commit d952a9929b2dc826955249c755b6fed5627491c2
author Jim Van Verth <jvanverth@google.com> Thu Apr 20 17:25:26 2017 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Fri Apr 21 13:28:45 2017 +0000
tree ef150bfcaea7e1779be3f6b15f13646f8650854a
parent 2af746c1e74af30d0fb02d5c35a178e61d152965

Fix reflected ovals.

Addresses an issue with ovals transformed by a matrix with a reflection.
Also adds a further check for circles to ensure that teeny tiny ovals
(sizes < SK_ScalarNearlyZero) aren't treated as circles.

Change-Id: Ie50e4a98365eba7c23e53e68886ebac981ed1def
Reviewed-on: https://skia-review.googlesource.com/13989
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>

src/gpu/ops/GrOvalOpFactory.cpp

diff --git a/src/gpu/ops/GrOvalOpFactory.cpp b/src/gpu/ops/GrOvalOpFactory.cpp
index e00ee0b..71f8bb0 100644
--- a/src/gpu/ops/GrOvalOpFactory.cpp
+++ b/src/gpu/ops/GrOvalOpFactory.cpp
@@ -1172,8 +1172,8 @@
         SkScalar ellipseXRadius = SkScalarHalf(ellipse.width());
         SkScalar ellipseYRadius = SkScalarHalf(ellipse.height());
         SkScalar xRadius = SkScalarAbs(viewMatrix[SkMatrix::kMScaleX] * ellipseXRadius +
-                                       viewMatrix[SkMatrix::kMSkewY] * ellipseYRadius);
-        SkScalar yRadius = SkScalarAbs(viewMatrix[SkMatrix::kMSkewX] * ellipseXRadius +
+                                       viewMatrix[SkMatrix::kMSkewX] * ellipseYRadius);
+        SkScalar yRadius = SkScalarAbs(viewMatrix[SkMatrix::kMSkewY] * ellipseXRadius +
                                        viewMatrix[SkMatrix::kMScaleY] * ellipseYRadius);
 
         // do (potentially) anisotropic mapping of stroke
@@ -2385,7 +2385,8 @@
                                                                 const GrShaderCaps* shaderCaps) {
     // we can draw circles
     SkScalar width = oval.width();
-    if (SkScalarNearlyEqual(width, oval.height()) && circle_stays_circle(viewMatrix)) {
+    if (width > SK_ScalarNearlyZero && SkScalarNearlyEqual(width, oval.height()) &&
+        circle_stays_circle(viewMatrix)) {
         SkPoint center = {oval.centerX(), oval.centerY()};
         return CircleOp::Make(color, viewMatrix, center, width / 2.f, GrStyle(stroke, nullptr));
     }