Make copySurface work for texture dsts, return a bool, & add unit test.

tests/CopySurfaceTest.cpp

Index: tests/CopySurfaceTest.cpp
diff --git a/tests/CopySurfaceTest.cpp b/tests/CopySurfaceTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..4b6453714334e112eb6cf3a7e2ab7536fc945d1a
--- /dev/null
+++ b/tests/CopySurfaceTest.cpp
@@ -0,0 +1,163 @@
+/*
+ * 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 <initializer_list>
+#include "Test.h"
+
+#if SK_SUPPORT_GPU
+#include "GrContext.h"
+#include "GrTexture.h"
+#include "GrTextureProvider.h"
+
+#include "SkUtils.h"
+
+DEF_GPUTEST_FOR_RENDERING_CONTEXTS(CopySurface, reporter, context) {
+    static const int kW = 10;
+    static const int kH = 10;
+    static const size_t kRowBytes = sizeof(uint32_t) * kW;
+
+    GrSurfaceDesc baseDesc;
+    baseDesc.fConfig = kRGBA_8888_GrPixelConfig;
+    baseDesc.fWidth = kW;
+    baseDesc.fHeight = kH;
+
+    SkAutoTMalloc<uint32_t> srcPixels(kW * kH);
+    for (int i = 0; i < kW * kH; ++i) {
+        srcPixels.get()[i] = i;
+    }
+
+    SkAutoTMalloc<uint32_t> dstPixels(kW * kH);
+    for (int i = 0; i < kW * kH; ++i) {
+        dstPixels.get()[i] = ~i;
+    }
+
+    static const SkIRect kSrcRects[] {
+        { 0,  0, kW  , kH  },
+        {-1, -1, kW+1, kH+1},
+        { 1,  1, kW-1, kH-1},
+        { 5,  5, 6   , 6   },
+    };
+
+    static const SkIPoint kDstPoints[] {
+        { 0   ,  0   },
+        { 1   ,  1   },
+        { kW/2,  kH/4},
+        { kW-1,  kH-1},
+        { kW  ,  kH  },
+        { kW+1,  kH+2},
+        {-1   , -1   },
+    };
+
+    SkAutoTMalloc<uint32_t> read(kW * kH);
+
+    for (auto sOrigin : {kBottomLeft_GrSurfaceOrigin, kTopLeft_GrSurfaceOrigin}) {
+        for (auto dOrigin : {kBottomLeft_GrSurfaceOrigin, kTopLeft_GrSurfaceOrigin}) {
+            for (auto sFlags: {kRenderTarget_GrSurfaceFlag, kNone_GrSurfaceFlags}) {
+                for (auto dFlags: {kRenderTarget_GrSurfaceFlag, kNone_GrSurfaceFlags}) {
+                    for (auto srcRect : kSrcRects) {
+                        for (auto dstPoint : kDstPoints) {
+                            GrSurfaceDesc srcDesc = baseDesc;
+                            srcDesc.fOrigin = sOrigin;
+                            srcDesc.fFlags = sFlags;
+                            GrSurfaceDesc dstDesc = baseDesc;
+                            dstDesc.fOrigin = dOrigin;
+                            dstDesc.fFlags = dFlags;
+
+                            SkAutoTUnref<GrTexture> src(
+                                context->textureProvider()->createTexture(srcDesc, false,
+                                                                          srcPixels.get(),
+                                                                          kRowBytes));
+                            SkAutoTUnref<GrTexture> dst(
+                                context->textureProvider()->createTexture(dstDesc, false,
+                                                                          dstPixels.get(),
+                                                                          kRowBytes));
+                            if (!src || !dst) {
+                                ERRORF(reporter,
+                                       "Could not create surfaces for copy surface test.");
+                                continue;
+                            }
+
+                            bool result = context->copySurface(dst, src, srcRect, dstPoint);
+
+                            bool expectedResult = true;
+                            SkIPoint dstOffset = { dstPoint.fX - srcRect.fLeft,
+                                                   dstPoint.fY - srcRect.fTop };
+                            SkIRect copiedDstRect = SkIRect::MakeXYWH(dstPoint.fX,
+                                                                      dstPoint.fY,
+                                                                      srcRect.width(),
+                                                                      srcRect.height());
+
+                            SkIRect copiedSrcRect;
+                            if (!copiedSrcRect.intersect(srcRect, SkIRect::MakeWH(kW, kH))) {
+                                expectedResult = false;
+                            } else {
+                                // If the src rect was clipped, apply same clipping to each side of
+                                // copied dst rect.
+                                copiedDstRect.fLeft += copiedSrcRect.fLeft - srcRect.fLeft;
+                                copiedDstRect.fTop += copiedSrcRect.fTop - srcRect.fTop;
+                                copiedDstRect.fRight -= copiedSrcRect.fRight - srcRect.fRight;
+                                copiedDstRect.fBottom -= copiedSrcRect.fBottom - srcRect.fBottom;
+                            }
+                            if (copiedDstRect.isEmpty() ||
+                                !copiedDstRect.intersect(SkIRect::MakeWH(kW, kH))) {
+                                expectedResult = false;
+                            }
+                            // To make the copied src rect correct we would apply any dst clipping
+                            // back to the src rect, but we don't use it again so don't bother.
+                            if (expectedResult != result) {
+                                ERRORF(reporter, "Expected return value %d from copySurface, got "
+                                       "%d.", expectedResult, result);
+                                continue;
+                            }
+
+                            if (!expectedResult || !result) {
+                                continue;
+                            }
+
+                            sk_memset32(read.get(), 0, kW * kH);
+                            if (!dst->readPixels(0, 0, kW, kH, baseDesc.fConfig, read.get(),
+                                                 kRowBytes)) {
+                                ERRORF(reporter, "Error calling readPixels");
+                                continue;
+                            }
+
+                            bool abort = false;
+                            // Validate that pixels inside copiedDstRect received the correct value
+                            // from src and that those outside were not modified.
+                            for (int y = 0; y < kH && !abort; ++y) {
+                                for (int x = 0; x < kW; ++x) {
+                                    uint32_t r = read.get()[y * kW + x];
+                                    if (copiedDstRect.contains(x, y)) {
+                                        int sx = x - dstOffset.fX;
+                                        int sy = y - dstOffset.fY;
+                                        uint32_t s = srcPixels.get()[sy * kW + sx];
+                                        if (s != r) {
+                                            ERRORF(reporter, "Expected dst %d,%d to contain "
+                                                   "0x%08x copied from src location %d,%d. Got "
+                                                   "0x%08x", x, y, s, sx, sy, r);
+                                            abort = true;
+                                            break;
+                                        }
+                                    } else {
+                                        uint32_t d = dstPixels.get()[y * kW + x];
+                                        if (d != r) {
+                                            ERRORF(reporter, "Expected dst %d,%d to be unmodified ("
+                                                   "0x%08x). Got 0x%08x", x, y, d, r);
+                                            abort = true;
+                                            break;
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+#endif