Ensure that the source rect used for the the raster cache replacement…

… is the same as the size of the N32Premul surface. (flutter#3889)

Also adds debug printers for SkRect and SkPoint.

flow/debug_print.cc

@@ -53,6 +53,17 @@ std::ostream& operator<<(std::ostream& os, const SkVector4& v) {
   return os;
 }
 
+std::ostream& operator<<(std::ostream& os, const SkRect& r) {
+  os << "LTRB: " << r.fLeft << ", " << r.fTop << ", " << r.fRight << ", "
+     << r.fBottom;
+  return os;
+}
+
+std::ostream& operator<<(std::ostream& os, const SkPoint& r) {
+  os << "XY: " << r.fX << ", " << r.fY;
+  return os;
+}
+
 std::ostream& operator<<(std::ostream& os, const flow::RasterCacheKey& k) {
   os << "Picture: " << k.picture_id() << " Scale: " << k.scale_key().width()
      << ", " << k.scale_key().height();

flow/debug_print.h

@@ -20,5 +20,7 @@ DEF_PRINTER(SkMatrix);
 DEF_PRINTER(SkMatrix44);
 DEF_PRINTER(SkVector3);
 DEF_PRINTER(SkVector4);
+DEF_PRINTER(SkRect);
+DEF_PRINTER(SkPoint);
 
 #endif  // FLUTTER_FLOW_DEBUG_PRINT_H_

flow/raster_cache.cc

@@ -75,14 +75,17 @@ RasterCacheResult RasterizePicture(SkPicture* picture,
   TRACE_EVENT0("flutter", "RasterCachePopulate");
 
   const SkVector3& scale = matrix.scale();
-  SkRect logical_rect = picture->cullRect();
 
-  const SkImageInfo image_info = SkImageInfo::MakeN32Premul(
-      std::ceil(logical_rect.width() * std::abs(scale.x())),  // physical width
-      std::ceil(logical_rect.height() *
-                std::abs(scale.y())),  // physical height
-      nullptr                          // colorspace
-      );
+  const SkRect logical_rect = picture->cullRect();
+  const SkRect physical_rect =
+      SkRect::MakeWH(std::ceil(std::labs(logical_rect.width() * scale.x())),
+                     std::ceil(std::labs(logical_rect.height() * scale.y())));
+
+  const SkImageInfo image_info =
+      SkImageInfo::MakeN32Premul(physical_rect.width(),   // physical width
+                                 physical_rect.height(),  // physical height
+                                 nullptr                  // colorspace
+                                 );
 
   sk_sp<SkSurface> surface =
       context
@@ -107,10 +110,8 @@ RasterCacheResult RasterizePicture(SkPicture* picture,
 
   return {
       surface->makeImageSnapshot(),  // image
-      SkRect::MakeWH(
-          logical_rect.width() * std::abs(scale.x()),
-          logical_rect.height() * std::abs(scale.y())),  // source rect
-      logical_rect                                       // destination rect
+      physical_rect,                 // source rect
+      logical_rect                   // destination rect
   };
 }