Implement caching of stroked paths in the tessellating path renderer.

src/gpu/GrTessellatingPathRenderer.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrTessellatingPathRenderer.h"
 
 #include "GrBatch.h"
@@ skipping 1366 matching lines @@
     GrUniqueKeyInvalidatedMessage fMsg;
 
     void onChange() override {
         SkMessageBus<GrUniqueKeyInvalidatedMessage>::Post(fMsg);
     }
 };
 
 }  // namespace
 
 bool GrTessellatingPathRenderer::onCanDrawPath(const CanDrawPathArgs& args) const {
-    // This path renderer can draw all fill styles, but does not do antialiasing. It can do convex
-    // and concave paths, but we'll leave the convex ones to simpler algorithms.
-    return args.fStroke->isFillStyle() && !args.fAntiAlias && !args.fPath->isConvex();
+    // This path renderer can draw all fill styles, all stroke styles except hairlines, but does
+    // not do antialiasing. It can do convex and concave paths, but we'll leave the convex ones to
+    // simpler algorithms.
+    return !args.fStroke->isHairlineStyle() && !args.fAntiAlias && !args.fPath->isConvex();
 }
 
 class TessellatingPathBatch : public GrBatch {
 public:
 
     static GrBatch* Create(const GrColor& color,
                            const SkPath& path,
+                           const GrStrokeInfo& stroke,
                            const SkMatrix& viewMatrix,
                            SkRect clipBounds) {
-        return SkNEW_ARGS(TessellatingPathBatch, (color, path, viewMatrix, clipBounds));
+        return SkNEW_ARGS(TessellatingPathBatch, (color, path, stroke, viewMatrix, clipBounds));
     }
 
     const char* name() const override { return "TessellatingPathBatch"; }
 
     void getInvariantOutputColor(GrInitInvariantOutput* out) const override {
         out->setKnownFourComponents(fColor);
     }
 
     void getInvariantOutputCoverage(GrInitInvariantOutput* out) const override {
         out->setUnknownSingleComponent();
     }
 
     void initBatchTracker(const GrPipelineInfo& init) override {
         // Handle any color overrides
         if (!init.readsColor()) {
             fColor = GrColor_ILLEGAL;
         }
         init.getOverrideColorIfSet(&fColor);
         fPipelineInfo = init;
     }
 
     int tessellate(GrUniqueKey* key,
                    GrResourceProvider* resourceProvider,
                    SkAutoTUnref<GrVertexBuffer>& vertexBuffer) {
-        SkRect pathBounds = fPath.getBounds();
+        SkPath path;
+        GrStrokeInfo stroke(fStroke);
+        if (stroke.isDashed()) {
+            if (!stroke.applyDashToPath(&path, &stroke, fPath)) {
+                return 0;
+            }
+        } else {
+            path = fPath;
+        }
+        if (!stroke.isFillStyle()) {
+            stroke.setResScale(SkScalarAbs(fViewMatrix.getMaxScale()));
+            if (!stroke.applyToPath(&path, path)) {
+                return 0;
+            }
+            stroke.setFillStyle();
+        }
+        SkRect pathBounds = path.getBounds();
         Comparator c;
         if (pathBounds.width() > pathBounds.height()) {
             c.sweep_lt = sweep_lt_horiz;
             c.sweep_gt = sweep_gt_horiz;
         } else {
             c.sweep_lt = sweep_lt_vert;
             c.sweep_gt = sweep_gt_vert;
         }
         SkScalar screenSpaceTol = GrPathUtils::kDefaultTolerance;
         SkScalar tol = GrPathUtils::scaleToleranceToSrc(screenSpaceTol, fViewMatrix, pathBounds);
         int contourCnt;
-        int maxPts = GrPathUtils::worstCasePointCount(fPath, &contourCnt, tol);
+        int maxPts = GrPathUtils::worstCasePointCount(path, &contourCnt, tol);
         if (maxPts <= 0) {
             return 0;
         }
         if (maxPts > ((int)SK_MaxU16 + 1)) {
             SkDebugf("Path not rendered, too many verts (%d)\n", maxPts);
             return 0;
         }
-        SkPath::FillType fillType = fPath.getFillType();
+        SkPath::FillType fillType = path.getFillType();
         if (SkPath::IsInverseFillType(fillType)) {
             contourCnt++;
         }
 
         LOG("got %d pts, %d contours\n", maxPts, contourCnt);
         SkAutoTDeleteArray<Vertex*> contours(SkNEW_ARRAY(Vertex *, contourCnt));
 
         // For the initial size of the chunk allocator, estimate based on the point count:
         // one vertex per point for the initial passes, plus two for the vertices in the
         // resulting Polys, since the same point may end up in two Polys.  Assume minimal
         // connectivity of one Edge per Vertex (will grow for intersections).
         SkChunkAlloc alloc(maxPts * (3 * sizeof(Vertex) + sizeof(Edge)));
         bool isLinear;
-        path_to_contours(fPath, tol, fClipBounds, contours.get(), alloc, &isLinear);
+        path_to_contours(path, tol, fClipBounds, contours.get(), alloc, &isLinear);
         Poly* polys;
         polys = contours_to_polys(contours.get(), contourCnt, c, alloc);
         int count = 0;
         for (Poly* poly = polys; poly; poly = poly->fNext) {
             if (apply_fill_type(fillType, poly->fWinding) && poly->fCount >= 3) {
                 count += (poly->fCount - 2) * (WIREFRAME ? 6 : 3);
             }
         }
         if (0 == count) {
             return 0;
@@ skipping 27 matching lines @@
         }
         return actualCount;
     }
 
     void generateGeometry(GrBatchTarget* batchTarget, const GrPipeline* pipeline) override {
         // construct a cache key from the path's genID and the view matrix
         static const GrUniqueKey::Domain kDomain = GrUniqueKey::GenerateDomain();
         GrUniqueKey key;
         int clipBoundsSize32 =
             fPath.isInverseFillType() ? sizeof(fClipBounds) / sizeof(uint32_t) : 0;
-        GrUniqueKey::Builder builder(&key, kDomain, 2 + clipBoundsSize32);
+        int strokeDataSize32 = fStroke.computeUniqueKeyFragmentData32Cnt();
+        GrUniqueKey::Builder builder(&key, kDomain, 2 + clipBoundsSize32 + strokeDataSize32);
         builder[0] = fPath.getGenerationID();
         builder[1] = fPath.getFillType();
         // For inverse fills, the tessellation is dependent on clip bounds.
         if (fPath.isInverseFillType()) {
             memcpy(&builder[2], &fClipBounds, sizeof(fClipBounds));
         }
+        fStroke.asUniqueKeyFragment(&builder[2 + clipBoundsSize32]);
         builder.finish();
         GrResourceProvider* rp = batchTarget->resourceProvider();
         SkAutoTUnref<GrVertexBuffer> vertexBuffer(rp->findAndRefTByUniqueKey<GrVertexBuffer>(key));
         int actualCount;
         SkScalar screenSpaceTol = GrPathUtils::kDefaultTolerance;
         SkScalar tol = GrPathUtils::scaleToleranceToSrc(
             screenSpaceTol, fViewMatrix, fPath.getBounds());
         if (!cache_match(vertexBuffer.get(), tol, &actualCount)) {
             actualCount = tessellate(&key, rp, vertexBuffer);
         }
@@ skipping 31 matching lines @@
         batchTarget->draw(vertices);
     }
 
     bool onCombineIfPossible(GrBatch*) override {
         return false;
     }
 
 private:
     TessellatingPathBatch(const GrColor& color,
                           const SkPath& path,
+                          const GrStrokeInfo& stroke,
                           const SkMatrix& viewMatrix,
                           const SkRect& clipBounds)
       : fColor(color)
       , fPath(path)
+      , fStroke(stroke)
       , fViewMatrix(viewMatrix)
       , fClipBounds(clipBounds) {
         this->initClassID<TessellatingPathBatch>();
 
         fBounds = path.getBounds();
         viewMatrix.mapRect(&fBounds);
     }
 
     GrColor        fColor;
     SkPath         fPath;
+    GrStrokeInfo   fStroke;
     SkMatrix       fViewMatrix;
     SkRect         fClipBounds; // in source space
     GrPipelineInfo fPipelineInfo;
 };
 
 bool GrTessellatingPathRenderer::onDrawPath(const DrawPathArgs& args) {
     SkASSERT(!args.fAntiAlias);
     const GrRenderTarget* rt = args.fPipelineBuilder->getRenderTarget();
     if (NULL == rt) {
         return false;
     }
 
     SkIRect clipBoundsI;
     args.fPipelineBuilder->clip().getConservativeBounds(rt, &clipBoundsI);
     SkRect clipBounds = SkRect::Make(clipBoundsI);
     SkMatrix vmi;
     if (!args.fViewMatrix->invert(&vmi)) {
         return false;
     }
     vmi.mapRect(&clipBounds);
     SkAutoTUnref<GrBatch> batch(TessellatingPathBatch::Create(args.fColor, *args.fPath,
-                                                              *args.fViewMatrix, clipBounds));
+                                                              *args.fStroke, *args.fViewMatrix,
+                                                              clipBounds));
     args.fTarget->drawBatch(*args.fPipelineBuilder, batch);
 
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 #ifdef GR_TEST_UTILS
 
 BATCH_TEST_DEFINE(TesselatingPathBatch) {
     GrColor color = GrRandomColor(random);
     SkMatrix viewMatrix = GrTest::TestMatrixInvertible(random);
     SkPath path = GrTest::TestPath(random);
     SkRect clipBounds = GrTest::TestRect(random);
     SkMatrix vmi;
     bool result = viewMatrix.invert(&vmi);
     if (!result) {
         SkFAIL("Cannot invert matrix\n");
     }
     vmi.mapRect(&clipBounds);
-    return TessellatingPathBatch::Create(color, path, viewMatrix, clipBounds);
+    SkPaint strokePaint;

[bsalomon, 2015/08/05 18:53:51]

This doesn't look like it is actually initialized to set stroking params.

[Stephen White, 2015/08/05 18:57:39]

True.. I was looking for something that would generate me a random SkPaint or
random GrStrokeInfo, but didn't find one. Did I miss it, or should I write one?

+    GrStrokeInfo stroke(strokePaint);
+    return TessellatingPathBatch::Create(color, path, stroke, viewMatrix, clipBounds);
 }
 
 #endif