Add ability to build a canvas with a target scale factor.
This allows ExtractBitmap() to return an ImageSkiaRep.
This simplifies code around using intermediate bitmaps a lot.
BUG=131475
TEST=Compiles
R=oshima,sky
TBR=sadrul
Review URL: https://chromiumcodereview.appspot.com/10562027
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@144489 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/ui/gfx/canvas.h b/ui/gfx/canvas.h
index 67807746..e7af1785 100644
--- a/ui/gfx/canvas.h
+++ b/ui/gfx/canvas.h
@@ -98,21 +98,44 @@
NO_SUBPIXEL_RENDERING = 1 << 13,
};
- // Creates an empty canvas.
+ // Creates an empty canvas with scale factor of 1x.
Canvas();
+ // Creates canvas with provided DIP |size| and a scale factor of 1x.
// If this canvas is not opaque, it's explicitly cleared to transparent before
// being returned.
+ // TODO(pkotwicz): Remove this constructor.
Canvas(const gfx::Size& size, bool is_opaque);
- // Constructs a canvas the size of the provided |bitmap|, and draws the
- // bitmap into it.
- Canvas(const SkBitmap& bitmap, bool is_opaque);
+ // Creates canvas with provided DIP |size| and |scale_factor|.
+ // If this canvas is not opaque, it's explicitly cleared to transparent before
+ // being returned.
+ Canvas(const gfx::Size& size,
+ ui::ScaleFactor scale_factor,
+ bool is_opaque);
- explicit Canvas(SkCanvas* canvas);
+ // Constructs a canvas with the size and the scale factor of the
+ // provided |image_rep|, and draws the |image_rep| into it.
+ Canvas(const gfx::ImageSkiaRep& image_rep, bool is_opaque);
+
+ // Sets scale factor to |scale_factor|.
+ // Only scales canvas if |scale_canvas| is true.
+ Canvas(SkCanvas* canvas,
+ ui::ScaleFactor scale_factor,
+ bool scale_canvas);
virtual ~Canvas();
+ // Recreates the backing platform canvas with DIP |size| and |scale_factor|.
+ // If the canvas is not opaque, it is explicitly cleared.
+ // This method is public so that canvas_skia_paint can recreate the platform
+ // canvas after having initialized the canvas.
+ // TODO(pkotwicz): Push the scale factor into skia::PlatformCanvas such that
+ // this method can be private.
+ void RecreateBackingCanvas(const gfx::Size& size,
+ ui::ScaleFactor scale_factor,
+ bool is_opaque);
+
// Compute the size required to draw some text with the provided font.
// Attempts to fit the text with the provided width and height. Increases
// height and then width as needed to make the text fit. This method
@@ -152,8 +175,13 @@
int flags);
// Extracts a bitmap from the contents of this canvas.
+ // TODO(pkotwicz): Remove ExtractBitmap once all callers use
+ // ExtractImageSkiaRep instead.
SkBitmap ExtractBitmap() const;
+ // Extracts an ImageSkiaRep from the contents of this canvas.
+ gfx::ImageSkiaRep ExtractImageSkiaRep() const;
+
// Draws a dashed rectangle of the specified color.
void DrawDashedRect(const gfx::Rect& rect, SkColor color);
@@ -351,12 +379,19 @@
skia::PlatformCanvas* platform_canvas() const { return owned_canvas_.get(); }
SkCanvas* sk_canvas() const { return canvas_; }
+ ui::ScaleFactor scale_factor() const { return scale_factor_; }
private:
// Test whether the provided rectangle intersects the current clip rect.
bool IntersectsClipRectInt(int x, int y, int w, int h);
bool IntersectsClipRect(const gfx::Rect& rect);
+ // Sets the canvas' scale factor to |scale_factor|. This affects
+ // the scale factor at which drawing bitmaps occurs and the scale factor of
+ // the image rep returned by Canvas::ExtractImageSkiaRep().
+ // If |scale_canvas| is true, scales the canvas by |scale_factor|.
+ void ApplyScaleFactor(ui::ScaleFactor scale_factor, bool scale_canvas);
+
// Returns the bitmap whose density best matches the current canvas scale.
// Returns a null bitmap if |image| contains no bitmaps.
// |bitmap_scale_factor| is set to the scale factor of the returned bitmap.
@@ -384,6 +419,15 @@
scoped_ptr<skia::PlatformCanvas> owned_canvas_;
SkCanvas* canvas_;
+ // True if the scale factor scales the canvas and the inverse
+ // canvas scale should be applied when the destructor is called.
+ bool scale_factor_scales_canvas_;
+
+ // The device scale factor at which drawing on this canvas occurs.
+ // An additional scale can be applied via Canvas::Scale(). However,
+ // Canvas::Scale() does not affect |scale_factor_|.
+ ui::ScaleFactor scale_factor_;
+
DISALLOW_COPY_AND_ASSIGN(Canvas);
};
