Fix round cap approximation to understand scale
bug:19772120
Change-Id: I7b944faed1d1e8d5f55453802da57679217d9d9a
diff --git a/libs/hwui/PathTessellator.cpp b/libs/hwui/PathTessellator.cpp
index c1f61d6..7cafd7b 100644
--- a/libs/hwui/PathTessellator.cpp
+++ b/libs/hwui/PathTessellator.cpp
@@ -151,13 +151,11 @@
*/
inline int capExtraDivisions() const {
if (cap == SkPaint::kRound_Cap) {
+ // always use 2 points for hairline
if (halfStrokeWidth == 0.0f) return 2;
- // ROUND_CAP_THRESH is the maximum error for polygonal approximation of the round cap
- const float errConst = (-ROUND_CAP_THRESH / halfStrokeWidth + 1);
- const float targetCosVal = 2 * errConst * errConst - 1;
- int neededDivisions = (int)(ceilf(PI / acos(targetCosVal)/2)) * 2;
- return neededDivisions;
+ float threshold = MathUtils::min(inverseScaleX, inverseScaleY) * ROUND_CAP_THRESH;
+ return MathUtils::divisionsNeededToApproximateArc(halfStrokeWidth, PI, threshold);
}
return 0;
}