfermode::kClear_Mode, // kReverseDifference_Op
34 SkXfermode::kSrc_Mode, // kReplace_Op
35 };
36
37 return modeMap[op];
38 }
39
fmt_to_config(SkTextureCompressor::Format fmt)40 static inline GrPixelConfig fmt_to_config(SkTextureCompressor::Format fmt) {
41
42 GrPixelConfig config;
43 switch (fmt) {
44 case SkTextureCompressor::kLATC_Format:
45 config = kLATC_GrPixelConfig;
46 break;
47
48 case SkTextureCompressor::kR11_EAC_Format:
49 config = kR11_EAC_GrPixelConfig;
50 break;
51
52 case SkTextureCompressor::kASTC_12x12_Format:
53 config = kASTC_12x12_GrPixelConfig;
54 break;
55
56 case SkTextureCompressor::kETC1_Format:
57 config = kETC1_GrPixelConfig;
58 break;
59
60 default:
61 SkDEBUGFAIL("No GrPixelConfig for compression format!");
62 // Best guess
63 config = kAlpha_8_GrPixelConfig;
64 break;
65 }
66
67 return config;
68 }
69
choose_compressed_fmt(const GrDrawTargetCaps * caps,SkTextureCompressor::Format * fmt)70 static bool choose_compressed_fmt(const GrDrawTargetCaps* caps,
71 SkTextureCompressor::Format *fmt) {
72 if (NULL == fmt) {
73 return false;
74 }
75
76 // We can't use scratch textures without the ability to update
77 // compressed textures...
78 if (!(caps->compressedTexSubImageSupport())) {
79 return false;
80 }
81
82 // Figure out what our preferred texture type is. If ASTC is available, that always
83 // gives the biggest win. Otherwise, in terms of compression speed and accuracy,
84 // LATC has a slight edge over R11 EAC.
85 if (caps->isConfigTexturable(kASTC_12x12_GrPixelConfig)) {
86 *fmt = SkTextureCompressor::kASTC_12x12_Format;
87 return true;
88 } else if (caps->isConfigTexturable(kLATC_GrPixelConfig)) {
89 *fmt = SkTextureCompressor::kLATC_Format;
90 return true;
91 } else if (caps->isConfigTexturable(kR11_EAC_GrPixelConfig)) {
92 *fmt = SkTextureCompressor::kR11_EAC_Format;
93 return true;
94 }
95
96 return false;
97 }
98
99 }
100
101 /**
102 * Draw a single rect element of the clip stack into the accumulation bitmap
103 */
draw(const SkRect & rect,SkRegion::Op op,bool antiAlias,uint8_t alpha)104 void GrSWMaskHelper::draw(const SkRect& rect, SkRegion::Op op,
105 bool antiAlias, uint8_t alpha) {
106 SkPaint paint;
107
108 SkXfermode* mode = SkXfermode::Create(op_to_mode(op));
109
110 SkASSERT(kNone_CompressionMode == fCompressionMode);
111
112 paint.setXfermode(mode);
113 paint.setAntiAlias(antiAlias);
114 paint.setColor(SkColorSetARGB(alpha, alpha, alpha, alpha));
115
116 fDraw.drawRect(rect, paint);
117
118 SkSafeUnref(mode);
119 }
120
121 /**
122 * Draw a single path element of the clip stack into the accumulation bitmap
123 */
draw(const SkPath & path,const SkStrokeRec & stroke,SkRegion::Op op,bool antiAlias,uint8_t alpha)124 void GrSWMaskHelper::draw(const SkPath& path, const SkStrokeRec& stroke, SkRegion::Op op,
125 bool antiAlias, uint8_t alpha) {
126
127 SkPaint paint;
128 if (stroke.isHairlineStyle()) {
129 paint.setStyle(SkPaint::kStroke_Style);
130 paint.setStrokeWidth(SK_Scalar1);
131 } else {
132 if (stroke.isFillStyle()) {
133 paint.setStyle(SkPaint::kFill_Style);
134 } else {
135 paint.setStyle(SkPaint::kStroke_Style);
136 paint.setStrokeJoin(stroke.getJoin());
137 paint.setStrokeCap(stroke.getCap());
138 paint.setStrokeWidth(stroke.getWidth());
139 }
140 }
141 paint.setAntiAlias(antiAlias);
142
143 SkTBlitterAllocator allocator;
144 SkBlitter* blitter = NULL;
145 if (kBlitter_CompressionMode == fCompressionMode) {
146 SkASSERT(fCompressedBuffer.get());
147 blitter = SkTextureCompressor::CreateBlitterForFormat(
148 fBM.width(), fBM.height(), fCompressedBuffer.get(), &allocator, fCompressedFormat);
149 }
150
151 if (SkRegion::kReplace_Op == op && 0xFF == alpha) {
152 SkASSERT(0xFF == paint.getAlpha());
153 fDraw.drawPathCoverage(path, paint, blitter);
154 } else {
155 paint.setXfermodeMode(op_to_mode(op));
156 paint.setColor(SkColorSetARGB(alpha, alpha, alpha, alpha));
157 fDraw.drawPath(path, paint, blitter);
158 }
159 }
160
init(const SkIRect & resultBounds,const SkMatrix * matrix,bool allowCompression)161 bool GrSWMaskHelper::init(const SkIRect& resultBounds,
162 const SkMatrix* matrix,
163 bool allowCompression) {
164 if (matrix) {
165 fMatrix = *matrix;
166 } else {
167 fMatrix.setIdentity();
168 }
169
170 // Now translate so the bound's UL corner is at the origin
171 fMatrix.postTranslate(-resultBounds.fLeft * SK_Scalar1,
172 -resultBounds.fTop * SK_Scalar1);
173 SkIRect bounds = SkIRect::MakeWH(resultBounds.width(),
174 resultBounds.height());
175
176 if (allowCompression &&
177 fContext->getOptions().fDrawPathToCompressedTexture &&
178 choose_compressed_fmt(fContext->getGpu()->caps(), &fCompressedFormat)) {
179 fCompressionMode = kCompress_CompressionMode;
180 }
181
182 // Make sure that the width is a multiple of the desired block dimensions
183 // to allow for specialized SIMD instructions that compress multiple blocks at a time.
184 int cmpWidth = bounds.fRight;
185 int cmpHeight = bounds.fBottom;
186 if (kCompress_CompressionMode == fCompressionMode) {
187 int dimX, dimY;
188 SkTextureCompressor::GetBlockDimensions(fCompressedFormat, &dimX, &dimY);
189 cmpWidth = dimX * ((cmpWidth + (dimX - 1)) / dimX);
190 cmpHeight = dimY * ((cmpHeight + (dimY - 1)) / dimY);
191
192 // Can we create a blitter?
193 if (SkTextureCompressor::ExistsBlitterForFormat(fCompressedFormat)) {
194 int cmpSz = SkTextureCompressor::GetCompressedDataSize(
195 fCompressedFormat, cmpWidth, cmpHeight);
196
197 SkASSERT(cmpSz > 0);
198 SkASSERT(NULL == fCompressedBuffer.get());
199 fCompressedBuffer.reset(cmpSz);
200 fCompressionMode = kBlitter_CompressionMode;
201 }
202 }
203
204 // If we don't have a custom blitter, then we either need a bitmap to compress
205 // from or a bitmap that we're going to use as a texture. In any case, we should
206 // allocate the pixels for a bitmap
207 const SkImageInfo bmImageInfo = SkImageInfo::MakeA8(cmpWidth, cmpHeight);
208 if (kBlitter_CompressionMode != fCompressionMode) {
209 if (!fBM.tryAllocPixels(bmImageInfo)) {
210 return false;
211 }
212
213 sk_bzero(fBM.getPixels(), fBM.getSafeSize());
214 } else {
215 // Otherwise, we just need to remember how big the buffer is...
216 fBM.setInfo(bmImageInfo);
217 }
218
219 sk_bzero(&fDraw, sizeof(fDraw));
220
221 fRasterClip.setRect(bounds);
222 fDraw.fRC = &fRasterClip;
223 fDraw.fClip = &fRasterClip.bwRgn();
224 fDraw.fMatrix = &fMatrix;
225 fDraw.fBitmap = &fBM;
226 return true;
227 }
228
229 /**
230 * Get a texture (from the texture cache) of the correct size & format.
231 */
createTexture()232 GrTexture* GrSWMaskHelper::createTexture() {
233 GrSurfaceDesc desc;
234 desc.fWidth = fBM.width();
235 desc.fHeight = fBM.height();
236 desc.fConfig = kAlpha_8_GrPixelConfig;
237
238 if (kNone_CompressionMode != fCompressionMode) {
239
240 #ifdef SK_DEBUG
241 int dimX, dimY;
242 SkTextureCompressor::GetBlockDimensions(fCompressedFormat, &dimX, &dimY);
243 SkASSERT((desc.fWidth % dimX) == 0);
244 SkASSERT((desc.fHeight % dimY) == 0);
245 #endif
246
247 desc.fConfig = fmt_to_config(fCompressedFormat);
248 SkASSERT(fContext->getGpu()->caps()->isConfigTexturable(desc.fConfig));
249 }
250
251 return fContext->textureProvider()->refScratchTexture(
252 desc, GrTextureProvider::kApprox_ScratchTexMatch);
253 }
254
sendTextureData(GrTexture * texture,const GrSurfaceDesc & desc,const void * data,size_t rowbytes)255 void GrSWMaskHelper::sendTextureData(GrTexture *texture, const GrSurfaceDesc& desc,
256 const void *data, size_t rowbytes) {
257 // If we aren't reusing scratch textures we don't need to flush before
258 // writing since no one else will be using 'texture'
259 bool reuseScratch = fContext->getGpu()->caps()->reuseScratchTextures();
260
261 // Since we're uploading to it, and it's compressed, 'texture' shouldn't
262 // have a render target.
263 SkASSERT(NULL == texture->asRenderTarget());
264
265 texture->writePixels(0, 0, desc.fWidth, desc.fHeight,
266 desc.fConfig, data, rowbytes,
267 reuseScratch ? 0 : GrContext::kDontFlush_PixelOpsFlag);
268 }
269
compressTextureData(GrTexture * texture,const GrSurfaceDesc & desc)270 void GrSWMaskHelper::compressTextureData(GrTexture *texture, const GrSurfaceDesc& desc) {
271
272 SkASSERT(GrPixelConfigIsCompressed(desc.fConfig));
273 SkASSERT(fmt_to_config(fCompressedFormat) == desc.fConfig);
274
275 SkAutoDataUnref cmpData(SkTextureCompressor::CompressBitmapToFormat(fBM, fCompressedFormat));
276 SkASSERT(cmpData);
277
278 this->sendTextureData(texture, desc, cmpData->data(), 0);
279 }
280
281 /**
282 * Move the result of the software mask generation back to the gpu
283 */
toTexture(GrTexture * texture)284 void GrSWMaskHelper::toTexture(GrTexture *texture) {
285 SkAutoLockPixels alp(fBM);
286
287 GrSurfaceDesc desc;
288 desc.fWidth = fBM.width();
289 desc.fHeight = fBM.height();
290 desc.fConfig = texture->config();
291
292 // First see if we should compress this texture before uploading.
293 switch (fCompressionMode) {
294 case kNone_CompressionMode:
295 this->sendTextureData(texture, desc, fBM.getPixels(), fBM.rowBytes());
296 break;
297
298 case kCompress_CompressionMode:
299 this->compressTextureData(texture, desc);
300 break;
301
302 case kBlitter_CompressionMode:
303 SkASSERT(fCompressedBuffer.get());
304 this->sendTextureData(texture, desc, fCompressedBuffer.get(), 0);
305 break;
306 }
307 }
308
309 /**
310 * Convert mask generation results to a signed distance field
311 */
toSDF(unsigned char * sdf)312 void GrSWMaskHelper::toSDF(unsigned char* sdf) {
313 SkAutoLockPixels alp(fBM);
314
315 SkGenerateDistanceFieldFromA8Image(sdf, (const unsigned char*)fBM.getPixels(),
316 fBM.width(), fBM.height(), fBM.rowBytes());
317 }
318
319 ////////////////////////////////////////////////////////////////////////////////
320 /**
321 * Software rasterizes path to A8 mask (possibly using the context's matrix)
322 * and uploads the result to a scratch texture. Returns the resulting
323 * texture on success; NULL on failure.
324 */
DrawPathMaskToTexture(GrContext * context,const SkPath & path,const SkStrokeRec & stroke,const SkIRect & resultBounds,bool antiAlias,const SkMatrix * matrix)325 GrTexture* GrSWMaskHelper::DrawPathMaskToTexture(GrContext* context,
326 const SkPath& path,
327 const SkStrokeRec& stroke,
328 const SkIRect& resultBounds,
329 bool antiAlias,
330 const SkMatrix* matrix) {
331 GrSWMaskHelper helper(context);
332
333 if (!helper.init(resultBounds, matrix)) {
334 return NULL;
335 }
336
337 helper.draw(path, stroke, SkRegion::kReplace_Op, antiAlias, 0xFF);
338
339 GrTexture* texture(helper.createTexture());
340 if (!texture) {
341 return NULL;
342 }
343
344 helper.toTexture(texture);
345
346 return texture;
347 }
348
DrawToTargetWithPathMask(GrTexture * texture,GrDrawTarget * target,GrPipelineBuilder * pipelineBuilder,GrColor color,const SkMatrix & viewMatrix,const SkIRect & rect)349 void GrSWMaskHelper::DrawToTargetWithPathMask(GrTexture* texture,
350 GrDrawTarget* target,
351 GrPipelineBuilder* pipelineBuilder,
352 GrColor color,
353 const SkMatrix& viewMatrix,
354 const SkIRect& rect) {
355 SkMatrix invert;
356 if (!viewMatrix.invert(&invert)) {
357 return;
358 }
359 GrPipelineBuilder::AutoRestoreFragmentProcessors arfp(pipelineBuilder);
360
361 SkRect dstRect = SkRect::MakeLTRB(SK_Scalar1 * rect.fLeft,
362 SK_Scalar1 * rect.fTop,
363 SK_Scalar1 * rect.fRight,
364 SK_Scalar1 * rect.fBottom);
365
366 // We use device coords to compute the texture coordinates. We take the device coords and apply
367 // a translation so that the top-left of the device bounds maps to 0,0, and then a scaling
368 // matrix to normalized coords.
369 SkMatrix maskMatrix;
370 maskMatrix.setIDiv(texture->width(), texture->height());
371 maskMatrix.preTranslate(SkIntToScalar(-rect.fLeft), SkIntToScalar(-rect.fTop));
372
373 pipelineBuilder->addCoverageProcessor(
374 GrSimpleTextureEffect::Create(texture,
375 maskMatrix,
376 GrTextureParams::kNone_FilterMode,
377 kDevice_GrCoordSet))->unref();
378
379 target->drawRect(pipelineBuilder, color, SkMatrix::I(), dstRect, NULL, &invert);
380 }
381