Analytic AntiAlias for Convex Shapes

gm/aaa.cpp

+/*
+ * Copyright 2014 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 "SkPath.h"
+#include "SkScan.h"
+
+#define W   800
+#define H   800
+
+class AnalyticAntiAliasConvexGM : public skiagm::GM {
+public:
+    AnalyticAntiAliasConvexGM() {}
+
+protected:
+
+    SkString onShortName() override {
+        return SkString("analytic_antialias_convex");
+    }
+
+    SkISize onISize() override {
+        return SkISize::Make(W, H);
+    }
+
+    void onDraw(SkCanvas* canvas) override {
+        SkPaint p;
+        p.setColor(SK_ColorRED);
+        p.setAntiAlias(true);
+
+        canvas->clear(0xFFFFFFFF);
+
+        canvas->save();
+
+        int y = 0;
+
+        canvas->translate(0, y);
+        canvas->rotate(1);
+        GlobalAAConfig::getInstance().fUseAnalyticAA = true;
+        canvas->drawRectCoords(20, 20, 200, 200, p);
+        canvas->restore();
+
+        canvas->translate(200, y);
+        canvas->rotate(1);
+        GlobalAAConfig::getInstance().fUseAnalyticAA = false;
+        canvas->drawRectCoords(20, 20, 200, 200, p);
+        canvas->restore();
+
+        y += 200;
+
+        canvas->translate(0, y);
+        canvas->rotate(1);
+        GlobalAAConfig::getInstance().fUseAnalyticAA = true;
+        canvas->drawRectCoords(20, 20, 20.2, 200, p);
+        canvas->drawRectCoords(20, 200, 200, 200.1, p);
+        canvas->drawCircle(100, 100, 30, p);
+        canvas->restore();
+
+        canvas->translate(200, y);
+        canvas->rotate(1);
+        GlobalAAConfig::getInstance().fUseAnalyticAA = false;
+        canvas->drawRectCoords(20, 20, 20.2, 200, p);
+        canvas->drawRectCoords(20, 200, 200, 200.1, p);
+        canvas->drawCircle(100, 100, 30, p);
+        canvas->restore();
+    }
+
+private:
+    typedef skiagm::GM INHERITED;
+};
+
+DEF_GM( return new AnalyticAntiAliasConvexGM; )