Fix artifacts on tiny stroked paths scaled up a lot.

Set doConsumeDegenerates to false when calling SkPath::Iter::next() for
all paths which are not in screen space. These lines are not degenerate
for world space paths.

Note: this change fixes only GrTessellatingPathRenderer and
GrDefaultPathRenderer. GrMSAAPathRenderer still exhibits the bug.

Bug: skia:6987
Change-Id: Ie3d494703211925c77052c68513948484e341486
Reviewed-on: https://skia-review.googlesource.com/37522
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Stephen White <senorblanco@chromium.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/gm/strokefill.cpp b/gm/strokefill.cpp
index 51936403e8..2e96cd7c36 100644
--- a/gm/strokefill.cpp
+++ b/gm/strokefill.cpp
@@ -358,3 +358,19 @@ DEF_SIMPLE_GM(bug339297, canvas, 640, 480) {
     paint.setStrokeWidth(1);
     canvas->drawPath(path, paint);
 }
+
+DEF_SIMPLE_GM(bug6987, canvas, 200, 200) {
+    SkPaint paint;
+    paint.setStyle(SkPaint::kStroke_Style);
+    paint.setStrokeWidth(0.0001f);
+    paint.setAntiAlias(true);
+    SkPath path;
+    canvas->save();
+    canvas->scale(50000.0f, 50000.0f);
+    path.moveTo(0.0005f, 0.0004f);
+    path.lineTo(0.0008f, 0.0010f);
+    path.lineTo(0.0002f, 0.0010f);
+    path.close();
+    canvas->drawPath(path, paint);
+    canvas->restore();
+}