ui/gfx: Make gfx::Canvas inherit from gfx::CanvasSkia.

ui/gfx/canvas.h

Index: ui/gfx/canvas.h
diff --git a/ui/gfx/canvas.h b/ui/gfx/canvas.h
index 76926059fcdd66a5c565df62054232883a92df15..4dbc24dc128c70abb37fc3be4997fbb126f9a5e1 100644
--- a/ui/gfx/canvas.h
+++ b/ui/gfx/canvas.h
@@ -6,215 +6,18 @@
 #define UI_GFX_CANVAS_H_
 #pragma once
 
-#include <string>
-
-#include "base/string16.h"
-// TODO(beng): remove these includes when we no longer depend on SkTypes.
-#include "third_party/skia/include/core/SkColor.h"
-#include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/base/ui_export.h"
-#include "ui/gfx/native_widget_types.h"
-
-class SkCanvas;
-
-namespace ui {
-class Transform;
-}
+#include "ui/gfx/canvas_skia.h"
 
 namespace gfx {
 
-class Brush;
-class CanvasSkia;
-class Font;
-class Point;
-class Rect;
-class Size;
-
-// TODO(beng): documentation.
-class UI_EXPORT Canvas {
+class UI_EXPORT Canvas : public CanvasSkia {

[Alexei Svitkine (slow), 2012/03/06 17:44:51]

Please add a comment explaining that this is temporary and that the goal is to
rename CanvasSkia to Canvas.

[tfarina, 2012/03/06 18:05:30]

Done.

  public:
-  // Specifies the alignment for text rendered with the DrawStringInt method.
-  enum {
-    TEXT_ALIGN_LEFT = 1,
-    TEXT_ALIGN_CENTER = 2,
-    TEXT_ALIGN_RIGHT = 4,
-    TEXT_VALIGN_TOP = 8,
-    TEXT_VALIGN_MIDDLE = 16,
-    TEXT_VALIGN_BOTTOM = 32,
-
-    // Specifies the text consists of multiple lines.
-    MULTI_LINE = 64,
-
-    // By default DrawStringInt does not process the prefix ('&') character
-    // specially. That is, the string "&foo" is rendered as "&foo". When
-    // rendering text from a resource that uses the prefix character for
-    // mnemonics, the prefix should be processed and can be rendered as an
-    // underline (SHOW_PREFIX), or not rendered at all (HIDE_PREFIX).
-    SHOW_PREFIX = 128,
-    HIDE_PREFIX = 256,
-
-    // Prevent ellipsizing
-    NO_ELLIPSIS = 512,
-
-    // Specifies if words can be split by new lines.
-    // This only works with MULTI_LINE.
-    CHARACTER_BREAK = 1024,
-
-    // Instructs DrawStringInt() to render the text using RTL directionality.
-    // In most cases, passing this flag is not necessary because information
-    // about the text directionality is going to be embedded within the string
-    // in the form of special Unicode characters. However, we don't insert
-    // directionality characters into strings if the locale is LTR because some
-    // platforms (for example, an English Windows XP with no RTL fonts
-    // installed) don't support these characters. Thus, this flag should be
-    // used to render text using RTL directionality when the locale is LTR.
-    FORCE_RTL_DIRECTIONALITY = 2048,
-
-    // Similar to FORCE_RTL_DIRECTIONALITY, but left-to-right.
-    // See FORCE_RTL_DIRECTIONALITY for details.
-    FORCE_LTR_DIRECTIONALITY = 4096,
-  };
-
-  virtual ~Canvas() {}
-
-  // Saves a copy of the drawing state onto a stack, operating on this copy
-  // until a balanced call to Restore() is made.
-  virtual void Save() = 0;
-
-  // As with Save(), except draws to a layer that is blended with the canvas
-  // at the specified alpha once Restore() is called.
-  // |layer_bounds| are the bounds of the layer relative to the current
-  // transform.
-  virtual void SaveLayerAlpha(uint8 alpha) = 0;
-  virtual void SaveLayerAlpha(uint8 alpha, const gfx::Rect& layer_bounds) = 0;
-
-  // Restores the drawing state after a call to Save*(). It is an error to
-  // call Restore() more times than Save*().
-  virtual void Restore() = 0;
-
-  // Returns true if the clip is non-empty.
-  virtual bool ClipRect(const gfx::Rect& rect) = 0;
-
-  virtual void Translate(const gfx::Point& point) = 0;
-
-  virtual void Scale(int x_scale, int y_scale) = 0;
-
-  // Fills |rect| with |color| using a transfer mode of
-  // SkXfermode::kSrcOver_Mode.
-  virtual void FillRect(const gfx::Rect& rect, const SkColor& color) = 0;
-
-  // Fills |rect| with the specified |color| and |mode|.
-  virtual void FillRect(const gfx::Rect& rect,
-                        const SkColor& color,
-                        SkXfermode::Mode mode) = 0;
-
-  // Fills |rect| with the specified |brush|.
-  virtual void FillRect(const gfx::Rect& rect, const gfx::Brush* brush) = 0;
-
-  // Draws a single pixel rect in the specified region with the specified
-  // color, using a transfer mode of SkXfermode::kSrcOver_Mode.
-  //
-  // NOTE: if you need a single pixel line, use DrawLine.
-  virtual void DrawRect(const gfx::Rect& rect, const SkColor& color) = 0;
-
-  // Draws a single pixel rect in the specified region with the specified
-  // color and transfer mode.
-  //
-  // NOTE: if you need a single pixel line, use DrawLine.
-  virtual void DrawRect(const gfx::Rect& rect,
-                        const SkColor& color,
-                        SkXfermode::Mode mode) = 0;
-
-  // Draws the given rectangle with the given paint's parameters.
-  virtual void DrawRect(const gfx::Rect& rect, const SkPaint& paint) = 0;
-
-  // Draws a single pixel line with the specified color.
-  virtual void DrawLine(const gfx::Point& p1,
-                        const gfx::Point& p2,
-                        const SkColor& color) = 0;
-
-  // Draws a bitmap with the origin at the specified location. The upper left
-  // corner of the bitmap is rendered at the specified location.
-  virtual void DrawBitmapInt(const SkBitmap& bitmap, int x, int y) = 0;
-
-  // Draws a bitmap with the origin at the specified location, using the
-  // specified paint. The upper left corner of the bitmap is rendered at the
-  // specified location.
-  virtual void DrawBitmapInt(const SkBitmap& bitmap,
-                             int x, int y,
-                             const SkPaint& paint) = 0;
-
-  // Draws a portion of a bitmap in the specified location. The src parameters
-  // correspond to the region of the bitmap to draw in the region defined
-  // by the dest coordinates.
-  //
-  // If the width or height of the source differs from that of the destination,
-  // the bitmap will be scaled. When scaling down, it is highly recommended
-  // that you call buildMipMap(false) on your bitmap to ensure that it has
-  // a mipmap, which will result in much higher-quality output. Set |filter|
-  // to use filtering for bitmaps, otherwise the nearest-neighbor algorithm
-  // is used for resampling.
-  //
-  // An optional custom SkPaint can be provided.
-  virtual void DrawBitmapInt(const SkBitmap& bitmap,
-                             int src_x, int src_y, int src_w, int src_h,
-                             int dest_x, int dest_y, int dest_w, int dest_h,
-                             bool filter) = 0;
-  virtual void DrawBitmapInt(const SkBitmap& bitmap,
-                             int src_x, int src_y, int src_w, int src_h,
-                             int dest_x, int dest_y, int dest_w, int dest_h,
-                             bool filter,
-                             const SkPaint& paint) = 0;
-
-  // Draws text with the specified color, font and location. The text is
-  // aligned to the left, vertically centered, clipped to the region. If the
-  // text is too big, it is truncated and '...' is added to the end.
-  virtual void DrawStringInt(const string16& text,
-                             const gfx::Font& font,
-                             const SkColor& color,
-                             int x, int y, int w, int h) = 0;
-  virtual void DrawStringInt(const string16& text,
-                             const gfx::Font& font,
-                             const SkColor& color,
-                             const gfx::Rect& display_rect) = 0;
-
-  // Draws text with the specified color, font and location. The last argument
-  // specifies flags for how the text should be rendered. It can be one of
-  // TEXT_ALIGN_CENTER, TEXT_ALIGN_RIGHT or TEXT_ALIGN_LEFT.
-  virtual void DrawStringInt(const string16& text,
-                             const gfx::Font& font,
-                             const SkColor& color,
-                             int x, int y, int w, int h,
-                             int flags) = 0;
-
-  // Draws a dotted gray rectangle used for focus purposes.
-  virtual void DrawFocusRect(const gfx::Rect& rect) = 0;
-
-  // Tiles the image in the specified region.
-  virtual void TileImageInt(const SkBitmap& bitmap,
-                            int x, int y, int w, int h) = 0;
-  virtual void TileImageInt(const SkBitmap& bitmap,
-                            int src_x, int src_y,
-                            int dest_x, int dest_y, int w, int h) = 0;
-
-  // Returns a native drawing context for platform specific drawing routines to
-  // use. Must be balanced by a call to EndPlatformPaint().
-  virtual gfx::NativeDrawingContext BeginPlatformPaint() = 0;
-
-  // Signifies the end of platform drawing using the native drawing context
-  // returned by BeginPlatformPaint().
-  virtual void EndPlatformPaint() = 0;
+  explicit Canvas(SkCanvas* canvas);
 
-  // Apply transformation on the canvas.
-  virtual void Transform(const ui::Transform& transform) = 0;
+  Canvas(const gfx::Size& size, bool is_opaque);
 
-  // TODO(beng): remove this once we don't need to use any skia-specific methods
-  //             through this interface.
-  // A quick and dirty way to obtain the underlying SkCanvas.
-  virtual CanvasSkia* AsCanvasSkia();
-  virtual const CanvasSkia* AsCanvasSkia() const;
-  virtual SkCanvas* GetSkCanvas();
-  virtual const SkCanvas* GetSkCanvas() const;
+  Canvas(const SkBitmap& bitmap, bool is_opaque);
 };
 
 }  // namespace gfx