re-chop if we fail on a big-bad-cubic
BUG=629455
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2159223005
Review-Url: https://codereview.chromium.org/2159223005
diff --git a/src/core/SkEdgeClipper.cpp b/src/core/SkEdgeClipper.cpp
index 85c519d..b5ac27a 100644
--- a/src/core/SkEdgeClipper.cpp
+++ b/src/core/SkEdgeClipper.cpp
@@ -263,9 +263,25 @@
if (pts[0].fY < clip.fTop) {
SkPoint tmp[7];
chop_mono_cubic_at_y(pts, clip.fTop, tmp);
+
+ /*
+ * For a large range in the points, we can do a poor job of chopping, such that the t
+ * we computed resulted in the lower cubic still being partly above the clip.
+ *
+ * If just the first or first 2 Y values are above the fTop, we can just smash them
+ * down. If the first 3 Ys are above fTop, we can't smash all 3, as that can really
+ * distort the cubic. In this case, we take the first output (tmp[3..6] and treat it as
+ * a guess, and re-chop against fTop. Then we fall through to checking if we need to
+ * smash the first 1 or 2 Y values.
+ */
+ if (tmp[3].fY < clip.fTop && tmp[4].fY < clip.fTop && tmp[5].fY < clip.fTop) {
+ SkPoint tmp2[4];
+ memcpy(tmp2, &tmp[3].fX, 4 * sizeof(SkPoint));
+ chop_mono_cubic_at_y(tmp2, clip.fTop, tmp);
+ }
+
// tmp[3, 4].fY should all be to the below clip.fTop.
- // Since we can't trust the numerics of
- // the chopper, we force those conditions now
+ // Since we can't trust the numerics of the chopper, we force those conditions now
tmp[3].fY = clip.fTop;
clamp_ge(tmp[4].fY, clip.fTop);
diff --git a/tests/PathTest.cpp b/tests/PathTest.cpp
index 44b6786..8f98e6a 100644
--- a/tests/PathTest.cpp
+++ b/tests/PathTest.cpp
@@ -4129,6 +4129,21 @@
}
};
+static void test_crbug_629455(skiatest::Reporter* reporter) {
+ SkPath path;
+ path.moveTo(0, 0);
+ path.cubicTo(SkBits2Float(0xcdcdcd00), SkBits2Float(0xcdcdcdcd),
+ SkBits2Float(0xcdcdcdcd), SkBits2Float(0xcdcdcdcd),
+ SkBits2Float(0x423fcdcd), SkBits2Float(0x40ed9341));
+// AKA: cubicTo(-4.31596e+08f, -4.31602e+08f, -4.31602e+08f, -4.31602e+08f, 47.951f, 7.42423f);
+ path.lineTo(0, 0);
+
+ auto surface = SkSurface::MakeRasterN32Premul(100, 100);
+ SkPaint paint;
+ paint.setAntiAlias(true);
+ surface->getCanvas()->drawPath(path, paint);
+}
+
static void test_interp(skiatest::Reporter* reporter) {
SkPath p1, p2, out;
REPORTER_ASSERT(reporter, p1.isInterpolatable(p2));
@@ -4177,6 +4192,7 @@
}
DEF_TEST(Paths, reporter) {
+ test_crbug_629455(reporter);
test_fuzz_crbug_627414(reporter);
test_path_crbug364224();