Adding unit test for verifying copy on write in SkSurface + bug fix in SkCanvas::clear

tests/SurfaceTest.cpp

Index: tests/SurfaceTest.cpp
===================================================================
--- tests/SurfaceTest.cpp	(revision 0)
+++ tests/SurfaceTest.cpp	(revision 0)
@@ -0,0 +1,150 @@
+
+/*
+ * 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 "SkCanvas.h"
+#include "SkRRect.h"
+#include "SkSurface.h"
+#include "Test.h"
+
+#if SK_SUPPORT_GPU
+#include "GrContextFactory.h"
+#else
+class GrContextFactory;
+class GrContext;
+#endif
+
+enum SurfaceType {
+    kRaster_SurfaceType,
+    kGpu_SurfaceType,
+    kPicture_SurfaceType
+};
+
+static SkSurface* createSurface(SurfaceType surfaceType, GrContext* context) {
+    static const SkImage::Info imageSpec = {
+        10,  // width
+        10,  // height
+        SkImage::kPMColor_ColorType,
+        SkImage::kPremul_AlphaType
+    };
+
+    switch (surfaceType) {
+    case kRaster_SurfaceType:
+        return SkSurface::NewRaster(imageSpec);
+    case kGpu_SurfaceType:
+#if SK_SUPPORT_GPU
+        SkASSERT(NULL != context);
+        return SkSurface::NewRenderTarget(context, imageSpec);
+#else
+        SkASSERT(0);
+#endif
+    case kPicture_SurfaceType:
+        return SkSurface::NewPicture(10, 10);
+    }
+    SkASSERT(0);
+    return NULL;
+}
+
+static void TestSurfaceCopyOnWrite(skiatest::Reporter* reporter, SurfaceType surfaceType,
+                                   GrContext* context) {
+    // Verify that the right canvas commands trigger a copy on write
+    SkSurface* surface = createSurface(surfaceType, context);
+    SkAutoTUnref<SkSurface> aur_surface(surface);
+    SkCanvas* canvas = surface->getCanvas();
+
+    const SkRect testRect =
+        SkRect::MakeXYWH(SkIntToScalar(0), SkIntToScalar(0),
+                         SkIntToScalar(4), SkIntToScalar(5));
+    SkMatrix testMatrix;
+    testMatrix.reset();
+    testMatrix.setScale(SkIntToScalar(2), SkIntToScalar(3));
+
+    SkPath testPath;
+    testPath.addRect(SkRect::MakeXYWH(SkIntToScalar(0), SkIntToScalar(0),
+                                      SkIntToScalar(2), SkIntToScalar(1)));
+
+    const SkIRect testIRect = SkIRect::MakeXYWH(0, 0, 2, 1);
+
+    SkRegion testRegion;
+    testRegion.setRect(testIRect);
+
+
+    const SkColor testColor = 0x01020304;
+    const SkPaint testPaint;
+    const SkPoint testPoints[3] = {
+        {SkIntToScalar(0), SkIntToScalar(0)},
+        {SkIntToScalar(2), SkIntToScalar(1)},
+        {SkIntToScalar(0), SkIntToScalar(2)}
+    };
+    const size_t testPointCount = 3;
+
+    SkBitmap testBitmap;
+    testBitmap.setConfig(SkBitmap::kARGB_8888_Config, 10, 10);
+    testBitmap.allocPixels();
+
+    SkRRect testRRect;
+    testRRect.setRectXY(testRect, SK_Scalar1, SK_Scalar1);
+
+    SkString testText("Hello World");
+    const SkPoint testPoints2[] = {
+        { SkIntToScalar(0), SkIntToScalar(1) },
+        { SkIntToScalar(1), SkIntToScalar(1) },
+        { SkIntToScalar(2), SkIntToScalar(1) },
+        { SkIntToScalar(3), SkIntToScalar(1) },
+        { SkIntToScalar(4), SkIntToScalar(1) },
+        { SkIntToScalar(5), SkIntToScalar(1) },
+        { SkIntToScalar(6), SkIntToScalar(1) },
+        { SkIntToScalar(7), SkIntToScalar(1) },
+        { SkIntToScalar(8), SkIntToScalar(1) },
+        { SkIntToScalar(9), SkIntToScalar(1) },
+        { SkIntToScalar(10), SkIntToScalar(1) },
+    };
+
+#define EXPECT_COPY_ON_WRITE(command)                               \
+    {                                                               \
+        SkImage* imageBefore = surface->newImageShapshot();         \
+        SkAutoTUnref<SkImage> aur_before(imageBefore);              \
+        canvas-> command ;                                          \
+        SkImage* imageAfter = surface->newImageShapshot();          \
+        SkAutoTUnref<SkImage> aur_after(imageAfter);                \
+        REPORTER_ASSERT(reporter, imageBefore != imageAfter);       \
+    }
+
+    EXPECT_COPY_ON_WRITE(clear(testColor))
+    EXPECT_COPY_ON_WRITE(drawPaint(testPaint))
+    EXPECT_COPY_ON_WRITE(drawPoints(SkCanvas::kPoints_PointMode, testPointCount, testPoints, \
+        testPaint))
+    EXPECT_COPY_ON_WRITE(drawOval(testRect, testPaint))
+    EXPECT_COPY_ON_WRITE(drawRect(testRect, testPaint))
+    EXPECT_COPY_ON_WRITE(drawRRect(testRRect, testPaint))
+    EXPECT_COPY_ON_WRITE(drawPath(testPath, testPaint))
+    EXPECT_COPY_ON_WRITE(drawBitmap(testBitmap, 0, 0))
+    EXPECT_COPY_ON_WRITE(drawBitmapRect(testBitmap, NULL, testRect))
+    EXPECT_COPY_ON_WRITE(drawBitmapMatrix(testBitmap, testMatrix, NULL))
+    EXPECT_COPY_ON_WRITE(drawBitmapNine(testBitmap, testIRect, testRect, NULL))
+    EXPECT_COPY_ON_WRITE(drawSprite(testBitmap, 0, 0, NULL))
+    EXPECT_COPY_ON_WRITE(drawText(testText.c_str(), testText.size(), 0, 1, testPaint))
+    EXPECT_COPY_ON_WRITE(drawPosText(testText.c_str(), testText.size(), testPoints2, \
+        testPaint))
+    EXPECT_COPY_ON_WRITE(drawTextOnPath(testText.c_str(), testText.size(), testPath, NULL, \
+        testPaint))
+}
+
+static void TestSurface(skiatest::Reporter* reporter) {
+    TestSurfaceCopyOnWrite(reporter, kRaster_SurfaceType, NULL);
+    TestSurfaceCopyOnWrite(reporter, kPicture_SurfaceType, NULL);
+}
+
+static void TestSurfaceGpu(skiatest::Reporter* reporter, GrContextFactory* factory) {
+#if SK_SUPPORT_GPU
+    GrContext* context = factory->get(GrContextFactory::kNative_GLContextType);
+    TestSurfaceCopyOnWrite(reporter, kGpu_SurfaceType, context);
+#endif
+}
+
+#include "TestClassDef.h"
+DEFINE_TESTCLASS("Surface", SurfaceTestClass, TestSurface)
+DEFINE_GPUTESTCLASS("SurfaceGpu", SurfaceGpuTestClass, TestSurfaceGpu)