commit b8de1f46594c3cd9c537f0b128c6d6eb30a9f463
author robertphillips <robertphillips@google.com> Mon Feb 23 11:17:01 2015 -0800
committer Commit bot <commit-bot@chromium.org> Mon Feb 23 11:17:01 2015 -0800
tree 27d33b3f054cb71848dd8d712db5923632c731b1
parent 1a9600f2537ad62e85529801a634167f2913bc24

Reset conicWeights in SkPath::consumeDegenerateSegments when rewinding to last Move op

Without this patch the iterator can end up running off the end of the conic weights if there is a mixture of degenerate and non-degenerate ops

Note: we might want to suppress the generation of degenerate conics and lines in SkPath::addRRect

BUG=459897

Review URL: https://codereview.chromium.org/954453003

src/core/SkPath.cpp

diff --git a/src/core/SkPath.cpp b/src/core/SkPath.cpp
index de3d297..0b796fc 100644
--- a/src/core/SkPath.cpp
+++ b/src/core/SkPath.cpp
@@ -1660,6 +1660,7 @@
     // forward before the next move is seen
     const uint8_t* lastMoveVerb = 0;
     const SkPoint* lastMovePt = 0;
+    const SkScalar* lastMoveWeight = NULL;
     SkPoint lastPt = fLastPt;
     while (fVerbs != fVerbStop) {
         unsigned verb = *(fVerbs - 1); // fVerbs is one beyond the current verb
@@ -1668,6 +1669,7 @@
                 // Keep a record of this most recent move
                 lastMoveVerb = fVerbs;
                 lastMovePt = fPts;
+                lastMoveWeight = fConicWeights;
                 lastPt = fPts[0];
                 fVerbs--;
                 fPts++;
@@ -1688,6 +1690,7 @@
                     if (lastMoveVerb) {
                         fVerbs = lastMoveVerb;
                         fPts = lastMovePt;
+                        fConicWeights = lastMoveWeight;
                         return;
                     }
                     return;
@@ -1703,6 +1706,7 @@
                     if (lastMoveVerb) {
                         fVerbs = lastMoveVerb;
                         fPts = lastMovePt;
+                        fConicWeights = lastMoveWeight;
                         return;
                     }
                     return;
@@ -1718,6 +1722,7 @@
                     if (lastMoveVerb) {
                         fVerbs = lastMoveVerb;
                         fPts = lastMovePt;
+                        fConicWeights = lastMoveWeight;
                         return;
                     }
                     return;

tests/PathTest.cpp

diff --git a/tests/PathTest.cpp b/tests/PathTest.cpp
index 7db65a8..a868d93 100644
--- a/tests/PathTest.cpp
+++ b/tests/PathTest.cpp
@@ -2475,6 +2475,20 @@
     REPORTER_ASSERT(reporter, SkPath::kDone_Verb == iter.next(pts, true));
 
     // The GM degeneratesegments.cpp test is more extensive
+
+    // Test out mixed degenerate and non-degenerate geometry with Conics
+    const SkVector radii[4] = { { 0, 0 }, { 0, 0 }, { 0, 0 }, { 100, 100 } };
+    SkRect r = SkRect::MakeWH(100, 100);
+    SkRRect rr;
+    rr.setRectRadii(r, radii);
+    p.reset();
+    p.addRRect(rr);
+    iter.setPath(p, false);
+    REPORTER_ASSERT(reporter, SkPath::kMove_Verb == iter.next(pts));
+    REPORTER_ASSERT(reporter, SkPath::kLine_Verb == iter.next(pts));
+    REPORTER_ASSERT(reporter, SkPath::kLine_Verb == iter.next(pts));
+    REPORTER_ASSERT(reporter, SkPath::kConic_Verb == iter.next(pts));
+    REPORTER_ASSERT(reporter, SK_ScalarRoot2Over2 == iter.conicWeight());
 }
 
 static void test_raw_iter(skiatest::Reporter* reporter) {