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 "src/gpu/ops/AAHairLinePathRenderer.h"
9
10#include "include/core/SkPoint3.h"
11#include "include/private/SkTemplates.h"
12#include "src/core/SkGeometry.h"
13#include "src/core/SkMatrixPriv.h"
14#include "src/core/SkPointPriv.h"
15#include "src/core/SkRectPriv.h"
16#include "src/core/SkStroke.h"
17#include "src/gpu/GrAuditTrail.h"
18#include "src/gpu/GrBuffer.h"
19#include "src/gpu/GrCaps.h"
20#include "src/gpu/GrDefaultGeoProcFactory.h"
21#include "src/gpu/GrDrawOpTest.h"
22#include "src/gpu/GrOpFlushState.h"
23#include "src/gpu/GrProcessor.h"
24#include "src/gpu/GrProgramInfo.h"
25#include "src/gpu/GrResourceProvider.h"
26#include "src/gpu/GrStyle.h"
27#include "src/gpu/GrUtil.h"
28#include "src/gpu/effects/GrBezierEffect.h"
29#include "src/gpu/geometry/GrPathUtils.h"
30#include "src/gpu/geometry/GrStyledShape.h"
31#include "src/gpu/ops/GrMeshDrawOp.h"
32#include "src/gpu/ops/GrSimpleMeshDrawOpHelperWithStencil.h"
33#include "src/gpu/v1/SurfaceDrawContext_v1.h"
34
35#define PREALLOC_PTARRAY(N) SkSTArray<(N),SkPoint, true>
36
37using PtArray = SkTArray<SkPoint, true>;
38using IntArray = SkTArray<int, true>;
39using FloatArray = SkTArray<float, true>;
40
41namespace {
42
43// quadratics are rendered as 5-sided polys in order to bound the
44// AA stroke around the center-curve. See comments in push_quad_index_buffer and
45// bloat_quad. Quadratics and conics share an index buffer
46
47// lines are rendered as:
48//      *______________*
49//      |\ -_______   /|
50//      | \        \ / |
51//      |  *--------*  |
52//      | /  ______/ \ |
53//      */_-__________\*
54// For: 6 vertices and 18 indices (for 6 triangles)
55
56// Each quadratic is rendered as a five sided polygon. This poly bounds
57// the quadratic's bounding triangle but has been expanded so that the
58// 1-pixel wide area around the curve is inside the poly.
59// If a,b,c are the original control points then the poly a0,b0,c0,c1,a1
60// that is rendered would look like this:
61//              b0
62//              b
63//
64//     a0              c0
65//      a            c
66//       a1       c1
67// Each is drawn as three triangles ((a0,a1,b0), (b0,c1,c0), (a1,c1,b0))
68// specified by these 9 indices:
69static const uint16_t kQuadIdxBufPattern[] = {
70    0, 1, 2,
71    2, 4, 3,
72    1, 4, 2
73};
74
75static const int kIdxsPerQuad = SK_ARRAY_COUNT(kQuadIdxBufPattern);
76static const int kQuadNumVertices = 5;
77static const int kQuadsNumInIdxBuffer = 256;
78GR_DECLARE_STATIC_UNIQUE_KEY(gQuadsIndexBufferKey);
79
80sk_sp<const GrBuffer> get_quads_index_buffer(GrResourceProvider* resourceProvider) {
81    GR_DEFINE_STATIC_UNIQUE_KEY(gQuadsIndexBufferKey);
82    return resourceProvider->findOrCreatePatternedIndexBuffer(
83        kQuadIdxBufPattern, kIdxsPerQuad, kQuadsNumInIdxBuffer, kQuadNumVertices,
84        gQuadsIndexBufferKey);
85}
86
87
88// Each line segment is rendered as two quads and two triangles.
89// p0 and p1 have alpha = 1 while all other points have alpha = 0.
90// The four external points are offset 1 pixel perpendicular to the
91// line and half a pixel parallel to the line.
92//
93// p4                  p5
94//      p0         p1
95// p2                  p3
96//
97// Each is drawn as six triangles specified by these 18 indices:
98
99static const uint16_t kLineSegIdxBufPattern[] = {
100    0, 1, 3,
101    0, 3, 2,
102    0, 4, 5,
103    0, 5, 1,
104    0, 2, 4,
105    1, 5, 3
106};
107
108static const int kIdxsPerLineSeg = SK_ARRAY_COUNT(kLineSegIdxBufPattern);
109static const int kLineSegNumVertices = 6;
110static const int kLineSegsNumInIdxBuffer = 256;
111
112GR_DECLARE_STATIC_UNIQUE_KEY(gLinesIndexBufferKey);
113
114sk_sp<const GrBuffer> get_lines_index_buffer(GrResourceProvider* resourceProvider) {
115    GR_DEFINE_STATIC_UNIQUE_KEY(gLinesIndexBufferKey);
116    return resourceProvider->findOrCreatePatternedIndexBuffer(
117        kLineSegIdxBufPattern, kIdxsPerLineSeg,  kLineSegsNumInIdxBuffer, kLineSegNumVertices,
118        gLinesIndexBufferKey);
119}
120
121// Takes 178th time of logf on Z600 / VC2010
122int get_float_exp(float x) {
123    static_assert(sizeof(int) == sizeof(float));
124#ifdef SK_DEBUG
125    static bool tested;
126    if (!tested) {
127        tested = true;
128        SkASSERT(get_float_exp(0.25f) == -2);
129        SkASSERT(get_float_exp(0.3f) == -2);
130        SkASSERT(get_float_exp(0.5f) == -1);
131        SkASSERT(get_float_exp(1.f) == 0);
132        SkASSERT(get_float_exp(2.f) == 1);
133        SkASSERT(get_float_exp(2.5f) == 1);
134        SkASSERT(get_float_exp(8.f) == 3);
135        SkASSERT(get_float_exp(100.f) == 6);
136        SkASSERT(get_float_exp(1000.f) == 9);
137        SkASSERT(get_float_exp(1024.f) == 10);
138        SkASSERT(get_float_exp(3000000.f) == 21);
139    }
140#endif
141    const int* iptr = (const int*)&x;
142    return (((*iptr) & 0x7f800000) >> 23) - 127;
143}
144
145// Uses the max curvature function for quads to estimate
146// where to chop the conic. If the max curvature is not
147// found along the curve segment it will return 1 and
148// dst[0] is the original conic. If it returns 2 the dst[0]
149// and dst[1] are the two new conics.
150int split_conic(const SkPoint src[3], SkConic dst[2], const SkScalar weight) {
151    SkScalar t = SkFindQuadMaxCurvature(src);
152    if (t == 0 || t == 1) {
153        if (dst) {
154            dst[0].set(src, weight);
155        }
156        return 1;
157    } else {
158        if (dst) {
159            SkConic conic;
160            conic.set(src, weight);
161            if (!conic.chopAt(t, dst)) {
162                dst[0].set(src, weight);
163                return 1;
164            }
165        }
166        return 2;
167    }
168}
169
170// Calls split_conic on the entire conic and then once more on each subsection.
171// Most cases will result in either 1 conic (chop point is not within t range)
172// or 3 points (split once and then one subsection is split again).
173int chop_conic(const SkPoint src[3], SkConic dst[4], const SkScalar weight) {
174    SkConic dstTemp[2];
175    int conicCnt = split_conic(src, dstTemp, weight);
176    if (2 == conicCnt) {
177        int conicCnt2 = split_conic(dstTemp[0].fPts, dst, dstTemp[0].fW);
178        conicCnt = conicCnt2 + split_conic(dstTemp[1].fPts, &dst[conicCnt2], dstTemp[1].fW);
179    } else {
180        dst[0] = dstTemp[0];
181    }
182    return conicCnt;
183}
184
185// returns 0 if quad/conic is degen or close to it
186// in this case approx the path with lines
187// otherwise returns 1
188int is_degen_quad_or_conic(const SkPoint p[3], SkScalar* dsqd) {
189    static const SkScalar gDegenerateToLineTol = GrPathUtils::kDefaultTolerance;
190    static const SkScalar gDegenerateToLineTolSqd =
191        gDegenerateToLineTol * gDegenerateToLineTol;
192
193    if (SkPointPriv::DistanceToSqd(p[0], p[1]) < gDegenerateToLineTolSqd ||
194        SkPointPriv::DistanceToSqd(p[1], p[2]) < gDegenerateToLineTolSqd) {
195        return 1;
196    }
197
198    *dsqd = SkPointPriv::DistanceToLineBetweenSqd(p[1], p[0], p[2]);
199    if (*dsqd < gDegenerateToLineTolSqd) {
200        return 1;
201    }
202
203    if (SkPointPriv::DistanceToLineBetweenSqd(p[2], p[1], p[0]) < gDegenerateToLineTolSqd) {
204        return 1;
205    }
206    return 0;
207}
208
209int is_degen_quad_or_conic(const SkPoint p[3]) {
210    SkScalar dsqd;
211    return is_degen_quad_or_conic(p, &dsqd);
212}
213
214// we subdivide the quads to avoid huge overfill
215// if it returns -1 then should be drawn as lines
216int num_quad_subdivs(const SkPoint p[3]) {
217    SkScalar dsqd;
218    if (is_degen_quad_or_conic(p, &dsqd)) {
219        return -1;
220    }
221
222    // tolerance of triangle height in pixels
223    // tuned on windows  Quadro FX 380 / Z600
224    // trade off of fill vs cpu time on verts
225    // maybe different when do this using gpu (geo or tess shaders)
226    static const SkScalar gSubdivTol = 175 * SK_Scalar1;
227
228    if (dsqd <= gSubdivTol * gSubdivTol) {
229        return 0;
230    } else {
231        static const int kMaxSub = 4;
232        // subdividing the quad reduces d by 4. so we want x = log4(d/tol)
233        // = log4(d*d/tol*tol)/2
234        // = log2(d*d/tol*tol)
235
236        // +1 since we're ignoring the mantissa contribution.
237        int log = get_float_exp(dsqd/(gSubdivTol*gSubdivTol)) + 1;
238        log = std::min(std::max(0, log), kMaxSub);
239        return log;
240    }
241}
242
243/**
244 * Generates the lines and quads to be rendered. Lines are always recorded in
245 * device space. We will do a device space bloat to account for the 1pixel
246 * thickness.
247 * Quads are recorded in device space unless m contains
248 * perspective, then in they are in src space. We do this because we will
249 * subdivide large quads to reduce over-fill. This subdivision has to be
250 * performed before applying the perspective matrix.
251 */
252int gather_lines_and_quads(const SkPath& path,
253                           const SkMatrix& m,
254                           const SkIRect& devClipBounds,
255                           SkScalar capLength,
256                           bool convertConicsToQuads,
257                           PtArray* lines,
258                           PtArray* quads,
259                           PtArray* conics,
260                           IntArray* quadSubdivCnts,
261                           FloatArray* conicWeights) {
262    SkPath::Iter iter(path, false);
263
264    int totalQuadCount = 0;
265    SkRect bounds;
266    SkIRect ibounds;
267
268    bool persp = m.hasPerspective();
269
270    // Whenever a degenerate, zero-length contour is encountered, this code will insert a
271    // 'capLength' x-aligned line segment. Since this is rendering hairlines it is hoped this will
272    // suffice for AA square & circle capping.
273    int verbsInContour = 0; // Does not count moves
274    bool seenZeroLengthVerb = false;
275    SkPoint zeroVerbPt;
276
277    // Adds a quad that has already been chopped to the list and checks for quads that are close to
278    // lines. Also does a bounding box check. It takes points that are in src space and device
279    // space. The src points are only required if the view matrix has perspective.
280    auto addChoppedQuad = [&](const SkPoint srcPts[3], const SkPoint devPts[4],
281                              bool isContourStart) {
282        SkRect bounds;
283        SkIRect ibounds;
284        bounds.setBounds(devPts, 3);
285        bounds.outset(SK_Scalar1, SK_Scalar1);
286        bounds.roundOut(&ibounds);
287        // We only need the src space space pts when not in perspective.
288        SkASSERT(srcPts || !persp);
289        if (SkIRect::Intersects(devClipBounds, ibounds)) {
290            int subdiv = num_quad_subdivs(devPts);
291            SkASSERT(subdiv >= -1);
292            if (-1 == subdiv) {
293                SkPoint* pts = lines->push_back_n(4);
294                pts[0] = devPts[0];
295                pts[1] = devPts[1];
296                pts[2] = devPts[1];
297                pts[3] = devPts[2];
298                if (isContourStart && pts[0] == pts[1] && pts[2] == pts[3]) {
299                    seenZeroLengthVerb = true;
300                    zeroVerbPt = pts[0];
301                }
302            } else {
303                // when in perspective keep quads in src space
304                const SkPoint* qPts = persp ? srcPts : devPts;
305                SkPoint* pts = quads->push_back_n(3);
306                pts[0] = qPts[0];
307                pts[1] = qPts[1];
308                pts[2] = qPts[2];
309                quadSubdivCnts->push_back() = subdiv;
310                totalQuadCount += 1 << subdiv;
311            }
312        }
313    };
314
315    // Applies the view matrix to quad src points and calls the above helper.
316    auto addSrcChoppedQuad = [&](const SkPoint srcSpaceQuadPts[3], bool isContourStart) {
317        SkPoint devPts[3];
318        m.mapPoints(devPts, srcSpaceQuadPts, 3);
319        addChoppedQuad(srcSpaceQuadPts, devPts, isContourStart);
320    };
321
322    for (;;) {
323        SkPoint pathPts[4];
324        SkPath::Verb verb = iter.next(pathPts);
325        switch (verb) {
326            case SkPath::kConic_Verb:
327                if (convertConicsToQuads) {
328                    SkScalar weight = iter.conicWeight();
329                    SkAutoConicToQuads converter;
330                    const SkPoint* quadPts = converter.computeQuads(pathPts, weight, 0.25f);
331                    for (int i = 0; i < converter.countQuads(); ++i) {
332                        addSrcChoppedQuad(quadPts + 2 * i, !verbsInContour && 0 == i);
333                    }
334                } else {
335                    SkConic dst[4];
336                    // We chop the conics to create tighter clipping to hide error
337                    // that appears near max curvature of very thin conics. Thin
338                    // hyperbolas with high weight still show error.
339                    int conicCnt = chop_conic(pathPts, dst, iter.conicWeight());
340                    for (int i = 0; i < conicCnt; ++i) {
341                        SkPoint devPts[4];
342                        SkPoint* chopPnts = dst[i].fPts;
343                        m.mapPoints(devPts, chopPnts, 3);
344                        bounds.setBounds(devPts, 3);
345                        bounds.outset(SK_Scalar1, SK_Scalar1);
346                        bounds.roundOut(&ibounds);
347                        if (SkIRect::Intersects(devClipBounds, ibounds)) {
348                            if (is_degen_quad_or_conic(devPts)) {
349                                SkPoint* pts = lines->push_back_n(4);
350                                pts[0] = devPts[0];
351                                pts[1] = devPts[1];
352                                pts[2] = devPts[1];
353                                pts[3] = devPts[2];
354                                if (verbsInContour == 0 && i == 0 && pts[0] == pts[1] &&
355                                    pts[2] == pts[3]) {
356                                    seenZeroLengthVerb = true;
357                                    zeroVerbPt = pts[0];
358                                }
359                            } else {
360                                // when in perspective keep conics in src space
361                                SkPoint* cPts = persp ? chopPnts : devPts;
362                                SkPoint* pts = conics->push_back_n(3);
363                                pts[0] = cPts[0];
364                                pts[1] = cPts[1];
365                                pts[2] = cPts[2];
366                                conicWeights->push_back() = dst[i].fW;
367                            }
368                        }
369                    }
370                }
371                verbsInContour++;
372                break;
373            case SkPath::kMove_Verb:
374                // New contour (and last one was unclosed). If it was just a zero length drawing
375                // operation, and we're supposed to draw caps, then add a tiny line.
376                if (seenZeroLengthVerb && verbsInContour == 1 && capLength > 0) {
377                    SkPoint* pts = lines->push_back_n(2);
378                    pts[0] = SkPoint::Make(zeroVerbPt.fX - capLength, zeroVerbPt.fY);
379                    pts[1] = SkPoint::Make(zeroVerbPt.fX + capLength, zeroVerbPt.fY);
380                }
381                verbsInContour = 0;
382                seenZeroLengthVerb = false;
383                break;
384            case SkPath::kLine_Verb: {
385                SkPoint devPts[2];
386                m.mapPoints(devPts, pathPts, 2);
387                bounds.setBounds(devPts, 2);
388                bounds.outset(SK_Scalar1, SK_Scalar1);
389                bounds.roundOut(&ibounds);
390                if (SkIRect::Intersects(devClipBounds, ibounds)) {
391                    SkPoint* pts = lines->push_back_n(2);
392                    pts[0] = devPts[0];
393                    pts[1] = devPts[1];
394                    if (verbsInContour == 0 && pts[0] == pts[1]) {
395                        seenZeroLengthVerb = true;
396                        zeroVerbPt = pts[0];
397                    }
398                }
399                verbsInContour++;
400                break;
401            }
402            case SkPath::kQuad_Verb: {
403                SkPoint choppedPts[5];
404                // Chopping the quad helps when the quad is either degenerate or nearly degenerate.
405                // When it is degenerate it allows the approximation with lines to work since the
406                // chop point (if there is one) will be at the parabola's vertex. In the nearly
407                // degenerate the QuadUVMatrix computed for the points is almost singular which
408                // can cause rendering artifacts.
409                int n = SkChopQuadAtMaxCurvature(pathPts, choppedPts);
410                for (int i = 0; i < n; ++i) {
411                    addSrcChoppedQuad(choppedPts + i * 2, !verbsInContour && 0 == i);
412                }
413                verbsInContour++;
414                break;
415            }
416            case SkPath::kCubic_Verb: {
417                SkPoint devPts[4];
418                m.mapPoints(devPts, pathPts, 4);
419                bounds.setBounds(devPts, 4);
420                bounds.outset(SK_Scalar1, SK_Scalar1);
421                bounds.roundOut(&ibounds);
422                if (SkIRect::Intersects(devClipBounds, ibounds)) {
423                    PREALLOC_PTARRAY(32) q;
424                    // We convert cubics to quadratics (for now).
425                    // In perspective have to do conversion in src space.
426                    if (persp) {
427                        SkScalar tolScale =
428                            GrPathUtils::scaleToleranceToSrc(SK_Scalar1, m, path.getBounds());
429                        GrPathUtils::convertCubicToQuads(pathPts, tolScale, &q);
430                    } else {
431                        GrPathUtils::convertCubicToQuads(devPts, SK_Scalar1, &q);
432                    }
433                    for (int i = 0; i < q.count(); i += 3) {
434                        if (persp) {
435                            addSrcChoppedQuad(&q[i], !verbsInContour && 0 == i);
436                        } else {
437                            addChoppedQuad(nullptr, &q[i], !verbsInContour && 0 == i);
438                        }
439                    }
440                }
441                verbsInContour++;
442                break;
443            }
444            case SkPath::kClose_Verb:
445                // Contour is closed, so we don't need to grow the starting line, unless it's
446                // *just* a zero length subpath. (SVG Spec 11.4, 'stroke').
447                if (capLength > 0) {
448                    if (seenZeroLengthVerb && verbsInContour == 1) {
449                        SkPoint* pts = lines->push_back_n(2);
450                        pts[0] = SkPoint::Make(zeroVerbPt.fX - capLength, zeroVerbPt.fY);
451                        pts[1] = SkPoint::Make(zeroVerbPt.fX + capLength, zeroVerbPt.fY);
452                    } else if (verbsInContour == 0) {
453                        // Contour was (moveTo, close). Add a line.
454                        SkPoint devPts[2];
455                        m.mapPoints(devPts, pathPts, 1);
456                        devPts[1] = devPts[0];
457                        bounds.setBounds(devPts, 2);
458                        bounds.outset(SK_Scalar1, SK_Scalar1);
459                        bounds.roundOut(&ibounds);
460                        if (SkIRect::Intersects(devClipBounds, ibounds)) {
461                            SkPoint* pts = lines->push_back_n(2);
462                            pts[0] = SkPoint::Make(devPts[0].fX - capLength, devPts[0].fY);
463                            pts[1] = SkPoint::Make(devPts[1].fX + capLength, devPts[1].fY);
464                        }
465                    }
466                }
467                break;
468            case SkPath::kDone_Verb:
469                if (seenZeroLengthVerb && verbsInContour == 1 && capLength > 0) {
470                    // Path ended with a dangling (moveTo, line|quad|etc). If the final verb is
471                    // degenerate, we need to draw a line.
472                    SkPoint* pts = lines->push_back_n(2);
473                    pts[0] = SkPoint::Make(zeroVerbPt.fX - capLength, zeroVerbPt.fY);
474                    pts[1] = SkPoint::Make(zeroVerbPt.fX + capLength, zeroVerbPt.fY);
475                }
476                return totalQuadCount;
477        }
478    }
479}
480
481struct LineVertex {
482    SkPoint fPos;
483    float fCoverage;
484};
485
486struct BezierVertex {
487    SkPoint fPos;
488    union {
489        struct {
490            SkScalar fKLM[3];
491        } fConic;
492        SkVector   fQuadCoord;
493        struct {
494            SkScalar fBogus[4];
495        };
496    };
497};
498
499static_assert(sizeof(BezierVertex) == 3 * sizeof(SkPoint));
500
501void intersect_lines(const SkPoint& ptA, const SkVector& normA,
502                     const SkPoint& ptB, const SkVector& normB,
503                     SkPoint* result) {
504
505    SkScalar lineAW = -normA.dot(ptA);
506    SkScalar lineBW = -normB.dot(ptB);
507
508    SkScalar wInv = normA.fX * normB.fY - normA.fY * normB.fX;
509    wInv = SkScalarInvert(wInv);
510    if (!SkScalarIsFinite(wInv)) {
511        // lines are parallel, pick the point in between
512        *result = (ptA + ptB)*SK_ScalarHalf;
513        *result += normA;
514    } else {
515        result->fX = normA.fY * lineBW - lineAW * normB.fY;
516        result->fX *= wInv;
517
518        result->fY = lineAW * normB.fX - normA.fX * lineBW;
519        result->fY *= wInv;
520    }
521}
522
523void set_uv_quad(const SkPoint qpts[3], BezierVertex verts[kQuadNumVertices]) {
524    // this should be in the src space, not dev coords, when we have perspective
525    GrPathUtils::QuadUVMatrix DevToUV(qpts);
526    DevToUV.apply(verts, kQuadNumVertices, sizeof(BezierVertex), sizeof(SkPoint));
527}
528
529void bloat_quad(const SkPoint qpts[3],
530                const SkMatrix* toDevice,
531                const SkMatrix* toSrc,
532                BezierVertex verts[kQuadNumVertices]) {
533    SkASSERT(!toDevice == !toSrc);
534    // original quad is specified by tri a,b,c
535    SkPoint a = qpts[0];
536    SkPoint b = qpts[1];
537    SkPoint c = qpts[2];
538
539    if (toDevice) {
540        toDevice->mapPoints(&a, 1);
541        toDevice->mapPoints(&b, 1);
542        toDevice->mapPoints(&c, 1);
543    }
544    // make a new poly where we replace a and c by a 1-pixel wide edges orthog
545    // to edges ab and bc:
546    //
547    //   before       |        after
548    //                |              b0
549    //         b      |
550    //                |
551    //                |     a0            c0
552    // a         c    |        a1       c1
553    //
554    // edges a0->b0 and b0->c0 are parallel to original edges a->b and b->c,
555    // respectively.
556    BezierVertex& a0 = verts[0];
557    BezierVertex& a1 = verts[1];
558    BezierVertex& b0 = verts[2];
559    BezierVertex& c0 = verts[3];
560    BezierVertex& c1 = verts[4];
561
562    SkVector ab = b;
563    ab -= a;
564    SkVector ac = c;
565    ac -= a;
566    SkVector cb = b;
567    cb -= c;
568
569    // After the transform (or due to floating point math) we might have a line,
570    // try to do something reasonable
571    if (SkPointPriv::LengthSqd(ab) <= SK_ScalarNearlyZero*SK_ScalarNearlyZero) {
572        ab = cb;
573    }
574    if (SkPointPriv::LengthSqd(cb) <= SK_ScalarNearlyZero*SK_ScalarNearlyZero) {
575        cb = ab;
576    }
577
578    // We should have already handled degenerates
579    SkASSERT(ab.length() > 0 && cb.length() > 0);
580
581    ab.normalize();
582    SkVector abN = SkPointPriv::MakeOrthog(ab, SkPointPriv::kLeft_Side);
583    if (abN.dot(ac) > 0) {
584        abN.negate();
585    }
586
587    cb.normalize();
588    SkVector cbN = SkPointPriv::MakeOrthog(cb, SkPointPriv::kLeft_Side);
589    if (cbN.dot(ac) < 0) {
590        cbN.negate();
591    }
592
593    a0.fPos = a;
594    a0.fPos += abN;
595    a1.fPos = a;
596    a1.fPos -= abN;
597
598    if (toDevice && SkPointPriv::LengthSqd(ac) <= SK_ScalarNearlyZero*SK_ScalarNearlyZero) {
599        c = b;
600    }
601    c0.fPos = c;
602    c0.fPos += cbN;
603    c1.fPos = c;
604    c1.fPos -= cbN;
605
606    intersect_lines(a0.fPos, abN, c0.fPos, cbN, &b0.fPos);
607
608    if (toSrc) {
609        SkMatrixPriv::MapPointsWithStride(*toSrc, &verts[0].fPos, sizeof(BezierVertex),
610                                          kQuadNumVertices);
611    }
612}
613
614// Equations based off of Loop-Blinn Quadratic GPU Rendering
615// Input Parametric:
616// 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)
617// Output Implicit:
618// f(x, y, w) = f(P) = K^2 - LM
619// K = dot(k, P), L = dot(l, P), M = dot(m, P)
620// k, l, m are calculated in function GrPathUtils::getConicKLM
621void set_conic_coeffs(const SkPoint p[3],
622                      BezierVertex verts[kQuadNumVertices],
623                      const SkScalar weight) {
624    SkMatrix klm;
625
626    GrPathUtils::getConicKLM(p, weight, &klm);
627
628    for (int i = 0; i < kQuadNumVertices; ++i) {
629        const SkPoint3 pt3 = {verts[i].fPos.x(), verts[i].fPos.y(), 1.f};
630        klm.mapHomogeneousPoints((SkPoint3* ) verts[i].fConic.fKLM, &pt3, 1);
631    }
632}
633
634void add_conics(const SkPoint p[3],
635                const SkScalar weight,
636                const SkMatrix* toDevice,
637                const SkMatrix* toSrc,
638                BezierVertex** vert) {
639    bloat_quad(p, toDevice, toSrc, *vert);
640    set_conic_coeffs(p, *vert, weight);
641    *vert += kQuadNumVertices;
642}
643
644void add_quads(const SkPoint p[3],
645               int subdiv,
646               const SkMatrix* toDevice,
647               const SkMatrix* toSrc,
648               BezierVertex** vert) {
649    SkASSERT(subdiv >= 0);
650    // temporary vertex storage to avoid reading the vertex buffer
651    BezierVertex outVerts[kQuadNumVertices] = {};
652
653    // storage for the chopped quad
654    // pts 0,1,2 are the first quad, and 2,3,4 the second quad
655    SkPoint choppedQuadPts[5];
656    // start off with our original curve in the second quad slot
657    memcpy(&choppedQuadPts[2], p, 3*sizeof(SkPoint));
658
659    int stepCount = 1 << subdiv;
660    while (stepCount > 1) {
661        // The general idea is:
662        // * chop the quad using pts 2,3,4 as the input
663        // * write out verts using pts 0,1,2
664        // * now 2,3,4 is the remainder of the curve, chop again until all subdivisions are done
665        SkScalar h = 1.f / stepCount;
666        SkChopQuadAt(&choppedQuadPts[2], choppedQuadPts, h);
667
668        bloat_quad(choppedQuadPts, toDevice, toSrc, outVerts);
669        set_uv_quad(choppedQuadPts, outVerts);
670        memcpy(*vert, outVerts, kQuadNumVertices*sizeof(BezierVertex));
671        *vert += kQuadNumVertices;
672        --stepCount;
673    }
674
675    // finish up, write out the final quad
676    bloat_quad(&choppedQuadPts[2], toDevice, toSrc, outVerts);
677    set_uv_quad(&choppedQuadPts[2], outVerts);
678    memcpy(*vert, outVerts, kQuadNumVertices * sizeof(BezierVertex));
679    *vert += kQuadNumVertices;
680}
681
682void add_line(const SkPoint p[2],
683              const SkMatrix* toSrc,
684              uint8_t coverage,
685              LineVertex** vert) {
686    const SkPoint& a = p[0];
687    const SkPoint& b = p[1];
688
689    SkVector ortho, vec = b;
690    vec -= a;
691
692    SkScalar lengthSqd = SkPointPriv::LengthSqd(vec);
693
694    if (vec.setLength(SK_ScalarHalf)) {
695        // Create a vector orthogonal to 'vec' and of unit length
696        ortho.fX = 2.0f * vec.fY;
697        ortho.fY = -2.0f * vec.fX;
698
699        float floatCoverage = GrNormalizeByteToFloat(coverage);
700
701        if (lengthSqd >= 1.0f) {
702            // Relative to points a and b:
703            // The inner vertices are inset half a pixel along the line a,b
704            (*vert)[0].fPos = a + vec;
705            (*vert)[0].fCoverage = floatCoverage;
706            (*vert)[1].fPos = b - vec;
707            (*vert)[1].fCoverage = floatCoverage;
708        } else {
709            // The inner vertices are inset a distance of length(a,b) from the outer edge of
710            // geometry. For the "a" inset this is the same as insetting from b by half a pixel.
711            // The coverage is then modulated by the length. This gives us the correct
712            // coverage for rects shorter than a pixel as they get translated subpixel amounts
713            // inside of a pixel.
714            SkScalar length = SkScalarSqrt(lengthSqd);
715            (*vert)[0].fPos = b - vec;
716            (*vert)[0].fCoverage = floatCoverage * length;
717            (*vert)[1].fPos = a + vec;
718            (*vert)[1].fCoverage = floatCoverage * length;
719        }
720        // Relative to points a and b:
721        // The outer vertices are outset half a pixel along the line a,b and then a whole pixel
722        // orthogonally.
723        (*vert)[2].fPos = a - vec + ortho;
724        (*vert)[2].fCoverage = 0;
725        (*vert)[3].fPos = b + vec + ortho;
726        (*vert)[3].fCoverage = 0;
727        (*vert)[4].fPos = a - vec - ortho;
728        (*vert)[4].fCoverage = 0;
729        (*vert)[5].fPos = b + vec - ortho;
730        (*vert)[5].fCoverage = 0;
731
732        if (toSrc) {
733            SkMatrixPriv::MapPointsWithStride(*toSrc, &(*vert)->fPos, sizeof(LineVertex),
734                                              kLineSegNumVertices);
735        }
736    } else {
737        // just make it degenerate and likely offscreen
738        for (int i = 0; i < kLineSegNumVertices; ++i) {
739            (*vert)[i].fPos.set(SK_ScalarMax, SK_ScalarMax);
740        }
741    }
742
743    *vert += kLineSegNumVertices;
744}
745
746///////////////////////////////////////////////////////////////////////////////
747
748class AAHairlineOp final : public GrMeshDrawOp {
749private:
750    using Helper = GrSimpleMeshDrawOpHelperWithStencil;
751
752public:
753    DEFINE_OP_CLASS_ID
754
755    static GrOp::Owner Make(GrRecordingContext* context,
756                            GrPaint&& paint,
757                            const SkMatrix& viewMatrix,
758                            const SkPath& path,
759                            const GrStyle& style,
760                            const SkIRect& devClipBounds,
761                            const GrUserStencilSettings* stencilSettings) {
762        SkScalar hairlineCoverage;
763        uint8_t newCoverage = 0xff;
764        if (GrIsStrokeHairlineOrEquivalent(style, viewMatrix, &hairlineCoverage)) {
765            newCoverage = SkScalarRoundToInt(hairlineCoverage * 0xff);
766        }
767
768        const SkStrokeRec& stroke = style.strokeRec();
769        SkScalar capLength = SkPaint::kButt_Cap != stroke.getCap() ? hairlineCoverage * 0.5f : 0.0f;
770
771        return Helper::FactoryHelper<AAHairlineOp>(context, std::move(paint), newCoverage,
772                                                   viewMatrix, path,
773                                                   devClipBounds, capLength, stencilSettings);
774    }
775
776    AAHairlineOp(GrProcessorSet* processorSet,
777                 const SkPMColor4f& color,
778                 uint8_t coverage,
779                 const SkMatrix& viewMatrix,
780                 const SkPath& path,
781                 SkIRect devClipBounds,
782                 SkScalar capLength,
783                 const GrUserStencilSettings* stencilSettings)
784            : INHERITED(ClassID())
785            , fHelper(processorSet, GrAAType::kCoverage, stencilSettings)
786            , fColor(color)
787            , fCoverage(coverage) {
788        fPaths.emplace_back(PathData{viewMatrix, path, devClipBounds, capLength});
789
790        this->setTransformedBounds(path.getBounds(), viewMatrix, HasAABloat::kYes,
791                                   IsHairline::kYes);
792    }
793
794    const char* name() const override { return "AAHairlineOp"; }
795
796    void visitProxies(const GrVisitProxyFunc& func) const override {
797
798        bool visited = false;
799        for (int i = 0; i < 3; ++i) {
800            if (fProgramInfos[i]) {
801                fProgramInfos[i]->visitFPProxies(func);
802                visited = true;
803            }
804        }
805
806        if (!visited) {
807            fHelper.visitProxies(func);
808        }
809    }
810
811    FixedFunctionFlags fixedFunctionFlags() const override { return fHelper.fixedFunctionFlags(); }
812
813    GrProcessorSet::Analysis finalize(const GrCaps& caps, const GrAppliedClip* clip,
814                                      GrClampType clampType) override {
815        // This Op uses uniform (not vertex) color, so doesn't need to track wide color.
816        return fHelper.finalizeProcessors(caps, clip, clampType,
817                                          GrProcessorAnalysisCoverage::kSingleChannel, &fColor,
818                                          nullptr);
819    }
820
821    enum class Program : uint8_t {
822        kNone  = 0x0,
823        kLine  = 0x1,
824        kQuad  = 0x2,
825        kConic = 0x4,
826    };
827
828private:
829    void makeLineProgramInfo(const GrCaps&, SkArenaAlloc*, const GrPipeline*,
830                             const GrSurfaceProxyView& writeView,
831                             bool usesMSAASurface,
832                             const SkMatrix* geometryProcessorViewM,
833                             const SkMatrix* geometryProcessorLocalM,
834                             GrXferBarrierFlags renderPassXferBarriers,
835                             GrLoadOp colorLoadOp);
836    void makeQuadProgramInfo(const GrCaps&, SkArenaAlloc*, const GrPipeline*,
837                             const GrSurfaceProxyView& writeView,
838                             bool usesMSAASurface,
839                             const SkMatrix* geometryProcessorViewM,
840                             const SkMatrix* geometryProcessorLocalM,
841                             GrXferBarrierFlags renderPassXferBarriers,
842                             GrLoadOp colorLoadOp);
843    void makeConicProgramInfo(const GrCaps&, SkArenaAlloc*, const GrPipeline*,
844                              const GrSurfaceProxyView& writeView,
845                              bool usesMSAASurface,
846                              const SkMatrix* geometryProcessorViewM,
847                              const SkMatrix* geometryProcessorLocalM,
848                              GrXferBarrierFlags renderPassXferBarriers,
849                              GrLoadOp colorLoadOp);
850
851    GrProgramInfo* programInfo() override {
852        // This Op has 3 programInfos and implements its own onPrePrepareDraws so this entry point
853        // should really never be called.
854        SkASSERT(0);
855        return nullptr;
856    }
857
858    Program predictPrograms(const GrCaps*) const;
859
860    void onCreateProgramInfo(const GrCaps*,
861                             SkArenaAlloc*,
862                             const GrSurfaceProxyView& writeView,
863                             bool usesMSAASurface,
864                             GrAppliedClip&&,
865                             const GrDstProxyView&,
866                             GrXferBarrierFlags renderPassXferBarriers,
867                             GrLoadOp colorLoadOp) override;
868
869    void onPrePrepareDraws(GrRecordingContext*,
870                           const GrSurfaceProxyView& writeView,
871                           GrAppliedClip*,
872                           const GrDstProxyView&,
873                           GrXferBarrierFlags renderPassXferBarriers,
874                           GrLoadOp colorLoadOp) override;
875
876    void onPrepareDraws(GrMeshDrawTarget*) override;
877    void onExecute(GrOpFlushState*, const SkRect& chainBounds) override;
878
879    CombineResult onCombineIfPossible(GrOp* t, SkArenaAlloc*, const GrCaps& caps) override {
880        AAHairlineOp* that = t->cast<AAHairlineOp>();
881
882        if (!fHelper.isCompatible(that->fHelper, caps, this->bounds(), that->bounds())) {
883            return CombineResult::kCannotCombine;
884        }
885
886        if (this->viewMatrix().hasPerspective() != that->viewMatrix().hasPerspective()) {
887            return CombineResult::kCannotCombine;
888        }
889
890        // We go to identity if we don't have perspective
891        if (this->viewMatrix().hasPerspective() &&
892            !SkMatrixPriv::CheapEqual(this->viewMatrix(), that->viewMatrix())) {
893            return CombineResult::kCannotCombine;
894        }
895
896        // TODO we can actually combine hairlines if they are the same color in a kind of bulk
897        // method but we haven't implemented this yet
898        // TODO investigate going to vertex color and coverage?
899        if (this->coverage() != that->coverage()) {
900            return CombineResult::kCannotCombine;
901        }
902
903        if (this->color() != that->color()) {
904            return CombineResult::kCannotCombine;
905        }
906
907        if (fHelper.usesLocalCoords() && !SkMatrixPriv::CheapEqual(this->viewMatrix(),
908                                                                   that->viewMatrix())) {
909            return CombineResult::kCannotCombine;
910        }
911
912        fPaths.push_back_n(that->fPaths.count(), that->fPaths.begin());
913        return CombineResult::kMerged;
914    }
915
916#if GR_TEST_UTILS
917    SkString onDumpInfo() const override {
918        return SkStringPrintf("Color: 0x%08x Coverage: 0x%02x, Count: %d\n%s",
919                              fColor.toBytes_RGBA(), fCoverage, fPaths.count(),
920                              fHelper.dumpInfo().c_str());
921    }
922#endif
923
924    const SkPMColor4f& color() const { return fColor; }
925    uint8_t coverage() const { return fCoverage; }
926    const SkMatrix& viewMatrix() const { return fPaths[0].fViewMatrix; }
927
928    struct PathData {
929        SkMatrix fViewMatrix;
930        SkPath fPath;
931        SkIRect fDevClipBounds;
932        SkScalar fCapLength;
933    };
934
935    SkSTArray<1, PathData, true> fPaths;
936    Helper fHelper;
937    SkPMColor4f fColor;
938    uint8_t fCoverage;
939
940    Program        fCharacterization = Program::kNone;       // holds a mask of required programs
941    GrSimpleMesh*  fMeshes[3] = { nullptr };
942    GrProgramInfo* fProgramInfos[3] = { nullptr };
943
944    using INHERITED = GrMeshDrawOp;
945};
946
947GR_MAKE_BITFIELD_CLASS_OPS(AAHairlineOp::Program)
948
949void AAHairlineOp::makeLineProgramInfo(const GrCaps& caps, SkArenaAlloc* arena,
950                                       const GrPipeline* pipeline,
951                                       const GrSurfaceProxyView& writeView,
952                                       bool usesMSAASurface,
953                                       const SkMatrix* geometryProcessorViewM,
954                                       const SkMatrix* geometryProcessorLocalM,
955                                       GrXferBarrierFlags renderPassXferBarriers,
956                                       GrLoadOp colorLoadOp) {
957    if (fProgramInfos[0]) {
958        return;
959    }
960
961    GrGeometryProcessor* lineGP;
962    {
963        using namespace GrDefaultGeoProcFactory;
964
965        Color color(this->color());
966        LocalCoords localCoords(fHelper.usesLocalCoords() ? LocalCoords::kUsePosition_Type
967                                                          : LocalCoords::kUnused_Type);
968        localCoords.fMatrix = geometryProcessorLocalM;
969
970        lineGP = GrDefaultGeoProcFactory::Make(arena,
971                                               color,
972                                               Coverage::kAttribute_Type,
973                                               localCoords,
974                                               *geometryProcessorViewM);
975        SkASSERT(sizeof(LineVertex) == lineGP->vertexStride());
976    }
977
978    fProgramInfos[0] = GrSimpleMeshDrawOpHelper::CreateProgramInfo(
979            &caps, arena, pipeline, writeView, usesMSAASurface, lineGP, GrPrimitiveType::kTriangles,
980            renderPassXferBarriers, colorLoadOp, fHelper.stencilSettings());
981}
982
983void AAHairlineOp::makeQuadProgramInfo(const GrCaps& caps, SkArenaAlloc* arena,
984                                       const GrPipeline* pipeline,
985                                       const GrSurfaceProxyView& writeView,
986                                       bool usesMSAASurface,
987                                       const SkMatrix* geometryProcessorViewM,
988                                       const SkMatrix* geometryProcessorLocalM,
989                                       GrXferBarrierFlags renderPassXferBarriers,
990                                       GrLoadOp colorLoadOp) {
991    if (fProgramInfos[1]) {
992        return;
993    }
994
995    GrGeometryProcessor* quadGP = GrQuadEffect::Make(arena,
996                                                     this->color(),
997                                                     *geometryProcessorViewM,
998                                                     caps,
999                                                     *geometryProcessorLocalM,
1000                                                     fHelper.usesLocalCoords(),
1001                                                     this->coverage());
1002    SkASSERT(sizeof(BezierVertex) == quadGP->vertexStride());
1003
1004    fProgramInfos[1] = GrSimpleMeshDrawOpHelper::CreateProgramInfo(
1005            &caps, arena, pipeline, writeView, usesMSAASurface, quadGP, GrPrimitiveType::kTriangles,
1006            renderPassXferBarriers, colorLoadOp, fHelper.stencilSettings());
1007}
1008
1009void AAHairlineOp::makeConicProgramInfo(const GrCaps& caps, SkArenaAlloc* arena,
1010                                        const GrPipeline* pipeline,
1011                                        const GrSurfaceProxyView& writeView,
1012                                        bool usesMSAASurface,
1013                                        const SkMatrix* geometryProcessorViewM,
1014                                        const SkMatrix* geometryProcessorLocalM,
1015                                        GrXferBarrierFlags renderPassXferBarriers,
1016                                        GrLoadOp colorLoadOp) {
1017    if (fProgramInfos[2]) {
1018        return;
1019    }
1020
1021    GrGeometryProcessor* conicGP = GrConicEffect::Make(arena,
1022                                                       this->color(),
1023                                                       *geometryProcessorViewM,
1024                                                       caps,
1025                                                       *geometryProcessorLocalM,
1026                                                       fHelper.usesLocalCoords(),
1027                                                       this->coverage());
1028    SkASSERT(sizeof(BezierVertex) == conicGP->vertexStride());
1029
1030    fProgramInfos[2] = GrSimpleMeshDrawOpHelper::CreateProgramInfo(
1031            &caps, arena, pipeline, writeView, usesMSAASurface, conicGP,
1032            GrPrimitiveType::kTriangles, renderPassXferBarriers, colorLoadOp,
1033            fHelper.stencilSettings());
1034}
1035
1036AAHairlineOp::Program AAHairlineOp::predictPrograms(const GrCaps* caps) const {
1037    bool convertConicsToQuads = !caps->shaderCaps()->floatIs32Bits();
1038
1039    // When predicting the programs we always include the lineProgram bc it is used as a fallback
1040    // for quads and conics. In non-DDL mode there are cases where it sometimes isn't needed for a
1041    // given path.
1042    Program neededPrograms = Program::kLine;
1043
1044    for (int i = 0; i < fPaths.count(); i++) {
1045        uint32_t mask = fPaths[i].fPath.getSegmentMasks();
1046
1047        if (mask & (SkPath::kQuad_SegmentMask | SkPath::kCubic_SegmentMask)) {
1048            neededPrograms |= Program::kQuad;
1049        }
1050        if (mask & SkPath::kConic_SegmentMask) {
1051            if (convertConicsToQuads) {
1052                neededPrograms |= Program::kQuad;
1053            } else {
1054                neededPrograms |= Program::kConic;
1055            }
1056        }
1057    }
1058
1059    return neededPrograms;
1060}
1061
1062void AAHairlineOp::onCreateProgramInfo(const GrCaps* caps,
1063                                       SkArenaAlloc* arena,
1064                                       const GrSurfaceProxyView& writeView,
1065                                       bool usesMSAASurface,
1066                                       GrAppliedClip&& appliedClip,
1067                                       const GrDstProxyView& dstProxyView,
1068                                       GrXferBarrierFlags renderPassXferBarriers,
1069                                       GrLoadOp colorLoadOp) {
1070    // Setup the viewmatrix and localmatrix for the GrGeometryProcessor.
1071    SkMatrix invert;
1072    if (!this->viewMatrix().invert(&invert)) {
1073        return;
1074    }
1075
1076    // we will transform to identity space if the viewmatrix does not have perspective
1077    bool hasPerspective = this->viewMatrix().hasPerspective();
1078    const SkMatrix* geometryProcessorViewM = &SkMatrix::I();
1079    const SkMatrix* geometryProcessorLocalM = &invert;
1080    if (hasPerspective) {
1081        geometryProcessorViewM = &this->viewMatrix();
1082        geometryProcessorLocalM = &SkMatrix::I();
1083    }
1084
1085    auto pipeline = fHelper.createPipeline(caps, arena, writeView.swizzle(),
1086                                           std::move(appliedClip), dstProxyView);
1087
1088    if (fCharacterization & Program::kLine) {
1089        this->makeLineProgramInfo(*caps, arena, pipeline, writeView, usesMSAASurface,
1090                                  geometryProcessorViewM, geometryProcessorLocalM,
1091                                  renderPassXferBarriers, colorLoadOp);
1092    }
1093    if (fCharacterization & Program::kQuad) {
1094        this->makeQuadProgramInfo(*caps, arena, pipeline, writeView, usesMSAASurface,
1095                                  geometryProcessorViewM, geometryProcessorLocalM,
1096                                  renderPassXferBarriers, colorLoadOp);
1097    }
1098    if (fCharacterization & Program::kConic) {
1099        this->makeConicProgramInfo(*caps, arena, pipeline, writeView, usesMSAASurface,
1100                                   geometryProcessorViewM, geometryProcessorLocalM,
1101                                   renderPassXferBarriers, colorLoadOp);
1102
1103    }
1104}
1105
1106void AAHairlineOp::onPrePrepareDraws(GrRecordingContext* context,
1107                                     const GrSurfaceProxyView& writeView,
1108                                     GrAppliedClip* clip,
1109                                     const GrDstProxyView& dstProxyView,
1110                                     GrXferBarrierFlags renderPassXferBarriers,
1111                                     GrLoadOp colorLoadOp) {
1112    SkArenaAlloc* arena = context->priv().recordTimeAllocator();
1113    const GrCaps* caps = context->priv().caps();
1114
1115    // http://skbug.com/12201 -- DDL does not yet support DMSAA.
1116    bool usesMSAASurface = writeView.asRenderTargetProxy()->numSamples() > 1;
1117
1118    // This is equivalent to a GrOpFlushState::detachAppliedClip
1119    GrAppliedClip appliedClip = clip ? std::move(*clip) : GrAppliedClip::Disabled();
1120
1121    // Conservatively predict which programs will be required
1122    fCharacterization = this->predictPrograms(caps);
1123
1124    this->createProgramInfo(caps, arena, writeView, usesMSAASurface, std::move(appliedClip),
1125                            dstProxyView, renderPassXferBarriers, colorLoadOp);
1126
1127    context->priv().recordProgramInfo(fProgramInfos[0]);
1128    context->priv().recordProgramInfo(fProgramInfos[1]);
1129    context->priv().recordProgramInfo(fProgramInfos[2]);
1130}
1131
1132void AAHairlineOp::onPrepareDraws(GrMeshDrawTarget* target) {
1133    // Setup the viewmatrix and localmatrix for the GrGeometryProcessor.
1134    SkMatrix invert;
1135    if (!this->viewMatrix().invert(&invert)) {
1136        return;
1137    }
1138
1139    // we will transform to identity space if the viewmatrix does not have perspective
1140    const SkMatrix* toDevice = nullptr;
1141    const SkMatrix* toSrc = nullptr;
1142    if (this->viewMatrix().hasPerspective()) {
1143        toDevice = &this->viewMatrix();
1144        toSrc = &invert;
1145    }
1146
1147    SkDEBUGCODE(Program predictedPrograms = this->predictPrograms(&target->caps()));
1148    Program actualPrograms = Program::kNone;
1149
1150    // This is hand inlined for maximum performance.
1151    PREALLOC_PTARRAY(128) lines;
1152    PREALLOC_PTARRAY(128) quads;
1153    PREALLOC_PTARRAY(128) conics;
1154    IntArray qSubdivs;
1155    FloatArray cWeights;
1156    int quadCount = 0;
1157
1158    int instanceCount = fPaths.count();
1159    bool convertConicsToQuads = !target->caps().shaderCaps()->floatIs32Bits();
1160    for (int i = 0; i < instanceCount; i++) {
1161        const PathData& args = fPaths[i];
1162        quadCount += gather_lines_and_quads(args.fPath, args.fViewMatrix, args.fDevClipBounds,
1163                                            args.fCapLength, convertConicsToQuads, &lines, &quads,
1164                                            &conics, &qSubdivs, &cWeights);
1165    }
1166
1167    int lineCount = lines.count() / 2;
1168    int conicCount = conics.count() / 3;
1169    int quadAndConicCount = conicCount + quadCount;
1170
1171    static constexpr int kMaxLines = SK_MaxS32 / kLineSegNumVertices;
1172    static constexpr int kMaxQuadsAndConics = SK_MaxS32 / kQuadNumVertices;
1173    if (lineCount > kMaxLines || quadAndConicCount > kMaxQuadsAndConics) {
1174        return;
1175    }
1176
1177    // do lines first
1178    if (lineCount) {
1179        SkASSERT(predictedPrograms & Program::kLine);
1180        actualPrograms |= Program::kLine;
1181
1182        sk_sp<const GrBuffer> linesIndexBuffer = get_lines_index_buffer(target->resourceProvider());
1183
1184        GrMeshDrawOp::PatternHelper helper(target, GrPrimitiveType::kTriangles, sizeof(LineVertex),
1185                                           std::move(linesIndexBuffer), kLineSegNumVertices,
1186                                           kIdxsPerLineSeg, lineCount, kLineSegsNumInIdxBuffer);
1187
1188        LineVertex* verts = reinterpret_cast<LineVertex*>(helper.vertices());
1189        if (!verts) {
1190            SkDebugf("Could not allocate vertices\n");
1191            return;
1192        }
1193
1194        for (int i = 0; i < lineCount; ++i) {
1195            add_line(&lines[2*i], toSrc, this->coverage(), &verts);
1196        }
1197
1198        fMeshes[0] = helper.mesh();
1199    }
1200
1201    if (quadCount || conicCount) {
1202        sk_sp<const GrBuffer> vertexBuffer;
1203        int firstVertex;
1204
1205        sk_sp<const GrBuffer> quadsIndexBuffer = get_quads_index_buffer(target->resourceProvider());
1206
1207        int vertexCount = kQuadNumVertices * quadAndConicCount;
1208        void* vertices = target->makeVertexSpace(sizeof(BezierVertex), vertexCount, &vertexBuffer,
1209                                                 &firstVertex);
1210
1211        if (!vertices || !quadsIndexBuffer) {
1212            SkDebugf("Could not allocate vertices\n");
1213            return;
1214        }
1215
1216        // Setup vertices
1217        BezierVertex* bezVerts = reinterpret_cast<BezierVertex*>(vertices);
1218
1219        int unsubdivQuadCnt = quads.count() / 3;
1220        for (int i = 0; i < unsubdivQuadCnt; ++i) {
1221            SkASSERT(qSubdivs[i] >= 0);
1222            if (!quads[3*i].isFinite() || !quads[3*i+1].isFinite() || !quads[3*i+2].isFinite()) {
1223                return;
1224            }
1225            add_quads(&quads[3*i], qSubdivs[i], toDevice, toSrc, &bezVerts);
1226        }
1227
1228        // Start Conics
1229        for (int i = 0; i < conicCount; ++i) {
1230            add_conics(&conics[3*i], cWeights[i], toDevice, toSrc, &bezVerts);
1231        }
1232
1233        if (quadCount > 0) {
1234            SkASSERT(predictedPrograms & Program::kQuad);
1235            actualPrograms |= Program::kQuad;
1236
1237            fMeshes[1] = target->allocMesh();
1238            fMeshes[1]->setIndexedPatterned(quadsIndexBuffer, kIdxsPerQuad, quadCount,
1239                                            kQuadsNumInIdxBuffer, vertexBuffer, kQuadNumVertices,
1240                                            firstVertex);
1241            firstVertex += quadCount * kQuadNumVertices;
1242        }
1243
1244        if (conicCount > 0) {
1245            SkASSERT(predictedPrograms & Program::kConic);
1246            actualPrograms |= Program::kConic;
1247
1248            fMeshes[2] = target->allocMesh();
1249            fMeshes[2]->setIndexedPatterned(std::move(quadsIndexBuffer), kIdxsPerQuad, conicCount,
1250                                            kQuadsNumInIdxBuffer, std::move(vertexBuffer),
1251                                            kQuadNumVertices, firstVertex);
1252        }
1253    }
1254
1255    // In DDL mode this will replace the predicted program requirements with the actual ones.
1256    // However, we will already have surfaced the predicted programs to the DDL.
1257    fCharacterization = actualPrograms;
1258}
1259
1260void AAHairlineOp::onExecute(GrOpFlushState* flushState, const SkRect& chainBounds) {
1261    this->createProgramInfo(flushState);
1262
1263    for (int i = 0; i < 3; ++i) {
1264        if (fProgramInfos[i] && fMeshes[i]) {
1265            flushState->bindPipelineAndScissorClip(*fProgramInfos[i], chainBounds);
1266            flushState->bindTextures(fProgramInfos[i]->geomProc(), nullptr,
1267                                     fProgramInfos[i]->pipeline());
1268            flushState->drawMesh(*fMeshes[i]);
1269        }
1270    }
1271}
1272
1273} // anonymous namespace
1274
1275///////////////////////////////////////////////////////////////////////////////////////////////////
1276
1277#if GR_TEST_UTILS
1278
1279GR_DRAW_OP_TEST_DEFINE(AAHairlineOp) {
1280    SkMatrix viewMatrix = GrTest::TestMatrix(random);
1281    const SkPath& path = GrTest::TestPath(random);
1282    SkIRect devClipBounds;
1283    devClipBounds.setEmpty();
1284    return AAHairlineOp::Make(context, std::move(paint), viewMatrix, path,
1285                              GrStyle::SimpleHairline(), devClipBounds,
1286                              GrGetRandomStencil(random, context));
1287}
1288
1289#endif
1290
1291///////////////////////////////////////////////////////////////////////////////////////////////////
1292
1293namespace skgpu::v1 {
1294
1295PathRenderer::CanDrawPath AAHairLinePathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
1296    if (GrAAType::kCoverage != args.fAAType) {
1297        return CanDrawPath::kNo;
1298    }
1299
1300    if (!GrIsStrokeHairlineOrEquivalent(args.fShape->style(), *args.fViewMatrix, nullptr)) {
1301        return CanDrawPath::kNo;
1302    }
1303
1304    // We don't currently handle dashing in this class though perhaps we should.
1305    if (args.fShape->style().pathEffect()) {
1306        return CanDrawPath::kNo;
1307    }
1308
1309    if (SkPath::kLine_SegmentMask == args.fShape->segmentMask() ||
1310        args.fCaps->shaderCaps()->shaderDerivativeSupport()) {
1311        return CanDrawPath::kYes;
1312    }
1313
1314    return CanDrawPath::kNo;
1315}
1316
1317
1318bool AAHairLinePathRenderer::onDrawPath(const DrawPathArgs& args) {
1319    GR_AUDIT_TRAIL_AUTO_FRAME(args.fContext->priv().auditTrail(),
1320                              "AAHairlinePathRenderer::onDrawPath");
1321    SkASSERT(args.fSurfaceDrawContext->numSamples() <= 1);
1322
1323    SkPath path;
1324    args.fShape->asPath(&path);
1325    GrOp::Owner op =
1326            AAHairlineOp::Make(args.fContext, std::move(args.fPaint), *args.fViewMatrix, path,
1327                               args.fShape->style(), *args.fClipConservativeBounds,
1328                               args.fUserStencilSettings);
1329    args.fSurfaceDrawContext->addDrawOp(args.fClip, std::move(op));
1330    return true;
1331}
1332
1333} // namespace skgpu::v1
1334
1335