| |
| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "GrAAConvexPathRenderer.h" |
| |
| #include "GrContext.h" |
| #include "GrDrawState.h" |
| #include "GrDrawTargetCaps.h" |
| #include "GrProcessor.h" |
| #include "GrPathUtils.h" |
| #include "GrTBackendProcessorFactory.h" |
| #include "SkString.h" |
| #include "SkStrokeRec.h" |
| #include "SkTraceEvent.h" |
| |
| #include "gl/builders/GrGLFullProgramBuilder.h" |
| #include "gl/GrGLProcessor.h" |
| #include "gl/GrGLSL.h" |
| #include "gl/GrGLGeometryProcessor.h" |
| |
| #include "GrGeometryProcessor.h" |
| |
| GrAAConvexPathRenderer::GrAAConvexPathRenderer() { |
| } |
| |
| struct Segment { |
| enum { |
| // These enum values are assumed in member functions below. |
| kLine = 0, |
| kQuad = 1, |
| } fType; |
| |
| // line uses one pt, quad uses 2 pts |
| SkPoint fPts[2]; |
| // normal to edge ending at each pt |
| SkVector fNorms[2]; |
| // is the corner where the previous segment meets this segment |
| // sharp. If so, fMid is a normalized bisector facing outward. |
| SkVector fMid; |
| |
| int countPoints() { |
| GR_STATIC_ASSERT(0 == kLine && 1 == kQuad); |
| return fType + 1; |
| } |
| const SkPoint& endPt() const { |
| GR_STATIC_ASSERT(0 == kLine && 1 == kQuad); |
| return fPts[fType]; |
| }; |
| const SkPoint& endNorm() const { |
| GR_STATIC_ASSERT(0 == kLine && 1 == kQuad); |
| return fNorms[fType]; |
| }; |
| }; |
| |
| typedef SkTArray<Segment, true> SegmentArray; |
| |
| static void center_of_mass(const SegmentArray& segments, SkPoint* c) { |
| SkScalar area = 0; |
| SkPoint center = {0, 0}; |
| int count = segments.count(); |
| SkPoint p0 = {0, 0}; |
| if (count > 2) { |
| // We translate the polygon so that the first point is at the origin. |
| // This avoids some precision issues with small area polygons far away |
| // from the origin. |
| p0 = segments[0].endPt(); |
| SkPoint pi; |
| SkPoint pj; |
| // the first and last iteration of the below loop would compute |
| // zeros since the starting / ending point is (0,0). So instead we start |
| // at i=1 and make the last iteration i=count-2. |
| pj = segments[1].endPt() - p0; |
| for (int i = 1; i < count - 1; ++i) { |
| pi = pj; |
| const SkPoint pj = segments[i + 1].endPt() - p0; |
| |
| SkScalar t = SkScalarMul(pi.fX, pj.fY) - SkScalarMul(pj.fX, pi.fY); |
| area += t; |
| center.fX += (pi.fX + pj.fX) * t; |
| center.fY += (pi.fY + pj.fY) * t; |
| |
| } |
| } |
| // If the poly has no area then we instead return the average of |
| // its points. |
| if (SkScalarNearlyZero(area)) { |
| SkPoint avg; |
| avg.set(0, 0); |
| for (int i = 0; i < count; ++i) { |
| const SkPoint& pt = segments[i].endPt(); |
| avg.fX += pt.fX; |
| avg.fY += pt.fY; |
| } |
| SkScalar denom = SK_Scalar1 / count; |
| avg.scale(denom); |
| *c = avg; |
| } else { |
| area *= 3; |
| area = SkScalarDiv(SK_Scalar1, area); |
| center.fX = SkScalarMul(center.fX, area); |
| center.fY = SkScalarMul(center.fY, area); |
| // undo the translate of p0 to the origin. |
| *c = center + p0; |
| } |
| SkASSERT(!SkScalarIsNaN(c->fX) && !SkScalarIsNaN(c->fY)); |
| } |
| |
| static void compute_vectors(SegmentArray* segments, |
| SkPoint* fanPt, |
| SkPath::Direction dir, |
| int* vCount, |
| int* iCount) { |
| center_of_mass(*segments, fanPt); |
| int count = segments->count(); |
| |
| // Make the normals point towards the outside |
| SkPoint::Side normSide; |
| if (dir == SkPath::kCCW_Direction) { |
| normSide = SkPoint::kRight_Side; |
| } else { |
| normSide = SkPoint::kLeft_Side; |
| } |
| |
| *vCount = 0; |
| *iCount = 0; |
| // compute normals at all points |
| for (int a = 0; a < count; ++a) { |
| Segment& sega = (*segments)[a]; |
| int b = (a + 1) % count; |
| Segment& segb = (*segments)[b]; |
| |
| const SkPoint* prevPt = &sega.endPt(); |
| int n = segb.countPoints(); |
| for (int p = 0; p < n; ++p) { |
| segb.fNorms[p] = segb.fPts[p] - *prevPt; |
| segb.fNorms[p].normalize(); |
| segb.fNorms[p].setOrthog(segb.fNorms[p], normSide); |
| prevPt = &segb.fPts[p]; |
| } |
| if (Segment::kLine == segb.fType) { |
| *vCount += 5; |
| *iCount += 9; |
| } else { |
| *vCount += 6; |
| *iCount += 12; |
| } |
| } |
| |
| // compute mid-vectors where segments meet. TODO: Detect shallow corners |
| // and leave out the wedges and close gaps by stitching segments together. |
| for (int a = 0; a < count; ++a) { |
| const Segment& sega = (*segments)[a]; |
| int b = (a + 1) % count; |
| Segment& segb = (*segments)[b]; |
| segb.fMid = segb.fNorms[0] + sega.endNorm(); |
| segb.fMid.normalize(); |
| // corner wedges |
| *vCount += 4; |
| *iCount += 6; |
| } |
| } |
| |
| struct DegenerateTestData { |
| DegenerateTestData() { fStage = kInitial; } |
| bool isDegenerate() const { return kNonDegenerate != fStage; } |
| enum { |
| kInitial, |
| kPoint, |
| kLine, |
| kNonDegenerate |
| } fStage; |
| SkPoint fFirstPoint; |
| SkVector fLineNormal; |
| SkScalar fLineC; |
| }; |
| |
| static const SkScalar kClose = (SK_Scalar1 / 16); |
| static const SkScalar kCloseSqd = SkScalarMul(kClose, kClose); |
| |
| static void update_degenerate_test(DegenerateTestData* data, const SkPoint& pt) { |
| switch (data->fStage) { |
| case DegenerateTestData::kInitial: |
| data->fFirstPoint = pt; |
| data->fStage = DegenerateTestData::kPoint; |
| break; |
| case DegenerateTestData::kPoint: |
| if (pt.distanceToSqd(data->fFirstPoint) > kCloseSqd) { |
| data->fLineNormal = pt - data->fFirstPoint; |
| data->fLineNormal.normalize(); |
| data->fLineNormal.setOrthog(data->fLineNormal); |
| data->fLineC = -data->fLineNormal.dot(data->fFirstPoint); |
| data->fStage = DegenerateTestData::kLine; |
| } |
| break; |
| case DegenerateTestData::kLine: |
| if (SkScalarAbs(data->fLineNormal.dot(pt) + data->fLineC) > kClose) { |
| data->fStage = DegenerateTestData::kNonDegenerate; |
| } |
| case DegenerateTestData::kNonDegenerate: |
| break; |
| default: |
| SkFAIL("Unexpected degenerate test stage."); |
| } |
| } |
| |
| static inline bool get_direction(const SkPath& path, const SkMatrix& m, SkPath::Direction* dir) { |
| if (!path.cheapComputeDirection(dir)) { |
| return false; |
| } |
| // check whether m reverses the orientation |
| SkASSERT(!m.hasPerspective()); |
| SkScalar det2x2 = SkScalarMul(m.get(SkMatrix::kMScaleX), m.get(SkMatrix::kMScaleY)) - |
| SkScalarMul(m.get(SkMatrix::kMSkewX), m.get(SkMatrix::kMSkewY)); |
| if (det2x2 < 0) { |
| *dir = SkPath::OppositeDirection(*dir); |
| } |
| return true; |
| } |
| |
| static inline void add_line_to_segment(const SkPoint& pt, |
| SegmentArray* segments, |
| SkRect* devBounds) { |
| segments->push_back(); |
| segments->back().fType = Segment::kLine; |
| segments->back().fPts[0] = pt; |
| devBounds->growToInclude(pt.fX, pt.fY); |
| } |
| |
| #ifdef SK_DEBUG |
| static inline bool contains_inclusive(const SkRect& rect, const SkPoint& p) { |
| return p.fX >= rect.fLeft && p.fX <= rect.fRight && p.fY >= rect.fTop && p.fY <= rect.fBottom; |
| } |
| #endif |
| |
| static inline void add_quad_segment(const SkPoint pts[3], |
| SegmentArray* segments, |
| SkRect* devBounds) { |
| if (pts[0].distanceToSqd(pts[1]) < kCloseSqd || pts[1].distanceToSqd(pts[2]) < kCloseSqd) { |
| if (pts[0] != pts[2]) { |
| add_line_to_segment(pts[2], segments, devBounds); |
| } |
| } else { |
| segments->push_back(); |
| segments->back().fType = Segment::kQuad; |
| segments->back().fPts[0] = pts[1]; |
| segments->back().fPts[1] = pts[2]; |
| devBounds->growToInclude(pts + 1, 2); |
| } |
| } |
| |
| static inline void add_cubic_segments(const SkPoint pts[4], |
| SkPath::Direction dir, |
| SegmentArray* segments, |
| SkRect* devBounds) { |
| SkSTArray<15, SkPoint, true> quads; |
| GrPathUtils::convertCubicToQuads(pts, SK_Scalar1, true, dir, &quads); |
| int count = quads.count(); |
| for (int q = 0; q < count; q += 3) { |
| add_quad_segment(&quads[q], segments, devBounds); |
| } |
| } |
| |
| static bool get_segments(const SkPath& path, |
| const SkMatrix& m, |
| SegmentArray* segments, |
| SkPoint* fanPt, |
| int* vCount, |
| int* iCount, |
| SkRect* devBounds) { |
| SkPath::Iter iter(path, true); |
| // This renderer over-emphasizes very thin path regions. We use the distance |
| // to the path from the sample to compute coverage. Every pixel intersected |
| // by the path will be hit and the maximum distance is sqrt(2)/2. We don't |
| // notice that the sample may be close to a very thin area of the path and |
| // thus should be very light. This is particularly egregious for degenerate |
| // line paths. We detect paths that are very close to a line (zero area) and |
| // draw nothing. |
| DegenerateTestData degenerateData; |
| SkPath::Direction dir; |
| // get_direction can fail for some degenerate paths. |
| if (!get_direction(path, m, &dir)) { |
| return false; |
| } |
| |
| for (;;) { |
| SkPoint pts[4]; |
| SkPath::Verb verb = iter.next(pts); |
| switch (verb) { |
| case SkPath::kMove_Verb: |
| m.mapPoints(pts, 1); |
| update_degenerate_test(°enerateData, pts[0]); |
| devBounds->set(pts->fX, pts->fY, pts->fX, pts->fY); |
| break; |
| case SkPath::kLine_Verb: { |
| m.mapPoints(&pts[1], 1); |
| update_degenerate_test(°enerateData, pts[1]); |
| add_line_to_segment(pts[1], segments, devBounds); |
| break; |
| } |
| case SkPath::kQuad_Verb: |
| m.mapPoints(pts, 3); |
| update_degenerate_test(°enerateData, pts[1]); |
| update_degenerate_test(°enerateData, pts[2]); |
| add_quad_segment(pts, segments, devBounds); |
| break; |
| case SkPath::kCubic_Verb: { |
| m.mapPoints(pts, 4); |
| update_degenerate_test(°enerateData, pts[1]); |
| update_degenerate_test(°enerateData, pts[2]); |
| update_degenerate_test(°enerateData, pts[3]); |
| add_cubic_segments(pts, dir, segments, devBounds); |
| break; |
| }; |
| case SkPath::kDone_Verb: |
| if (degenerateData.isDegenerate()) { |
| return false; |
| } else { |
| compute_vectors(segments, fanPt, dir, vCount, iCount); |
| return true; |
| } |
| default: |
| break; |
| } |
| } |
| } |
| |
| struct QuadVertex { |
| SkPoint fPos; |
| SkPoint fUV; |
| SkScalar fD0; |
| SkScalar fD1; |
| }; |
| |
| struct Draw { |
| Draw() : fVertexCnt(0), fIndexCnt(0) {} |
| int fVertexCnt; |
| int fIndexCnt; |
| }; |
| |
| typedef SkTArray<Draw, true> DrawArray; |
| |
| static void create_vertices(const SegmentArray& segments, |
| const SkPoint& fanPt, |
| DrawArray* draws, |
| QuadVertex* verts, |
| uint16_t* idxs) { |
| Draw* draw = &draws->push_back(); |
| // alias just to make vert/index assignments easier to read. |
| int* v = &draw->fVertexCnt; |
| int* i = &draw->fIndexCnt; |
| |
| int count = segments.count(); |
| for (int a = 0; a < count; ++a) { |
| const Segment& sega = segments[a]; |
| int b = (a + 1) % count; |
| const Segment& segb = segments[b]; |
| |
| // Check whether adding the verts for this segment to the current draw would cause index |
| // values to overflow. |
| int vCount = 4; |
| if (Segment::kLine == segb.fType) { |
| vCount += 5; |
| } else { |
| vCount += 6; |
| } |
| if (draw->fVertexCnt + vCount > (1 << 16)) { |
| verts += *v; |
| idxs += *i; |
| draw = &draws->push_back(); |
| v = &draw->fVertexCnt; |
| i = &draw->fIndexCnt; |
| } |
| |
| // FIXME: These tris are inset in the 1 unit arc around the corner |
| verts[*v + 0].fPos = sega.endPt(); |
| verts[*v + 1].fPos = verts[*v + 0].fPos + sega.endNorm(); |
| verts[*v + 2].fPos = verts[*v + 0].fPos + segb.fMid; |
| verts[*v + 3].fPos = verts[*v + 0].fPos + segb.fNorms[0]; |
| verts[*v + 0].fUV.set(0,0); |
| verts[*v + 1].fUV.set(0,-SK_Scalar1); |
| verts[*v + 2].fUV.set(0,-SK_Scalar1); |
| verts[*v + 3].fUV.set(0,-SK_Scalar1); |
| verts[*v + 0].fD0 = verts[*v + 0].fD1 = -SK_Scalar1; |
| verts[*v + 1].fD0 = verts[*v + 1].fD1 = -SK_Scalar1; |
| verts[*v + 2].fD0 = verts[*v + 2].fD1 = -SK_Scalar1; |
| verts[*v + 3].fD0 = verts[*v + 3].fD1 = -SK_Scalar1; |
| |
| idxs[*i + 0] = *v + 0; |
| idxs[*i + 1] = *v + 2; |
| idxs[*i + 2] = *v + 1; |
| idxs[*i + 3] = *v + 0; |
| idxs[*i + 4] = *v + 3; |
| idxs[*i + 5] = *v + 2; |
| |
| *v += 4; |
| *i += 6; |
| |
| if (Segment::kLine == segb.fType) { |
| verts[*v + 0].fPos = fanPt; |
| verts[*v + 1].fPos = sega.endPt(); |
| verts[*v + 2].fPos = segb.fPts[0]; |
| |
| verts[*v + 3].fPos = verts[*v + 1].fPos + segb.fNorms[0]; |
| verts[*v + 4].fPos = verts[*v + 2].fPos + segb.fNorms[0]; |
| |
| // we draw the line edge as a degenerate quad (u is 0, v is the |
| // signed distance to the edge) |
| SkScalar dist = fanPt.distanceToLineBetween(verts[*v + 1].fPos, |
| verts[*v + 2].fPos); |
| verts[*v + 0].fUV.set(0, dist); |
| verts[*v + 1].fUV.set(0, 0); |
| verts[*v + 2].fUV.set(0, 0); |
| verts[*v + 3].fUV.set(0, -SK_Scalar1); |
| verts[*v + 4].fUV.set(0, -SK_Scalar1); |
| |
| verts[*v + 0].fD0 = verts[*v + 0].fD1 = -SK_Scalar1; |
| verts[*v + 1].fD0 = verts[*v + 1].fD1 = -SK_Scalar1; |
| verts[*v + 2].fD0 = verts[*v + 2].fD1 = -SK_Scalar1; |
| verts[*v + 3].fD0 = verts[*v + 3].fD1 = -SK_Scalar1; |
| verts[*v + 4].fD0 = verts[*v + 4].fD1 = -SK_Scalar1; |
| |
| idxs[*i + 0] = *v + 0; |
| idxs[*i + 1] = *v + 2; |
| idxs[*i + 2] = *v + 1; |
| |
| idxs[*i + 3] = *v + 3; |
| idxs[*i + 4] = *v + 1; |
| idxs[*i + 5] = *v + 2; |
| |
| idxs[*i + 6] = *v + 4; |
| idxs[*i + 7] = *v + 3; |
| idxs[*i + 8] = *v + 2; |
| |
| *v += 5; |
| *i += 9; |
| } else { |
| SkPoint qpts[] = {sega.endPt(), segb.fPts[0], segb.fPts[1]}; |
| |
| SkVector midVec = segb.fNorms[0] + segb.fNorms[1]; |
| midVec.normalize(); |
| |
| verts[*v + 0].fPos = fanPt; |
| verts[*v + 1].fPos = qpts[0]; |
| verts[*v + 2].fPos = qpts[2]; |
| verts[*v + 3].fPos = qpts[0] + segb.fNorms[0]; |
| verts[*v + 4].fPos = qpts[2] + segb.fNorms[1]; |
| verts[*v + 5].fPos = qpts[1] + midVec; |
| |
| SkScalar c = segb.fNorms[0].dot(qpts[0]); |
| verts[*v + 0].fD0 = -segb.fNorms[0].dot(fanPt) + c; |
| verts[*v + 1].fD0 = 0.f; |
| verts[*v + 2].fD0 = -segb.fNorms[0].dot(qpts[2]) + c; |
| verts[*v + 3].fD0 = -SK_ScalarMax/100; |
| verts[*v + 4].fD0 = -SK_ScalarMax/100; |
| verts[*v + 5].fD0 = -SK_ScalarMax/100; |
| |
| c = segb.fNorms[1].dot(qpts[2]); |
| verts[*v + 0].fD1 = -segb.fNorms[1].dot(fanPt) + c; |
| verts[*v + 1].fD1 = -segb.fNorms[1].dot(qpts[0]) + c; |
| verts[*v + 2].fD1 = 0.f; |
| verts[*v + 3].fD1 = -SK_ScalarMax/100; |
| verts[*v + 4].fD1 = -SK_ScalarMax/100; |
| verts[*v + 5].fD1 = -SK_ScalarMax/100; |
| |
| GrPathUtils::QuadUVMatrix toUV(qpts); |
| toUV.apply<6, sizeof(QuadVertex), sizeof(SkPoint)>(verts + *v); |
| |
| idxs[*i + 0] = *v + 3; |
| idxs[*i + 1] = *v + 1; |
| idxs[*i + 2] = *v + 2; |
| idxs[*i + 3] = *v + 4; |
| idxs[*i + 4] = *v + 3; |
| idxs[*i + 5] = *v + 2; |
| |
| idxs[*i + 6] = *v + 5; |
| idxs[*i + 7] = *v + 3; |
| idxs[*i + 8] = *v + 4; |
| |
| idxs[*i + 9] = *v + 0; |
| idxs[*i + 10] = *v + 2; |
| idxs[*i + 11] = *v + 1; |
| |
| *v += 6; |
| *i += 12; |
| } |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| /* |
| * Quadratic specified by 0=u^2-v canonical coords. u and v are the first |
| * two components of the vertex attribute. Coverage is based on signed |
| * distance with negative being inside, positive outside. The edge is specified in |
| * window space (y-down). If either the third or fourth component of the interpolated |
| * vertex coord is > 0 then the pixel is considered outside the edge. This is used to |
| * attempt to trim to a portion of the infinite quad. |
| * Requires shader derivative instruction support. |
| */ |
| |
| class QuadEdgeEffect : public GrGeometryProcessor { |
| public: |
| |
| static GrGeometryProcessor* Create() { |
| GR_CREATE_STATIC_GEOMETRY_PROCESSOR(gQuadEdgeEffect, QuadEdgeEffect, ()); |
| gQuadEdgeEffect->ref(); |
| return gQuadEdgeEffect; |
| } |
| |
| virtual ~QuadEdgeEffect() {} |
| |
| static const char* Name() { return "QuadEdge"; } |
| |
| virtual void getConstantColorComponents(GrColor* color, |
| uint32_t* validFlags) const SK_OVERRIDE { |
| *validFlags = 0; |
| } |
| |
| const GrShaderVar& inQuadEdge() const { return fInQuadEdge; } |
| |
| virtual const GrBackendGeometryProcessorFactory& getFactory() const SK_OVERRIDE { |
| return GrTBackendGeometryProcessorFactory<QuadEdgeEffect>::getInstance(); |
| } |
| |
| class GLProcessor : public GrGLGeometryProcessor { |
| public: |
| GLProcessor(const GrBackendProcessorFactory& factory, const GrProcessor&) |
| : INHERITED (factory) {} |
| |
| virtual void emitCode(GrGLFullProgramBuilder* builder, |
| const GrGeometryProcessor& geometryProcessor, |
| const GrProcessorKey& key, |
| const char* outputColor, |
| const char* inputColor, |
| const TransformedCoordsArray&, |
| const TextureSamplerArray& samplers) SK_OVERRIDE { |
| const char *vsName, *fsName; |
| builder->addVarying(kVec4f_GrSLType, "QuadEdge", &vsName, &fsName); |
| |
| GrGLProcessorFragmentShaderBuilder* fsBuilder = builder->getFragmentShaderBuilder(); |
| |
| SkAssertResult(fsBuilder->enableFeature( |
| GrGLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature)); |
| fsBuilder->codeAppendf("\t\tfloat edgeAlpha;\n"); |
| |
| // keep the derivative instructions outside the conditional |
| fsBuilder->codeAppendf("\t\tvec2 duvdx = dFdx(%s.xy);\n", fsName); |
| fsBuilder->codeAppendf("\t\tvec2 duvdy = dFdy(%s.xy);\n", fsName); |
| fsBuilder->codeAppendf("\t\tif (%s.z > 0.0 && %s.w > 0.0) {\n", fsName, fsName); |
| // today we know z and w are in device space. We could use derivatives |
| fsBuilder->codeAppendf("\t\t\tedgeAlpha = min(min(%s.z, %s.w) + 0.5, 1.0);\n", fsName, |
| fsName); |
| fsBuilder->codeAppendf ("\t\t} else {\n"); |
| fsBuilder->codeAppendf("\t\t\tvec2 gF = vec2(2.0*%s.x*duvdx.x - duvdx.y,\n" |
| "\t\t\t 2.0*%s.x*duvdy.x - duvdy.y);\n", |
| fsName, fsName); |
| fsBuilder->codeAppendf("\t\t\tedgeAlpha = (%s.x*%s.x - %s.y);\n", fsName, fsName, |
| fsName); |
| fsBuilder->codeAppendf("\t\t\tedgeAlpha = " |
| "clamp(0.5 - edgeAlpha / length(gF), 0.0, 1.0);\n\t\t}\n"); |
| |
| |
| fsBuilder->codeAppendf("\t%s = %s;\n", outputColor, |
| (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str()); |
| |
| const GrShaderVar& inQuadEdge = geometryProcessor.cast<QuadEdgeEffect>().inQuadEdge(); |
| GrGLVertexShaderBuilder* vsBuilder = builder->getVertexShaderBuilder(); |
| vsBuilder->codeAppendf("\t%s = %s;\n", vsName, inQuadEdge.c_str()); |
| } |
| |
| static inline void GenKey(const GrProcessor&, const GrGLCaps&, GrProcessorKeyBuilder*) {} |
| |
| virtual void setData(const GrGLProgramDataManager&, const GrProcessor&) SK_OVERRIDE {} |
| |
| private: |
| typedef GrGLGeometryProcessor INHERITED; |
| }; |
| |
| private: |
| QuadEdgeEffect() |
| : fInQuadEdge(this->addVertexAttrib(GrShaderVar("inQuadEdge", |
| kVec4f_GrSLType, |
| GrShaderVar::kAttribute_TypeModifier))) { |
| } |
| |
| virtual bool onIsEqual(const GrProcessor& other) const SK_OVERRIDE { |
| return true; |
| } |
| |
| const GrShaderVar& fInQuadEdge; |
| |
| GR_DECLARE_GEOMETRY_PROCESSOR_TEST; |
| |
| typedef GrFragmentProcessor INHERITED; |
| }; |
| |
| GR_DEFINE_GEOMETRY_PROCESSOR_TEST(QuadEdgeEffect); |
| |
| GrGeometryProcessor* QuadEdgeEffect::TestCreate(SkRandom* random, |
| GrContext*, |
| const GrDrawTargetCaps& caps, |
| GrTexture*[]) { |
| // Doesn't work without derivative instructions. |
| return caps.shaderDerivativeSupport() ? QuadEdgeEffect::Create() : NULL; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| bool GrAAConvexPathRenderer::canDrawPath(const SkPath& path, |
| const SkStrokeRec& stroke, |
| const GrDrawTarget* target, |
| bool antiAlias) const { |
| return (target->caps()->shaderDerivativeSupport() && antiAlias && |
| stroke.isFillStyle() && !path.isInverseFillType() && path.isConvex()); |
| } |
| |
| namespace { |
| |
| // position + edge |
| extern const GrVertexAttrib gPathAttribs[] = { |
| {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}, |
| {kVec4f_GrVertexAttribType, sizeof(SkPoint), kGeometryProcessor_GrVertexAttribBinding} |
| }; |
| |
| }; |
| |
| bool GrAAConvexPathRenderer::onDrawPath(const SkPath& origPath, |
| const SkStrokeRec&, |
| GrDrawTarget* target, |
| bool antiAlias) { |
| |
| const SkPath* path = &origPath; |
| if (path->isEmpty()) { |
| return true; |
| } |
| |
| SkMatrix viewMatrix = target->getDrawState().getViewMatrix(); |
| GrDrawTarget::AutoStateRestore asr; |
| if (!asr.setIdentity(target, GrDrawTarget::kPreserve_ASRInit)) { |
| return false; |
| } |
| GrDrawState* drawState = target->drawState(); |
| |
| // We use the fact that SkPath::transform path does subdivision based on |
| // perspective. Otherwise, we apply the view matrix when copying to the |
| // segment representation. |
| SkPath tmpPath; |
| if (viewMatrix.hasPerspective()) { |
| origPath.transform(viewMatrix, &tmpPath); |
| path = &tmpPath; |
| viewMatrix = SkMatrix::I(); |
| } |
| |
| QuadVertex *verts; |
| uint16_t* idxs; |
| |
| int vCount; |
| int iCount; |
| enum { |
| kPreallocSegmentCnt = 512 / sizeof(Segment), |
| kPreallocDrawCnt = 4, |
| }; |
| SkSTArray<kPreallocSegmentCnt, Segment, true> segments; |
| SkPoint fanPt; |
| |
| // We can't simply use the path bounds because we may degenerate cubics to quads which produces |
| // new control points outside the original convex hull. |
| SkRect devBounds; |
| if (!get_segments(*path, viewMatrix, &segments, &fanPt, &vCount, &iCount, &devBounds)) { |
| return false; |
| } |
| |
| // Our computed verts should all be within one pixel of the segment control points. |
| devBounds.outset(SK_Scalar1, SK_Scalar1); |
| |
| drawState->setVertexAttribs<gPathAttribs>(SK_ARRAY_COUNT(gPathAttribs), sizeof(QuadVertex)); |
| |
| GrGeometryProcessor* quadProcessor = QuadEdgeEffect::Create(); |
| drawState->setGeometryProcessor(quadProcessor)->unref(); |
| |
| GrDrawTarget::AutoReleaseGeometry arg(target, vCount, iCount); |
| if (!arg.succeeded()) { |
| return false; |
| } |
| verts = reinterpret_cast<QuadVertex*>(arg.vertices()); |
| idxs = reinterpret_cast<uint16_t*>(arg.indices()); |
| |
| SkSTArray<kPreallocDrawCnt, Draw, true> draws; |
| create_vertices(segments, fanPt, &draws, verts, idxs); |
| |
| // Check devBounds |
| #ifdef SK_DEBUG |
| SkRect tolDevBounds = devBounds; |
| tolDevBounds.outset(SK_Scalar1 / 10000, SK_Scalar1 / 10000); |
| SkRect actualBounds; |
| actualBounds.set(verts[0].fPos, verts[1].fPos); |
| for (int i = 2; i < vCount; ++i) { |
| actualBounds.growToInclude(verts[i].fPos.fX, verts[i].fPos.fY); |
| } |
| SkASSERT(tolDevBounds.contains(actualBounds)); |
| #endif |
| |
| int vOffset = 0; |
| for (int i = 0; i < draws.count(); ++i) { |
| const Draw& draw = draws[i]; |
| target->drawIndexed(kTriangles_GrPrimitiveType, |
| vOffset, // start vertex |
| 0, // start index |
| draw.fVertexCnt, |
| draw.fIndexCnt, |
| &devBounds); |
| vOffset += draw.fVertexCnt; |
| } |
| |
| return true; |
| } |
