| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "GrAAHairLinePathRenderer.h" |
| #include "GrBuffer.h" |
| #include "GrCaps.h" |
| #include "GrClip.h" |
| #include "GrContext.h" |
| #include "GrDefaultGeoProcFactory.h" |
| #include "GrDrawOpTest.h" |
| #include "GrOpFlushState.h" |
| #include "GrPathUtils.h" |
| #include "GrProcessor.h" |
| #include "GrResourceProvider.h" |
| #include "GrSimpleMeshDrawOpHelper.h" |
| #include "SkGeometry.h" |
| #include "SkStroke.h" |
| #include "SkTemplates.h" |
| #include "effects/GrBezierEffect.h" |
| #include "ops/GrMeshDrawOp.h" |
| |
| #define PREALLOC_PTARRAY(N) SkSTArray<(N),SkPoint, true> |
| |
| // quadratics are rendered as 5-sided polys in order to bound the |
| // AA stroke around the center-curve. See comments in push_quad_index_buffer and |
| // bloat_quad. Quadratics and conics share an index buffer |
| |
| // lines are rendered as: |
| // *______________* |
| // |\ -_______ /| |
| // | \ \ / | |
| // | *--------* | |
| // | / ______/ \ | |
| // */_-__________\* |
| // For: 6 vertices and 18 indices (for 6 triangles) |
| |
| // Each quadratic is rendered as a five sided polygon. This poly bounds |
| // the quadratic's bounding triangle but has been expanded so that the |
| // 1-pixel wide area around the curve is inside the poly. |
| // If a,b,c are the original control points then the poly a0,b0,c0,c1,a1 |
| // that is rendered would look like this: |
| // b0 |
| // b |
| // |
| // a0 c0 |
| // a c |
| // a1 c1 |
| // Each is drawn as three triangles ((a0,a1,b0), (b0,c1,c0), (a1,c1,b0)) |
| // specified by these 9 indices: |
| static const uint16_t kQuadIdxBufPattern[] = { |
| 0, 1, 2, |
| 2, 4, 3, |
| 1, 4, 2 |
| }; |
| |
| static const int kIdxsPerQuad = SK_ARRAY_COUNT(kQuadIdxBufPattern); |
| static const int kQuadNumVertices = 5; |
| static const int kQuadsNumInIdxBuffer = 256; |
| GR_DECLARE_STATIC_UNIQUE_KEY(gQuadsIndexBufferKey); |
| |
| static const GrBuffer* ref_quads_index_buffer(GrResourceProvider* resourceProvider) { |
| GR_DEFINE_STATIC_UNIQUE_KEY(gQuadsIndexBufferKey); |
| return resourceProvider->findOrCreatePatternedIndexBuffer( |
| kQuadIdxBufPattern, kIdxsPerQuad, kQuadsNumInIdxBuffer, kQuadNumVertices, |
| gQuadsIndexBufferKey); |
| } |
| |
| |
| // Each line segment is rendered as two quads and two triangles. |
| // p0 and p1 have alpha = 1 while all other points have alpha = 0. |
| // The four external points are offset 1 pixel perpendicular to the |
| // line and half a pixel parallel to the line. |
| // |
| // p4 p5 |
| // p0 p1 |
| // p2 p3 |
| // |
| // Each is drawn as six triangles specified by these 18 indices: |
| |
| static const uint16_t kLineSegIdxBufPattern[] = { |
| 0, 1, 3, |
| 0, 3, 2, |
| 0, 4, 5, |
| 0, 5, 1, |
| 0, 2, 4, |
| 1, 5, 3 |
| }; |
| |
| static const int kIdxsPerLineSeg = SK_ARRAY_COUNT(kLineSegIdxBufPattern); |
| static const int kLineSegNumVertices = 6; |
| static const int kLineSegsNumInIdxBuffer = 256; |
| |
| GR_DECLARE_STATIC_UNIQUE_KEY(gLinesIndexBufferKey); |
| |
| static const GrBuffer* ref_lines_index_buffer(GrResourceProvider* resourceProvider) { |
| GR_DEFINE_STATIC_UNIQUE_KEY(gLinesIndexBufferKey); |
| return resourceProvider->findOrCreatePatternedIndexBuffer( |
| kLineSegIdxBufPattern, kIdxsPerLineSeg, kLineSegsNumInIdxBuffer, kLineSegNumVertices, |
| gLinesIndexBufferKey); |
| } |
| |
| // Takes 178th time of logf on Z600 / VC2010 |
| static int get_float_exp(float x) { |
| GR_STATIC_ASSERT(sizeof(int) == sizeof(float)); |
| #ifdef SK_DEBUG |
| static bool tested; |
| if (!tested) { |
| tested = true; |
| SkASSERT(get_float_exp(0.25f) == -2); |
| SkASSERT(get_float_exp(0.3f) == -2); |
| SkASSERT(get_float_exp(0.5f) == -1); |
| SkASSERT(get_float_exp(1.f) == 0); |
| SkASSERT(get_float_exp(2.f) == 1); |
| SkASSERT(get_float_exp(2.5f) == 1); |
| SkASSERT(get_float_exp(8.f) == 3); |
| SkASSERT(get_float_exp(100.f) == 6); |
| SkASSERT(get_float_exp(1000.f) == 9); |
| SkASSERT(get_float_exp(1024.f) == 10); |
| SkASSERT(get_float_exp(3000000.f) == 21); |
| } |
| #endif |
| const int* iptr = (const int*)&x; |
| return (((*iptr) & 0x7f800000) >> 23) - 127; |
| } |
| |
| // Uses the max curvature function for quads to estimate |
| // where to chop the conic. If the max curvature is not |
| // found along the curve segment it will return 1 and |
| // dst[0] is the original conic. If it returns 2 the dst[0] |
| // and dst[1] are the two new conics. |
| static int split_conic(const SkPoint src[3], SkConic dst[2], const SkScalar weight) { |
| SkScalar t = SkFindQuadMaxCurvature(src); |
| if (t == 0) { |
| if (dst) { |
| dst[0].set(src, weight); |
| } |
| return 1; |
| } else { |
| if (dst) { |
| SkConic conic; |
| conic.set(src, weight); |
| if (!conic.chopAt(t, dst)) { |
| dst[0].set(src, weight); |
| return 1; |
| } |
| } |
| return 2; |
| } |
| } |
| |
| // Calls split_conic on the entire conic and then once more on each subsection. |
| // Most cases will result in either 1 conic (chop point is not within t range) |
| // or 3 points (split once and then one subsection is split again). |
| static int chop_conic(const SkPoint src[3], SkConic dst[4], const SkScalar weight) { |
| SkConic dstTemp[2]; |
| int conicCnt = split_conic(src, dstTemp, weight); |
| if (2 == conicCnt) { |
| int conicCnt2 = split_conic(dstTemp[0].fPts, dst, dstTemp[0].fW); |
| conicCnt = conicCnt2 + split_conic(dstTemp[1].fPts, &dst[conicCnt2], dstTemp[1].fW); |
| } else { |
| dst[0] = dstTemp[0]; |
| } |
| return conicCnt; |
| } |
| |
| // returns 0 if quad/conic is degen or close to it |
| // in this case approx the path with lines |
| // otherwise returns 1 |
| static int is_degen_quad_or_conic(const SkPoint p[3], SkScalar* dsqd) { |
| static const SkScalar gDegenerateToLineTol = GrPathUtils::kDefaultTolerance; |
| static const SkScalar gDegenerateToLineTolSqd = |
| gDegenerateToLineTol * gDegenerateToLineTol; |
| |
| if (p[0].distanceToSqd(p[1]) < gDegenerateToLineTolSqd || |
| p[1].distanceToSqd(p[2]) < gDegenerateToLineTolSqd) { |
| return 1; |
| } |
| |
| *dsqd = p[1].distanceToLineBetweenSqd(p[0], p[2]); |
| if (*dsqd < gDegenerateToLineTolSqd) { |
| return 1; |
| } |
| |
| if (p[2].distanceToLineBetweenSqd(p[1], p[0]) < gDegenerateToLineTolSqd) { |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int is_degen_quad_or_conic(const SkPoint p[3]) { |
| SkScalar dsqd; |
| return is_degen_quad_or_conic(p, &dsqd); |
| } |
| |
| // we subdivide the quads to avoid huge overfill |
| // if it returns -1 then should be drawn as lines |
| static int num_quad_subdivs(const SkPoint p[3]) { |
| SkScalar dsqd; |
| if (is_degen_quad_or_conic(p, &dsqd)) { |
| return -1; |
| } |
| |
| // tolerance of triangle height in pixels |
| // tuned on windows Quadro FX 380 / Z600 |
| // trade off of fill vs cpu time on verts |
| // maybe different when do this using gpu (geo or tess shaders) |
| static const SkScalar gSubdivTol = 175 * SK_Scalar1; |
| |
| if (dsqd <= gSubdivTol * gSubdivTol) { |
| return 0; |
| } else { |
| static const int kMaxSub = 4; |
| // subdividing the quad reduces d by 4. so we want x = log4(d/tol) |
| // = log4(d*d/tol*tol)/2 |
| // = log2(d*d/tol*tol) |
| |
| // +1 since we're ignoring the mantissa contribution. |
| int log = get_float_exp(dsqd/(gSubdivTol*gSubdivTol)) + 1; |
| log = SkTMin(SkTMax(0, log), kMaxSub); |
| return log; |
| } |
| } |
| |
| /** |
| * Generates the lines and quads to be rendered. Lines are always recorded in |
| * device space. We will do a device space bloat to account for the 1pixel |
| * thickness. |
| * Quads are recorded in device space unless m contains |
| * perspective, then in they are in src space. We do this because we will |
| * subdivide large quads to reduce over-fill. This subdivision has to be |
| * performed before applying the perspective matrix. |
| */ |
| static int gather_lines_and_quads(const SkPath& path, |
| const SkMatrix& m, |
| const SkIRect& devClipBounds, |
| SkScalar capLength, |
| GrAAHairLinePathRenderer::PtArray* lines, |
| GrAAHairLinePathRenderer::PtArray* quads, |
| GrAAHairLinePathRenderer::PtArray* conics, |
| GrAAHairLinePathRenderer::IntArray* quadSubdivCnts, |
| GrAAHairLinePathRenderer::FloatArray* conicWeights) { |
| SkPath::Iter iter(path, false); |
| |
| int totalQuadCount = 0; |
| SkRect bounds; |
| SkIRect ibounds; |
| |
| bool persp = m.hasPerspective(); |
| |
| // Whenever a degenerate, zero-length contour is encountered, this code will insert a |
| // 'capLength' x-aligned line segment. Since this is rendering hairlines it is hoped this will |
| // suffice for AA square & circle capping. |
| int verbsInContour = 0; // Does not count moves |
| bool seenZeroLengthVerb = false; |
| SkPoint zeroVerbPt; |
| |
| for (;;) { |
| SkPoint pathPts[4]; |
| SkPoint devPts[4]; |
| SkPath::Verb verb = iter.next(pathPts, false); |
| switch (verb) { |
| case SkPath::kConic_Verb: { |
| SkConic dst[4]; |
| // We chop the conics to create tighter clipping to hide error |
| // that appears near max curvature of very thin conics. Thin |
| // hyperbolas with high weight still show error. |
| int conicCnt = chop_conic(pathPts, dst, iter.conicWeight()); |
| for (int i = 0; i < conicCnt; ++i) { |
| SkPoint* chopPnts = dst[i].fPts; |
| m.mapPoints(devPts, chopPnts, 3); |
| bounds.setBounds(devPts, 3); |
| bounds.outset(SK_Scalar1, SK_Scalar1); |
| bounds.roundOut(&ibounds); |
| if (SkIRect::Intersects(devClipBounds, ibounds)) { |
| if (is_degen_quad_or_conic(devPts)) { |
| SkPoint* pts = lines->push_back_n(4); |
| pts[0] = devPts[0]; |
| pts[1] = devPts[1]; |
| pts[2] = devPts[1]; |
| pts[3] = devPts[2]; |
| if (verbsInContour == 0 && i == 0 && |
| pts[0] == pts[1] && pts[2] == pts[3]) { |
| seenZeroLengthVerb = true; |
| zeroVerbPt = pts[0]; |
| } |
| } else { |
| // when in perspective keep conics in src space |
| SkPoint* cPts = persp ? chopPnts : devPts; |
| SkPoint* pts = conics->push_back_n(3); |
| pts[0] = cPts[0]; |
| pts[1] = cPts[1]; |
| pts[2] = cPts[2]; |
| conicWeights->push_back() = dst[i].fW; |
| } |
| } |
| } |
| verbsInContour++; |
| break; |
| } |
| case SkPath::kMove_Verb: |
| // New contour (and last one was unclosed). If it was just a zero length drawing |
| // operation, and we're supposed to draw caps, then add a tiny line. |
| if (seenZeroLengthVerb && verbsInContour == 1 && capLength > 0) { |
| SkPoint* pts = lines->push_back_n(2); |
| pts[0] = SkPoint::Make(zeroVerbPt.fX - capLength, zeroVerbPt.fY); |
| pts[1] = SkPoint::Make(zeroVerbPt.fX + capLength, zeroVerbPt.fY); |
| } |
| verbsInContour = 0; |
| seenZeroLengthVerb = false; |
| break; |
| case SkPath::kLine_Verb: |
| m.mapPoints(devPts, pathPts, 2); |
| bounds.setBounds(devPts, 2); |
| bounds.outset(SK_Scalar1, SK_Scalar1); |
| bounds.roundOut(&ibounds); |
| if (SkIRect::Intersects(devClipBounds, ibounds)) { |
| SkPoint* pts = lines->push_back_n(2); |
| pts[0] = devPts[0]; |
| pts[1] = devPts[1]; |
| if (verbsInContour == 0 && pts[0] == pts[1]) { |
| seenZeroLengthVerb = true; |
| zeroVerbPt = pts[0]; |
| } |
| } |
| verbsInContour++; |
| break; |
| case SkPath::kQuad_Verb: { |
| SkPoint choppedPts[5]; |
| // Chopping the quad helps when the quad is either degenerate or nearly degenerate. |
| // When it is degenerate it allows the approximation with lines to work since the |
| // chop point (if there is one) will be at the parabola's vertex. In the nearly |
| // degenerate the QuadUVMatrix computed for the points is almost singular which |
| // can cause rendering artifacts. |
| int n = SkChopQuadAtMaxCurvature(pathPts, choppedPts); |
| for (int i = 0; i < n; ++i) { |
| SkPoint* quadPts = choppedPts + i * 2; |
| m.mapPoints(devPts, quadPts, 3); |
| bounds.setBounds(devPts, 3); |
| bounds.outset(SK_Scalar1, SK_Scalar1); |
| bounds.roundOut(&ibounds); |
| |
| if (SkIRect::Intersects(devClipBounds, ibounds)) { |
| int subdiv = num_quad_subdivs(devPts); |
| SkASSERT(subdiv >= -1); |
| if (-1 == subdiv) { |
| SkPoint* pts = lines->push_back_n(4); |
| pts[0] = devPts[0]; |
| pts[1] = devPts[1]; |
| pts[2] = devPts[1]; |
| pts[3] = devPts[2]; |
| if (verbsInContour == 0 && i == 0 && |
| pts[0] == pts[1] && pts[2] == pts[3]) { |
| seenZeroLengthVerb = true; |
| zeroVerbPt = pts[0]; |
| } |
| } else { |
| // when in perspective keep quads in src space |
| SkPoint* qPts = persp ? quadPts : devPts; |
| SkPoint* pts = quads->push_back_n(3); |
| pts[0] = qPts[0]; |
| pts[1] = qPts[1]; |
| pts[2] = qPts[2]; |
| quadSubdivCnts->push_back() = subdiv; |
| totalQuadCount += 1 << subdiv; |
| } |
| } |
| } |
| verbsInContour++; |
| break; |
| } |
| case SkPath::kCubic_Verb: |
| m.mapPoints(devPts, pathPts, 4); |
| bounds.setBounds(devPts, 4); |
| bounds.outset(SK_Scalar1, SK_Scalar1); |
| bounds.roundOut(&ibounds); |
| if (SkIRect::Intersects(devClipBounds, ibounds)) { |
| PREALLOC_PTARRAY(32) q; |
| // We convert cubics to quadratics (for now). |
| // In perspective have to do conversion in src space. |
| if (persp) { |
| SkScalar tolScale = |
| GrPathUtils::scaleToleranceToSrc(SK_Scalar1, m, path.getBounds()); |
| GrPathUtils::convertCubicToQuads(pathPts, tolScale, &q); |
| } else { |
| GrPathUtils::convertCubicToQuads(devPts, SK_Scalar1, &q); |
| } |
| for (int i = 0; i < q.count(); i += 3) { |
| SkPoint* qInDevSpace; |
| // bounds has to be calculated in device space, but q is |
| // in src space when there is perspective. |
| if (persp) { |
| m.mapPoints(devPts, &q[i], 3); |
| bounds.setBounds(devPts, 3); |
| qInDevSpace = devPts; |
| } else { |
| bounds.setBounds(&q[i], 3); |
| qInDevSpace = &q[i]; |
| } |
| bounds.outset(SK_Scalar1, SK_Scalar1); |
| bounds.roundOut(&ibounds); |
| if (SkIRect::Intersects(devClipBounds, ibounds)) { |
| int subdiv = num_quad_subdivs(qInDevSpace); |
| SkASSERT(subdiv >= -1); |
| if (-1 == subdiv) { |
| SkPoint* pts = lines->push_back_n(4); |
| // lines should always be in device coords |
| pts[0] = qInDevSpace[0]; |
| pts[1] = qInDevSpace[1]; |
| pts[2] = qInDevSpace[1]; |
| pts[3] = qInDevSpace[2]; |
| if (verbsInContour == 0 && i == 0 && |
| pts[0] == pts[1] && pts[2] == pts[3]) { |
| seenZeroLengthVerb = true; |
| zeroVerbPt = pts[0]; |
| } |
| } else { |
| SkPoint* pts = quads->push_back_n(3); |
| // q is already in src space when there is no |
| // perspective and dev coords otherwise. |
| pts[0] = q[0 + i]; |
| pts[1] = q[1 + i]; |
| pts[2] = q[2 + i]; |
| quadSubdivCnts->push_back() = subdiv; |
| totalQuadCount += 1 << subdiv; |
| } |
| } |
| } |
| } |
| verbsInContour++; |
| break; |
| case SkPath::kClose_Verb: |
| // Contour is closed, so we don't need to grow the starting line, unless it's |
| // *just* a zero length subpath. (SVG Spec 11.4, 'stroke'). |
| if (capLength > 0) { |
| if (seenZeroLengthVerb && verbsInContour == 1) { |
| SkPoint* pts = lines->push_back_n(2); |
| pts[0] = SkPoint::Make(zeroVerbPt.fX - capLength, zeroVerbPt.fY); |
| pts[1] = SkPoint::Make(zeroVerbPt.fX + capLength, zeroVerbPt.fY); |
| } else if (verbsInContour == 0) { |
| // Contour was (moveTo, close). Add a line. |
| m.mapPoints(devPts, pathPts, 1); |
| devPts[1] = devPts[0]; |
| bounds.setBounds(devPts, 2); |
| bounds.outset(SK_Scalar1, SK_Scalar1); |
| bounds.roundOut(&ibounds); |
| if (SkIRect::Intersects(devClipBounds, ibounds)) { |
| SkPoint* pts = lines->push_back_n(2); |
| pts[0] = SkPoint::Make(devPts[0].fX - capLength, devPts[0].fY); |
| pts[1] = SkPoint::Make(devPts[1].fX + capLength, devPts[1].fY); |
| } |
| } |
| } |
| break; |
| case SkPath::kDone_Verb: |
| if (seenZeroLengthVerb && verbsInContour == 1 && capLength > 0) { |
| // Path ended with a dangling (moveTo, line|quad|etc). If the final verb is |
| // degenerate, we need to draw a line. |
| SkPoint* pts = lines->push_back_n(2); |
| pts[0] = SkPoint::Make(zeroVerbPt.fX - capLength, zeroVerbPt.fY); |
| pts[1] = SkPoint::Make(zeroVerbPt.fX + capLength, zeroVerbPt.fY); |
| } |
| return totalQuadCount; |
| } |
| } |
| } |
| |
| struct LineVertex { |
| SkPoint fPos; |
| float fCoverage; |
| }; |
| |
| struct BezierVertex { |
| SkPoint fPos; |
| union { |
| struct { |
| SkScalar fKLM[3]; |
| } fConic; |
| SkVector fQuadCoord; |
| struct { |
| SkScalar fBogus[4]; |
| }; |
| }; |
| }; |
| |
| GR_STATIC_ASSERT(sizeof(BezierVertex) == 3 * sizeof(SkPoint)); |
| |
| static void intersect_lines(const SkPoint& ptA, const SkVector& normA, |
| const SkPoint& ptB, const SkVector& normB, |
| SkPoint* result) { |
| |
| SkScalar lineAW = -normA.dot(ptA); |
| SkScalar lineBW = -normB.dot(ptB); |
| |
| SkScalar wInv = normA.fX * normB.fY - normA.fY * normB.fX; |
| wInv = SkScalarInvert(wInv); |
| |
| result->fX = normA.fY * lineBW - lineAW * normB.fY; |
| result->fX *= wInv; |
| |
| result->fY = lineAW * normB.fX - normA.fX * lineBW; |
| result->fY *= wInv; |
| } |
| |
| static void set_uv_quad(const SkPoint qpts[3], BezierVertex verts[kQuadNumVertices]) { |
| // this should be in the src space, not dev coords, when we have perspective |
| GrPathUtils::QuadUVMatrix DevToUV(qpts); |
| DevToUV.apply<kQuadNumVertices, sizeof(BezierVertex), sizeof(SkPoint)>(verts); |
| } |
| |
| static void bloat_quad(const SkPoint qpts[3], const SkMatrix* toDevice, |
| const SkMatrix* toSrc, BezierVertex verts[kQuadNumVertices]) { |
| SkASSERT(!toDevice == !toSrc); |
| // original quad is specified by tri a,b,c |
| SkPoint a = qpts[0]; |
| SkPoint b = qpts[1]; |
| SkPoint c = qpts[2]; |
| |
| if (toDevice) { |
| toDevice->mapPoints(&a, 1); |
| toDevice->mapPoints(&b, 1); |
| toDevice->mapPoints(&c, 1); |
| } |
| // make a new poly where we replace a and c by a 1-pixel wide edges orthog |
| // to edges ab and bc: |
| // |
| // before | after |
| // | b0 |
| // b | |
| // | |
| // | a0 c0 |
| // a c | a1 c1 |
| // |
| // edges a0->b0 and b0->c0 are parallel to original edges a->b and b->c, |
| // respectively. |
| BezierVertex& a0 = verts[0]; |
| BezierVertex& a1 = verts[1]; |
| BezierVertex& b0 = verts[2]; |
| BezierVertex& c0 = verts[3]; |
| BezierVertex& c1 = verts[4]; |
| |
| SkVector ab = b; |
| ab -= a; |
| SkVector ac = c; |
| ac -= a; |
| SkVector cb = b; |
| cb -= c; |
| |
| // We should have already handled degenerates |
| SkASSERT(ab.length() > 0 && cb.length() > 0); |
| |
| ab.normalize(); |
| SkVector abN; |
| abN.setOrthog(ab, SkVector::kLeft_Side); |
| if (abN.dot(ac) > 0) { |
| abN.negate(); |
| } |
| |
| cb.normalize(); |
| SkVector cbN; |
| cbN.setOrthog(cb, SkVector::kLeft_Side); |
| if (cbN.dot(ac) < 0) { |
| cbN.negate(); |
| } |
| |
| a0.fPos = a; |
| a0.fPos += abN; |
| a1.fPos = a; |
| a1.fPos -= abN; |
| |
| c0.fPos = c; |
| c0.fPos += cbN; |
| c1.fPos = c; |
| c1.fPos -= cbN; |
| |
| intersect_lines(a0.fPos, abN, c0.fPos, cbN, &b0.fPos); |
| |
| if (toSrc) { |
| toSrc->mapPointsWithStride(&verts[0].fPos, sizeof(BezierVertex), kQuadNumVertices); |
| } |
| } |
| |
| // Equations based off of Loop-Blinn Quadratic GPU Rendering |
| // Input Parametric: |
| // 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) |
| // Output Implicit: |
| // f(x, y, w) = f(P) = K^2 - LM |
| // K = dot(k, P), L = dot(l, P), M = dot(m, P) |
| // k, l, m are calculated in function GrPathUtils::getConicKLM |
| static void set_conic_coeffs(const SkPoint p[3], BezierVertex verts[kQuadNumVertices], |
| const SkScalar weight) { |
| SkMatrix klm; |
| |
| GrPathUtils::getConicKLM(p, weight, &klm); |
| |
| for (int i = 0; i < kQuadNumVertices; ++i) { |
| const SkScalar pt3[3] = {verts[i].fPos.x(), verts[i].fPos.y(), 1.f}; |
| klm.mapHomogeneousPoints(verts[i].fConic.fKLM, pt3, 1); |
| } |
| } |
| |
| static void add_conics(const SkPoint p[3], |
| const SkScalar weight, |
| const SkMatrix* toDevice, |
| const SkMatrix* toSrc, |
| BezierVertex** vert) { |
| bloat_quad(p, toDevice, toSrc, *vert); |
| set_conic_coeffs(p, *vert, weight); |
| *vert += kQuadNumVertices; |
| } |
| |
| static void add_quads(const SkPoint p[3], |
| int subdiv, |
| const SkMatrix* toDevice, |
| const SkMatrix* toSrc, |
| BezierVertex** vert) { |
| SkASSERT(subdiv >= 0); |
| if (subdiv) { |
| SkPoint newP[5]; |
| SkChopQuadAtHalf(p, newP); |
| add_quads(newP + 0, subdiv-1, toDevice, toSrc, vert); |
| add_quads(newP + 2, subdiv-1, toDevice, toSrc, vert); |
| } else { |
| bloat_quad(p, toDevice, toSrc, *vert); |
| set_uv_quad(p, *vert); |
| *vert += kQuadNumVertices; |
| } |
| } |
| |
| static void add_line(const SkPoint p[2], |
| const SkMatrix* toSrc, |
| uint8_t coverage, |
| LineVertex** vert) { |
| const SkPoint& a = p[0]; |
| const SkPoint& b = p[1]; |
| |
| SkVector ortho, vec = b; |
| vec -= a; |
| |
| if (vec.setLength(SK_ScalarHalf)) { |
| // Create a vector orthogonal to 'vec' and of unit length |
| ortho.fX = 2.0f * vec.fY; |
| ortho.fY = -2.0f * vec.fX; |
| |
| float floatCoverage = GrNormalizeByteToFloat(coverage); |
| |
| (*vert)[0].fPos = a; |
| (*vert)[0].fCoverage = floatCoverage; |
| (*vert)[1].fPos = b; |
| (*vert)[1].fCoverage = floatCoverage; |
| (*vert)[2].fPos = a - vec + ortho; |
| (*vert)[2].fCoverage = 0; |
| (*vert)[3].fPos = b + vec + ortho; |
| (*vert)[3].fCoverage = 0; |
| (*vert)[4].fPos = a - vec - ortho; |
| (*vert)[4].fCoverage = 0; |
| (*vert)[5].fPos = b + vec - ortho; |
| (*vert)[5].fCoverage = 0; |
| |
| if (toSrc) { |
| toSrc->mapPointsWithStride(&(*vert)->fPos, |
| sizeof(LineVertex), |
| kLineSegNumVertices); |
| } |
| } else { |
| // just make it degenerate and likely offscreen |
| for (int i = 0; i < kLineSegNumVertices; ++i) { |
| (*vert)[i].fPos.set(SK_ScalarMax, SK_ScalarMax); |
| } |
| } |
| |
| *vert += kLineSegNumVertices; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrAAHairLinePathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const { |
| if (GrAAType::kCoverage != args.fAAType) { |
| return false; |
| } |
| |
| if (!IsStrokeHairlineOrEquivalent(args.fShape->style(), *args.fViewMatrix, nullptr)) { |
| return false; |
| } |
| |
| // We don't currently handle dashing in this class though perhaps we should. |
| if (args.fShape->style().pathEffect()) { |
| return false; |
| } |
| |
| if (SkPath::kLine_SegmentMask == args.fShape->segmentMask() || |
| args.fCaps->shaderCaps()->shaderDerivativeSupport()) { |
| return true; |
| } |
| |
| return false; |
| } |
| |
| template <class VertexType> |
| bool check_bounds(const SkMatrix& viewMatrix, const SkRect& devBounds, void* vertices, int vCount) |
| { |
| SkRect tolDevBounds = devBounds; |
| // The bounds ought to be tight, but in perspective the below code runs the verts |
| // through the view matrix to get back to dev coords, which can introduce imprecision. |
| if (viewMatrix.hasPerspective()) { |
| tolDevBounds.outset(SK_Scalar1 / 1000, SK_Scalar1 / 1000); |
| } else { |
| // Non-persp matrices cause this path renderer to draw in device space. |
| SkASSERT(viewMatrix.isIdentity()); |
| } |
| SkRect actualBounds; |
| |
| VertexType* verts = reinterpret_cast<VertexType*>(vertices); |
| bool first = true; |
| for (int i = 0; i < vCount; ++i) { |
| SkPoint pos = verts[i].fPos; |
| // This is a hack to workaround the fact that we move some degenerate segments offscreen. |
| if (SK_ScalarMax == pos.fX) { |
| continue; |
| } |
| viewMatrix.mapPoints(&pos, 1); |
| if (first) { |
| actualBounds.set(pos.fX, pos.fY, pos.fX, pos.fY); |
| first = false; |
| } else { |
| actualBounds.growToInclude(pos.fX, pos.fY); |
| } |
| } |
| if (!first) { |
| return tolDevBounds.contains(actualBounds); |
| } |
| |
| return true; |
| } |
| |
| namespace { |
| |
| class AAHairlineOp final : public GrMeshDrawOp { |
| private: |
| using Helper = GrSimpleMeshDrawOpHelperWithStencil; |
| |
| public: |
| DEFINE_OP_CLASS_ID |
| |
| static std::unique_ptr<GrDrawOp> Make(GrPaint&& paint, |
| const SkMatrix& viewMatrix, |
| const SkPath& path, |
| const GrStyle& style, |
| const SkIRect& devClipBounds, |
| const GrUserStencilSettings* stencilSettings) { |
| SkScalar hairlineCoverage; |
| uint8_t newCoverage = 0xff; |
| if (GrPathRenderer::IsStrokeHairlineOrEquivalent(style, viewMatrix, &hairlineCoverage)) { |
| newCoverage = SkScalarRoundToInt(hairlineCoverage * 0xff); |
| } |
| |
| const SkStrokeRec& stroke = style.strokeRec(); |
| SkScalar capLength = SkPaint::kButt_Cap != stroke.getCap() ? hairlineCoverage * 0.5f : 0.0f; |
| |
| return Helper::FactoryHelper<AAHairlineOp>(std::move(paint), newCoverage, viewMatrix, path, |
| devClipBounds, capLength, stencilSettings); |
| } |
| |
| AAHairlineOp(const Helper::MakeArgs& helperArgs, |
| GrColor color, |
| uint8_t coverage, |
| const SkMatrix& viewMatrix, |
| const SkPath& path, |
| SkIRect devClipBounds, |
| SkScalar capLength, |
| const GrUserStencilSettings* stencilSettings) |
| : INHERITED(ClassID()) |
| , fHelper(helperArgs, GrAAType::kCoverage, stencilSettings) |
| , fColor(color) |
| , fCoverage(coverage) { |
| fPaths.emplace_back(PathData{viewMatrix, path, devClipBounds, capLength}); |
| |
| this->setTransformedBounds(path.getBounds(), viewMatrix, HasAABloat::kYes, |
| IsZeroArea::kYes); |
| } |
| |
| const char* name() const override { return "AAHairlineOp"; } |
| |
| SkString dumpInfo() const override { |
| SkString string; |
| string.appendf("Color: 0x%08x Coverage: 0x%02x, Count: %d\n", fColor, fCoverage, |
| fPaths.count()); |
| string += INHERITED::dumpInfo(); |
| string += fHelper.dumpInfo(); |
| return string; |
| } |
| |
| FixedFunctionFlags fixedFunctionFlags() const override { return fHelper.fixedFunctionFlags(); } |
| |
| RequiresDstTexture finalize(const GrCaps& caps, const GrAppliedClip* clip) override { |
| return fHelper.xpRequiresDstTexture(caps, clip, GrProcessorAnalysisCoverage::kSingleChannel, |
| &fColor); |
| } |
| |
| private: |
| void onPrepareDraws(Target*) const override; |
| |
| typedef SkTArray<SkPoint, true> PtArray; |
| typedef SkTArray<int, true> IntArray; |
| typedef SkTArray<float, true> FloatArray; |
| |
| bool onCombineIfPossible(GrOp* t, const GrCaps& caps) override { |
| AAHairlineOp* that = t->cast<AAHairlineOp>(); |
| |
| if (!fHelper.isCompatible(that->fHelper, caps, this->bounds(), that->bounds())) { |
| return false; |
| } |
| |
| if (this->viewMatrix().hasPerspective() != that->viewMatrix().hasPerspective()) { |
| return false; |
| } |
| |
| // We go to identity if we don't have perspective |
| if (this->viewMatrix().hasPerspective() && |
| !this->viewMatrix().cheapEqualTo(that->viewMatrix())) { |
| return false; |
| } |
| |
| // TODO we can actually combine hairlines if they are the same color in a kind of bulk |
| // method but we haven't implemented this yet |
| // TODO investigate going to vertex color and coverage? |
| if (this->coverage() != that->coverage()) { |
| return false; |
| } |
| |
| if (this->color() != that->color()) { |
| return false; |
| } |
| |
| if (fHelper.usesLocalCoords() && !this->viewMatrix().cheapEqualTo(that->viewMatrix())) { |
| return false; |
| } |
| |
| fPaths.push_back_n(that->fPaths.count(), that->fPaths.begin()); |
| this->joinBounds(*that); |
| return true; |
| } |
| |
| GrColor color() const { return fColor; } |
| uint8_t coverage() const { return fCoverage; } |
| const SkMatrix& viewMatrix() const { return fPaths[0].fViewMatrix; } |
| |
| struct PathData { |
| SkMatrix fViewMatrix; |
| SkPath fPath; |
| SkIRect fDevClipBounds; |
| SkScalar fCapLength; |
| }; |
| |
| SkSTArray<1, PathData, true> fPaths; |
| Helper fHelper; |
| GrColor fColor; |
| uint8_t fCoverage; |
| |
| typedef GrMeshDrawOp INHERITED; |
| }; |
| |
| } // anonymous namespace |
| |
| void AAHairlineOp::onPrepareDraws(Target* target) const { |
| // Setup the viewmatrix and localmatrix for the GrGeometryProcessor. |
| SkMatrix invert; |
| if (!this->viewMatrix().invert(&invert)) { |
| return; |
| } |
| |
| // we will transform to identity space if the viewmatrix does not have perspective |
| bool hasPerspective = this->viewMatrix().hasPerspective(); |
| const SkMatrix* geometryProcessorViewM = &SkMatrix::I(); |
| const SkMatrix* geometryProcessorLocalM = &invert; |
| const SkMatrix* toDevice = nullptr; |
| const SkMatrix* toSrc = nullptr; |
| if (hasPerspective) { |
| geometryProcessorViewM = &this->viewMatrix(); |
| geometryProcessorLocalM = &SkMatrix::I(); |
| toDevice = &this->viewMatrix(); |
| toSrc = &invert; |
| } |
| |
| // This is hand inlined for maximum performance. |
| PREALLOC_PTARRAY(128) lines; |
| PREALLOC_PTARRAY(128) quads; |
| PREALLOC_PTARRAY(128) conics; |
| IntArray qSubdivs; |
| FloatArray cWeights; |
| int quadCount = 0; |
| |
| int instanceCount = fPaths.count(); |
| for (int i = 0; i < instanceCount; i++) { |
| const PathData& args = fPaths[i]; |
| quadCount += gather_lines_and_quads(args.fPath, args.fViewMatrix, args.fDevClipBounds, |
| args.fCapLength, &lines, &quads, &conics, &qSubdivs, |
| &cWeights); |
| } |
| |
| int lineCount = lines.count() / 2; |
| int conicCount = conics.count() / 3; |
| |
| const GrPipeline* pipeline = fHelper.makePipeline(target); |
| // do lines first |
| if (lineCount) { |
| sk_sp<GrGeometryProcessor> lineGP; |
| { |
| using namespace GrDefaultGeoProcFactory; |
| |
| Color color(this->color()); |
| LocalCoords localCoords(fHelper.usesLocalCoords() ? LocalCoords::kUsePosition_Type |
| : LocalCoords::kUnused_Type); |
| localCoords.fMatrix = geometryProcessorLocalM; |
| lineGP = GrDefaultGeoProcFactory::Make(color, Coverage::kAttribute_Type, localCoords, |
| *geometryProcessorViewM); |
| } |
| |
| sk_sp<const GrBuffer> linesIndexBuffer( |
| ref_lines_index_buffer(target->resourceProvider())); |
| |
| const GrBuffer* vertexBuffer; |
| int firstVertex; |
| |
| size_t vertexStride = lineGP->getVertexStride(); |
| int vertexCount = kLineSegNumVertices * lineCount; |
| LineVertex* verts = reinterpret_cast<LineVertex*>( |
| target->makeVertexSpace(vertexStride, vertexCount, &vertexBuffer, &firstVertex)); |
| |
| if (!verts|| !linesIndexBuffer) { |
| SkDebugf("Could not allocate vertices\n"); |
| return; |
| } |
| |
| SkASSERT(lineGP->getVertexStride() == sizeof(LineVertex)); |
| |
| for (int i = 0; i < lineCount; ++i) { |
| add_line(&lines[2*i], toSrc, this->coverage(), &verts); |
| } |
| |
| GrMesh mesh(GrPrimitiveType::kTriangles); |
| mesh.setIndexedPatterned(linesIndexBuffer.get(), kIdxsPerLineSeg, kLineSegNumVertices, |
| lineCount, kLineSegsNumInIdxBuffer); |
| mesh.setVertexData(vertexBuffer, firstVertex); |
| target->draw(lineGP.get(), pipeline, mesh); |
| } |
| |
| if (quadCount || conicCount) { |
| sk_sp<GrGeometryProcessor> quadGP(GrQuadEffect::Make(this->color(), |
| *geometryProcessorViewM, |
| kHairlineAA_GrProcessorEdgeType, |
| target->caps(), |
| *geometryProcessorLocalM, |
| fHelper.usesLocalCoords(), |
| this->coverage())); |
| |
| sk_sp<GrGeometryProcessor> conicGP(GrConicEffect::Make(this->color(), |
| *geometryProcessorViewM, |
| kHairlineAA_GrProcessorEdgeType, |
| target->caps(), |
| *geometryProcessorLocalM, |
| fHelper.usesLocalCoords(), |
| this->coverage())); |
| |
| const GrBuffer* vertexBuffer; |
| int firstVertex; |
| |
| sk_sp<const GrBuffer> quadsIndexBuffer( |
| ref_quads_index_buffer(target->resourceProvider())); |
| |
| size_t vertexStride = sizeof(BezierVertex); |
| int vertexCount = kQuadNumVertices * quadCount + kQuadNumVertices * conicCount; |
| void *vertices = target->makeVertexSpace(vertexStride, vertexCount, |
| &vertexBuffer, &firstVertex); |
| |
| if (!vertices || !quadsIndexBuffer) { |
| SkDebugf("Could not allocate vertices\n"); |
| return; |
| } |
| |
| // Setup vertices |
| BezierVertex* bezVerts = reinterpret_cast<BezierVertex*>(vertices); |
| |
| int unsubdivQuadCnt = quads.count() / 3; |
| for (int i = 0; i < unsubdivQuadCnt; ++i) { |
| SkASSERT(qSubdivs[i] >= 0); |
| add_quads(&quads[3*i], qSubdivs[i], toDevice, toSrc, &bezVerts); |
| } |
| |
| // Start Conics |
| for (int i = 0; i < conicCount; ++i) { |
| add_conics(&conics[3*i], cWeights[i], toDevice, toSrc, &bezVerts); |
| } |
| |
| if (quadCount > 0) { |
| GrMesh mesh(GrPrimitiveType::kTriangles); |
| mesh.setIndexedPatterned(quadsIndexBuffer.get(), kIdxsPerQuad, kQuadNumVertices, |
| quadCount, kQuadsNumInIdxBuffer); |
| mesh.setVertexData(vertexBuffer, firstVertex); |
| target->draw(quadGP.get(), pipeline, mesh); |
| firstVertex += quadCount * kQuadNumVertices; |
| } |
| |
| if (conicCount > 0) { |
| GrMesh mesh(GrPrimitiveType::kTriangles); |
| mesh.setIndexedPatterned(quadsIndexBuffer.get(), kIdxsPerQuad, kQuadNumVertices, |
| conicCount, kQuadsNumInIdxBuffer); |
| mesh.setVertexData(vertexBuffer, firstVertex); |
| target->draw(conicGP.get(), pipeline, mesh); |
| } |
| } |
| } |
| |
| bool GrAAHairLinePathRenderer::onDrawPath(const DrawPathArgs& args) { |
| GR_AUDIT_TRAIL_AUTO_FRAME(args.fRenderTargetContext->auditTrail(), |
| "GrAAHairlinePathRenderer::onDrawPath"); |
| SkASSERT(GrFSAAType::kUnifiedMSAA != args.fRenderTargetContext->fsaaType()); |
| |
| SkIRect devClipBounds; |
| args.fClip->getConservativeBounds(args.fRenderTargetContext->width(), |
| args.fRenderTargetContext->height(), |
| &devClipBounds); |
| SkPath path; |
| args.fShape->asPath(&path); |
| std::unique_ptr<GrDrawOp> op = |
| AAHairlineOp::Make(std::move(args.fPaint), *args.fViewMatrix, path, |
| args.fShape->style(), devClipBounds, args.fUserStencilSettings); |
| args.fRenderTargetContext->addDrawOp(*args.fClip, std::move(op)); |
| return true; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| #if GR_TEST_UTILS |
| |
| GR_DRAW_OP_TEST_DEFINE(AAHairlineOp) { |
| SkMatrix viewMatrix = GrTest::TestMatrix(random); |
| SkPath path = GrTest::TestPath(random); |
| SkIRect devClipBounds; |
| devClipBounds.setEmpty(); |
| return AAHairlineOp::Make(std::move(paint), viewMatrix, path, GrStyle::SimpleHairline(), |
| devClipBounds, GrGetRandomStencil(random, context)); |
| } |
| |
| #endif |
