ChromeCanvas->gfx::Canvas

app/gfx/chrome_canvas.h

-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef APP_GFX_CHROME_CANVAS_H_
-#define APP_GFX_CHROME_CANVAS_H_
-
-#if defined(OS_WIN)
-#include <windows.h>
-#endif
-
-#include <string>
-
-#include "base/basictypes.h"
-#include "skia/ext/platform_canvas.h"
-
-namespace gfx {
-class Font;
-class Rect;
-}
-
-#if defined(OS_LINUX)
-typedef struct _cairo cairo_t;
-#endif
-
-// ChromeCanvas is the SkCanvas used by Views for all painting. It
-// provides a handful of methods for the common operations used throughout
-// Views. With few exceptions, you should NOT create a ChromeCanvas directly,
-// rather one will be passed to you via the various paint methods in view.
-//
-// All methods that take integer arguments (as is used throughout views)
-// end with Int. If you need to use methods provided by the superclass
-// you'll need to do a conversion. In particular you'll need to use
-// macro SkIntToScalar(xxx), or if converting from a scalar to an integer
-// SkScalarRound.
-//
-// A handful of methods in this class are overloaded providing an additional
-// argument of type SkPorterDuff::Mode. SkPorterDuff::Mode specifies how the
-// source and destination colors are combined. Unless otherwise specified,
-// the variant that does not take a SkPorterDuff::Mode uses a transfer mode
-// of kSrcOver_Mode.
-class ChromeCanvas : public skia::PlatformCanvas {
- 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,
-  };
-
-  // Creates an empty ChromeCanvas. Callers must use initialize before using
-  // the canvas.
-  ChromeCanvas();
-
-  ChromeCanvas(int width, int height, bool is_opaque);
-
-  virtual ~ChromeCanvas();
-
-  // Retrieves the clip rectangle and sets it in the specified rectangle if any.
-  // Returns true if the clip rect is non-empty.
-  bool GetClipRect(gfx::Rect* clip_rect);
-
-  // Wrapper function that takes integer arguments.
-  // Returns true if the clip is non-empty.
-  // See clipRect for specifics.
-  bool ClipRectInt(int x, int y, int w, int h);
-
-  // Test whether the provided rectangle intersects the current clip rect.
-  bool IntersectsClipRectInt(int x, int y, int w, int h);
-
-  // Wrapper function that takes integer arguments.
-  // See translate() for specifics.
-  void TranslateInt(int x, int y);
-
-  // Wrapper function that takes integer arguments.
-  // See scale() for specifics.
-  void ScaleInt(int x, int y);
-
-  // Fills the given rectangle with the given paint's parameters.
-  void FillRectInt(int x, int y, int w, int h, const SkPaint& paint);
-
-  // Fills the specified region with the specified color using a transfer
-  // mode of SkPorterDuff::kSrcOver_Mode.
-  void FillRectInt(const SkColor& color, int x, int y, int w, int h);
-
-  // Draws a single pixel rect in the specified region with the specified
-  // color, using a transfer mode of SkPorterDuff::kSrcOver_Mode.
-  //
-  // NOTE: if you need a single pixel line, use DraLineInt.
-  void DrawRectInt(const SkColor& color, int x, int y, int w, int h);
-
-  // 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 DraLineInt.
-  void DrawRectInt(const SkColor& color, int x, int y, int w, int h,
-                   SkPorterDuff::Mode mode);
-
-  // Draws a single pixel line with the specified color.
-  void DrawLineInt(const SkColor& color, int x1, int y1, int x2, int y2);
-
-  // Draws a bitmap with the origin at the specified location. The upper left
-  // corner of the bitmap is rendered at the specified location.
-  void DrawBitmapInt(const SkBitmap& bitmap, int x, int y);
-
-  // 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.
-  void DrawBitmapInt(const SkBitmap& bitmap, int x, int y,
-                     const SkPaint& paint);
-
-  // 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.
-  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);
-  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);
-
-  // 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.
-  void DrawStringInt(const std::wstring& text, const gfx::Font& font,
-                     const SkColor& color, int x, int y, int w, int h);
-
-  // 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.
-  void DrawStringInt(const std::wstring& text, const gfx::Font& font,
-                     const SkColor& color, int x, int y, int w, int h,
-                     int flags);
-
-#ifdef OS_WIN  // Only implemented on Windows for now.
-  // Draws text with a 1-pixel halo around it of the given color. It allows
-  // ClearType to be drawn to an otherwise transparenct bitmap for drag images.
-  // Drag images have only 1-bit of transparency, so we don't do any fancy
-  // blurring.
-  void DrawStringWithHalo(const std::wstring& text, const gfx::Font& font,
-                          const SkColor& text_color, const SkColor& halo_color,
-                          int x, int y, int w, int h, int flags);
-#endif
-
-  // Draws a dotted gray rectangle used for focus purposes.
-  void DrawFocusRect(int x, int y, int width, int height);
-
-  // Tiles the image in the specified region.
-  void TileImageInt(const SkBitmap& bitmap, int x, int y, int w, int h);
-  void TileImageInt(const SkBitmap& bitmap, int src_x, int src_y,
-                    int dest_x, int dest_y, int w, int h);
-
-  // Extracts a bitmap from the contents of this canvas.
-  SkBitmap ExtractBitmap();
-
-#if defined(OS_LINUX)
-  // Applies current matrix on the canvas to the cairo context. This should be
-  // invoked anytime you plan on drawing directly to the cairo context. Be
-  // sure and set the matrix back to the identity when done.
-  void ApplySkiaMatrixToCairoContext(cairo_t* cr);
-#endif
-
-  // 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
-  // supports multiple lines.
-  static void SizeStringInt(const std::wstring& test, const gfx::Font& font,
-                            int *width, int* height, int flags);
-
- private:
-#if defined(OS_WIN)
-  // 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.
-  void DrawStringInt(const std::wstring& text, HFONT font,
-                     const SkColor& color, int x, int y, int w, int h,
-                     int flags);
-#endif
-
-  DISALLOW_EVIL_CONSTRUCTORS(ChromeCanvas);
-};
-
-#if defined(OS_WIN) || defined(OS_LINUX)
-typedef skia::CanvasPaintT<ChromeCanvas> ChromeCanvasPaint;
-#endif
-
-#endif  // APP_GFX_CHROME_CANVAS_H_