Add SkSpecialImage & SkSpecialSurface classes

tests/SpecialSurfaceTest.cpp

Index: tests/SpecialSurfaceTest.cpp
diff --git a/tests/SpecialSurfaceTest.cpp b/tests/SpecialSurfaceTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..b1cbf680822939d0b42179256ee28a5ebb29f073
--- /dev/null
+++ b/tests/SpecialSurfaceTest.cpp
@@ -0,0 +1,115 @@
+/*
+* Copyright 2016 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 "SkSpecialImage.h"
+#include "SkSpecialSurface.h"
+#include "Test.h"
+
+#if SK_SUPPORT_GPU
+#include "GrContext.h"
+#include "SkGr.h"
+#endif
+
+class TestingSpecialSurfaceAccess {
+public:
+    static const SkIRect& Subset(const SkSpecialSurface* surf) {
+        return surf->subset();
+    }
+
+    static const SkIRect& Subset(const SkSpecialImage* img) {
+        return img->subset();
+    }
+};
+
+// Both 'kSmallerSize' and 'kFullSize' need to be a non-power-of-2 to exercise
+// the gpu's loose fit behavior
+static const int kSmallerSize = 10;
+static const int kPad = 5;
+static const int kFullSize = kSmallerSize + 2 * kPad;
+
+// Exercise the public API of SkSpecialSurface (e.g., getCanvas, newImageSnapshot)
+static void test_surface(SkSpecialSurface* surf, skiatest::Reporter* reporter, int offset) {
+
+    const SkIRect surfSubset = TestingSpecialSurfaceAccess::Subset(surf);
+    REPORTER_ASSERT(reporter, offset == surfSubset.fLeft);
+    REPORTER_ASSERT(reporter, offset == surfSubset.fTop);
+    REPORTER_ASSERT(reporter, kSmallerSize == surfSubset.width());
+    REPORTER_ASSERT(reporter, kSmallerSize == surfSubset.height());
+
+    SkCanvas* canvas = surf->getCanvas();
+    SkASSERT_RELEASE(canvas);
+
+    canvas->clear(SK_ColorRED);
+
+    SkAutoTUnref<SkSpecialImage> img(surf->newImageSnapshot());
+    REPORTER_ASSERT(reporter, img);
+
+    const SkIRect imgSubset = TestingSpecialSurfaceAccess::Subset(img);
+    REPORTER_ASSERT(reporter, surfSubset == imgSubset);
+
+    // the canvas was invalidated by the newImageSnapshot call
+    REPORTER_ASSERT(reporter, !surf->getCanvas());
+}
+
+DEF_TEST(SpecialSurface_Raster, reporter) {
+
+    SkImageInfo info = SkImageInfo::MakeN32(kSmallerSize, kSmallerSize, kOpaque_SkAlphaType);
+    SkAutoTUnref<SkSpecialSurface> surf(SkSpecialSurface::NewRaster(info));
+
+    test_surface(surf, reporter, 0);
+}
+
+DEF_TEST(SpecialSurface_Raster2, reporter) {
+
+    SkBitmap bm;
+    bm.allocN32Pixels(kFullSize, kFullSize, true);
+
+    const SkIRect subset = SkIRect::MakeXYWH(kPad, kPad, kSmallerSize, kSmallerSize);
+
+    SkAutoTUnref<SkSpecialSurface> surf(SkSpecialSurface::NewFromBitmap(subset, bm));
+
+    test_surface(surf, reporter, kPad);
+
+    // TODO: check that the clear didn't escape the active region
+}
+
+#if SK_SUPPORT_GPU
+
+DEF_GPUTEST_FOR_RENDERING_CONTEXTS(SpecialSurface_Gpu1, reporter, context) {
+    GrSurfaceDesc desc;
+    desc.fConfig = kSkia8888_GrPixelConfig;
+    desc.fFlags  = kRenderTarget_GrSurfaceFlag;
+    desc.fWidth  = kSmallerSize;
+    desc.fHeight = kSmallerSize;
+
+    SkAutoTUnref<SkSpecialSurface> surf(SkSpecialSurface::NewRenderTarget(context, desc));
+
+    test_surface(surf, reporter, 0);
+}
+
+// test the more flexible factory
+DEF_GPUTEST_FOR_RENDERING_CONTEXTS(SpecialSurface_Gpu2, reporter, context) {
+    GrSurfaceDesc desc;
+    desc.fConfig = kSkia8888_GrPixelConfig;
+    desc.fFlags = kRenderTarget_GrSurfaceFlag;
+    desc.fWidth = kFullSize;
+    desc.fHeight = kFullSize;
+
+    SkAutoTUnref<GrTexture> temp(context->textureProvider()->createApproxTexture(desc));
+    SkASSERT_RELEASE(temp);
+
+    const SkIRect subset = SkIRect::MakeXYWH(kPad, kPad, kSmallerSize, kSmallerSize);
+
+    SkAutoTUnref<SkSpecialSurface> surf(SkSpecialSurface::NewFromTexture(subset, temp));
+
+    test_surface(surf, reporter, kPad);
+
+    // TODO: check that the clear didn't escape the active region
+}
+
+#endif