ccpr: Don't assign inverse fill types to fan tessellations

Bug: skia:9453
Change-Id: Iabbd1089975efff4e89687e990128c075bf0ab9d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/243432
Commit-Queue: Chris Dalton <[email protected]>
Reviewed-by: Florin Malita <[email protected]>

Author: csmartdalton86

gm/inverseclip.cpp

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2019 Google LLC.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gm/gm.h"
+#include "include/core/SkCanvas.h"
+#include "include/core/SkPath.h"
+
+// Repro case for http://skbug.com/9453
+DEF_SIMPLE_GM(inverseclip, canvas, 400, 400) {
+    SkPath clip;
+    clip.setFillType(SkPath::kInverseWinding_FillType);
+    clip.moveTo(195.448f, 31);
+    clip.cubicTo(97.9925f, 31, 18.99f, 105.23f, 18.99f, 196.797f);
+    clip.cubicTo(18.99f, 288.365f, 97.9925f, 362.595f, 195.448f, 362.595f);
+    clip.cubicTo(292.905f, 362.595f, 371.905f, 288.365f, 371.905f, 196.797f);
+    clip.cubicTo(371.905f, 105.23f, 292.905f, 31, 195.448f, 31);
+    clip.close();
+    canvas->clipPath(clip, true);
+
+    SkPaint paint;
+    paint.setColor(SK_ColorBLUE);
+    canvas->drawRect(SkRect::MakeWH(400, 400), paint);
+}

gn/gm.gni

@@ -217,6 +217,7 @@ gm_sources = [
   "$_gm/imagesource2.cpp",
   "$_gm/internal_links.cpp",
   "$_gm/inversepaths.cpp",
+  "$_gm/inverseclip.cpp",
   "$_gm/jpg_color_cube.cpp",
   "$_gm/labyrinth.cpp",
   "$_gm/largeglyphblur.cpp",

src/gpu/ccpr/GrCCFiller.cpp

@@ -137,9 +137,10 @@ void GrCCFiller::PathInfo::tessellateFan(
         // count to the appropriate fill type later.
         fan.setFillType(SkPath::kWinding_FillType);
     } else {
-        // When counting winding numbers in the stencil buffer, it works to just tessellate the
-        // Redbook fan with the same fill type as the path.
-        fan.setFillType(originalPath.getFillType());
+        // When counting winding numbers in the stencil buffer, it works to use even/odd for the fan
+        // tessellation (where applicable). But we need to strip out inverse fill info because
+        // inverse-ness gets accounted for later on.
+        fan.setFillType(SkPath::ConvertToNonInverseFillType(originalPath.getFillType()));
     }
     SkASSERT(Verb::kBeginPath == verbs[verbsIdx]);
     for (int i = verbsIdx + 1; i < verbs.count(); ++i) {
@@ -175,9 +176,10 @@ void GrCCFiller::PathInfo::tessellateFan(
     }
 
     GrTessellator::WindingVertex* vertices = nullptr;
-    fFanTessellationCount =
-            GrTessellator::PathToVertices(fan, std::numeric_limits<float>::infinity(),
-                                          SkRect::Make(clippedDevIBounds), &vertices);
+    SkASSERT(!fan.isInverseFillType());
+    fFanTessellationCount = GrTessellator::PathToVertices(
+            fan, std::numeric_limits<float>::infinity(), SkRect::Make(clippedDevIBounds),
+            &vertices);
     if (fFanTessellationCount <= 0) {
         SkASSERT(0 == fFanTessellationCount);
         SkASSERT(nullptr == vertices);