bool GrTesselatedPathRenderer::onDrawPath(const SkPath& path,
GrPathFill fill,
const GrVec* translate,
GrDrawTarget* target,
GrDrawState::StageMask stageMask,
bool antiAlias) {
GrDrawTarget::AutoStateRestore asr(target);
GrDrawState* drawState = target->drawState();
// face culling doesn't make sense here
GrAssert(GrDrawState::kBoth_DrawFace == drawState->getDrawFace());
GrMatrix viewM = drawState->getViewMatrix();
GrScalar tol = GR_Scalar1;
tol = GrPathUtils::scaleToleranceToSrc(tol, viewM, path.getBounds());
GrScalar tolSqd = GrMul(tol, tol);
int subpathCnt;
int maxPts = GrPathUtils::worstCasePointCount(path, &subpathCnt, tol);
GrVertexLayout layout = 0;
for (int s = 0; s < GrDrawState::kNumStages; ++s) {
if ((1 << s) & stageMask) {
layout |= GrDrawTarget::StagePosAsTexCoordVertexLayoutBit(s);
}
}
bool inverted = GrIsFillInverted(fill);
if (inverted) {
maxPts += 4;
subpathCnt++;
}
if (maxPts > USHRT_MAX) {
return false;
}
SkAutoSTMalloc<8, GrPoint> baseMem(maxPts);
GrPoint* base = baseMem;
GrPoint* vert = base;
GrPoint* subpathBase = base;
SkAutoSTMalloc<8, uint16_t> subpathVertCount(subpathCnt);
GrPoint pts[4];
SkPath::Iter iter(path, false);
bool first = true;
int subpath = 0;
for (;;) {
switch (iter.next(pts)) {
case kMove_PathCmd:
if (!first) {
subpathVertCount[subpath] = vert-subpathBase;
subpathBase = vert;
++subpath;
}
*vert = pts[0];
vert++;
break;
case kLine_PathCmd:
*vert = pts[1];
vert++;
break;
case kQuadratic_PathCmd: {
GrPathUtils::generateQuadraticPoints(pts[0], pts[1], pts[2],
tolSqd, &vert,
GrPathUtils::quadraticPointCount(pts, tol));
break;
}
case kCubic_PathCmd: {
GrPathUtils::generateCubicPoints(pts[0], pts[1], pts[2], pts[3],
tolSqd, &vert,
GrPathUtils::cubicPointCount(pts, tol));
break;
}
case kClose_PathCmd:
break;
case kEnd_PathCmd:
subpathVertCount[subpath] = vert-subpathBase;
++subpath; // this could be only in debug
goto FINISHED;
}
first = false;
}
FINISHED:
if (NULL != translate && 0 != translate->fX && 0 != translate->fY) {
for (int i = 0; i < vert - base; i++) {
base[i].offset(translate->fX, translate->fY);
}
}
if (inverted) {
GrRect bounds;
GrAssert(NULL != drawState->getRenderTarget());
bounds.setLTRB(0, 0,
GrIntToScalar(drawState->getRenderTarget()->width()),
GrIntToScalar(drawState->getRenderTarget()->height()));
GrMatrix vmi;
if (drawState->getViewInverse(&vmi)) {
vmi.mapRect(&bounds);
}
*vert++ = GrPoint::Make(bounds.fLeft, bounds.fTop);
*vert++ = GrPoint::Make(bounds.fLeft, bounds.fBottom);
*vert++ = GrPoint::Make(bounds.fRight, bounds.fBottom);
*vert++ = GrPoint::Make(bounds.fRight, bounds.fTop);
subpathVertCount[subpath++] = 4;
}
GrAssert(subpath == subpathCnt);
GrAssert((vert - base) <= maxPts);
size_t count = vert - base;
if (count < 3) {
return true;
}
if (subpathCnt == 1 && !inverted && path.isConvex()) {
if (antiAlias) {
GrEdgeArray edges;
GrMatrix inverse, matrix = drawState->getViewMatrix();
drawState->getViewInverse(&inverse);
count = computeEdgesAndIntersect(matrix, inverse, base, count, &edges, 0.0f);
size_t maxEdges = target->getMaxEdges();
if (count == 0) {
return true;
}
if (count <= maxEdges) {
// All edges fit; upload all edges and draw all verts as a fan
target->setVertexSourceToArray(layout, base, count);
drawState->setEdgeAAData(&edges[0], count);
target->drawNonIndexed(kTriangleFan_PrimitiveType, 0, count);
} else {
// Upload "maxEdges" edges and verts at a time, and draw as
// separate fans
for (size_t i = 0; i < count - 2; i += maxEdges - 2) {
edges[i] = edges[0];
base[i] = base[0];
int size = GR_CT_MIN(count - i, maxEdges);
target->setVertexSourceToArray(layout, &base[i], size);
drawState->setEdgeAAData(&edges[i], size);
target->drawNonIndexed(kTriangleFan_PrimitiveType, 0, size);
}
}
drawState->setEdgeAAData(NULL, 0);
} else {
target->setVertexSourceToArray(layout, base, count);
target->drawNonIndexed(kTriangleFan_PrimitiveType, 0, count);
}
return true;
}
if (antiAlias) {
// Run the tesselator once to get the boundaries.
GrBoundaryTess btess(count, fill_type_to_glu_winding_rule(fill));
btess.addVertices(base, subpathVertCount, subpathCnt);
GrMatrix inverse, matrix = drawState->getViewMatrix();
if (!drawState->getViewInverse(&inverse)) {
return false;
}
if (btess.vertices().count() > USHRT_MAX) {
return false;
}
// Inflate the boundary, and run the tesselator again to generate
// interior polys.
const GrPointArray& contourPoints = btess.contourPoints();
const GrIndexArray& contours = btess.contours();
GrEdgePolygonTess ptess(contourPoints.count(), GLU_TESS_WINDING_NONZERO, matrix);
size_t i = 0;
Sk_gluTessBeginPolygon(ptess.tess(), &ptess);
for (int contour = 0; contour < contours.count(); ++contour) {
int count = contours[contour];
GrEdgeArray edges;
int newCount = computeEdgesAndIntersect(matrix, inverse, &btess.contourPoints()[i], count, &edges, 1.0f);
Sk_gluTessBeginContour(ptess.tess());
for (int j = 0; j < newCount; j++) {
ptess.addVertex(contourPoints[i + j], ptess.vertices().count());
}
i += count;
Sk_gluTessEndContour(ptess.tess());
}
Sk_gluTessEndPolygon(ptess.tess());
if (ptess.vertices().count() > USHRT_MAX) {
return false;
}
// Draw the resulting polys and upload their edge data.
drawState->enableState(GrDrawState::kEdgeAAConcave_StateBit);
const GrPointArray& vertices = ptess.vertices();
const GrIndexArray& indices = ptess.indices();
const GrDrawState::Edge* edges = ptess.edges();
GR_DEBUGASSERT(indices.count() % 3 == 0);
for (int i = 0; i < indices.count(); i += 3) {
GrPoint tri_verts[3];
int index0 = indices[i];
int index1 = indices[i + 1];
int index2 = indices[i + 2];
tri_verts[0] = vertices[index0];
tri_verts[1] = vertices[index1];
tri_verts[2] = vertices[index2];
GrDrawState::Edge tri_edges[6];
int t = 0;
const GrDrawState::Edge& edge0 = edges[index0 * 2];
const GrDrawState::Edge& edge1 = edges[index0 * 2 + 1];
const GrDrawState::Edge& edge2 = edges[index1 * 2];
const GrDrawState::Edge& edge3 = edges[index1 * 2 + 1];
const GrDrawState::Edge& edge4 = edges[index2 * 2];
const GrDrawState::Edge& edge5 = edges[index2 * 2 + 1];
if (validEdge(edge0) && validEdge(edge1)) {
tri_edges[t++] = edge0;
tri_edges[t++] = edge1;
}
if (validEdge(edge2) && validEdge(edge3)) {
tri_edges[t++] = edge2;
tri_edges[t++] = edge3;
}
if (validEdge(edge4) && validEdge(edge5)) {
tri_edges[t++] = edge4;
tri_edges[t++] = edge5;
}
drawState->setEdgeAAData(&tri_edges[0], t);
target->setVertexSourceToArray(layout, &tri_verts[0], 3);
target->drawNonIndexed(kTriangles_PrimitiveType, 0, 3);
}
drawState->setEdgeAAData(NULL, 0);
drawState->disableState(GrDrawState::kEdgeAAConcave_StateBit);
return true;
}
GrPolygonTess ptess(count, fill_type_to_glu_winding_rule(fill));
ptess.addVertices(base, subpathVertCount, subpathCnt);
const GrPointArray& vertices = ptess.vertices();
const GrIndexArray& indices = ptess.indices();
if (indices.count() > 0) {
target->setVertexSourceToArray(layout, vertices.begin(), vertices.count());
target->setIndexSourceToArray(indices.begin(), indices.count());
target->drawIndexed(kTriangles_PrimitiveType,
0,
0,
vertices.count(),
indices.count());
}
return true;
}
