add GM case nonclosedpaths. The 2 bugs below showed some non-closed paths which are easy to get wrong rendering results. So add a GM case for this kind paths to avoid potential bugs to be introduced.
BUG=skia:1782
BUG=skia:1811
R=bsalomon@google.com, caryclark@google.com, reed@google.com, robertphillips@google.com
Author: yunchao.he@intel.com
Review URL: https://codereview.chromium.org/64173009
git-svn-id: http://skia.googlecode.com/svn/trunk@12206 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/nonclosedpaths.cpp b/gm/nonclosedpaths.cpp
new file mode 100644
index 0000000..bc37c54
--- /dev/null
+++ b/gm/nonclosedpaths.cpp
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "gm.h"
+#include "SkCanvas.h"
+#include "SkPath.h"
+
+namespace skiagm {
+
+// This GM tests a grab-bag of non-closed paths. All these paths look like
+// closed rects, but they don't call path.close(). Depending on the stroke
+// settings these slightly different paths give widely different results.
+class NonClosedPathsGM: public GM {
+public:
+ NonClosedPathsGM() {}
+
+ enum ClosureType {
+ TotallyNonClosed, // The last point doesn't coincide with the first one in the contour.
+ // The path looks not closed at all.
+
+ FakeCloseCorner, // The last point coincides with the first one at a corner.
+ // The path looks closed, but final rendering has 2 ends with cap.
+
+ FakeCloseMiddle, // The last point coincides with the first one in the middle of a line.
+ // The path looks closed, and the final rendering looks closed too.
+
+ kClosureTypeCount
+ };
+
+protected:
+ virtual SkString onShortName() SK_OVERRIDE {
+ return SkString("nonclosedpaths");
+ }
+
+ // 12 * 18 + 3 cases, every case is 100 * 100 pixels.
+ virtual SkISize onISize() SK_OVERRIDE {
+ return SkISize::Make(1220, 1920);
+ }
+
+ // Use rect-like geometry for non-closed path, for right angles make it
+ // easier to show the visual difference of lineCap and lineJoin.
+ static void MakePath(SkPath* path, ClosureType type) {
+ if (FakeCloseMiddle == type) {
+ path->moveTo(30, 50);
+ path->lineTo(30, 30);
+ } else {
+ path->moveTo(30, 30);
+ }
+ path->lineTo(70, 30);
+ path->lineTo(70, 70);
+ path->lineTo(30, 70);
+ path->lineTo(30, 50);
+ if (FakeCloseCorner == type) {
+ path->lineTo(30, 30);
+ }
+ }
+
+ // Set the location for the current test on the canvas
+ static void SetLocation(SkCanvas* canvas, int counter, int lineNum) {
+ SkScalar x = SK_Scalar1 * 100 * (counter % lineNum) + 10 + SK_Scalar1 / 4;
+ SkScalar y = SK_Scalar1 * 100 * (counter / lineNum) + 10 + 3 * SK_Scalar1 / 4;
+ canvas->translate(x, y);
+ }
+
+ virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+ // Stroke widths are:
+ // 0(may use hairline rendering), 10(common case for stroke-style)
+ // 40 and 50(>= geometry width/height, make the contour filled in fact)
+ static const int kStrokeWidth[] = {0, 10, 40, 50};
+ size_t numWidths = SK_ARRAY_COUNT(kStrokeWidth);
+
+ static const SkPaint::Style kStyle[] = {
+ SkPaint::kStroke_Style, SkPaint::kStrokeAndFill_Style
+ };
+
+ static const SkPaint::Cap kCap[] = {
+ SkPaint::kButt_Cap, SkPaint::kRound_Cap, SkPaint::kSquare_Cap
+ };
+
+ static const SkPaint::Join kJoin[] = {
+ SkPaint::kMiter_Join, SkPaint::kRound_Join, SkPaint::kBevel_Join
+ };
+
+ static const ClosureType kType[] = {
+ TotallyNonClosed, FakeCloseCorner, FakeCloseMiddle
+ };
+
+ int counter = 0;
+ SkPaint paint;
+ paint.setAntiAlias(true);
+
+ // For stroke style painter and fill-and-stroke style painter
+ for (size_t type = 0; type < kClosureTypeCount; ++type) {
+ for (size_t style = 0; style < SK_ARRAY_COUNT(kStyle); ++style) {
+ for (size_t cap = 0; cap < SK_ARRAY_COUNT(kCap); ++cap) {
+ for (size_t join = 0; join < SK_ARRAY_COUNT(kJoin); ++join) {
+ for (size_t width = 0; width < numWidths; ++width) {
+ canvas->save();
+ SetLocation(canvas, counter, SkPaint::kJoinCount * numWidths);
+
+ SkPath path;
+ MakePath(&path, kType[type]);
+
+ paint.setStyle(kStyle[style]);
+ paint.setStrokeCap(kCap[cap]);
+ paint.setStrokeJoin(kJoin[join]);
+ paint.setStrokeWidth(SkIntToScalar(kStrokeWidth[width]));
+
+ canvas->drawPath(path, paint);
+ canvas->restore();
+ ++counter;
+ }
+ }
+ }
+ }
+ }
+
+ // For fill style painter
+ paint.setStyle(SkPaint::kFill_Style);
+ for (size_t type = 0; type < kClosureTypeCount; ++type) {
+ canvas->save();
+ SetLocation(canvas, counter, SkPaint::kJoinCount * numWidths);
+
+ SkPath path;
+ MakePath(&path, kType[type]);
+
+ canvas->drawPath(path, paint);
+ canvas->restore();
+ ++counter;
+ }
+ }
+
+private:
+ typedef GM INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+DEF_GM(return new NonClosedPathsGM;)
+
+}
diff --git a/gyp/gmslides.gypi b/gyp/gmslides.gypi
index a18ad54..542de0f 100644
--- a/gyp/gmslides.gypi
+++ b/gyp/gmslides.gypi
@@ -91,6 +91,7 @@
'../gm/morphology.cpp',
'../gm/nested.cpp',
'../gm/ninepatchstretch.cpp',
+ '../gm/nonclosedpaths.cpp',
'../gm/offsetimagefilter.cpp',
'../gm/optimizations.cpp',
'../gm/ovals.cpp',