joshualitt | 9ff6425 | 2015-08-10 09:03:51 -0700 | [diff] [blame^] | 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 "GrAAStrokeRectBatch.h" |
| 9 | |
| 10 | #include "GrDefaultGeoProcFactory.h" |
| 11 | #include "GrResourceKey.h" |
| 12 | #include "GrResourceProvider.h" |
| 13 | |
| 14 | GR_DECLARE_STATIC_UNIQUE_KEY(gMiterIndexBufferKey); |
| 15 | GR_DECLARE_STATIC_UNIQUE_KEY(gBevelIndexBufferKey); |
| 16 | |
| 17 | static void set_inset_fan(SkPoint* pts, size_t stride, |
| 18 | const SkRect& r, SkScalar dx, SkScalar dy) { |
| 19 | pts->setRectFan(r.fLeft + dx, r.fTop + dy, |
| 20 | r.fRight - dx, r.fBottom - dy, stride); |
| 21 | } |
| 22 | |
| 23 | static const GrGeometryProcessor* create_stroke_rect_gp(bool tweakAlphaForCoverage, |
| 24 | const SkMatrix& viewMatrix, |
| 25 | bool usesLocalCoords, |
| 26 | bool coverageIgnored) { |
| 27 | using namespace GrDefaultGeoProcFactory; |
| 28 | |
| 29 | Color color(Color::kAttribute_Type); |
| 30 | Coverage::Type coverageType; |
| 31 | // TODO remove coverage if coverage is ignored |
| 32 | /*if (coverageIgnored) { |
| 33 | coverageType = Coverage::kNone_Type; |
| 34 | } else*/ if (tweakAlphaForCoverage) { |
| 35 | coverageType = Coverage::kSolid_Type; |
| 36 | } else { |
| 37 | coverageType = Coverage::kAttribute_Type; |
| 38 | } |
| 39 | Coverage coverage(coverageType); |
| 40 | LocalCoords localCoords(usesLocalCoords ? LocalCoords::kUsePosition_Type : |
| 41 | LocalCoords::kUnused_Type); |
| 42 | return CreateForDeviceSpace(color, coverage, localCoords, viewMatrix); |
| 43 | } |
| 44 | |
| 45 | |
| 46 | void GrAAStrokeRectBatch::initBatchTracker(const GrPipelineInfo& init) { |
| 47 | // Handle any color overrides |
| 48 | if (!init.readsColor()) { |
| 49 | fGeoData[0].fColor = GrColor_ILLEGAL; |
| 50 | } |
| 51 | init.getOverrideColorIfSet(&fGeoData[0].fColor); |
| 52 | |
| 53 | // setup batch properties |
| 54 | fBatch.fColorIgnored = !init.readsColor(); |
| 55 | fBatch.fColor = fGeoData[0].fColor; |
| 56 | fBatch.fUsesLocalCoords = init.readsLocalCoords(); |
| 57 | fBatch.fCoverageIgnored = !init.readsCoverage(); |
| 58 | fBatch.fMiterStroke = fGeoData[0].fMiterStroke; |
| 59 | fBatch.fCanTweakAlphaForCoverage = init.canTweakAlphaForCoverage(); |
| 60 | } |
| 61 | |
| 62 | void GrAAStrokeRectBatch::generateGeometry(GrBatchTarget* batchTarget) { |
| 63 | bool canTweakAlphaForCoverage = this->canTweakAlphaForCoverage(); |
| 64 | |
| 65 | SkAutoTUnref<const GrGeometryProcessor> gp(create_stroke_rect_gp(canTweakAlphaForCoverage, |
| 66 | this->viewMatrix(), |
| 67 | this->usesLocalCoords(), |
| 68 | this->coverageIgnored())); |
| 69 | if (!gp) { |
| 70 | SkDebugf("Couldn't create GrGeometryProcessor\n"); |
| 71 | return; |
| 72 | } |
| 73 | |
| 74 | batchTarget->initDraw(gp, this->pipeline()); |
| 75 | |
| 76 | size_t vertexStride = gp->getVertexStride(); |
| 77 | |
| 78 | SkASSERT(canTweakAlphaForCoverage ? |
| 79 | vertexStride == sizeof(GrDefaultGeoProcFactory::PositionColorAttr) : |
| 80 | vertexStride == sizeof(GrDefaultGeoProcFactory::PositionColorCoverageAttr)); |
| 81 | int innerVertexNum = 4; |
| 82 | int outerVertexNum = this->miterStroke() ? 4 : 8; |
| 83 | int verticesPerInstance = (outerVertexNum + innerVertexNum) * 2; |
| 84 | int indicesPerInstance = this->miterStroke() ? kMiterIndexCnt : kBevelIndexCnt; |
| 85 | int instanceCount = fGeoData.count(); |
| 86 | |
| 87 | const SkAutoTUnref<const GrIndexBuffer> indexBuffer( |
| 88 | GetIndexBuffer(batchTarget->resourceProvider(), this->miterStroke())); |
| 89 | InstancedHelper helper; |
| 90 | void* vertices = helper.init(batchTarget, kTriangles_GrPrimitiveType, vertexStride, |
| 91 | indexBuffer, verticesPerInstance, indicesPerInstance, |
| 92 | instanceCount); |
| 93 | if (!vertices || !indexBuffer) { |
| 94 | SkDebugf("Could not allocate vertices\n"); |
| 95 | return; |
| 96 | } |
| 97 | |
| 98 | for (int i = 0; i < instanceCount; i++) { |
| 99 | const Geometry& args = fGeoData[i]; |
| 100 | this->generateAAStrokeRectGeometry(vertices, |
| 101 | i * verticesPerInstance * vertexStride, |
| 102 | vertexStride, |
| 103 | outerVertexNum, |
| 104 | innerVertexNum, |
| 105 | args.fColor, |
| 106 | args.fDevOutside, |
| 107 | args.fDevOutsideAssist, |
| 108 | args.fDevInside, |
| 109 | args.fMiterStroke, |
| 110 | canTweakAlphaForCoverage); |
| 111 | } |
| 112 | helper.issueDraw(batchTarget); |
| 113 | } |
| 114 | |
| 115 | const GrIndexBuffer* GrAAStrokeRectBatch::GetIndexBuffer(GrResourceProvider* resourceProvider, |
| 116 | bool miterStroke) { |
| 117 | |
| 118 | if (miterStroke) { |
| 119 | static const uint16_t gMiterIndices[] = { |
| 120 | 0 + 0, 1 + 0, 5 + 0, 5 + 0, 4 + 0, 0 + 0, |
| 121 | 1 + 0, 2 + 0, 6 + 0, 6 + 0, 5 + 0, 1 + 0, |
| 122 | 2 + 0, 3 + 0, 7 + 0, 7 + 0, 6 + 0, 2 + 0, |
| 123 | 3 + 0, 0 + 0, 4 + 0, 4 + 0, 7 + 0, 3 + 0, |
| 124 | |
| 125 | 0 + 4, 1 + 4, 5 + 4, 5 + 4, 4 + 4, 0 + 4, |
| 126 | 1 + 4, 2 + 4, 6 + 4, 6 + 4, 5 + 4, 1 + 4, |
| 127 | 2 + 4, 3 + 4, 7 + 4, 7 + 4, 6 + 4, 2 + 4, |
| 128 | 3 + 4, 0 + 4, 4 + 4, 4 + 4, 7 + 4, 3 + 4, |
| 129 | |
| 130 | 0 + 8, 1 + 8, 5 + 8, 5 + 8, 4 + 8, 0 + 8, |
| 131 | 1 + 8, 2 + 8, 6 + 8, 6 + 8, 5 + 8, 1 + 8, |
| 132 | 2 + 8, 3 + 8, 7 + 8, 7 + 8, 6 + 8, 2 + 8, |
| 133 | 3 + 8, 0 + 8, 4 + 8, 4 + 8, 7 + 8, 3 + 8, |
| 134 | }; |
| 135 | GR_STATIC_ASSERT(SK_ARRAY_COUNT(gMiterIndices) == kMiterIndexCnt); |
| 136 | GR_DEFINE_STATIC_UNIQUE_KEY(gMiterIndexBufferKey); |
| 137 | return resourceProvider->findOrCreateInstancedIndexBuffer(gMiterIndices, |
| 138 | kMiterIndexCnt, kNumMiterRectsInIndexBuffer, kMiterVertexCnt, |
| 139 | gMiterIndexBufferKey); |
| 140 | } else { |
| 141 | /** |
| 142 | * As in miter-stroke, index = a + b, and a is the current index, b is the shift |
| 143 | * from the first index. The index layout: |
| 144 | * outer AA line: 0~3, 4~7 |
| 145 | * outer edge: 8~11, 12~15 |
| 146 | * inner edge: 16~19 |
| 147 | * inner AA line: 20~23 |
| 148 | * Following comes a bevel-stroke rect and its indices: |
| 149 | * |
| 150 | * 4 7 |
| 151 | * ********************************* |
| 152 | * * ______________________________ * |
| 153 | * * / 12 15 \ * |
| 154 | * * / \ * |
| 155 | * 0 * |8 16_____________________19 11 | * 3 |
| 156 | * * | | | | * |
| 157 | * * | | **************** | | * |
| 158 | * * | | * 20 23 * | | * |
| 159 | * * | | * * | | * |
| 160 | * * | | * 21 22 * | | * |
| 161 | * * | | **************** | | * |
| 162 | * * | |____________________| | * |
| 163 | * 1 * |9 17 18 10| * 2 |
| 164 | * * \ / * |
| 165 | * * \13 __________________________14/ * |
| 166 | * * * |
| 167 | * ********************************** |
| 168 | * 5 6 |
| 169 | */ |
| 170 | static const uint16_t gBevelIndices[] = { |
| 171 | // Draw outer AA, from outer AA line to outer edge, shift is 0. |
| 172 | 0 + 0, 1 + 0, 9 + 0, 9 + 0, 8 + 0, 0 + 0, |
| 173 | 1 + 0, 5 + 0, 13 + 0, 13 + 0, 9 + 0, 1 + 0, |
| 174 | 5 + 0, 6 + 0, 14 + 0, 14 + 0, 13 + 0, 5 + 0, |
| 175 | 6 + 0, 2 + 0, 10 + 0, 10 + 0, 14 + 0, 6 + 0, |
| 176 | 2 + 0, 3 + 0, 11 + 0, 11 + 0, 10 + 0, 2 + 0, |
| 177 | 3 + 0, 7 + 0, 15 + 0, 15 + 0, 11 + 0, 3 + 0, |
| 178 | 7 + 0, 4 + 0, 12 + 0, 12 + 0, 15 + 0, 7 + 0, |
| 179 | 4 + 0, 0 + 0, 8 + 0, 8 + 0, 12 + 0, 4 + 0, |
| 180 | |
| 181 | // Draw the stroke, from outer edge to inner edge, shift is 8. |
| 182 | 0 + 8, 1 + 8, 9 + 8, 9 + 8, 8 + 8, 0 + 8, |
| 183 | 1 + 8, 5 + 8, 9 + 8, |
| 184 | 5 + 8, 6 + 8, 10 + 8, 10 + 8, 9 + 8, 5 + 8, |
| 185 | 6 + 8, 2 + 8, 10 + 8, |
| 186 | 2 + 8, 3 + 8, 11 + 8, 11 + 8, 10 + 8, 2 + 8, |
| 187 | 3 + 8, 7 + 8, 11 + 8, |
| 188 | 7 + 8, 4 + 8, 8 + 8, 8 + 8, 11 + 8, 7 + 8, |
| 189 | 4 + 8, 0 + 8, 8 + 8, |
| 190 | |
| 191 | // Draw the inner AA, from inner edge to inner AA line, shift is 16. |
| 192 | 0 + 16, 1 + 16, 5 + 16, 5 + 16, 4 + 16, 0 + 16, |
| 193 | 1 + 16, 2 + 16, 6 + 16, 6 + 16, 5 + 16, 1 + 16, |
| 194 | 2 + 16, 3 + 16, 7 + 16, 7 + 16, 6 + 16, 2 + 16, |
| 195 | 3 + 16, 0 + 16, 4 + 16, 4 + 16, 7 + 16, 3 + 16, |
| 196 | }; |
| 197 | GR_STATIC_ASSERT(SK_ARRAY_COUNT(gBevelIndices) == kBevelIndexCnt); |
| 198 | |
| 199 | GR_DEFINE_STATIC_UNIQUE_KEY(gBevelIndexBufferKey); |
| 200 | return resourceProvider->findOrCreateInstancedIndexBuffer(gBevelIndices, |
| 201 | kBevelIndexCnt, kNumBevelRectsInIndexBuffer, kBevelVertexCnt, |
| 202 | gBevelIndexBufferKey); |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | bool GrAAStrokeRectBatch::onCombineIfPossible(GrBatch* t) { |
| 207 | if (!this->pipeline()->isEqual(*t->pipeline())) { |
| 208 | return false; |
| 209 | } |
| 210 | |
| 211 | GrAAStrokeRectBatch* that = t->cast<GrAAStrokeRectBatch>(); |
| 212 | |
| 213 | // TODO batch across miterstroke changes |
| 214 | if (this->miterStroke() != that->miterStroke()) { |
| 215 | return false; |
| 216 | } |
| 217 | |
| 218 | // We apply the viewmatrix to the rect points on the cpu. However, if the pipeline uses |
| 219 | // local coords then we won't be able to batch. We could actually upload the viewmatrix |
| 220 | // using vertex attributes in these cases, but haven't investigated that |
| 221 | if (this->usesLocalCoords() && !this->viewMatrix().cheapEqualTo(that->viewMatrix())) { |
| 222 | return false; |
| 223 | } |
| 224 | |
| 225 | // In the event of two batches, one who can tweak, one who cannot, we just fall back to |
| 226 | // not tweaking |
| 227 | if (this->canTweakAlphaForCoverage() != that->canTweakAlphaForCoverage()) { |
| 228 | fBatch.fCanTweakAlphaForCoverage = false; |
| 229 | } |
| 230 | |
| 231 | if (this->color() != that->color()) { |
| 232 | fBatch.fColor = GrColor_ILLEGAL; |
| 233 | } |
| 234 | fGeoData.push_back_n(that->geoData()->count(), that->geoData()->begin()); |
| 235 | this->joinBounds(that->bounds()); |
| 236 | return true; |
| 237 | } |
| 238 | |
| 239 | void GrAAStrokeRectBatch::generateAAStrokeRectGeometry(void* vertices, |
| 240 | size_t offset, |
| 241 | size_t vertexStride, |
| 242 | int outerVertexNum, |
| 243 | int innerVertexNum, |
| 244 | GrColor color, |
| 245 | const SkRect& devOutside, |
| 246 | const SkRect& devOutsideAssist, |
| 247 | const SkRect& devInside, |
| 248 | bool miterStroke, |
| 249 | bool tweakAlphaForCoverage) const { |
| 250 | intptr_t verts = reinterpret_cast<intptr_t>(vertices) + offset; |
| 251 | |
| 252 | // We create vertices for four nested rectangles. There are two ramps from 0 to full |
| 253 | // coverage, one on the exterior of the stroke and the other on the interior. |
| 254 | // The following pointers refer to the four rects, from outermost to innermost. |
| 255 | SkPoint* fan0Pos = reinterpret_cast<SkPoint*>(verts); |
| 256 | SkPoint* fan1Pos = reinterpret_cast<SkPoint*>(verts + outerVertexNum * vertexStride); |
| 257 | SkPoint* fan2Pos = reinterpret_cast<SkPoint*>(verts + 2 * outerVertexNum * vertexStride); |
| 258 | SkPoint* fan3Pos = reinterpret_cast<SkPoint*>(verts + |
| 259 | (2 * outerVertexNum + innerVertexNum) * |
| 260 | vertexStride); |
| 261 | |
| 262 | #ifndef SK_IGNORE_THIN_STROKED_RECT_FIX |
| 263 | // TODO: this only really works if the X & Y margins are the same all around |
| 264 | // the rect (or if they are all >= 1.0). |
| 265 | SkScalar inset = SkMinScalar(SK_Scalar1, devOutside.fRight - devInside.fRight); |
| 266 | inset = SkMinScalar(inset, devInside.fLeft - devOutside.fLeft); |
| 267 | inset = SkMinScalar(inset, devInside.fTop - devOutside.fTop); |
| 268 | if (miterStroke) { |
| 269 | inset = SK_ScalarHalf * SkMinScalar(inset, devOutside.fBottom - devInside.fBottom); |
| 270 | } else { |
| 271 | inset = SK_ScalarHalf * SkMinScalar(inset, devOutsideAssist.fBottom - |
| 272 | devInside.fBottom); |
| 273 | } |
| 274 | SkASSERT(inset >= 0); |
| 275 | #else |
| 276 | SkScalar inset = SK_ScalarHalf; |
| 277 | #endif |
| 278 | |
| 279 | if (miterStroke) { |
| 280 | // outermost |
| 281 | set_inset_fan(fan0Pos, vertexStride, devOutside, -SK_ScalarHalf, -SK_ScalarHalf); |
| 282 | // inner two |
| 283 | set_inset_fan(fan1Pos, vertexStride, devOutside, inset, inset); |
| 284 | set_inset_fan(fan2Pos, vertexStride, devInside, -inset, -inset); |
| 285 | // innermost |
| 286 | set_inset_fan(fan3Pos, vertexStride, devInside, SK_ScalarHalf, SK_ScalarHalf); |
| 287 | } else { |
| 288 | SkPoint* fan0AssistPos = reinterpret_cast<SkPoint*>(verts + 4 * vertexStride); |
| 289 | SkPoint* fan1AssistPos = reinterpret_cast<SkPoint*>(verts + |
| 290 | (outerVertexNum + 4) * |
| 291 | vertexStride); |
| 292 | // outermost |
| 293 | set_inset_fan(fan0Pos, vertexStride, devOutside, -SK_ScalarHalf, -SK_ScalarHalf); |
| 294 | set_inset_fan(fan0AssistPos, vertexStride, devOutsideAssist, -SK_ScalarHalf, |
| 295 | -SK_ScalarHalf); |
| 296 | // outer one of the inner two |
| 297 | set_inset_fan(fan1Pos, vertexStride, devOutside, inset, inset); |
| 298 | set_inset_fan(fan1AssistPos, vertexStride, devOutsideAssist, inset, inset); |
| 299 | // inner one of the inner two |
| 300 | set_inset_fan(fan2Pos, vertexStride, devInside, -inset, -inset); |
| 301 | // innermost |
| 302 | set_inset_fan(fan3Pos, vertexStride, devInside, SK_ScalarHalf, SK_ScalarHalf); |
| 303 | } |
| 304 | |
| 305 | // Make verts point to vertex color and then set all the color and coverage vertex attrs |
| 306 | // values. The outermost rect has 0 coverage |
| 307 | verts += sizeof(SkPoint); |
| 308 | for (int i = 0; i < outerVertexNum; ++i) { |
| 309 | if (tweakAlphaForCoverage) { |
| 310 | *reinterpret_cast<GrColor*>(verts + i * vertexStride) = 0; |
| 311 | } else { |
| 312 | *reinterpret_cast<GrColor*>(verts + i * vertexStride) = color; |
| 313 | *reinterpret_cast<float*>(verts + i * vertexStride + sizeof(GrColor)) = 0; |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | // scale is the coverage for the the inner two rects. |
| 318 | int scale; |
| 319 | if (inset < SK_ScalarHalf) { |
| 320 | scale = SkScalarFloorToInt(512.0f * inset / (inset + SK_ScalarHalf)); |
| 321 | SkASSERT(scale >= 0 && scale <= 255); |
| 322 | } else { |
| 323 | scale = 0xff; |
| 324 | } |
| 325 | |
| 326 | float innerCoverage = GrNormalizeByteToFloat(scale); |
| 327 | GrColor scaledColor = (0xff == scale) ? color : SkAlphaMulQ(color, scale); |
| 328 | |
| 329 | verts += outerVertexNum * vertexStride; |
| 330 | for (int i = 0; i < outerVertexNum + innerVertexNum; ++i) { |
| 331 | if (tweakAlphaForCoverage) { |
| 332 | *reinterpret_cast<GrColor*>(verts + i * vertexStride) = scaledColor; |
| 333 | } else { |
| 334 | *reinterpret_cast<GrColor*>(verts + i * vertexStride) = color; |
| 335 | *reinterpret_cast<float*>(verts + i * vertexStride + sizeof(GrColor)) = |
| 336 | innerCoverage; |
| 337 | } |
| 338 | } |
| 339 | |
| 340 | // The innermost rect has 0 coverage |
| 341 | verts += (outerVertexNum + innerVertexNum) * vertexStride; |
| 342 | for (int i = 0; i < innerVertexNum; ++i) { |
| 343 | if (tweakAlphaForCoverage) { |
| 344 | *reinterpret_cast<GrColor*>(verts + i * vertexStride) = 0; |
| 345 | } else { |
| 346 | *reinterpret_cast<GrColor*>(verts + i * vertexStride) = color; |
| 347 | *reinterpret_cast<GrColor*>(verts + i * vertexStride + sizeof(GrColor)) = 0; |
| 348 | } |
| 349 | } |
| 350 | } |
| 351 | |
| 352 | /////////////////////////////////////////////////////////////////////////////////////////////////// |
| 353 | |
| 354 | #ifdef GR_TEST_UTILS |
| 355 | |
| 356 | #include "GrBatchTest.h" |
| 357 | |
| 358 | BATCH_TEST_DEFINE(AAStrokeRectBatch) { |
| 359 | bool miterStroke = random->nextBool(); |
| 360 | |
| 361 | // Create mock stroke rect |
| 362 | SkRect outside = GrTest::TestRect(random); |
| 363 | SkScalar minDim = SkMinScalar(outside.width(), outside.height()); |
| 364 | SkScalar strokeWidth = minDim * 0.1f; |
| 365 | SkRect outsideAssist = outside; |
| 366 | outsideAssist.outset(strokeWidth, strokeWidth); |
| 367 | SkRect inside = outside; |
| 368 | inside.inset(strokeWidth, strokeWidth); |
| 369 | |
| 370 | GrAAStrokeRectBatch::Geometry geo; |
| 371 | geo.fColor = GrRandomColor(random); |
| 372 | geo.fDevOutside = outside; |
| 373 | geo.fDevOutsideAssist = outsideAssist; |
| 374 | geo.fDevInside = inside; |
| 375 | geo.fMiterStroke = miterStroke; |
| 376 | |
| 377 | return GrAAStrokeRectBatch::Create(geo, GrTest::TestMatrix(random)); |
| 378 | } |
| 379 | |
| 380 | #endif |