1 /* 2 * Copyright 2011 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 "GrAAHairLinePathRenderer.h" 9 #include "GrBuffer.h" 10 #include "GrCaps.h" 11 #include "GrClip.h" 12 #include "GrContext.h" 13 #include "GrDefaultGeoProcFactory.h" 14 #include "GrDrawOpTest.h" 15 #include "GrOpFlushState.h" 16 #include "GrPathUtils.h" 17 #include "GrPipelineBuilder.h" 18 #include "GrProcessor.h" 19 #include "GrResourceProvider.h" 20 #include "SkGeometry.h" 21 #include "SkStroke.h" 22 #include "SkTemplates.h" 23 #include "effects/GrBezierEffect.h" 24 #include "ops/GrMeshDrawOp.h" 25 26 #define PREALLOC_PTARRAY(N) SkSTArray<(N),SkPoint, true> 27 28 // quadratics are rendered as 5-sided polys in order to bound the 29 // AA stroke around the center-curve. See comments in push_quad_index_buffer and 30 // bloat_quad. Quadratics and conics share an index buffer 31 32 // lines are rendered as: 33 // *______________* 34 // |\ -_______ /| 35 // | \ \ / | 36 // | *--------* | 37 // | / ______/ \ | 38 // */_-__________\* 39 // For: 6 vertices and 18 indices (for 6 triangles) 40 41 // Each quadratic is rendered as a five sided polygon. This poly bounds 42 // the quadratic's bounding triangle but has been expanded so that the 43 // 1-pixel wide area around the curve is inside the poly. 44 // If a,b,c are the original control points then the poly a0,b0,c0,c1,a1 45 // that is rendered would look like this: 46 // b0 47 // b 48 // 49 // a0 c0 50 // a c 51 // a1 c1 52 // Each is drawn as three triangles ((a0,a1,b0), (b0,c1,c0), (a1,c1,b0)) 53 // specified by these 9 indices: 54 static const uint16_t kQuadIdxBufPattern[] = { 55 0, 1, 2, 56 2, 4, 3, 57 1, 4, 2 58 }; 59 60 static const int kIdxsPerQuad = SK_ARRAY_COUNT(kQuadIdxBufPattern); 61 static const int kQuadNumVertices = 5; 62 static const int kQuadsNumInIdxBuffer = 256; 63 GR_DECLARE_STATIC_UNIQUE_KEY(gQuadsIndexBufferKey); 64 65 static const GrBuffer* ref_quads_index_buffer(GrResourceProvider* resourceProvider) { 66 GR_DEFINE_STATIC_UNIQUE_KEY(gQuadsIndexBufferKey); 67 return resourceProvider->findOrCreateInstancedIndexBuffer( 68 kQuadIdxBufPattern, kIdxsPerQuad, kQuadsNumInIdxBuffer, kQuadNumVertices, 69 gQuadsIndexBufferKey); 70 } 71 72 73 // Each line segment is rendered as two quads and two triangles. 74 // p0 and p1 have alpha = 1 while all other points have alpha = 0. 75 // The four external points are offset 1 pixel perpendicular to the 76 // line and half a pixel parallel to the line. 77 // 78 // p4 p5 79 // p0 p1 80 // p2 p3 81 // 82 // Each is drawn as six triangles specified by these 18 indices: 83 84 static const uint16_t kLineSegIdxBufPattern[] = { 85 0, 1, 3, 86 0, 3, 2, 87 0, 4, 5, 88 0, 5, 1, 89 0, 2, 4, 90 1, 5, 3 91 }; 92 93 static const int kIdxsPerLineSeg = SK_ARRAY_COUNT(kLineSegIdxBufPattern); 94 static const int kLineSegNumVertices = 6; 95 static const int kLineSegsNumInIdxBuffer = 256; 96 97 GR_DECLARE_STATIC_UNIQUE_KEY(gLinesIndexBufferKey); 98 99 static const GrBuffer* ref_lines_index_buffer(GrResourceProvider* resourceProvider) { 100 GR_DEFINE_STATIC_UNIQUE_KEY(gLinesIndexBufferKey); 101 return resourceProvider->findOrCreateInstancedIndexBuffer( 102 kLineSegIdxBufPattern, kIdxsPerLineSeg, kLineSegsNumInIdxBuffer, kLineSegNumVertices, 103 gLinesIndexBufferKey); 104 } 105 106 // Takes 178th time of logf on Z600 / VC2010 107 static int get_float_exp(float x) { 108 GR_STATIC_ASSERT(sizeof(int) == sizeof(float)); 109 #ifdef SK_DEBUG 110 static bool tested; 111 if (!tested) { 112 tested = true; 113 SkASSERT(get_float_exp(0.25f) == -2); 114 SkASSERT(get_float_exp(0.3f) == -2); 115 SkASSERT(get_float_exp(0.5f) == -1); 116 SkASSERT(get_float_exp(1.f) == 0); 117 SkASSERT(get_float_exp(2.f) == 1); 118 SkASSERT(get_float_exp(2.5f) == 1); 119 SkASSERT(get_float_exp(8.f) == 3); 120 SkASSERT(get_float_exp(100.f) == 6); 121 SkASSERT(get_float_exp(1000.f) == 9); 122 SkASSERT(get_float_exp(1024.f) == 10); 123 SkASSERT(get_float_exp(3000000.f) == 21); 124 } 125 #endif 126 const int* iptr = (const int*)&x; 127 return (((*iptr) & 0x7f800000) >> 23) - 127; 128 } 129 130 // Uses the max curvature function for quads to estimate 131 // where to chop the conic. If the max curvature is not 132 // found along the curve segment it will return 1 and 133 // dst[0] is the original conic. If it returns 2 the dst[0] 134 // and dst[1] are the two new conics. 135 static int split_conic(const SkPoint src[3], SkConic dst[2], const SkScalar weight) { 136 SkScalar t = SkFindQuadMaxCurvature(src); 137 if (t == 0) { 138 if (dst) { 139 dst[0].set(src, weight); 140 } 141 return 1; 142 } else { 143 if (dst) { 144 SkConic conic; 145 conic.set(src, weight); 146 if (!conic.chopAt(t, dst)) { 147 dst[0].set(src, weight); 148 return 1; 149 } 150 } 151 return 2; 152 } 153 } 154 155 // Calls split_conic on the entire conic and then once more on each subsection. 156 // Most cases will result in either 1 conic (chop point is not within t range) 157 // or 3 points (split once and then one subsection is split again). 158 static int chop_conic(const SkPoint src[3], SkConic dst[4], const SkScalar weight) { 159 SkConic dstTemp[2]; 160 int conicCnt = split_conic(src, dstTemp, weight); 161 if (2 == conicCnt) { 162 int conicCnt2 = split_conic(dstTemp[0].fPts, dst, dstTemp[0].fW); 163 conicCnt = conicCnt2 + split_conic(dstTemp[1].fPts, &dst[conicCnt2], dstTemp[1].fW); 164 } else { 165 dst[0] = dstTemp[0]; 166 } 167 return conicCnt; 168 } 169 170 // returns 0 if quad/conic is degen or close to it 171 // in this case approx the path with lines 172 // otherwise returns 1 173 static int is_degen_quad_or_conic(const SkPoint p[3], SkScalar* dsqd) { 174 static const SkScalar gDegenerateToLineTol = GrPathUtils::kDefaultTolerance; 175 static const SkScalar gDegenerateToLineTolSqd = 176 gDegenerateToLineTol * gDegenerateToLineTol; 177 178 if (p[0].distanceToSqd(p[1]) < gDegenerateToLineTolSqd || 179 p[1].distanceToSqd(p[2]) < gDegenerateToLineTolSqd) { 180 return 1; 181 } 182 183 *dsqd = p[1].distanceToLineBetweenSqd(p[0], p[2]); 184 if (*dsqd < gDegenerateToLineTolSqd) { 185 return 1; 186 } 187 188 if (p[2].distanceToLineBetweenSqd(p[1], p[0]) < gDegenerateToLineTolSqd) { 189 return 1; 190 } 191 return 0; 192 } 193 194 static int is_degen_quad_or_conic(const SkPoint p[3]) { 195 SkScalar dsqd; 196 return is_degen_quad_or_conic(p, &dsqd); 197 } 198 199 // we subdivide the quads to avoid huge overfill 200 // if it returns -1 then should be drawn as lines 201 static int num_quad_subdivs(const SkPoint p[3]) { 202 SkScalar dsqd; 203 if (is_degen_quad_or_conic(p, &dsqd)) { 204 return -1; 205 } 206 207 // tolerance of triangle height in pixels 208 // tuned on windows Quadro FX 380 / Z600 209 // trade off of fill vs cpu time on verts 210 // maybe different when do this using gpu (geo or tess shaders) 211 static const SkScalar gSubdivTol = 175 * SK_Scalar1; 212 213 if (dsqd <= gSubdivTol * gSubdivTol) { 214 return 0; 215 } else { 216 static const int kMaxSub = 4; 217 // subdividing the quad reduces d by 4. so we want x = log4(d/tol) 218 // = log4(d*d/tol*tol)/2 219 // = log2(d*d/tol*tol) 220 221 // +1 since we're ignoring the mantissa contribution. 222 int log = get_float_exp(dsqd/(gSubdivTol*gSubdivTol)) + 1; 223 log = SkTMin(SkTMax(0, log), kMaxSub); 224 return log; 225 } 226 } 227 228 /** 229 * Generates the lines and quads to be rendered. Lines are always recorded in 230 * device space. We will do a device space bloat to account for the 1pixel 231 * thickness. 232 * Quads are recorded in device space unless m contains 233 * perspective, then in they are in src space. We do this because we will 234 * subdivide large quads to reduce over-fill. This subdivision has to be 235 * performed before applying the perspective matrix. 236 */ 237 static int gather_lines_and_quads(const SkPath& path, 238 const SkMatrix& m, 239 const SkIRect& devClipBounds, 240 GrAAHairLinePathRenderer::PtArray* lines, 241 GrAAHairLinePathRenderer::PtArray* quads, 242 GrAAHairLinePathRenderer::PtArray* conics, 243 GrAAHairLinePathRenderer::IntArray* quadSubdivCnts, 244 GrAAHairLinePathRenderer::FloatArray* conicWeights) { 245 SkPath::Iter iter(path, false); 246 247 int totalQuadCount = 0; 248 SkRect bounds; 249 SkIRect ibounds; 250 251 bool persp = m.hasPerspective(); 252 253 for (;;) { 254 SkPoint pathPts[4]; 255 SkPoint devPts[4]; 256 SkPath::Verb verb = iter.next(pathPts); 257 switch (verb) { 258 case SkPath::kConic_Verb: { 259 SkConic dst[4]; 260 // We chop the conics to create tighter clipping to hide error 261 // that appears near max curvature of very thin conics. Thin 262 // hyperbolas with high weight still show error. 263 int conicCnt = chop_conic(pathPts, dst, iter.conicWeight()); 264 for (int i = 0; i < conicCnt; ++i) { 265 SkPoint* chopPnts = dst[i].fPts; 266 m.mapPoints(devPts, chopPnts, 3); 267 bounds.setBounds(devPts, 3); 268 bounds.outset(SK_Scalar1, SK_Scalar1); 269 bounds.roundOut(&ibounds); 270 if (SkIRect::Intersects(devClipBounds, ibounds)) { 271 if (is_degen_quad_or_conic(devPts)) { 272 SkPoint* pts = lines->push_back_n(4); 273 pts[0] = devPts[0]; 274 pts[1] = devPts[1]; 275 pts[2] = devPts[1]; 276 pts[3] = devPts[2]; 277 } else { 278 // when in perspective keep conics in src space 279 SkPoint* cPts = persp ? chopPnts : devPts; 280 SkPoint* pts = conics->push_back_n(3); 281 pts[0] = cPts[0]; 282 pts[1] = cPts[1]; 283 pts[2] = cPts[2]; 284 conicWeights->push_back() = dst[i].fW; 285 } 286 } 287 } 288 break; 289 } 290 case SkPath::kMove_Verb: 291 break; 292 case SkPath::kLine_Verb: 293 m.mapPoints(devPts, pathPts, 2); 294 bounds.setBounds(devPts, 2); 295 bounds.outset(SK_Scalar1, SK_Scalar1); 296 bounds.roundOut(&ibounds); 297 if (SkIRect::Intersects(devClipBounds, ibounds)) { 298 SkPoint* pts = lines->push_back_n(2); 299 pts[0] = devPts[0]; 300 pts[1] = devPts[1]; 301 } 302 break; 303 case SkPath::kQuad_Verb: { 304 SkPoint choppedPts[5]; 305 // Chopping the quad helps when the quad is either degenerate or nearly degenerate. 306 // When it is degenerate it allows the approximation with lines to work since the 307 // chop point (if there is one) will be at the parabola's vertex. In the nearly 308 // degenerate the QuadUVMatrix computed for the points is almost singular which 309 // can cause rendering artifacts. 310 int n = SkChopQuadAtMaxCurvature(pathPts, choppedPts); 311 for (int i = 0; i < n; ++i) { 312 SkPoint* quadPts = choppedPts + i * 2; 313 m.mapPoints(devPts, quadPts, 3); 314 bounds.setBounds(devPts, 3); 315 bounds.outset(SK_Scalar1, SK_Scalar1); 316 bounds.roundOut(&ibounds); 317 318 if (SkIRect::Intersects(devClipBounds, ibounds)) { 319 int subdiv = num_quad_subdivs(devPts); 320 SkASSERT(subdiv >= -1); 321 if (-1 == subdiv) { 322 SkPoint* pts = lines->push_back_n(4); 323 pts[0] = devPts[0]; 324 pts[1] = devPts[1]; 325 pts[2] = devPts[1]; 326 pts[3] = devPts[2]; 327 } else { 328 // when in perspective keep quads in src space 329 SkPoint* qPts = persp ? quadPts : devPts; 330 SkPoint* pts = quads->push_back_n(3); 331 pts[0] = qPts[0]; 332 pts[1] = qPts[1]; 333 pts[2] = qPts[2]; 334 quadSubdivCnts->push_back() = subdiv; 335 totalQuadCount += 1 << subdiv; 336 } 337 } 338 } 339 break; 340 } 341 case SkPath::kCubic_Verb: 342 m.mapPoints(devPts, pathPts, 4); 343 bounds.setBounds(devPts, 4); 344 bounds.outset(SK_Scalar1, SK_Scalar1); 345 bounds.roundOut(&ibounds); 346 if (SkIRect::Intersects(devClipBounds, ibounds)) { 347 PREALLOC_PTARRAY(32) q; 348 // We convert cubics to quadratics (for now). 349 // In perspective have to do conversion in src space. 350 if (persp) { 351 SkScalar tolScale = 352 GrPathUtils::scaleToleranceToSrc(SK_Scalar1, m, path.getBounds()); 353 GrPathUtils::convertCubicToQuads(pathPts, tolScale, &q); 354 } else { 355 GrPathUtils::convertCubicToQuads(devPts, SK_Scalar1, &q); 356 } 357 for (int i = 0; i < q.count(); i += 3) { 358 SkPoint* qInDevSpace; 359 // bounds has to be calculated in device space, but q is 360 // in src space when there is perspective. 361 if (persp) { 362 m.mapPoints(devPts, &q[i], 3); 363 bounds.setBounds(devPts, 3); 364 qInDevSpace = devPts; 365 } else { 366 bounds.setBounds(&q[i], 3); 367 qInDevSpace = &q[i]; 368 } 369 bounds.outset(SK_Scalar1, SK_Scalar1); 370 bounds.roundOut(&ibounds); 371 if (SkIRect::Intersects(devClipBounds, ibounds)) { 372 int subdiv = num_quad_subdivs(qInDevSpace); 373 SkASSERT(subdiv >= -1); 374 if (-1 == subdiv) { 375 SkPoint* pts = lines->push_back_n(4); 376 // lines should always be in device coords 377 pts[0] = qInDevSpace[0]; 378 pts[1] = qInDevSpace[1]; 379 pts[2] = qInDevSpace[1]; 380 pts[3] = qInDevSpace[2]; 381 } else { 382 SkPoint* pts = quads->push_back_n(3); 383 // q is already in src space when there is no 384 // perspective and dev coords otherwise. 385 pts[0] = q[0 + i]; 386 pts[1] = q[1 + i]; 387 pts[2] = q[2 + i]; 388 quadSubdivCnts->push_back() = subdiv; 389 totalQuadCount += 1 << subdiv; 390 } 391 } 392 } 393 } 394 break; 395 case SkPath::kClose_Verb: 396 break; 397 case SkPath::kDone_Verb: 398 return totalQuadCount; 399 } 400 } 401 } 402 403 struct LineVertex { 404 SkPoint fPos; 405 float fCoverage; 406 }; 407 408 struct BezierVertex { 409 SkPoint fPos; 410 union { 411 struct { 412 SkScalar fKLM[3]; 413 } fConic; 414 SkVector fQuadCoord; 415 struct { 416 SkScalar fBogus[4]; 417 }; 418 }; 419 }; 420 421 GR_STATIC_ASSERT(sizeof(BezierVertex) == 3 * sizeof(SkPoint)); 422 423 static void intersect_lines(const SkPoint& ptA, const SkVector& normA, 424 const SkPoint& ptB, const SkVector& normB, 425 SkPoint* result) { 426 427 SkScalar lineAW = -normA.dot(ptA); 428 SkScalar lineBW = -normB.dot(ptB); 429 430 SkScalar wInv = normA.fX * normB.fY - normA.fY * normB.fX; 431 wInv = SkScalarInvert(wInv); 432 433 result->fX = normA.fY * lineBW - lineAW * normB.fY; 434 result->fX *= wInv; 435 436 result->fY = lineAW * normB.fX - normA.fX * lineBW; 437 result->fY *= wInv; 438 } 439 440 static void set_uv_quad(const SkPoint qpts[3], BezierVertex verts[kQuadNumVertices]) { 441 // this should be in the src space, not dev coords, when we have perspective 442 GrPathUtils::QuadUVMatrix DevToUV(qpts); 443 DevToUV.apply<kQuadNumVertices, sizeof(BezierVertex), sizeof(SkPoint)>(verts); 444 } 445 446 static void bloat_quad(const SkPoint qpts[3], const SkMatrix* toDevice, 447 const SkMatrix* toSrc, BezierVertex verts[kQuadNumVertices]) { 448 SkASSERT(!toDevice == !toSrc); 449 // original quad is specified by tri a,b,c 450 SkPoint a = qpts[0]; 451 SkPoint b = qpts[1]; 452 SkPoint c = qpts[2]; 453 454 if (toDevice) { 455 toDevice->mapPoints(&a, 1); 456 toDevice->mapPoints(&b, 1); 457 toDevice->mapPoints(&c, 1); 458 } 459 // make a new poly where we replace a and c by a 1-pixel wide edges orthog 460 // to edges ab and bc: 461 // 462 // before | after 463 // | b0 464 // b | 465 // | 466 // | a0 c0 467 // a c | a1 c1 468 // 469 // edges a0->b0 and b0->c0 are parallel to original edges a->b and b->c, 470 // respectively. 471 BezierVertex& a0 = verts[0]; 472 BezierVertex& a1 = verts[1]; 473 BezierVertex& b0 = verts[2]; 474 BezierVertex& c0 = verts[3]; 475 BezierVertex& c1 = verts[4]; 476 477 SkVector ab = b; 478 ab -= a; 479 SkVector ac = c; 480 ac -= a; 481 SkVector cb = b; 482 cb -= c; 483 484 // We should have already handled degenerates 485 SkASSERT(ab.length() > 0 && cb.length() > 0); 486 487 ab.normalize(); 488 SkVector abN; 489 abN.setOrthog(ab, SkVector::kLeft_Side); 490 if (abN.dot(ac) > 0) { 491 abN.negate(); 492 } 493 494 cb.normalize(); 495 SkVector cbN; 496 cbN.setOrthog(cb, SkVector::kLeft_Side); 497 if (cbN.dot(ac) < 0) { 498 cbN.negate(); 499 } 500 501 a0.fPos = a; 502 a0.fPos += abN; 503 a1.fPos = a; 504 a1.fPos -= abN; 505 506 c0.fPos = c; 507 c0.fPos += cbN; 508 c1.fPos = c; 509 c1.fPos -= cbN; 510 511 intersect_lines(a0.fPos, abN, c0.fPos, cbN, &b0.fPos); 512 513 if (toSrc) { 514 toSrc->mapPointsWithStride(&verts[0].fPos, sizeof(BezierVertex), kQuadNumVertices); 515 } 516 } 517 518 // Equations based off of Loop-Blinn Quadratic GPU Rendering 519 // Input Parametric: 520 // P(t) = (P0*(1-t)^2 + 2*w*P1*t*(1-t) + P2*t^2) / (1-t)^2 + 2*w*t*(1-t) + t^2) 521 // Output Implicit: 522 // f(x, y, w) = f(P) = K^2 - LM 523 // K = dot(k, P), L = dot(l, P), M = dot(m, P) 524 // k, l, m are calculated in function GrPathUtils::getConicKLM 525 static void set_conic_coeffs(const SkPoint p[3], BezierVertex verts[kQuadNumVertices], 526 const SkScalar weight) { 527 SkMatrix klm; 528 529 GrPathUtils::getConicKLM(p, weight, &klm); 530 531 for (int i = 0; i < kQuadNumVertices; ++i) { 532 const SkScalar pt3[3] = {verts[i].fPos.x(), verts[i].fPos.y(), 1.f}; 533 klm.mapHomogeneousPoints(verts[i].fConic.fKLM, pt3, 1); 534 } 535 } 536 537 static void add_conics(const SkPoint p[3], 538 const SkScalar weight, 539 const SkMatrix* toDevice, 540 const SkMatrix* toSrc, 541 BezierVertex** vert) { 542 bloat_quad(p, toDevice, toSrc, *vert); 543 set_conic_coeffs(p, *vert, weight); 544 *vert += kQuadNumVertices; 545 } 546 547 static void add_quads(const SkPoint p[3], 548 int subdiv, 549 const SkMatrix* toDevice, 550 const SkMatrix* toSrc, 551 BezierVertex** vert) { 552 SkASSERT(subdiv >= 0); 553 if (subdiv) { 554 SkPoint newP[5]; 555 SkChopQuadAtHalf(p, newP); 556 add_quads(newP + 0, subdiv-1, toDevice, toSrc, vert); 557 add_quads(newP + 2, subdiv-1, toDevice, toSrc, vert); 558 } else { 559 bloat_quad(p, toDevice, toSrc, *vert); 560 set_uv_quad(p, *vert); 561 *vert += kQuadNumVertices; 562 } 563 } 564 565 static void add_line(const SkPoint p[2], 566 const SkMatrix* toSrc, 567 uint8_t coverage, 568 LineVertex** vert) { 569 const SkPoint& a = p[0]; 570 const SkPoint& b = p[1]; 571 572 SkVector ortho, vec = b; 573 vec -= a; 574 575 if (vec.setLength(SK_ScalarHalf)) { 576 // Create a vector orthogonal to 'vec' and of unit length 577 ortho.fX = 2.0f * vec.fY; 578 ortho.fY = -2.0f * vec.fX; 579 580 float floatCoverage = GrNormalizeByteToFloat(coverage); 581 582 (*vert)[0].fPos = a; 583 (*vert)[0].fCoverage = floatCoverage; 584 (*vert)[1].fPos = b; 585 (*vert)[1].fCoverage = floatCoverage; 586 (*vert)[2].fPos = a - vec + ortho; 587 (*vert)[2].fCoverage = 0; 588 (*vert)[3].fPos = b + vec + ortho; 589 (*vert)[3].fCoverage = 0; 590 (*vert)[4].fPos = a - vec - ortho; 591 (*vert)[4].fCoverage = 0; 592 (*vert)[5].fPos = b + vec - ortho; 593 (*vert)[5].fCoverage = 0; 594 595 if (toSrc) { 596 toSrc->mapPointsWithStride(&(*vert)->fPos, 597 sizeof(LineVertex), 598 kLineSegNumVertices); 599 } 600 } else { 601 // just make it degenerate and likely offscreen 602 for (int i = 0; i < kLineSegNumVertices; ++i) { 603 (*vert)[i].fPos.set(SK_ScalarMax, SK_ScalarMax); 604 } 605 } 606 607 *vert += kLineSegNumVertices; 608 } 609 610 /////////////////////////////////////////////////////////////////////////////// 611 612 bool GrAAHairLinePathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const { 613 if (GrAAType::kCoverage != args.fAAType) { 614 return false; 615 } 616 617 if (!IsStrokeHairlineOrEquivalent(args.fShape->style(), *args.fViewMatrix, nullptr)) { 618 return false; 619 } 620 621 // We don't currently handle dashing in this class though perhaps we should. 622 if (args.fShape->style().pathEffect()) { 623 return false; 624 } 625 626 if (SkPath::kLine_SegmentMask == args.fShape->segmentMask() || 627 args.fShaderCaps->shaderDerivativeSupport()) { 628 return true; 629 } 630 631 return false; 632 } 633 634 template <class VertexType> 635 bool check_bounds(const SkMatrix& viewMatrix, const SkRect& devBounds, void* vertices, int vCount) 636 { 637 SkRect tolDevBounds = devBounds; 638 // The bounds ought to be tight, but in perspective the below code runs the verts 639 // through the view matrix to get back to dev coords, which can introduce imprecision. 640 if (viewMatrix.hasPerspective()) { 641 tolDevBounds.outset(SK_Scalar1 / 1000, SK_Scalar1 / 1000); 642 } else { 643 // Non-persp matrices cause this path renderer to draw in device space. 644 SkASSERT(viewMatrix.isIdentity()); 645 } 646 SkRect actualBounds; 647 648 VertexType* verts = reinterpret_cast<VertexType*>(vertices); 649 bool first = true; 650 for (int i = 0; i < vCount; ++i) { 651 SkPoint pos = verts[i].fPos; 652 // This is a hack to workaround the fact that we move some degenerate segments offscreen. 653 if (SK_ScalarMax == pos.fX) { 654 continue; 655 } 656 viewMatrix.mapPoints(&pos, 1); 657 if (first) { 658 actualBounds.set(pos.fX, pos.fY, pos.fX, pos.fY); 659 first = false; 660 } else { 661 actualBounds.growToInclude(pos.fX, pos.fY); 662 } 663 } 664 if (!first) { 665 return tolDevBounds.contains(actualBounds); 666 } 667 668 return true; 669 } 670 671 class AAHairlineOp final : public GrMeshDrawOp { 672 public: 673 DEFINE_OP_CLASS_ID 674 675 static std::unique_ptr<GrMeshDrawOp> Make(GrColor color, 676 const SkMatrix& viewMatrix, 677 const SkPath& path, 678 const GrStyle& style, 679 const SkIRect& devClipBounds) { 680 SkScalar hairlineCoverage; 681 uint8_t newCoverage = 0xff; 682 if (GrPathRenderer::IsStrokeHairlineOrEquivalent(style, viewMatrix, &hairlineCoverage)) { 683 newCoverage = SkScalarRoundToInt(hairlineCoverage * 0xff); 684 } 685 686 return std::unique_ptr<GrMeshDrawOp>( 687 new AAHairlineOp(color, newCoverage, viewMatrix, path, devClipBounds)); 688 } 689 690 const char* name() const override { return "AAHairlineOp"; } 691 692 SkString dumpInfo() const override { 693 SkString string; 694 string.appendf("Color: 0x%08x Coverage: 0x%02x, Count: %d\n", fColor, fCoverage, 695 fPaths.count()); 696 string.append(INHERITED::dumpInfo()); 697 return string; 698 } 699 700 private: 701 AAHairlineOp(GrColor color, 702 uint8_t coverage, 703 const SkMatrix& viewMatrix, 704 const SkPath& path, 705 SkIRect devClipBounds) 706 : INHERITED(ClassID()), fColor(color), fCoverage(coverage) { 707 fPaths.emplace_back(PathData{viewMatrix, path, devClipBounds}); 708 709 this->setTransformedBounds(path.getBounds(), viewMatrix, HasAABloat::kYes, 710 IsZeroArea::kYes); 711 } 712 713 void getFragmentProcessorAnalysisInputs(GrPipelineAnalysisColor* color, 714 GrPipelineAnalysisCoverage* coverage) const override { 715 color->setToConstant(fColor); 716 *coverage = GrPipelineAnalysisCoverage::kSingleChannel; 717 } 718 719 void applyPipelineOptimizations(const GrPipelineOptimizations& optimizations) override { 720 optimizations.getOverrideColorIfSet(&fColor); 721 fUsesLocalCoords = optimizations.readsLocalCoords(); 722 } 723 724 void onPrepareDraws(Target*) const override; 725 726 typedef SkTArray<SkPoint, true> PtArray; 727 typedef SkTArray<int, true> IntArray; 728 typedef SkTArray<float, true> FloatArray; 729 730 bool onCombineIfPossible(GrOp* t, const GrCaps& caps) override { 731 AAHairlineOp* that = t->cast<AAHairlineOp>(); 732 733 if (!GrPipeline::CanCombine(*this->pipeline(), this->bounds(), *that->pipeline(), 734 that->bounds(), caps)) { 735 return false; 736 } 737 738 if (this->viewMatrix().hasPerspective() != that->viewMatrix().hasPerspective()) { 739 return false; 740 } 741 742 // We go to identity if we don't have perspective 743 if (this->viewMatrix().hasPerspective() && 744 !this->viewMatrix().cheapEqualTo(that->viewMatrix())) { 745 return false; 746 } 747 748 // TODO we can actually combine hairlines if they are the same color in a kind of bulk 749 // method but we haven't implemented this yet 750 // TODO investigate going to vertex color and coverage? 751 if (this->coverage() != that->coverage()) { 752 return false; 753 } 754 755 if (this->color() != that->color()) { 756 return false; 757 } 758 759 SkASSERT(this->usesLocalCoords() == that->usesLocalCoords()); 760 if (this->usesLocalCoords() && !this->viewMatrix().cheapEqualTo(that->viewMatrix())) { 761 return false; 762 } 763 764 fPaths.push_back_n(that->fPaths.count(), that->fPaths.begin()); 765 this->joinBounds(*that); 766 return true; 767 } 768 769 GrColor color() const { return fColor; } 770 uint8_t coverage() const { return fCoverage; } 771 bool usesLocalCoords() const { return fUsesLocalCoords; } 772 const SkMatrix& viewMatrix() const { return fPaths[0].fViewMatrix; } 773 774 struct PathData { 775 SkMatrix fViewMatrix; 776 SkPath fPath; 777 SkIRect fDevClipBounds; 778 }; 779 780 GrColor fColor; 781 uint8_t fCoverage; 782 bool fUsesLocalCoords; 783 784 SkSTArray<1, PathData, true> fPaths; 785 786 typedef GrMeshDrawOp INHERITED; 787 }; 788 789 void AAHairlineOp::onPrepareDraws(Target* target) const { 790 // Setup the viewmatrix and localmatrix for the GrGeometryProcessor. 791 SkMatrix invert; 792 if (!this->viewMatrix().invert(&invert)) { 793 return; 794 } 795 796 // we will transform to identity space if the viewmatrix does not have perspective 797 bool hasPerspective = this->viewMatrix().hasPerspective(); 798 const SkMatrix* geometryProcessorViewM = &SkMatrix::I(); 799 const SkMatrix* geometryProcessorLocalM = &invert; 800 const SkMatrix* toDevice = nullptr; 801 const SkMatrix* toSrc = nullptr; 802 if (hasPerspective) { 803 geometryProcessorViewM = &this->viewMatrix(); 804 geometryProcessorLocalM = &SkMatrix::I(); 805 toDevice = &this->viewMatrix(); 806 toSrc = &invert; 807 } 808 809 // This is hand inlined for maximum performance. 810 PREALLOC_PTARRAY(128) lines; 811 PREALLOC_PTARRAY(128) quads; 812 PREALLOC_PTARRAY(128) conics; 813 IntArray qSubdivs; 814 FloatArray cWeights; 815 int quadCount = 0; 816 817 int instanceCount = fPaths.count(); 818 for (int i = 0; i < instanceCount; i++) { 819 const PathData& args = fPaths[i]; 820 quadCount += gather_lines_and_quads(args.fPath, args.fViewMatrix, args.fDevClipBounds, 821 &lines, &quads, &conics, &qSubdivs, &cWeights); 822 } 823 824 int lineCount = lines.count() / 2; 825 int conicCount = conics.count() / 3; 826 827 // do lines first 828 if (lineCount) { 829 sk_sp<GrGeometryProcessor> lineGP; 830 { 831 using namespace GrDefaultGeoProcFactory; 832 833 Color color(this->color()); 834 LocalCoords localCoords(this->usesLocalCoords() ? LocalCoords::kUsePosition_Type : 835 LocalCoords::kUnused_Type); 836 localCoords.fMatrix = geometryProcessorLocalM; 837 lineGP = GrDefaultGeoProcFactory::Make(color, Coverage::kAttribute_Type, localCoords, 838 *geometryProcessorViewM); 839 } 840 841 sk_sp<const GrBuffer> linesIndexBuffer( 842 ref_lines_index_buffer(target->resourceProvider())); 843 844 const GrBuffer* vertexBuffer; 845 int firstVertex; 846 847 size_t vertexStride = lineGP->getVertexStride(); 848 int vertexCount = kLineSegNumVertices * lineCount; 849 LineVertex* verts = reinterpret_cast<LineVertex*>( 850 target->makeVertexSpace(vertexStride, vertexCount, &vertexBuffer, &firstVertex)); 851 852 if (!verts|| !linesIndexBuffer) { 853 SkDebugf("Could not allocate vertices\n"); 854 return; 855 } 856 857 SkASSERT(lineGP->getVertexStride() == sizeof(LineVertex)); 858 859 for (int i = 0; i < lineCount; ++i) { 860 add_line(&lines[2*i], toSrc, this->coverage(), &verts); 861 } 862 863 GrMesh mesh; 864 mesh.initInstanced(kTriangles_GrPrimitiveType, vertexBuffer, linesIndexBuffer.get(), 865 firstVertex, kLineSegNumVertices, kIdxsPerLineSeg, lineCount, 866 kLineSegsNumInIdxBuffer); 867 target->draw(lineGP.get(), mesh); 868 } 869 870 if (quadCount || conicCount) { 871 sk_sp<GrGeometryProcessor> quadGP( 872 GrQuadEffect::Make(this->color(), 873 *geometryProcessorViewM, 874 kHairlineAA_GrProcessorEdgeType, 875 target->caps(), 876 *geometryProcessorLocalM, 877 this->usesLocalCoords(), 878 this->coverage())); 879 880 sk_sp<GrGeometryProcessor> conicGP( 881 GrConicEffect::Make(this->color(), 882 *geometryProcessorViewM, 883 kHairlineAA_GrProcessorEdgeType, 884 target->caps(), 885 *geometryProcessorLocalM, 886 this->usesLocalCoords(), 887 this->coverage())); 888 889 const GrBuffer* vertexBuffer; 890 int firstVertex; 891 892 sk_sp<const GrBuffer> quadsIndexBuffer( 893 ref_quads_index_buffer(target->resourceProvider())); 894 895 size_t vertexStride = sizeof(BezierVertex); 896 int vertexCount = kQuadNumVertices * quadCount + kQuadNumVertices * conicCount; 897 void *vertices = target->makeVertexSpace(vertexStride, vertexCount, 898 &vertexBuffer, &firstVertex); 899 900 if (!vertices || !quadsIndexBuffer) { 901 SkDebugf("Could not allocate vertices\n"); 902 return; 903 } 904 905 // Setup vertices 906 BezierVertex* bezVerts = reinterpret_cast<BezierVertex*>(vertices); 907 908 int unsubdivQuadCnt = quads.count() / 3; 909 for (int i = 0; i < unsubdivQuadCnt; ++i) { 910 SkASSERT(qSubdivs[i] >= 0); 911 add_quads(&quads[3*i], qSubdivs[i], toDevice, toSrc, &bezVerts); 912 } 913 914 // Start Conics 915 for (int i = 0; i < conicCount; ++i) { 916 add_conics(&conics[3*i], cWeights[i], toDevice, toSrc, &bezVerts); 917 } 918 919 if (quadCount > 0) { 920 GrMesh mesh; 921 mesh.initInstanced(kTriangles_GrPrimitiveType, vertexBuffer, quadsIndexBuffer.get(), 922 firstVertex, kQuadNumVertices, kIdxsPerQuad, quadCount, 923 kQuadsNumInIdxBuffer); 924 target->draw(quadGP.get(), mesh); 925 firstVertex += quadCount * kQuadNumVertices; 926 } 927 928 if (conicCount > 0) { 929 GrMesh mesh; 930 mesh.initInstanced(kTriangles_GrPrimitiveType, vertexBuffer, quadsIndexBuffer.get(), 931 firstVertex, kQuadNumVertices, kIdxsPerQuad, conicCount, 932 kQuadsNumInIdxBuffer); 933 target->draw(conicGP.get(), mesh); 934 } 935 } 936 } 937 938 bool GrAAHairLinePathRenderer::onDrawPath(const DrawPathArgs& args) { 939 GR_AUDIT_TRAIL_AUTO_FRAME(args.fRenderTargetContext->auditTrail(), 940 "GrAAHairlinePathRenderer::onDrawPath"); 941 SkASSERT(!args.fRenderTargetContext->isUnifiedMultisampled()); 942 943 SkIRect devClipBounds; 944 args.fClip->getConservativeBounds(args.fRenderTargetContext->width(), 945 args.fRenderTargetContext->height(), 946 &devClipBounds); 947 SkPath path; 948 args.fShape->asPath(&path); 949 std::unique_ptr<GrMeshDrawOp> op = AAHairlineOp::Make( 950 args.fPaint.getColor(), *args.fViewMatrix, path, args.fShape->style(), devClipBounds); 951 GrPipelineBuilder pipelineBuilder(std::move(args.fPaint), args.fAAType); 952 pipelineBuilder.setUserStencil(args.fUserStencilSettings); 953 args.fRenderTargetContext->addMeshDrawOp(pipelineBuilder, *args.fClip, std::move(op)); 954 return true; 955 } 956 957 /////////////////////////////////////////////////////////////////////////////////////////////////// 958 959 #if GR_TEST_UTILS 960 961 DRAW_OP_TEST_DEFINE(AAHairlineOp) { 962 GrColor color = GrRandomColor(random); 963 SkMatrix viewMatrix = GrTest::TestMatrix(random); 964 SkPath path = GrTest::TestPath(random); 965 SkIRect devClipBounds; 966 devClipBounds.setEmpty(); 967 return AAHairlineOp::Make(color, viewMatrix, path, GrStyle::SimpleHairline(), devClipBounds); 968 } 969 970 #endif 971
