commit a5ef39726a7b8e54d295aa8336e7d874bc33f436
author Jim Van Verth <jvanverth@google.com> Wed May 01 13:28:07 2019 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Wed May 01 18:02:05 2019 +0000
tree 77feca6eefd7d26d0bf2ce7543ee46035082d1a3
parent b75be23bc485b3f87c7a2d3574ad5ec57c09ad51

More polyutils fixes

Bug: chromium:954891, oss-fuzz:14079
Change-Id: Ia1ee0a15ab4bfc93e67188ff02e6aa436432a3be
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/211602
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>

src/utils/SkShadowTessellator.cpp

diff --git a/src/utils/SkShadowTessellator.cpp b/src/utils/SkShadowTessellator.cpp
index a43a337..6dc7a75 100644
--- a/src/utils/SkShadowTessellator.cpp
+++ b/src/utils/SkShadowTessellator.cpp
@@ -25,7 +25,7 @@
  */
 class SkBaseShadowTessellator {
 public:
-    SkBaseShadowTessellator(const SkPoint3& zPlaneParams, bool transparent);
+    SkBaseShadowTessellator(const SkPoint3& zPlaneParams, const SkRect& bounds, bool transparent);
     virtual ~SkBaseShadowTessellator() {}
 
     sk_sp<SkVertices> releaseVertices() {
@@ -99,6 +99,7 @@
     SkTDArray<SkPoint>   fClipPolygon;
     SkTDArray<SkVector>  fClipVectors;
 
+    SkRect              fPathBounds;
     SkPoint             fCentroid;
     SkScalar            fArea;
     SkScalar            fLastArea;
@@ -155,8 +156,10 @@
     return v0.cross(v1);
 }
 
-SkBaseShadowTessellator::SkBaseShadowTessellator(const SkPoint3& zPlaneParams, bool transparent)
+SkBaseShadowTessellator::SkBaseShadowTessellator(const SkPoint3& zPlaneParams, const SkRect& bounds,
+                                                 bool transparent)
         : fZPlaneParams(zPlaneParams)
+        , fPathBounds(bounds)
         , fCentroid({0, 0})
         , fArea(0)
         , fLastArea(0)
@@ -559,7 +562,7 @@
     SkTDArray<SkPoint> umbraPolygon;
     SkTDArray<int> umbraIndices;
     umbraIndices.setReserve(fPathPolygon.count());
-    if (!SkOffsetSimplePolygon(&fPathPolygon[0], fPathPolygon.count(), inset,
+    if (!SkOffsetSimplePolygon(&fPathPolygon[0], fPathPolygon.count(), fPathBounds, inset,
                                &umbraPolygon, &umbraIndices)) {
         // TODO: figure out how to handle this case
         return false;
@@ -570,7 +573,7 @@
     SkTDArray<int> penumbraIndices;
     penumbraPolygon.setReserve(umbraPolygon.count());
     penumbraIndices.setReserve(umbraPolygon.count());
-    if (!SkOffsetSimplePolygon(&fPathPolygon[0], fPathPolygon.count(), -outset,
+    if (!SkOffsetSimplePolygon(&fPathPolygon[0], fPathPolygon.count(), fPathBounds, -outset,
                                &penumbraPolygon, &penumbraIndices)) {
         // TODO: figure out how to handle this case
         return false;
@@ -904,12 +907,14 @@
                                                        const SkMatrix& ctm,
                                                        const SkPoint3& zPlaneParams,
                                                        bool transparent)
-        : INHERITED(zPlaneParams, transparent) {
+        : INHERITED(zPlaneParams, path.getBounds(), transparent) {
     // Set base colors
-    auto baseZ = heightFunc(path.getBounds().centerX(), path.getBounds().centerY());
+    auto baseZ = heightFunc(fPathBounds.centerX(), fPathBounds.centerY());
     // umbraColor is the interior value, penumbraColor the exterior value.
     auto outset = SkDrawShadowMetrics::AmbientBlurRadius(baseZ);
     auto inset = outset * SkDrawShadowMetrics::AmbientRecipAlpha(baseZ) - outset;
+    inset = SkScalarPin(inset, 0, SkTMin(path.getBounds().width(),
+                                         path.getBounds().height()));
 
     if (!this->computePathPolygon(path, ctm)) {
         return;
@@ -999,7 +1004,7 @@
                                                  const SkPoint3& zPlaneParams,
                                                  const SkPoint3& lightPos, SkScalar lightRadius,
                                                  bool transparent)
-    : INHERITED(zPlaneParams, transparent) {
+    : INHERITED(zPlaneParams, path.getBounds(), transparent) {
 
     // Compute the blur radius, scale and translation for the spot shadow.
     SkMatrix shadowTransform;