michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "GrAAHairLinePathRenderer.h"
michael@0: 
michael@0: #include "GrContext.h"
michael@0: #include "GrDrawState.h"
michael@0: #include "GrDrawTargetCaps.h"
michael@0: #include "GrEffect.h"
michael@0: #include "GrGpu.h"
michael@0: #include "GrIndexBuffer.h"
michael@0: #include "GrPathUtils.h"
michael@0: #include "GrTBackendEffectFactory.h"
michael@0: #include "SkGeometry.h"
michael@0: #include "SkStroke.h"
michael@0: #include "SkTemplates.h"
michael@0: 
michael@0: #include "effects/GrBezierEffect.h"
michael@0: 
michael@0: namespace {
michael@0: // quadratics are rendered as 5-sided polys in order to bound the
michael@0: // AA stroke around the center-curve. See comments in push_quad_index_buffer and
michael@0: // bloat_quad. Quadratics and conics share an index buffer
michael@0: static const int kVertsPerQuad = 5;
michael@0: static const int kIdxsPerQuad = 9;
michael@0: 
michael@0: // lines are rendered as:
michael@0: //      *______________*
michael@0: //      |\ -_______   /|
michael@0: //      | \        \ / |
michael@0: //      |  *--------*  |
michael@0: //      | /  ______/ \ |
michael@0: //      */_-__________\*
michael@0: // For: 6 vertices and 18 indices (for 6 triangles)
michael@0: static const int kVertsPerLineSeg = 6;
michael@0: static const int kIdxsPerLineSeg = 18;
michael@0: 
michael@0: static const int kNumQuadsInIdxBuffer = 256;
michael@0: static const size_t kQuadIdxSBufize = kIdxsPerQuad *
michael@0:                                       sizeof(uint16_t) *
michael@0:                                       kNumQuadsInIdxBuffer;
michael@0: 
michael@0: static const int kNumLineSegsInIdxBuffer = 256;
michael@0: static const size_t kLineSegIdxSBufize = kIdxsPerLineSeg *
michael@0:                                          sizeof(uint16_t) *
michael@0:                                          kNumLineSegsInIdxBuffer;
michael@0: 
michael@0: static bool push_quad_index_data(GrIndexBuffer* qIdxBuffer) {
michael@0:     uint16_t* data = (uint16_t*) qIdxBuffer->lock();
michael@0:     bool tempData = NULL == data;
michael@0:     if (tempData) {
michael@0:         data = SkNEW_ARRAY(uint16_t, kNumQuadsInIdxBuffer * kIdxsPerQuad);
michael@0:     }
michael@0:     for (int i = 0; i < kNumQuadsInIdxBuffer; ++i) {
michael@0: 
michael@0:         // Each quadratic is rendered as a five sided polygon. This poly bounds
michael@0:         // the quadratic's bounding triangle but has been expanded so that the
michael@0:         // 1-pixel wide area around the curve is inside the poly.
michael@0:         // If a,b,c are the original control points then the poly a0,b0,c0,c1,a1
michael@0:         // that is rendered would look like this:
michael@0:         //              b0
michael@0:         //              b
michael@0:         //
michael@0:         //     a0              c0
michael@0:         //      a            c
michael@0:         //       a1       c1
michael@0:         // Each is drawn as three triangles specified by these 9 indices:
michael@0:         int baseIdx = i * kIdxsPerQuad;
michael@0:         uint16_t baseVert = (uint16_t)(i * kVertsPerQuad);
michael@0:         data[0 + baseIdx] = baseVert + 0; // a0
michael@0:         data[1 + baseIdx] = baseVert + 1; // a1
michael@0:         data[2 + baseIdx] = baseVert + 2; // b0
michael@0:         data[3 + baseIdx] = baseVert + 2; // b0
michael@0:         data[4 + baseIdx] = baseVert + 4; // c1
michael@0:         data[5 + baseIdx] = baseVert + 3; // c0
michael@0:         data[6 + baseIdx] = baseVert + 1; // a1
michael@0:         data[7 + baseIdx] = baseVert + 4; // c1
michael@0:         data[8 + baseIdx] = baseVert + 2; // b0
michael@0:     }
michael@0:     if (tempData) {
michael@0:         bool ret = qIdxBuffer->updateData(data, kQuadIdxSBufize);
michael@0:         delete[] data;
michael@0:         return ret;
michael@0:     } else {
michael@0:         qIdxBuffer->unlock();
michael@0:         return true;
michael@0:     }
michael@0: }
michael@0: 
michael@0: static bool push_line_index_data(GrIndexBuffer* lIdxBuffer) {
michael@0:     uint16_t* data = (uint16_t*) lIdxBuffer->lock();
michael@0:     bool tempData = NULL == data;
michael@0:     if (tempData) {
michael@0:         data = SkNEW_ARRAY(uint16_t, kNumLineSegsInIdxBuffer * kIdxsPerLineSeg);
michael@0:     }
michael@0:     for (int i = 0; i < kNumLineSegsInIdxBuffer; ++i) {
michael@0:         // Each line segment is rendered as two quads and two triangles.
michael@0:         // p0 and p1 have alpha = 1 while all other points have alpha = 0.
michael@0:         // The four external points are offset 1 pixel perpendicular to the
michael@0:         // line and half a pixel parallel to the line.
michael@0:         //
michael@0:         // p4                  p5
michael@0:         //      p0         p1
michael@0:         // p2                  p3
michael@0:         //
michael@0:         // Each is drawn as six triangles specified by these 18 indices:
michael@0:         int baseIdx = i * kIdxsPerLineSeg;
michael@0:         uint16_t baseVert = (uint16_t)(i * kVertsPerLineSeg);
michael@0:         data[0 + baseIdx] = baseVert + 0;
michael@0:         data[1 + baseIdx] = baseVert + 1;
michael@0:         data[2 + baseIdx] = baseVert + 3;
michael@0: 
michael@0:         data[3 + baseIdx] = baseVert + 0;
michael@0:         data[4 + baseIdx] = baseVert + 3;
michael@0:         data[5 + baseIdx] = baseVert + 2;
michael@0: 
michael@0:         data[6 + baseIdx] = baseVert + 0;
michael@0:         data[7 + baseIdx] = baseVert + 4;
michael@0:         data[8 + baseIdx] = baseVert + 5;
michael@0: 
michael@0:         data[9 + baseIdx] = baseVert + 0;
michael@0:         data[10+ baseIdx] = baseVert + 5;
michael@0:         data[11+ baseIdx] = baseVert + 1;
michael@0: 
michael@0:         data[12 + baseIdx] = baseVert + 0;
michael@0:         data[13 + baseIdx] = baseVert + 2;
michael@0:         data[14 + baseIdx] = baseVert + 4;
michael@0: 
michael@0:         data[15 + baseIdx] = baseVert + 1;
michael@0:         data[16 + baseIdx] = baseVert + 5;
michael@0:         data[17 + baseIdx] = baseVert + 3;
michael@0:     }
michael@0:     if (tempData) {
michael@0:         bool ret = lIdxBuffer->updateData(data, kLineSegIdxSBufize);
michael@0:         delete[] data;
michael@0:         return ret;
michael@0:     } else {
michael@0:         lIdxBuffer->unlock();
michael@0:         return true;
michael@0:     }
michael@0: }
michael@0: }
michael@0: 
michael@0: GrPathRenderer* GrAAHairLinePathRenderer::Create(GrContext* context) {
michael@0:     GrGpu* gpu = context->getGpu();
michael@0:     GrIndexBuffer* qIdxBuf = gpu->createIndexBuffer(kQuadIdxSBufize, false);
michael@0:     SkAutoTUnref<GrIndexBuffer> qIdxBuffer(qIdxBuf);
michael@0:     if (NULL == qIdxBuf || !push_quad_index_data(qIdxBuf)) {
michael@0:         return NULL;
michael@0:     }
michael@0:     GrIndexBuffer* lIdxBuf = gpu->createIndexBuffer(kLineSegIdxSBufize, false);
michael@0:     SkAutoTUnref<GrIndexBuffer> lIdxBuffer(lIdxBuf);
michael@0:     if (NULL == lIdxBuf || !push_line_index_data(lIdxBuf)) {
michael@0:         return NULL;
michael@0:     }
michael@0:     return SkNEW_ARGS(GrAAHairLinePathRenderer,
michael@0:                       (context, lIdxBuf, qIdxBuf));
michael@0: }
michael@0: 
michael@0: GrAAHairLinePathRenderer::GrAAHairLinePathRenderer(
michael@0:                                         const GrContext* context,
michael@0:                                         const GrIndexBuffer* linesIndexBuffer,
michael@0:                                         const GrIndexBuffer* quadsIndexBuffer) {
michael@0:     fLinesIndexBuffer = linesIndexBuffer;
michael@0:     linesIndexBuffer->ref();
michael@0:     fQuadsIndexBuffer = quadsIndexBuffer;
michael@0:     quadsIndexBuffer->ref();
michael@0: }
michael@0: 
michael@0: GrAAHairLinePathRenderer::~GrAAHairLinePathRenderer() {
michael@0:     fLinesIndexBuffer->unref();
michael@0:     fQuadsIndexBuffer->unref();
michael@0: }
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: #define PREALLOC_PTARRAY(N) SkSTArray<(N),SkPoint, true>
michael@0: 
michael@0: // Takes 178th time of logf on Z600 / VC2010
michael@0: int get_float_exp(float x) {
michael@0:     GR_STATIC_ASSERT(sizeof(int) == sizeof(float));
michael@0: #ifdef SK_DEBUG
michael@0:     static bool tested;
michael@0:     if (!tested) {
michael@0:         tested = true;
michael@0:         SkASSERT(get_float_exp(0.25f) == -2);
michael@0:         SkASSERT(get_float_exp(0.3f) == -2);
michael@0:         SkASSERT(get_float_exp(0.5f) == -1);
michael@0:         SkASSERT(get_float_exp(1.f) == 0);
michael@0:         SkASSERT(get_float_exp(2.f) == 1);
michael@0:         SkASSERT(get_float_exp(2.5f) == 1);
michael@0:         SkASSERT(get_float_exp(8.f) == 3);
michael@0:         SkASSERT(get_float_exp(100.f) == 6);
michael@0:         SkASSERT(get_float_exp(1000.f) == 9);
michael@0:         SkASSERT(get_float_exp(1024.f) == 10);
michael@0:         SkASSERT(get_float_exp(3000000.f) == 21);
michael@0:     }
michael@0: #endif
michael@0:     const int* iptr = (const int*)&x;
michael@0:     return (((*iptr) & 0x7f800000) >> 23) - 127;
michael@0: }
michael@0: 
michael@0: // Uses the max curvature function for quads to estimate
michael@0: // where to chop the conic. If the max curvature is not
michael@0: // found along the curve segment it will return 1 and
michael@0: // dst[0] is the original conic. If it returns 2 the dst[0]
michael@0: // and dst[1] are the two new conics.
michael@0: int split_conic(const SkPoint src[3], SkConic dst[2], const SkScalar weight) {
michael@0:     SkScalar t = SkFindQuadMaxCurvature(src);
michael@0:     if (t == 0) {
michael@0:         if (dst) {
michael@0:             dst[0].set(src, weight);
michael@0:         }
michael@0:         return 1;
michael@0:     } else {
michael@0:         if (dst) {
michael@0:             SkConic conic;
michael@0:             conic.set(src, weight);
michael@0:             conic.chopAt(t, dst);
michael@0:         }
michael@0:         return 2;
michael@0:     }
michael@0: }
michael@0: 
michael@0: // Calls split_conic on the entire conic and then once more on each subsection.
michael@0: // Most cases will result in either 1 conic (chop point is not within t range)
michael@0: // or 3 points (split once and then one subsection is split again).
michael@0: int chop_conic(const SkPoint src[3], SkConic dst[4], const SkScalar weight) {
michael@0:     SkConic dstTemp[2];
michael@0:     int conicCnt = split_conic(src, dstTemp, weight);
michael@0:     if (2 == conicCnt) {
michael@0:         int conicCnt2 = split_conic(dstTemp[0].fPts, dst, dstTemp[0].fW);
michael@0:         conicCnt = conicCnt2 + split_conic(dstTemp[1].fPts, &dst[conicCnt2], dstTemp[1].fW);
michael@0:     } else {
michael@0:         dst[0] = dstTemp[0];
michael@0:     }
michael@0:     return conicCnt;
michael@0: }
michael@0: 
michael@0: // returns 0 if quad/conic is degen or close to it
michael@0: // in this case approx the path with lines
michael@0: // otherwise returns 1
michael@0: int is_degen_quad_or_conic(const SkPoint p[3]) {
michael@0:     static const SkScalar gDegenerateToLineTol = SK_Scalar1;
michael@0:     static const SkScalar gDegenerateToLineTolSqd =
michael@0:         SkScalarMul(gDegenerateToLineTol, gDegenerateToLineTol);
michael@0: 
michael@0:     if (p[0].distanceToSqd(p[1]) < gDegenerateToLineTolSqd ||
michael@0:         p[1].distanceToSqd(p[2]) < gDegenerateToLineTolSqd) {
michael@0:         return 1;
michael@0:     }
michael@0: 
michael@0:     SkScalar dsqd = p[1].distanceToLineBetweenSqd(p[0], p[2]);
michael@0:     if (dsqd < gDegenerateToLineTolSqd) {
michael@0:         return 1;
michael@0:     }
michael@0: 
michael@0:     if (p[2].distanceToLineBetweenSqd(p[1], p[0]) < gDegenerateToLineTolSqd) {
michael@0:         return 1;
michael@0:     }
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: // we subdivide the quads to avoid huge overfill
michael@0: // if it returns -1 then should be drawn as lines
michael@0: int num_quad_subdivs(const SkPoint p[3]) {
michael@0:     static const SkScalar gDegenerateToLineTol = SK_Scalar1;
michael@0:     static const SkScalar gDegenerateToLineTolSqd =
michael@0:         SkScalarMul(gDegenerateToLineTol, gDegenerateToLineTol);
michael@0: 
michael@0:     if (p[0].distanceToSqd(p[1]) < gDegenerateToLineTolSqd ||
michael@0:         p[1].distanceToSqd(p[2]) < gDegenerateToLineTolSqd) {
michael@0:         return -1;
michael@0:     }
michael@0: 
michael@0:     SkScalar dsqd = p[1].distanceToLineBetweenSqd(p[0], p[2]);
michael@0:     if (dsqd < gDegenerateToLineTolSqd) {
michael@0:         return -1;
michael@0:     }
michael@0: 
michael@0:     if (p[2].distanceToLineBetweenSqd(p[1], p[0]) < gDegenerateToLineTolSqd) {
michael@0:         return -1;
michael@0:     }
michael@0: 
michael@0:     // tolerance of triangle height in pixels
michael@0:     // tuned on windows  Quadro FX 380 / Z600
michael@0:     // trade off of fill vs cpu time on verts
michael@0:     // maybe different when do this using gpu (geo or tess shaders)
michael@0:     static const SkScalar gSubdivTol = 175 * SK_Scalar1;
michael@0: 
michael@0:     if (dsqd <= SkScalarMul(gSubdivTol, gSubdivTol)) {
michael@0:         return 0;
michael@0:     } else {
michael@0:         static const int kMaxSub = 4;
michael@0:         // subdividing the quad reduces d by 4. so we want x = log4(d/tol)
michael@0:         // = log4(d*d/tol*tol)/2
michael@0:         // = log2(d*d/tol*tol)
michael@0: 
michael@0:         // +1 since we're ignoring the mantissa contribution.
michael@0:         int log = get_float_exp(dsqd/(gSubdivTol*gSubdivTol)) + 1;
michael@0:         log = GrMin(GrMax(0, log), kMaxSub);
michael@0:         return log;
michael@0:     }
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Generates the lines and quads to be rendered. Lines are always recorded in
michael@0:  * device space. We will do a device space bloat to account for the 1pixel
michael@0:  * thickness.
michael@0:  * Quads are recorded in device space unless m contains
michael@0:  * perspective, then in they are in src space. We do this because we will
michael@0:  * subdivide large quads to reduce over-fill. This subdivision has to be
michael@0:  * performed before applying the perspective matrix.
michael@0:  */
michael@0: int generate_lines_and_quads(const SkPath& path,
michael@0:                              const SkMatrix& m,
michael@0:                              const SkIRect& devClipBounds,
michael@0:                              GrAAHairLinePathRenderer::PtArray* lines,
michael@0:                              GrAAHairLinePathRenderer::PtArray* quads,
michael@0:                              GrAAHairLinePathRenderer::PtArray* conics,
michael@0:                              GrAAHairLinePathRenderer::IntArray* quadSubdivCnts,
michael@0:                              GrAAHairLinePathRenderer::FloatArray* conicWeights) {
michael@0:     SkPath::Iter iter(path, false);
michael@0: 
michael@0:     int totalQuadCount = 0;
michael@0:     SkRect bounds;
michael@0:     SkIRect ibounds;
michael@0: 
michael@0:     bool persp = m.hasPerspective();
michael@0: 
michael@0:     for (;;) {
michael@0:         GrPoint pathPts[4];
michael@0:         GrPoint devPts[4];
michael@0:         SkPath::Verb verb = iter.next(pathPts);
michael@0:         switch (verb) {
michael@0:             case SkPath::kConic_Verb: {
michael@0:                 SkConic dst[4];
michael@0:                 // We chop the conics to create tighter clipping to hide error
michael@0:                 // that appears near max curvature of very thin conics. Thin
michael@0:                 // hyperbolas with high weight still show error.
michael@0:                 int conicCnt = chop_conic(pathPts, dst, iter.conicWeight());
michael@0:                 for (int i = 0; i < conicCnt; ++i) {
michael@0:                     SkPoint* chopPnts = dst[i].fPts;
michael@0:                     m.mapPoints(devPts, chopPnts, 3);
michael@0:                     bounds.setBounds(devPts, 3);
michael@0:                     bounds.outset(SK_Scalar1, SK_Scalar1);
michael@0:                     bounds.roundOut(&ibounds);
michael@0:                     if (SkIRect::Intersects(devClipBounds, ibounds)) {
michael@0:                         if (is_degen_quad_or_conic(devPts)) {
michael@0:                             SkPoint* pts = lines->push_back_n(4);
michael@0:                             pts[0] = devPts[0];
michael@0:                             pts[1] = devPts[1];
michael@0:                             pts[2] = devPts[1];
michael@0:                             pts[3] = devPts[2];
michael@0:                         } else {
michael@0:                             // when in perspective keep conics in src space
michael@0:                             SkPoint* cPts = persp ? chopPnts : devPts;
michael@0:                             SkPoint* pts = conics->push_back_n(3);
michael@0:                             pts[0] = cPts[0];
michael@0:                             pts[1] = cPts[1];
michael@0:                             pts[2] = cPts[2];
michael@0:                             conicWeights->push_back() = dst[i].fW;
michael@0:                         }
michael@0:                     }
michael@0:                 }
michael@0:                 break;
michael@0:             }
michael@0:             case SkPath::kMove_Verb:
michael@0:                 break;
michael@0:             case SkPath::kLine_Verb:
michael@0:                 m.mapPoints(devPts, pathPts, 2);
michael@0:                 bounds.setBounds(devPts, 2);
michael@0:                 bounds.outset(SK_Scalar1, SK_Scalar1);
michael@0:                 bounds.roundOut(&ibounds);
michael@0:                 if (SkIRect::Intersects(devClipBounds, ibounds)) {
michael@0:                     SkPoint* pts = lines->push_back_n(2);
michael@0:                     pts[0] = devPts[0];
michael@0:                     pts[1] = devPts[1];
michael@0:                 }
michael@0:                 break;
michael@0:             case SkPath::kQuad_Verb: {
michael@0:                 SkPoint choppedPts[5];
michael@0:                 // Chopping the quad helps when the quad is either degenerate or nearly degenerate.
michael@0:                 // When it is degenerate it allows the approximation with lines to work since the
michael@0:                 // chop point (if there is one) will be at the parabola's vertex. In the nearly
michael@0:                 // degenerate the QuadUVMatrix computed for the points is almost singular which
michael@0:                 // can cause rendering artifacts.
michael@0:                 int n = SkChopQuadAtMaxCurvature(pathPts, choppedPts);
michael@0:                 for (int i = 0; i < n; ++i) {
michael@0:                     SkPoint* quadPts = choppedPts + i * 2;
michael@0:                     m.mapPoints(devPts, quadPts, 3);
michael@0:                     bounds.setBounds(devPts, 3);
michael@0:                     bounds.outset(SK_Scalar1, SK_Scalar1);
michael@0:                     bounds.roundOut(&ibounds);
michael@0: 
michael@0:                     if (SkIRect::Intersects(devClipBounds, ibounds)) {
michael@0:                         int subdiv = num_quad_subdivs(devPts);
michael@0:                         SkASSERT(subdiv >= -1);
michael@0:                         if (-1 == subdiv) {
michael@0:                             SkPoint* pts = lines->push_back_n(4);
michael@0:                             pts[0] = devPts[0];
michael@0:                             pts[1] = devPts[1];
michael@0:                             pts[2] = devPts[1];
michael@0:                             pts[3] = devPts[2];
michael@0:                         } else {
michael@0:                             // when in perspective keep quads in src space
michael@0:                             SkPoint* qPts = persp ? quadPts : devPts;
michael@0:                             SkPoint* pts = quads->push_back_n(3);
michael@0:                             pts[0] = qPts[0];
michael@0:                             pts[1] = qPts[1];
michael@0:                             pts[2] = qPts[2];
michael@0:                             quadSubdivCnts->push_back() = subdiv;
michael@0:                             totalQuadCount += 1 << subdiv;
michael@0:                         }
michael@0:                     }
michael@0:                 }
michael@0:                 break;
michael@0:             }
michael@0:             case SkPath::kCubic_Verb:
michael@0:                 m.mapPoints(devPts, pathPts, 4);
michael@0:                 bounds.setBounds(devPts, 4);
michael@0:                 bounds.outset(SK_Scalar1, SK_Scalar1);
michael@0:                 bounds.roundOut(&ibounds);
michael@0:                 if (SkIRect::Intersects(devClipBounds, ibounds)) {
michael@0:                     PREALLOC_PTARRAY(32) q;
michael@0:                     // we don't need a direction if we aren't constraining the subdivision
michael@0:                     static const SkPath::Direction kDummyDir = SkPath::kCCW_Direction;
michael@0:                     // We convert cubics to quadratics (for now).
michael@0:                     // In perspective have to do conversion in src space.
michael@0:                     if (persp) {
michael@0:                         SkScalar tolScale =
michael@0:                             GrPathUtils::scaleToleranceToSrc(SK_Scalar1, m,
michael@0:                                                              path.getBounds());
michael@0:                         GrPathUtils::convertCubicToQuads(pathPts, tolScale, false, kDummyDir, &q);
michael@0:                     } else {
michael@0:                         GrPathUtils::convertCubicToQuads(devPts, SK_Scalar1, false, kDummyDir, &q);
michael@0:                     }
michael@0:                     for (int i = 0; i < q.count(); i += 3) {
michael@0:                         SkPoint* qInDevSpace;
michael@0:                         // bounds has to be calculated in device space, but q is
michael@0:                         // in src space when there is perspective.
michael@0:                         if (persp) {
michael@0:                             m.mapPoints(devPts, &q[i], 3);
michael@0:                             bounds.setBounds(devPts, 3);
michael@0:                             qInDevSpace = devPts;
michael@0:                         } else {
michael@0:                             bounds.setBounds(&q[i], 3);
michael@0:                             qInDevSpace = &q[i];
michael@0:                         }
michael@0:                         bounds.outset(SK_Scalar1, SK_Scalar1);
michael@0:                         bounds.roundOut(&ibounds);
michael@0:                         if (SkIRect::Intersects(devClipBounds, ibounds)) {
michael@0:                             int subdiv = num_quad_subdivs(qInDevSpace);
michael@0:                             SkASSERT(subdiv >= -1);
michael@0:                             if (-1 == subdiv) {
michael@0:                                 SkPoint* pts = lines->push_back_n(4);
michael@0:                                 // lines should always be in device coords
michael@0:                                 pts[0] = qInDevSpace[0];
michael@0:                                 pts[1] = qInDevSpace[1];
michael@0:                                 pts[2] = qInDevSpace[1];
michael@0:                                 pts[3] = qInDevSpace[2];
michael@0:                             } else {
michael@0:                                 SkPoint* pts = quads->push_back_n(3);
michael@0:                                 // q is already in src space when there is no
michael@0:                                 // perspective and dev coords otherwise.
michael@0:                                 pts[0] = q[0 + i];
michael@0:                                 pts[1] = q[1 + i];
michael@0:                                 pts[2] = q[2 + i];
michael@0:                                 quadSubdivCnts->push_back() = subdiv;
michael@0:                                 totalQuadCount += 1 << subdiv;
michael@0:                             }
michael@0:                         }
michael@0:                     }
michael@0:                 }
michael@0:                 break;
michael@0:             case SkPath::kClose_Verb:
michael@0:                 break;
michael@0:             case SkPath::kDone_Verb:
michael@0:                 return totalQuadCount;
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: struct LineVertex {
michael@0:     GrPoint fPos;
michael@0:     GrColor fCoverage;
michael@0: };
michael@0: 
michael@0: struct BezierVertex {
michael@0:     GrPoint fPos;
michael@0:     union {
michael@0:         struct {
michael@0:             SkScalar fK;
michael@0:             SkScalar fL;
michael@0:             SkScalar fM;
michael@0:         } fConic;
michael@0:         GrVec   fQuadCoord;
michael@0:         struct {
michael@0:             SkScalar fBogus[4];
michael@0:         };
michael@0:     };
michael@0: };
michael@0: 
michael@0: GR_STATIC_ASSERT(sizeof(BezierVertex) == 3 * sizeof(GrPoint));
michael@0: 
michael@0: void intersect_lines(const SkPoint& ptA, const SkVector& normA,
michael@0:                      const SkPoint& ptB, const SkVector& normB,
michael@0:                      SkPoint* result) {
michael@0: 
michael@0:     SkScalar lineAW = -normA.dot(ptA);
michael@0:     SkScalar lineBW = -normB.dot(ptB);
michael@0: 
michael@0:     SkScalar wInv = SkScalarMul(normA.fX, normB.fY) -
michael@0:         SkScalarMul(normA.fY, normB.fX);
michael@0:     wInv = SkScalarInvert(wInv);
michael@0: 
michael@0:     result->fX = SkScalarMul(normA.fY, lineBW) - SkScalarMul(lineAW, normB.fY);
michael@0:     result->fX = SkScalarMul(result->fX, wInv);
michael@0: 
michael@0:     result->fY = SkScalarMul(lineAW, normB.fX) - SkScalarMul(normA.fX, lineBW);
michael@0:     result->fY = SkScalarMul(result->fY, wInv);
michael@0: }
michael@0: 
michael@0: void set_uv_quad(const SkPoint qpts[3], BezierVertex verts[kVertsPerQuad]) {
michael@0:     // this should be in the src space, not dev coords, when we have perspective
michael@0:     GrPathUtils::QuadUVMatrix DevToUV(qpts);
michael@0:     DevToUV.apply<kVertsPerQuad, sizeof(BezierVertex), sizeof(GrPoint)>(verts);
michael@0: }
michael@0: 
michael@0: void bloat_quad(const SkPoint qpts[3], const SkMatrix* toDevice,
michael@0:                 const SkMatrix* toSrc, BezierVertex verts[kVertsPerQuad],
michael@0:                 SkRect* devBounds) {
michael@0:     SkASSERT(!toDevice == !toSrc);
michael@0:     // original quad is specified by tri a,b,c
michael@0:     SkPoint a = qpts[0];
michael@0:     SkPoint b = qpts[1];
michael@0:     SkPoint c = qpts[2];
michael@0: 
michael@0:     if (toDevice) {
michael@0:         toDevice->mapPoints(&a, 1);
michael@0:         toDevice->mapPoints(&b, 1);
michael@0:         toDevice->mapPoints(&c, 1);
michael@0:     }
michael@0:     // make a new poly where we replace a and c by a 1-pixel wide edges orthog
michael@0:     // to edges ab and bc:
michael@0:     //
michael@0:     //   before       |        after
michael@0:     //                |              b0
michael@0:     //         b      |
michael@0:     //                |
michael@0:     //                |     a0            c0
michael@0:     // a         c    |        a1       c1
michael@0:     //
michael@0:     // edges a0->b0 and b0->c0 are parallel to original edges a->b and b->c,
michael@0:     // respectively.
michael@0:     BezierVertex& a0 = verts[0];
michael@0:     BezierVertex& a1 = verts[1];
michael@0:     BezierVertex& b0 = verts[2];
michael@0:     BezierVertex& c0 = verts[3];
michael@0:     BezierVertex& c1 = verts[4];
michael@0: 
michael@0:     SkVector ab = b;
michael@0:     ab -= a;
michael@0:     SkVector ac = c;
michael@0:     ac -= a;
michael@0:     SkVector cb = b;
michael@0:     cb -= c;
michael@0: 
michael@0:     // We should have already handled degenerates
michael@0:     SkASSERT(ab.length() > 0 && cb.length() > 0);
michael@0: 
michael@0:     ab.normalize();
michael@0:     SkVector abN;
michael@0:     abN.setOrthog(ab, SkVector::kLeft_Side);
michael@0:     if (abN.dot(ac) > 0) {
michael@0:         abN.negate();
michael@0:     }
michael@0: 
michael@0:     cb.normalize();
michael@0:     SkVector cbN;
michael@0:     cbN.setOrthog(cb, SkVector::kLeft_Side);
michael@0:     if (cbN.dot(ac) < 0) {
michael@0:         cbN.negate();
michael@0:     }
michael@0: 
michael@0:     a0.fPos = a;
michael@0:     a0.fPos += abN;
michael@0:     a1.fPos = a;
michael@0:     a1.fPos -= abN;
michael@0: 
michael@0:     c0.fPos = c;
michael@0:     c0.fPos += cbN;
michael@0:     c1.fPos = c;
michael@0:     c1.fPos -= cbN;
michael@0: 
michael@0:     intersect_lines(a0.fPos, abN, c0.fPos, cbN, &b0.fPos);
michael@0:     devBounds->growToInclude(&verts[0].fPos, sizeof(BezierVertex), kVertsPerQuad);
michael@0: 
michael@0:     if (toSrc) {
michael@0:         toSrc->mapPointsWithStride(&verts[0].fPos, sizeof(BezierVertex), kVertsPerQuad);
michael@0:     }
michael@0: }
michael@0: 
michael@0: // Equations based off of Loop-Blinn Quadratic GPU Rendering
michael@0: // Input Parametric:
michael@0: // 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)
michael@0: // Output Implicit:
michael@0: // f(x, y, w) = f(P) = K^2 - LM
michael@0: // K = dot(k, P), L = dot(l, P), M = dot(m, P)
michael@0: // k, l, m are calculated in function GrPathUtils::getConicKLM
michael@0: void set_conic_coeffs(const SkPoint p[3], BezierVertex verts[kVertsPerQuad],
michael@0:                       const SkScalar weight) {
michael@0:     SkScalar klm[9];
michael@0: 
michael@0:     GrPathUtils::getConicKLM(p, weight, klm);
michael@0: 
michael@0:     for (int i = 0; i < kVertsPerQuad; ++i) {
michael@0:         const SkPoint pnt = verts[i].fPos;
michael@0:         verts[i].fConic.fK = pnt.fX * klm[0] + pnt.fY * klm[1] + klm[2];
michael@0:         verts[i].fConic.fL = pnt.fX * klm[3] + pnt.fY * klm[4] + klm[5];
michael@0:         verts[i].fConic.fM = pnt.fX * klm[6] + pnt.fY * klm[7] + klm[8];
michael@0:     }
michael@0: }
michael@0: 
michael@0: void add_conics(const SkPoint p[3],
michael@0:                 const SkScalar weight,
michael@0:                 const SkMatrix* toDevice,
michael@0:                 const SkMatrix* toSrc,
michael@0:                 BezierVertex** vert,
michael@0:                 SkRect* devBounds) {
michael@0:     bloat_quad(p, toDevice, toSrc, *vert, devBounds);
michael@0:     set_conic_coeffs(p, *vert, weight);
michael@0:     *vert += kVertsPerQuad;
michael@0: }
michael@0: 
michael@0: void add_quads(const SkPoint p[3],
michael@0:                int subdiv,
michael@0:                const SkMatrix* toDevice,
michael@0:                const SkMatrix* toSrc,
michael@0:                BezierVertex** vert,
michael@0:                SkRect* devBounds) {
michael@0:     SkASSERT(subdiv >= 0);
michael@0:     if (subdiv) {
michael@0:         SkPoint newP[5];
michael@0:         SkChopQuadAtHalf(p, newP);
michael@0:         add_quads(newP + 0, subdiv-1, toDevice, toSrc, vert, devBounds);
michael@0:         add_quads(newP + 2, subdiv-1, toDevice, toSrc, vert, devBounds);
michael@0:     } else {
michael@0:         bloat_quad(p, toDevice, toSrc, *vert, devBounds);
michael@0:         set_uv_quad(p, *vert);
michael@0:         *vert += kVertsPerQuad;
michael@0:     }
michael@0: }
michael@0: 
michael@0: void add_line(const SkPoint p[2],
michael@0:               const SkMatrix* toSrc,
michael@0:               GrColor coverage,
michael@0:               LineVertex** vert) {
michael@0:     const SkPoint& a = p[0];
michael@0:     const SkPoint& b = p[1];
michael@0: 
michael@0:     SkVector ortho, vec = b;
michael@0:     vec -= a;
michael@0: 
michael@0:     if (vec.setLength(SK_ScalarHalf)) {
michael@0:         // Create a vector orthogonal to 'vec' and of unit length
michael@0:         ortho.fX = 2.0f * vec.fY;
michael@0:         ortho.fY = -2.0f * vec.fX;
michael@0: 
michael@0:         (*vert)[0].fPos = a;
michael@0:         (*vert)[0].fCoverage = coverage;
michael@0:         (*vert)[1].fPos = b;
michael@0:         (*vert)[1].fCoverage = coverage;
michael@0:         (*vert)[2].fPos = a - vec + ortho;
michael@0:         (*vert)[2].fCoverage = 0;
michael@0:         (*vert)[3].fPos = b + vec + ortho;
michael@0:         (*vert)[3].fCoverage = 0;
michael@0:         (*vert)[4].fPos = a - vec - ortho;
michael@0:         (*vert)[4].fCoverage = 0;
michael@0:         (*vert)[5].fPos = b + vec - ortho;
michael@0:         (*vert)[5].fCoverage = 0;
michael@0: 
michael@0:         if (NULL != toSrc) {
michael@0:             toSrc->mapPointsWithStride(&(*vert)->fPos,
michael@0:                                        sizeof(LineVertex),
michael@0:                                        kVertsPerLineSeg);
michael@0:         }
michael@0:     } else {
michael@0:         // just make it degenerate and likely offscreen
michael@0:         for (int i = 0; i < kVertsPerLineSeg; ++i) {
michael@0:             (*vert)[i].fPos.set(SK_ScalarMax, SK_ScalarMax);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     *vert += kVertsPerLineSeg;
michael@0: }
michael@0: 
michael@0: }
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: // position + edge
michael@0: extern const GrVertexAttrib gHairlineBezierAttribs[] = {
michael@0:     {kVec2f_GrVertexAttribType, 0,                  kPosition_GrVertexAttribBinding},
michael@0:     {kVec4f_GrVertexAttribType, sizeof(GrPoint),    kEffect_GrVertexAttribBinding}
michael@0: };
michael@0: 
michael@0: // position + coverage
michael@0: extern const GrVertexAttrib gHairlineLineAttribs[] = {
michael@0:     {kVec2f_GrVertexAttribType,  0,               kPosition_GrVertexAttribBinding},
michael@0:     {kVec4ub_GrVertexAttribType, sizeof(GrPoint), kCoverage_GrVertexAttribBinding},
michael@0: };
michael@0: 
michael@0: };
michael@0: 
michael@0: bool GrAAHairLinePathRenderer::createLineGeom(const SkPath& path,
michael@0:                                               GrDrawTarget* target,
michael@0:                                               const PtArray& lines,
michael@0:                                               int lineCnt,
michael@0:                                               GrDrawTarget::AutoReleaseGeometry* arg,
michael@0:                                               SkRect* devBounds) {
michael@0:     GrDrawState* drawState = target->drawState();
michael@0: 
michael@0:     const SkMatrix& viewM = drawState->getViewMatrix();
michael@0: 
michael@0:     int vertCnt = kVertsPerLineSeg * lineCnt;
michael@0: 
michael@0:     drawState->setVertexAttribs<gHairlineLineAttribs>(SK_ARRAY_COUNT(gHairlineLineAttribs));
michael@0:     SkASSERT(sizeof(LineVertex) == drawState->getVertexSize());
michael@0: 
michael@0:     if (!arg->set(target, vertCnt, 0)) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     LineVertex* verts = reinterpret_cast<LineVertex*>(arg->vertices());
michael@0: 
michael@0:     const SkMatrix* toSrc = NULL;
michael@0:     SkMatrix ivm;
michael@0: 
michael@0:     if (viewM.hasPerspective()) {
michael@0:         if (viewM.invert(&ivm)) {
michael@0:             toSrc = &ivm;
michael@0:         }
michael@0:     }
michael@0:     devBounds->set(lines.begin(), lines.count());
michael@0:     for (int i = 0; i < lineCnt; ++i) {
michael@0:         add_line(&lines[2*i], toSrc, drawState->getCoverageColor(), &verts);
michael@0:     }
michael@0:     // All the verts computed by add_line are within sqrt(1^2 + 0.5^2) of the end points.
michael@0:     static const SkScalar kSqrtOfOneAndAQuarter = 1.118f;
michael@0:     // Add a little extra to account for vector normalization precision.
michael@0:     static const SkScalar kOutset = kSqrtOfOneAndAQuarter + SK_Scalar1 / 20;
michael@0:     devBounds->outset(kOutset, kOutset);
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool GrAAHairLinePathRenderer::createBezierGeom(
michael@0:                                           const SkPath& path,
michael@0:                                           GrDrawTarget* target,
michael@0:                                           const PtArray& quads,
michael@0:                                           int quadCnt,
michael@0:                                           const PtArray& conics,
michael@0:                                           int conicCnt,
michael@0:                                           const IntArray& qSubdivs,
michael@0:                                           const FloatArray& cWeights,
michael@0:                                           GrDrawTarget::AutoReleaseGeometry* arg,
michael@0:                                           SkRect* devBounds) {
michael@0:     GrDrawState* drawState = target->drawState();
michael@0: 
michael@0:     const SkMatrix& viewM = drawState->getViewMatrix();
michael@0: 
michael@0:     int vertCnt = kVertsPerQuad * quadCnt + kVertsPerQuad * conicCnt;
michael@0: 
michael@0:     target->drawState()->setVertexAttribs<gHairlineBezierAttribs>(SK_ARRAY_COUNT(gHairlineBezierAttribs));
michael@0:     SkASSERT(sizeof(BezierVertex) == target->getDrawState().getVertexSize());
michael@0: 
michael@0:     if (!arg->set(target, vertCnt, 0)) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     BezierVertex* verts = reinterpret_cast<BezierVertex*>(arg->vertices());
michael@0: 
michael@0:     const SkMatrix* toDevice = NULL;
michael@0:     const SkMatrix* toSrc = NULL;
michael@0:     SkMatrix ivm;
michael@0: 
michael@0:     if (viewM.hasPerspective()) {
michael@0:         if (viewM.invert(&ivm)) {
michael@0:             toDevice = &viewM;
michael@0:             toSrc = &ivm;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // Seed the dev bounds with some pts known to be inside. Each quad and conic grows the bounding
michael@0:     // box to include its vertices.
michael@0:     SkPoint seedPts[2];
michael@0:     if (quadCnt) {
michael@0:         seedPts[0] = quads[0];
michael@0:         seedPts[1] = quads[2];
michael@0:     } else if (conicCnt) {
michael@0:         seedPts[0] = conics[0];
michael@0:         seedPts[1] = conics[2];
michael@0:     }
michael@0:     if (NULL != toDevice) {
michael@0:         toDevice->mapPoints(seedPts, 2);
michael@0:     }
michael@0:     devBounds->set(seedPts[0], seedPts[1]);
michael@0: 
michael@0:     int unsubdivQuadCnt = quads.count() / 3;
michael@0:     for (int i = 0; i < unsubdivQuadCnt; ++i) {
michael@0:         SkASSERT(qSubdivs[i] >= 0);
michael@0:         add_quads(&quads[3*i], qSubdivs[i], toDevice, toSrc, &verts, devBounds);
michael@0:     }
michael@0: 
michael@0:     // Start Conics
michael@0:     for (int i = 0; i < conicCnt; ++i) {
michael@0:         add_conics(&conics[3*i], cWeights[i], toDevice, toSrc, &verts, devBounds);
michael@0:     }
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool GrAAHairLinePathRenderer::canDrawPath(const SkPath& path,
michael@0:                                            const SkStrokeRec& stroke,
michael@0:                                            const GrDrawTarget* target,
michael@0:                                            bool antiAlias) const {
michael@0:     if (!antiAlias) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     if (!IsStrokeHairlineOrEquivalent(stroke,
michael@0:                                       target->getDrawState().getViewMatrix(),
michael@0:                                       NULL)) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     if (SkPath::kLine_SegmentMask == path.getSegmentMasks() ||
michael@0:         target->caps()->shaderDerivativeSupport()) {
michael@0:         return true;
michael@0:     }
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: template <class VertexType>
michael@0: bool check_bounds(GrDrawState* drawState, const SkRect& devBounds, void* vertices, int vCount)
michael@0: {
michael@0:     SkRect tolDevBounds = devBounds;
michael@0:     // The bounds ought to be tight, but in perspective the below code runs the verts
michael@0:     // through the view matrix to get back to dev coords, which can introduce imprecision.
michael@0:     if (drawState->getViewMatrix().hasPerspective()) {
michael@0:         tolDevBounds.outset(SK_Scalar1 / 1000, SK_Scalar1 / 1000);
michael@0:     } else {
michael@0:         // Non-persp matrices cause this path renderer to draw in device space.
michael@0:         SkASSERT(drawState->getViewMatrix().isIdentity());
michael@0:     }
michael@0:     SkRect actualBounds;
michael@0: 
michael@0:     VertexType* verts = reinterpret_cast<VertexType*>(vertices);
michael@0:     bool first = true;
michael@0:     for (int i = 0; i < vCount; ++i) {
michael@0:         SkPoint pos = verts[i].fPos;
michael@0:         // This is a hack to workaround the fact that we move some degenerate segments offscreen.
michael@0:         if (SK_ScalarMax == pos.fX) {
michael@0:             continue;
michael@0:         }
michael@0:         drawState->getViewMatrix().mapPoints(&pos, 1);
michael@0:         if (first) {
michael@0:             actualBounds.set(pos.fX, pos.fY, pos.fX, pos.fY);
michael@0:             first = false;
michael@0:         } else {
michael@0:             actualBounds.growToInclude(pos.fX, pos.fY);
michael@0:         }
michael@0:     }
michael@0:     if (!first) {
michael@0:         return tolDevBounds.contains(actualBounds);
michael@0:     }
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool GrAAHairLinePathRenderer::onDrawPath(const SkPath& path,
michael@0:                                           const SkStrokeRec& stroke,
michael@0:                                           GrDrawTarget* target,
michael@0:                                           bool antiAlias) {
michael@0:     GrDrawState* drawState = target->drawState();
michael@0: 
michael@0:     SkScalar hairlineCoverage;
michael@0:     if (IsStrokeHairlineOrEquivalent(stroke,
michael@0:                                      target->getDrawState().getViewMatrix(),
michael@0:                                      &hairlineCoverage)) {
michael@0:         uint8_t newCoverage = SkScalarRoundToInt(hairlineCoverage *
michael@0:                                                  target->getDrawState().getCoverage());
michael@0:         target->drawState()->setCoverage(newCoverage);
michael@0:     }
michael@0: 
michael@0:     SkIRect devClipBounds;
michael@0:     target->getClip()->getConservativeBounds(drawState->getRenderTarget(), &devClipBounds);
michael@0: 
michael@0:     int lineCnt;
michael@0:     int quadCnt;
michael@0:     int conicCnt;
michael@0:     PREALLOC_PTARRAY(128) lines;
michael@0:     PREALLOC_PTARRAY(128) quads;
michael@0:     PREALLOC_PTARRAY(128) conics;
michael@0:     IntArray qSubdivs;
michael@0:     FloatArray cWeights;
michael@0:     quadCnt = generate_lines_and_quads(path, drawState->getViewMatrix(), devClipBounds,
michael@0:                                        &lines, &quads, &conics, &qSubdivs, &cWeights);
michael@0:     lineCnt = lines.count() / 2;
michael@0:     conicCnt = conics.count() / 3;
michael@0: 
michael@0:     // do lines first
michael@0:     if (lineCnt) {
michael@0:         GrDrawTarget::AutoReleaseGeometry arg;
michael@0:         SkRect devBounds;
michael@0: 
michael@0:         if (!this->createLineGeom(path,
michael@0:                                   target,
michael@0:                                   lines,
michael@0:                                   lineCnt,
michael@0:                                   &arg,
michael@0:                                   &devBounds)) {
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         GrDrawTarget::AutoStateRestore asr;
michael@0: 
michael@0:         // createLineGeom transforms the geometry to device space when the matrix does not have
michael@0:         // perspective.
michael@0:         if (target->getDrawState().getViewMatrix().hasPerspective()) {
michael@0:             asr.set(target, GrDrawTarget::kPreserve_ASRInit);
michael@0:         } else if (!asr.setIdentity(target, GrDrawTarget::kPreserve_ASRInit)) {
michael@0:             return false;
michael@0:         }
michael@0:         GrDrawState* drawState = target->drawState();
michael@0: 
michael@0:         // Check devBounds
michael@0:         SkASSERT(check_bounds<LineVertex>(drawState, devBounds, arg.vertices(),
michael@0:                                           kVertsPerLineSeg * lineCnt));
michael@0: 
michael@0:         {
michael@0:             GrDrawState::AutoRestoreEffects are(drawState);
michael@0:             target->setIndexSourceToBuffer(fLinesIndexBuffer);
michael@0:             int lines = 0;
michael@0:             while (lines < lineCnt) {
michael@0:                 int n = GrMin(lineCnt - lines, kNumLineSegsInIdxBuffer);
michael@0:                 target->drawIndexed(kTriangles_GrPrimitiveType,
michael@0:                                     kVertsPerLineSeg*lines,     // startV
michael@0:                                     0,                          // startI
michael@0:                                     kVertsPerLineSeg*n,         // vCount
michael@0:                                     kIdxsPerLineSeg*n,          // iCount
michael@0:                                     &devBounds);
michael@0:                 lines += n;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // then quadratics/conics
michael@0:     if (quadCnt || conicCnt) {
michael@0:         GrDrawTarget::AutoReleaseGeometry arg;
michael@0:         SkRect devBounds;
michael@0: 
michael@0:         if (!this->createBezierGeom(path,
michael@0:                                     target,
michael@0:                                     quads,
michael@0:                                     quadCnt,
michael@0:                                     conics,
michael@0:                                     conicCnt,
michael@0:                                     qSubdivs,
michael@0:                                     cWeights,
michael@0:                                     &arg,
michael@0:                                     &devBounds)) {
michael@0:             return false;
michael@0:         }
michael@0: 
michael@0:         GrDrawTarget::AutoStateRestore asr;
michael@0: 
michael@0:         // createGeom transforms the geometry to device space when the matrix does not have
michael@0:         // perspective.
michael@0:         if (target->getDrawState().getViewMatrix().hasPerspective()) {
michael@0:             asr.set(target, GrDrawTarget::kPreserve_ASRInit);
michael@0:         } else if (!asr.setIdentity(target, GrDrawTarget::kPreserve_ASRInit)) {
michael@0:             return false;
michael@0:         }
michael@0:         GrDrawState* drawState = target->drawState();
michael@0: 
michael@0:         static const int kEdgeAttrIndex = 1;
michael@0: 
michael@0:         // Check devBounds
michael@0:         SkASSERT(check_bounds<BezierVertex>(drawState, devBounds, arg.vertices(),
michael@0:                                             kVertsPerQuad * quadCnt + kVertsPerQuad * conicCnt));
michael@0: 
michael@0:         if (quadCnt > 0) {
michael@0:             GrEffectRef* hairQuadEffect = GrQuadEffect::Create(kHairlineAA_GrEffectEdgeType,
michael@0:                                                                *target->caps());
michael@0:             SkASSERT(NULL != hairQuadEffect);
michael@0:             GrDrawState::AutoRestoreEffects are(drawState);
michael@0:             target->setIndexSourceToBuffer(fQuadsIndexBuffer);
michael@0:             drawState->addCoverageEffect(hairQuadEffect, kEdgeAttrIndex)->unref();
michael@0:             int quads = 0;
michael@0:             while (quads < quadCnt) {
michael@0:                 int n = GrMin(quadCnt - quads, kNumQuadsInIdxBuffer);
michael@0:                 target->drawIndexed(kTriangles_GrPrimitiveType,
michael@0:                                     kVertsPerQuad*quads,               // startV
michael@0:                                     0,                                 // startI
michael@0:                                     kVertsPerQuad*n,                   // vCount
michael@0:                                     kIdxsPerQuad*n,                    // iCount
michael@0:                                     &devBounds);
michael@0:                 quads += n;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         if (conicCnt > 0) {
michael@0:             GrDrawState::AutoRestoreEffects are(drawState);
michael@0:             GrEffectRef* hairConicEffect = GrConicEffect::Create(kHairlineAA_GrEffectEdgeType,
michael@0:                                                                  *target->caps());
michael@0:             SkASSERT(NULL != hairConicEffect);
michael@0:             drawState->addCoverageEffect(hairConicEffect, 1, 2)->unref();
michael@0:             int conics = 0;
michael@0:             while (conics < conicCnt) {
michael@0:                 int n = GrMin(conicCnt - conics, kNumQuadsInIdxBuffer);
michael@0:                 target->drawIndexed(kTriangles_GrPrimitiveType,
michael@0:                                     kVertsPerQuad*(quadCnt + conics),  // startV
michael@0:                                     0,                                 // startI
michael@0:                                     kVertsPerQuad*n,                   // vCount
michael@0:                                     kIdxsPerQuad*n,                    // iCount
michael@0:                                     &devBounds);
michael@0:                 conics += n;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     target->resetIndexSource();
michael@0: 
michael@0:     return true;
michael@0: }