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 "GrAAConvexPathRenderer.h"
9 #include "GrCaps.h"
10 #include "GrContext.h"
11 #include "GrDrawOpTest.h"
12 #include "GrGeometryProcessor.h"
13 #include "GrPathUtils.h"
14 #include "GrProcessor.h"
15 #include "GrRenderTargetContext.h"
16 #include "GrShape.h"
17 #include "GrSimpleMeshDrawOpHelper.h"
18 #include "GrVertexWriter.h"
19 #include "SkGeometry.h"
20 #include "SkPathPriv.h"
21 #include "SkPointPriv.h"
22 #include "SkString.h"
23 #include "SkTypes.h"
24 #include "glsl/GrGLSLFragmentShaderBuilder.h"
25 #include "glsl/GrGLSLGeometryProcessor.h"
26 #include "glsl/GrGLSLProgramDataManager.h"
27 #include "glsl/GrGLSLUniformHandler.h"
28 #include "glsl/GrGLSLVarying.h"
29 #include "glsl/GrGLSLVertexGeoBuilder.h"
30 #include "ops/GrMeshDrawOp.h"
31
GrAAConvexPathRenderer()32 GrAAConvexPathRenderer::GrAAConvexPathRenderer() {
33 }
34
35 struct Segment {
36 enum {
37 // These enum values are assumed in member functions below.
38 kLine = 0,
39 kQuad = 1,
40 } fType;
41
42 // line uses one pt, quad uses 2 pts
43 SkPoint fPts[2];
44 // normal to edge ending at each pt
45 SkVector fNorms[2];
46 // is the corner where the previous segment meets this segment
47 // sharp. If so, fMid is a normalized bisector facing outward.
48 SkVector fMid;
49
countPointsSegment50 int countPoints() {
51 GR_STATIC_ASSERT(0 == kLine && 1 == kQuad);
52 return fType + 1;
53 }
endPtSegment54 const SkPoint& endPt() const {
55 GR_STATIC_ASSERT(0 == kLine && 1 == kQuad);
56 return fPts[fType];
57 }
endNormSegment58 const SkPoint& endNorm() const {
59 GR_STATIC_ASSERT(0 == kLine && 1 == kQuad);
60 return fNorms[fType];
61 }
62 };
63
64 typedef SkTArray<Segment, true> SegmentArray;
65
center_of_mass(const SegmentArray & segments,SkPoint * c)66 static bool center_of_mass(const SegmentArray& segments, SkPoint* c) {
67 SkScalar area = 0;
68 SkPoint center = {0, 0};
69 int count = segments.count();
70 SkPoint p0 = {0, 0};
71 if (count > 2) {
72 // We translate the polygon so that the first point is at the origin.
73 // This avoids some precision issues with small area polygons far away
74 // from the origin.
75 p0 = segments[0].endPt();
76 SkPoint pi;
77 SkPoint pj;
78 // the first and last iteration of the below loop would compute
79 // zeros since the starting / ending point is (0,0). So instead we start
80 // at i=1 and make the last iteration i=count-2.
81 pj = segments[1].endPt() - p0;
82 for (int i = 1; i < count - 1; ++i) {
83 pi = pj;
84 pj = segments[i + 1].endPt() - p0;
85
86 SkScalar t = SkPoint::CrossProduct(pi, pj);
87 area += t;
88 center.fX += (pi.fX + pj.fX) * t;
89 center.fY += (pi.fY + pj.fY) * t;
90 }
91 }
92
93 // If the poly has no area then we instead return the average of
94 // its points.
95 if (SkScalarNearlyZero(area)) {
96 SkPoint avg;
97 avg.set(0, 0);
98 for (int i = 0; i < count; ++i) {
99 const SkPoint& pt = segments[i].endPt();
100 avg.fX += pt.fX;
101 avg.fY += pt.fY;
102 }
103 SkScalar denom = SK_Scalar1 / count;
104 avg.scale(denom);
105 *c = avg;
106 } else {
107 area *= 3;
108 area = SkScalarInvert(area);
109 center.scale(area);
110 // undo the translate of p0 to the origin.
111 *c = center + p0;
112 }
113 return !SkScalarIsNaN(c->fX) && !SkScalarIsNaN(c->fY) && c->isFinite();
114 }
115
compute_vectors(SegmentArray * segments,SkPoint * fanPt,SkPathPriv::FirstDirection dir,int * vCount,int * iCount)116 static bool compute_vectors(SegmentArray* segments,
117 SkPoint* fanPt,
118 SkPathPriv::FirstDirection dir,
119 int* vCount,
120 int* iCount) {
121 if (!center_of_mass(*segments, fanPt)) {
122 return false;
123 }
124 int count = segments->count();
125
126 // Make the normals point towards the outside
127 SkPointPriv::Side normSide;
128 if (dir == SkPathPriv::kCCW_FirstDirection) {
129 normSide = SkPointPriv::kRight_Side;
130 } else {
131 normSide = SkPointPriv::kLeft_Side;
132 }
133
134 int64_t vCount64 = 0;
135 int64_t iCount64 = 0;
136 // compute normals at all points
137 for (int a = 0; a < count; ++a) {
138 Segment& sega = (*segments)[a];
139 int b = (a + 1) % count;
140 Segment& segb = (*segments)[b];
141
142 const SkPoint* prevPt = &sega.endPt();
143 int n = segb.countPoints();
144 for (int p = 0; p < n; ++p) {
145 segb.fNorms[p] = segb.fPts[p] - *prevPt;
146 segb.fNorms[p].normalize();
147 segb.fNorms[p] = SkPointPriv::MakeOrthog(segb.fNorms[p], normSide);
148 prevPt = &segb.fPts[p];
149 }
150 if (Segment::kLine == segb.fType) {
151 vCount64 += 5;
152 iCount64 += 9;
153 } else {
154 vCount64 += 6;
155 iCount64 += 12;
156 }
157 }
158
159 // compute mid-vectors where segments meet. TODO: Detect shallow corners
160 // and leave out the wedges and close gaps by stitching segments together.
161 for (int a = 0; a < count; ++a) {
162 const Segment& sega = (*segments)[a];
163 int b = (a + 1) % count;
164 Segment& segb = (*segments)[b];
165 segb.fMid = segb.fNorms[0] + sega.endNorm();
166 segb.fMid.normalize();
167 // corner wedges
168 vCount64 += 4;
169 iCount64 += 6;
170 }
171 if (vCount64 > SK_MaxS32 || iCount64 > SK_MaxS32) {
172 return false;
173 }
174 *vCount = vCount64;
175 *iCount = iCount64;
176 return true;
177 }
178
179 struct DegenerateTestData {
DegenerateTestDataDegenerateTestData180 DegenerateTestData() { fStage = kInitial; }
isDegenerateDegenerateTestData181 bool isDegenerate() const { return kNonDegenerate != fStage; }
182 enum {
183 kInitial,
184 kPoint,
185 kLine,
186 kNonDegenerate
187 } fStage;
188 SkPoint fFirstPoint;
189 SkVector fLineNormal;
190 SkScalar fLineC;
191 };
192
193 static const SkScalar kClose = (SK_Scalar1 / 16);
194 static const SkScalar kCloseSqd = kClose * kClose;
195
update_degenerate_test(DegenerateTestData * data,const SkPoint & pt)196 static void update_degenerate_test(DegenerateTestData* data, const SkPoint& pt) {
197 switch (data->fStage) {
198 case DegenerateTestData::kInitial:
199 data->fFirstPoint = pt;
200 data->fStage = DegenerateTestData::kPoint;
201 break;
202 case DegenerateTestData::kPoint:
203 if (SkPointPriv::DistanceToSqd(pt, data->fFirstPoint) > kCloseSqd) {
204 data->fLineNormal = pt - data->fFirstPoint;
205 data->fLineNormal.normalize();
206 data->fLineNormal = SkPointPriv::MakeOrthog(data->fLineNormal);
207 data->fLineC = -data->fLineNormal.dot(data->fFirstPoint);
208 data->fStage = DegenerateTestData::kLine;
209 }
210 break;
211 case DegenerateTestData::kLine:
212 if (SkScalarAbs(data->fLineNormal.dot(pt) + data->fLineC) > kClose) {
213 data->fStage = DegenerateTestData::kNonDegenerate;
214 }
215 case DegenerateTestData::kNonDegenerate:
216 break;
217 default:
218 SK_ABORT("Unexpected degenerate test stage.");
219 }
220 }
221
get_direction(const SkPath & path,const SkMatrix & m,SkPathPriv::FirstDirection * dir)222 static inline bool get_direction(const SkPath& path, const SkMatrix& m,
223 SkPathPriv::FirstDirection* dir) {
224 if (!SkPathPriv::CheapComputeFirstDirection(path, dir)) {
225 return false;
226 }
227 // check whether m reverses the orientation
228 SkASSERT(!m.hasPerspective());
229 SkScalar det2x2 = m.get(SkMatrix::kMScaleX) * m.get(SkMatrix::kMScaleY) -
230 m.get(SkMatrix::kMSkewX) * m.get(SkMatrix::kMSkewY);
231 if (det2x2 < 0) {
232 *dir = SkPathPriv::OppositeFirstDirection(*dir);
233 }
234 return true;
235 }
236
add_line_to_segment(const SkPoint & pt,SegmentArray * segments)237 static inline void add_line_to_segment(const SkPoint& pt,
238 SegmentArray* segments) {
239 segments->push_back();
240 segments->back().fType = Segment::kLine;
241 segments->back().fPts[0] = pt;
242 }
243
add_quad_segment(const SkPoint pts[3],SegmentArray * segments)244 static inline void add_quad_segment(const SkPoint pts[3],
245 SegmentArray* segments) {
246 if (SkPointPriv::DistanceToSqd(pts[0], pts[1]) < kCloseSqd ||
247 SkPointPriv::DistanceToSqd(pts[1], pts[2]) < kCloseSqd) {
248 if (pts[0] != pts[2]) {
249 add_line_to_segment(pts[2], segments);
250 }
251 } else {
252 segments->push_back();
253 segments->back().fType = Segment::kQuad;
254 segments->back().fPts[0] = pts[1];
255 segments->back().fPts[1] = pts[2];
256 }
257 }
258
add_cubic_segments(const SkPoint pts[4],SkPathPriv::FirstDirection dir,SegmentArray * segments)259 static inline void add_cubic_segments(const SkPoint pts[4],
260 SkPathPriv::FirstDirection dir,
261 SegmentArray* segments) {
262 SkSTArray<15, SkPoint, true> quads;
263 GrPathUtils::convertCubicToQuadsConstrainToTangents(pts, SK_Scalar1, dir, &quads);
264 int count = quads.count();
265 for (int q = 0; q < count; q += 3) {
266 add_quad_segment(&quads[q], segments);
267 }
268 }
269
get_segments(const SkPath & path,const SkMatrix & m,SegmentArray * segments,SkPoint * fanPt,int * vCount,int * iCount)270 static bool get_segments(const SkPath& path,
271 const SkMatrix& m,
272 SegmentArray* segments,
273 SkPoint* fanPt,
274 int* vCount,
275 int* iCount) {
276 SkPath::Iter iter(path, true);
277 // This renderer over-emphasizes very thin path regions. We use the distance
278 // to the path from the sample to compute coverage. Every pixel intersected
279 // by the path will be hit and the maximum distance is sqrt(2)/2. We don't
280 // notice that the sample may be close to a very thin area of the path and
281 // thus should be very light. This is particularly egregious for degenerate
282 // line paths. We detect paths that are very close to a line (zero area) and
283 // draw nothing.
284 DegenerateTestData degenerateData;
285 SkPathPriv::FirstDirection dir;
286 // get_direction can fail for some degenerate paths.
287 if (!get_direction(path, m, &dir)) {
288 return false;
289 }
290
291 for (;;) {
292 SkPoint pts[4];
293 SkPath::Verb verb = iter.next(pts, true, true);
294 switch (verb) {
295 case SkPath::kMove_Verb:
296 m.mapPoints(pts, 1);
297 update_degenerate_test(°enerateData, pts[0]);
298 break;
299 case SkPath::kLine_Verb: {
300 m.mapPoints(&pts[1], 1);
301 update_degenerate_test(°enerateData, pts[1]);
302 add_line_to_segment(pts[1], segments);
303 break;
304 }
305 case SkPath::kQuad_Verb:
306 m.mapPoints(pts, 3);
307 update_degenerate_test(°enerateData, pts[1]);
308 update_degenerate_test(°enerateData, pts[2]);
309 add_quad_segment(pts, segments);
310 break;
311 case SkPath::kConic_Verb: {
312 m.mapPoints(pts, 3);
313 SkScalar weight = iter.conicWeight();
314 SkAutoConicToQuads converter;
315 const SkPoint* quadPts = converter.computeQuads(pts, weight, 0.25f);
316 for (int i = 0; i < converter.countQuads(); ++i) {
317 update_degenerate_test(°enerateData, quadPts[2*i + 1]);
318 update_degenerate_test(°enerateData, quadPts[2*i + 2]);
319 add_quad_segment(quadPts + 2*i, segments);
320 }
321 break;
322 }
323 case SkPath::kCubic_Verb: {
324 m.mapPoints(pts, 4);
325 update_degenerate_test(°enerateData, pts[1]);
326 update_degenerate_test(°enerateData, pts[2]);
327 update_degenerate_test(°enerateData, pts[3]);
328 add_cubic_segments(pts, dir, segments);
329 break;
330 }
331 case SkPath::kDone_Verb:
332 if (degenerateData.isDegenerate()) {
333 return false;
334 } else {
335 return compute_vectors(segments, fanPt, dir, vCount, iCount);
336 }
337 default:
338 break;
339 }
340 }
341 }
342
343 struct Draw {
DrawDraw344 Draw() : fVertexCnt(0), fIndexCnt(0) {}
345 int fVertexCnt;
346 int fIndexCnt;
347 };
348
349 typedef SkTArray<Draw, true> DrawArray;
350
create_vertices(const SegmentArray & segments,const SkPoint & fanPt,const GrVertexColor & color,DrawArray * draws,GrVertexWriter & verts,uint16_t * idxs,size_t vertexStride)351 static void create_vertices(const SegmentArray& segments,
352 const SkPoint& fanPt,
353 const GrVertexColor& color,
354 DrawArray* draws,
355 GrVertexWriter& verts,
356 uint16_t* idxs,
357 size_t vertexStride) {
358 Draw* draw = &draws->push_back();
359 // alias just to make vert/index assignments easier to read.
360 int* v = &draw->fVertexCnt;
361 int* i = &draw->fIndexCnt;
362 const size_t uvOffset = sizeof(SkPoint) + color.size();
363
364 int count = segments.count();
365 for (int a = 0; a < count; ++a) {
366 const Segment& sega = segments[a];
367 int b = (a + 1) % count;
368 const Segment& segb = segments[b];
369
370 // Check whether adding the verts for this segment to the current draw would cause index
371 // values to overflow.
372 int vCount = 4;
373 if (Segment::kLine == segb.fType) {
374 vCount += 5;
375 } else {
376 vCount += 6;
377 }
378 if (draw->fVertexCnt + vCount > (1 << 16)) {
379 idxs += *i;
380 draw = &draws->push_back();
381 v = &draw->fVertexCnt;
382 i = &draw->fIndexCnt;
383 }
384
385 const SkScalar negOneDists[2] = { -SK_Scalar1, -SK_Scalar1 };
386
387 // FIXME: These tris are inset in the 1 unit arc around the corner
388 SkPoint p0 = sega.endPt();
389 // Position, Color, UV, D0, D1
390 verts.write(p0, color, SkPoint{0, 0}, negOneDists);
391 verts.write(p0 + sega.endNorm(), color, SkPoint{0, -SK_Scalar1}, negOneDists);
392 verts.write(p0 + segb.fMid, color, SkPoint{0, -SK_Scalar1}, negOneDists);
393 verts.write(p0 + segb.fNorms[0], color, SkPoint{0, -SK_Scalar1}, negOneDists);
394
395 idxs[*i + 0] = *v + 0;
396 idxs[*i + 1] = *v + 2;
397 idxs[*i + 2] = *v + 1;
398 idxs[*i + 3] = *v + 0;
399 idxs[*i + 4] = *v + 3;
400 idxs[*i + 5] = *v + 2;
401
402 *v += 4;
403 *i += 6;
404
405 if (Segment::kLine == segb.fType) {
406 // we draw the line edge as a degenerate quad (u is 0, v is the
407 // signed distance to the edge)
408 SkPoint v1Pos = sega.endPt();
409 SkPoint v2Pos = segb.fPts[0];
410 SkScalar dist = SkPointPriv::DistanceToLineBetween(fanPt, v1Pos, v2Pos);
411
412 verts.write(fanPt, color, SkPoint{0, dist}, negOneDists);
413 verts.write(v1Pos, color, SkPoint{0, 0}, negOneDists);
414 verts.write(v2Pos, color, SkPoint{0, 0}, negOneDists);
415 verts.write(v1Pos + segb.fNorms[0], color, SkPoint{0, -SK_Scalar1}, negOneDists);
416 verts.write(v2Pos + segb.fNorms[0], color, SkPoint{0, -SK_Scalar1}, negOneDists);
417
418 idxs[*i + 0] = *v + 3;
419 idxs[*i + 1] = *v + 1;
420 idxs[*i + 2] = *v + 2;
421
422 idxs[*i + 3] = *v + 4;
423 idxs[*i + 4] = *v + 3;
424 idxs[*i + 5] = *v + 2;
425
426 *i += 6;
427
428 // Draw the interior fan if it exists.
429 // TODO: Detect and combine colinear segments. This will ensure we catch every case
430 // with no interior, and that the resulting shared edge uses the same endpoints.
431 if (count >= 3) {
432 idxs[*i + 0] = *v + 0;
433 idxs[*i + 1] = *v + 2;
434 idxs[*i + 2] = *v + 1;
435
436 *i += 3;
437 }
438
439 *v += 5;
440 } else {
441 void* quadVertsBegin = verts.fPtr;
442
443 SkPoint qpts[] = {sega.endPt(), segb.fPts[0], segb.fPts[1]};
444
445 SkScalar c0 = segb.fNorms[0].dot(qpts[0]);
446 SkScalar c1 = segb.fNorms[1].dot(qpts[2]);
447 GrVertexWriter::Skip<SkPoint> skipUVs;
448
449 verts.write(fanPt,
450 color, skipUVs,
451 -segb.fNorms[0].dot(fanPt) + c0,
452 -segb.fNorms[1].dot(fanPt) + c1);
453
454 verts.write(qpts[0],
455 color, skipUVs,
456 0.0f,
457 -segb.fNorms[1].dot(qpts[0]) + c1);
458
459 verts.write(qpts[2],
460 color, skipUVs,
461 -segb.fNorms[0].dot(qpts[2]) + c0,
462 0.0f);
463
464 verts.write(qpts[0] + segb.fNorms[0],
465 color, skipUVs,
466 -SK_ScalarMax/100,
467 -SK_ScalarMax/100);
468
469 verts.write(qpts[2] + segb.fNorms[1],
470 color, skipUVs,
471 -SK_ScalarMax/100,
472 -SK_ScalarMax/100);
473
474 SkVector midVec = segb.fNorms[0] + segb.fNorms[1];
475 midVec.normalize();
476
477 verts.write(qpts[1] + midVec,
478 color, skipUVs,
479 -SK_ScalarMax/100,
480 -SK_ScalarMax/100);
481
482 GrPathUtils::QuadUVMatrix toUV(qpts);
483 toUV.apply(quadVertsBegin, 6, vertexStride, uvOffset);
484
485 idxs[*i + 0] = *v + 3;
486 idxs[*i + 1] = *v + 1;
487 idxs[*i + 2] = *v + 2;
488 idxs[*i + 3] = *v + 4;
489 idxs[*i + 4] = *v + 3;
490 idxs[*i + 5] = *v + 2;
491
492 idxs[*i + 6] = *v + 5;
493 idxs[*i + 7] = *v + 3;
494 idxs[*i + 8] = *v + 4;
495
496 *i += 9;
497
498 // Draw the interior fan if it exists.
499 // TODO: Detect and combine colinear segments. This will ensure we catch every case
500 // with no interior, and that the resulting shared edge uses the same endpoints.
501 if (count >= 3) {
502 idxs[*i + 0] = *v + 0;
503 idxs[*i + 1] = *v + 2;
504 idxs[*i + 2] = *v + 1;
505
506 *i += 3;
507 }
508
509 *v += 6;
510 }
511 }
512 }
513
514 ///////////////////////////////////////////////////////////////////////////////
515
516 /*
517 * Quadratic specified by 0=u^2-v canonical coords. u and v are the first
518 * two components of the vertex attribute. Coverage is based on signed
519 * distance with negative being inside, positive outside. The edge is specified in
520 * window space (y-down). If either the third or fourth component of the interpolated
521 * vertex coord is > 0 then the pixel is considered outside the edge. This is used to
522 * attempt to trim to a portion of the infinite quad.
523 * Requires shader derivative instruction support.
524 */
525
526 class QuadEdgeEffect : public GrGeometryProcessor {
527 public:
Make(const SkMatrix & localMatrix,bool usesLocalCoords,bool wideColor)528 static sk_sp<GrGeometryProcessor> Make(const SkMatrix& localMatrix, bool usesLocalCoords,
529 bool wideColor) {
530 return sk_sp<GrGeometryProcessor>(
531 new QuadEdgeEffect(localMatrix, usesLocalCoords, wideColor));
532 }
533
~QuadEdgeEffect()534 ~QuadEdgeEffect() override {}
535
name() const536 const char* name() const override { return "QuadEdge"; }
537
538 class GLSLProcessor : public GrGLSLGeometryProcessor {
539 public:
GLSLProcessor()540 GLSLProcessor() {}
541
onEmitCode(EmitArgs & args,GrGPArgs * gpArgs)542 void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
543 const QuadEdgeEffect& qe = args.fGP.cast<QuadEdgeEffect>();
544 GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
545 GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
546 GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
547
548 // emit attributes
549 varyingHandler->emitAttributes(qe);
550
551 GrGLSLVarying v(kHalf4_GrSLType);
552 varyingHandler->addVarying("QuadEdge", &v);
553 vertBuilder->codeAppendf("%s = %s;", v.vsOut(), qe.fInQuadEdge.name());
554
555 // Setup pass through color
556 varyingHandler->addPassThroughAttribute(qe.fInColor, args.fOutputColor);
557
558 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
559
560 // Setup position
561 this->writeOutputPosition(vertBuilder, gpArgs, qe.fInPosition.name());
562
563 // emit transforms
564 this->emitTransforms(vertBuilder,
565 varyingHandler,
566 uniformHandler,
567 qe.fInPosition.asShaderVar(),
568 qe.fLocalMatrix,
569 args.fFPCoordTransformHandler);
570
571 fragBuilder->codeAppendf("half edgeAlpha;");
572
573 // keep the derivative instructions outside the conditional
574 fragBuilder->codeAppendf("half2 duvdx = dFdx(%s.xy);", v.fsIn());
575 fragBuilder->codeAppendf("half2 duvdy = dFdy(%s.xy);", v.fsIn());
576 fragBuilder->codeAppendf("if (%s.z > 0.0 && %s.w > 0.0) {", v.fsIn(), v.fsIn());
577 // today we know z and w are in device space. We could use derivatives
578 fragBuilder->codeAppendf("edgeAlpha = min(min(%s.z, %s.w) + 0.5, 1.0);", v.fsIn(),
579 v.fsIn());
580 fragBuilder->codeAppendf ("} else {");
581 fragBuilder->codeAppendf("half2 gF = half2(2.0*%s.x*duvdx.x - duvdx.y,"
582 " 2.0*%s.x*duvdy.x - duvdy.y);",
583 v.fsIn(), v.fsIn());
584 fragBuilder->codeAppendf("edgeAlpha = (%s.x*%s.x - %s.y);", v.fsIn(), v.fsIn(),
585 v.fsIn());
586 fragBuilder->codeAppendf("edgeAlpha = "
587 "saturate(0.5 - edgeAlpha / length(gF));}");
588
589 fragBuilder->codeAppendf("%s = half4(edgeAlpha);", args.fOutputCoverage);
590 }
591
GenKey(const GrGeometryProcessor & gp,const GrShaderCaps &,GrProcessorKeyBuilder * b)592 static inline void GenKey(const GrGeometryProcessor& gp,
593 const GrShaderCaps&,
594 GrProcessorKeyBuilder* b) {
595 const QuadEdgeEffect& qee = gp.cast<QuadEdgeEffect>();
596 b->add32(SkToBool(qee.fUsesLocalCoords && qee.fLocalMatrix.hasPerspective()));
597 }
598
setData(const GrGLSLProgramDataManager & pdman,const GrPrimitiveProcessor & gp,FPCoordTransformIter && transformIter)599 void setData(const GrGLSLProgramDataManager& pdman,
600 const GrPrimitiveProcessor& gp,
601 FPCoordTransformIter&& transformIter) override {
602 const QuadEdgeEffect& qe = gp.cast<QuadEdgeEffect>();
603 this->setTransformDataHelper(qe.fLocalMatrix, pdman, &transformIter);
604 }
605
606 private:
607 typedef GrGLSLGeometryProcessor INHERITED;
608 };
609
getGLSLProcessorKey(const GrShaderCaps & caps,GrProcessorKeyBuilder * b) const610 void getGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const override {
611 GLSLProcessor::GenKey(*this, caps, b);
612 }
613
createGLSLInstance(const GrShaderCaps &) const614 GrGLSLPrimitiveProcessor* createGLSLInstance(const GrShaderCaps&) const override {
615 return new GLSLProcessor();
616 }
617
618 private:
QuadEdgeEffect(const SkMatrix & localMatrix,bool usesLocalCoords,bool wideColor)619 QuadEdgeEffect(const SkMatrix& localMatrix, bool usesLocalCoords, bool wideColor)
620 : INHERITED(kQuadEdgeEffect_ClassID)
621 , fLocalMatrix(localMatrix)
622 , fUsesLocalCoords(usesLocalCoords) {
623 fInPosition = {"inPosition", kFloat2_GrVertexAttribType, kFloat2_GrSLType};
624 fInColor = MakeColorAttribute("inColor", wideColor);
625 fInQuadEdge = {"inQuadEdge", kFloat4_GrVertexAttribType, kHalf4_GrSLType};
626 this->setVertexAttributes(&fInPosition, 3);
627 }
628
629 Attribute fInPosition;
630 Attribute fInColor;
631 Attribute fInQuadEdge;
632
633 SkMatrix fLocalMatrix;
634 bool fUsesLocalCoords;
635
636 GR_DECLARE_GEOMETRY_PROCESSOR_TEST
637
638 typedef GrGeometryProcessor INHERITED;
639 };
640
641 GR_DEFINE_GEOMETRY_PROCESSOR_TEST(QuadEdgeEffect);
642
643 #if GR_TEST_UTILS
TestCreate(GrProcessorTestData * d)644 sk_sp<GrGeometryProcessor> QuadEdgeEffect::TestCreate(GrProcessorTestData* d) {
645 // Doesn't work without derivative instructions.
646 return d->caps()->shaderCaps()->shaderDerivativeSupport()
647 ? QuadEdgeEffect::Make(GrTest::TestMatrix(d->fRandom), d->fRandom->nextBool(),
648 d->fRandom->nextBool())
649 : nullptr;
650 }
651 #endif
652
653 ///////////////////////////////////////////////////////////////////////////////
654
655 GrPathRenderer::CanDrawPath
onCanDrawPath(const CanDrawPathArgs & args) const656 GrAAConvexPathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
657 if (args.fCaps->shaderCaps()->shaderDerivativeSupport() &&
658 (GrAAType::kCoverage == args.fAAType) && args.fShape->style().isSimpleFill() &&
659 !args.fShape->inverseFilled() && args.fShape->knownToBeConvex()) {
660 return CanDrawPath::kYes;
661 }
662 return CanDrawPath::kNo;
663 }
664
665 namespace {
666
667 class AAConvexPathOp final : public GrMeshDrawOp {
668 private:
669 using Helper = GrSimpleMeshDrawOpHelperWithStencil;
670
671 public:
672 DEFINE_OP_CLASS_ID
673
Make(GrContext * context,GrPaint && paint,const SkMatrix & viewMatrix,const SkPath & path,const GrUserStencilSettings * stencilSettings)674 static std::unique_ptr<GrDrawOp> Make(GrContext* context,
675 GrPaint&& paint,
676 const SkMatrix& viewMatrix,
677 const SkPath& path,
678 const GrUserStencilSettings* stencilSettings) {
679 return Helper::FactoryHelper<AAConvexPathOp>(context, std::move(paint), viewMatrix, path,
680 stencilSettings);
681 }
682
AAConvexPathOp(const Helper::MakeArgs & helperArgs,const SkPMColor4f & color,const SkMatrix & viewMatrix,const SkPath & path,const GrUserStencilSettings * stencilSettings)683 AAConvexPathOp(const Helper::MakeArgs& helperArgs, const SkPMColor4f& color,
684 const SkMatrix& viewMatrix, const SkPath& path,
685 const GrUserStencilSettings* stencilSettings)
686 : INHERITED(ClassID()), fHelper(helperArgs, GrAAType::kCoverage, stencilSettings) {
687 fPaths.emplace_back(PathData{viewMatrix, path, color});
688 this->setTransformedBounds(path.getBounds(), viewMatrix, HasAABloat::kYes, IsZeroArea::kNo);
689 fWideColor = !SkPMColor4fFitsInBytes(color);
690 }
691
name() const692 const char* name() const override { return "AAConvexPathOp"; }
693
visitProxies(const VisitProxyFunc & func,VisitorType) const694 void visitProxies(const VisitProxyFunc& func, VisitorType) const override {
695 fHelper.visitProxies(func);
696 }
697
698 #ifdef SK_DEBUG
dumpInfo() const699 SkString dumpInfo() const override {
700 SkString string;
701 string.appendf("Count: %d\n", fPaths.count());
702 string += fHelper.dumpInfo();
703 string += INHERITED::dumpInfo();
704 return string;
705 }
706 #endif
707
fixedFunctionFlags() const708 FixedFunctionFlags fixedFunctionFlags() const override { return fHelper.fixedFunctionFlags(); }
709
finalize(const GrCaps & caps,const GrAppliedClip * clip)710 GrProcessorSet::Analysis finalize(const GrCaps& caps, const GrAppliedClip* clip) override {
711 return fHelper.finalizeProcessors(caps, clip, GrProcessorAnalysisCoverage::kSingleChannel,
712 &fPaths.back().fColor);
713 }
714
715 private:
onPrepareDraws(Target * target)716 void onPrepareDraws(Target* target) override {
717 auto pipe = fHelper.makePipeline(target);
718 int instanceCount = fPaths.count();
719
720 SkMatrix invert;
721 if (fHelper.usesLocalCoords() && !fPaths.back().fViewMatrix.invert(&invert)) {
722 return;
723 }
724
725 // Setup GrGeometryProcessor
726 sk_sp<GrGeometryProcessor> quadProcessor(
727 QuadEdgeEffect::Make(invert, fHelper.usesLocalCoords(), fWideColor));
728 const size_t kVertexStride = quadProcessor->vertexStride();
729
730 // TODO generate all segments for all paths and use one vertex buffer
731 for (int i = 0; i < instanceCount; i++) {
732 const PathData& args = fPaths[i];
733
734 // We use the fact that SkPath::transform path does subdivision based on
735 // perspective. Otherwise, we apply the view matrix when copying to the
736 // segment representation.
737 const SkMatrix* viewMatrix = &args.fViewMatrix;
738
739 // We avoid initializing the path unless we have to
740 const SkPath* pathPtr = &args.fPath;
741 SkTLazy<SkPath> tmpPath;
742 if (viewMatrix->hasPerspective()) {
743 SkPath* tmpPathPtr = tmpPath.init(*pathPtr);
744 tmpPathPtr->setIsVolatile(true);
745 tmpPathPtr->transform(*viewMatrix);
746 viewMatrix = &SkMatrix::I();
747 pathPtr = tmpPathPtr;
748 }
749
750 int vertexCount;
751 int indexCount;
752 enum {
753 kPreallocSegmentCnt = 512 / sizeof(Segment),
754 kPreallocDrawCnt = 4,
755 };
756 SkSTArray<kPreallocSegmentCnt, Segment, true> segments;
757 SkPoint fanPt;
758
759 if (!get_segments(*pathPtr, *viewMatrix, &segments, &fanPt, &vertexCount,
760 &indexCount)) {
761 continue;
762 }
763
764 sk_sp<const GrBuffer> vertexBuffer;
765 int firstVertex;
766
767 GrVertexWriter verts{target->makeVertexSpace(kVertexStride, vertexCount,
768 &vertexBuffer, &firstVertex)};
769
770 if (!verts.fPtr) {
771 SkDebugf("Could not allocate vertices\n");
772 return;
773 }
774
775 sk_sp<const GrBuffer> indexBuffer;
776 int firstIndex;
777
778 uint16_t *idxs = target->makeIndexSpace(indexCount, &indexBuffer, &firstIndex);
779 if (!idxs) {
780 SkDebugf("Could not allocate indices\n");
781 return;
782 }
783
784 SkSTArray<kPreallocDrawCnt, Draw, true> draws;
785 GrVertexColor color(args.fColor, fWideColor);
786 create_vertices(segments, fanPt, color, &draws, verts, idxs, kVertexStride);
787
788 GrMesh* meshes = target->allocMeshes(draws.count());
789 for (int j = 0; j < draws.count(); ++j) {
790 const Draw& draw = draws[j];
791 meshes[j].setPrimitiveType(GrPrimitiveType::kTriangles);
792 meshes[j].setIndexed(indexBuffer, draw.fIndexCnt, firstIndex, 0,
793 draw.fVertexCnt - 1, GrPrimitiveRestart::kNo);
794 meshes[j].setVertexData(vertexBuffer, firstVertex);
795 firstIndex += draw.fIndexCnt;
796 firstVertex += draw.fVertexCnt;
797 }
798 target->draw(quadProcessor, pipe.fPipeline, pipe.fFixedDynamicState, nullptr, meshes,
799 draws.count());
800 }
801 }
802
onCombineIfPossible(GrOp * t,const GrCaps & caps)803 CombineResult onCombineIfPossible(GrOp* t, const GrCaps& caps) override {
804 AAConvexPathOp* that = t->cast<AAConvexPathOp>();
805 if (!fHelper.isCompatible(that->fHelper, caps, this->bounds(), that->bounds())) {
806 return CombineResult::kCannotCombine;
807 }
808 if (fHelper.usesLocalCoords() &&
809 !fPaths[0].fViewMatrix.cheapEqualTo(that->fPaths[0].fViewMatrix)) {
810 return CombineResult::kCannotCombine;
811 }
812
813 fPaths.push_back_n(that->fPaths.count(), that->fPaths.begin());
814 fWideColor |= that->fWideColor;
815 return CombineResult::kMerged;
816 }
817
818 struct PathData {
819 SkMatrix fViewMatrix;
820 SkPath fPath;
821 SkPMColor4f fColor;
822 };
823
824 Helper fHelper;
825 SkSTArray<1, PathData, true> fPaths;
826 bool fWideColor;
827
828 typedef GrMeshDrawOp INHERITED;
829 };
830
831 } // anonymous namespace
832
onDrawPath(const DrawPathArgs & args)833 bool GrAAConvexPathRenderer::onDrawPath(const DrawPathArgs& args) {
834 GR_AUDIT_TRAIL_AUTO_FRAME(args.fRenderTargetContext->auditTrail(),
835 "GrAAConvexPathRenderer::onDrawPath");
836 SkASSERT(GrFSAAType::kUnifiedMSAA != args.fRenderTargetContext->fsaaType());
837 SkASSERT(!args.fShape->isEmpty());
838
839 SkPath path;
840 args.fShape->asPath(&path);
841
842 std::unique_ptr<GrDrawOp> op = AAConvexPathOp::Make(args.fContext, std::move(args.fPaint),
843 *args.fViewMatrix,
844 path, args.fUserStencilSettings);
845 args.fRenderTargetContext->addDrawOp(*args.fClip, std::move(op));
846 return true;
847 }
848
849 ///////////////////////////////////////////////////////////////////////////////////////////////////
850
851 #if GR_TEST_UTILS
852
GR_DRAW_OP_TEST_DEFINE(AAConvexPathOp)853 GR_DRAW_OP_TEST_DEFINE(AAConvexPathOp) {
854 SkMatrix viewMatrix = GrTest::TestMatrixInvertible(random);
855 SkPath path = GrTest::TestPathConvex(random);
856 const GrUserStencilSettings* stencilSettings = GrGetRandomStencil(random, context);
857 return AAConvexPathOp::Make(context, std::move(paint), viewMatrix, path, stencilSettings);
858 }
859
860 #endif
861