add peekPixels to canvas

gm/aaclip.cpp

Index: gm/aaclip.cpp
diff --git a/gm/aaclip.cpp b/gm/aaclip.cpp
index ec29a4f896f324a87d3f8d7e9b825d6210b17885..537da07386d3b75818cb3951244976ebf0c9eed5 100644
--- a/gm/aaclip.cpp
+++ b/gm/aaclip.cpp
@@ -8,6 +8,7 @@
 #include "gm.h"
 #include "SkCanvas.h"
 #include "SkPath.h"
+#include "SkSurface.h"
 
 static void test_quadstroke(SkCanvas* canvas) {
     SkPath path;
@@ -122,27 +123,28 @@ static void test_grad(SkCanvas* canvas) {
     canvas->drawPaint(p);
 }
 
-static SkCanvas* MakeCanvas(const SkIRect& bounds) {
-    SkBitmap bm;
-    bm.allocN32Pixels(bounds.width(), bounds.height());
-    bm.eraseColor(SK_ColorTRANSPARENT);
-
-    SkCanvas* canvas = new SkCanvas(bm);
-    canvas->translate(-SkIntToScalar(bounds.fLeft), -SkIntToScalar(bounds.fTop));
-    return canvas;
+static SkSurface* MakeSurface(const SkIRect& bounds) {
+    SkImageInfo info = SkImageInfo::MakeN32Premul(bounds.width(),
+                                                  bounds.height());
+    SkSurface* surface = SkSurface::NewRaster(info);
+    surface->getCanvas()->clear(0);
+    surface->getCanvas()->translate(-SkIntToScalar(bounds.fLeft),
+                                    -SkIntToScalar(bounds.fTop));
+    return surface;
 }
 
+static void compare(SkSurface* a, SkSurface* b) {
 #ifdef SK_DEBUG
-static void GetBitmap(const SkCanvas* canvas, SkBitmap* bm) {
-    *bm = canvas->getDevice()->accessBitmap(false);
-}
-#endif
+    SkImageInfo infoa, infob;
+    size_t rowBytesa, rowBytesb;
+
+    const void* pa = a->peekPixels(&infoa, &rowBytesa);
+    const void* pb = b->peekPixels(&infob, &rowBytesb);
+    SkASSERT(pa && pb);
 
-static void compare_canvas(const SkCanvas* a, const SkCanvas* b) {
-#ifdef SK_DEBUG
     SkBitmap bma, bmb;
-    GetBitmap(a, &bma);
-    GetBitmap(b, &bmb);
+    bma.installPixels(infoa, const_cast<void*>(pa), rowBytesa, NULL, NULL);
+    bmb.installPixels(infob, const_cast<void*>(pb), rowBytesb, NULL, NULL);
 
     SkASSERT(bma.width() == bmb.width());
     SkASSERT(bma.height() == bmb.height());
@@ -175,13 +177,13 @@ static void test_maskFromPath(const SkPath& path) {
     SkPaint paint;
     paint.setAntiAlias(true);
 
-    SkAutoTUnref<SkCanvas> path_canvas(MakeCanvas(bounds));
-    path_canvas->drawPath(path, paint);
+    SkAutoTUnref<SkSurface> path_surface(MakeSurface(bounds));
+    path_surface->getCanvas()->drawPath(path, paint);
 
-    SkAutoTUnref<SkCanvas> rect_canvas(MakeCanvas(bounds));
-    drawRectAsPath(rect_canvas, path.getBounds(), paint);
+    SkAutoTUnref<SkSurface> rect_surface(MakeSurface(bounds));
+    drawRectAsPath(rect_surface->getCanvas(), path.getBounds(), paint);
 
-    compare_canvas(path_canvas, rect_canvas);
+    compare(path_surface, rect_surface);
 }
 
 static void test_mask() {
@@ -285,7 +287,7 @@ protected:
         if (false) {
             test_grad(canvas); return;
         }
-        if (false) { // avoid bit rot, suppress warning
+        if (true) { // avoid bit rot, suppress warning
             test_mask();
         }