| // Copyright (c) 2012 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 SKIA_EXT_BITMAP_PLATFORM_DEVICE_WIN_H_ |
| #define SKIA_EXT_BITMAP_PLATFORM_DEVICE_WIN_H_ |
| |
| #include "base/compiler_specific.h" |
| #include "base/macros.h" |
| #include "skia/ext/platform_device.h" |
| #include "skia/ext/refptr.h" |
| |
| namespace skia { |
| |
| // A device is basically a wrapper around SkBitmap that provides a surface for |
| // SkCanvas to draw into. Our device provides a surface Windows can also write |
| // to. BitmapPlatformDevice creates a bitmap using CreateDIBSection() in a |
| // format that Skia supports and can then use this to draw ClearType into, etc. |
| // This pixel data is provided to the bitmap that the device contains so that it |
| // can be shared. |
| class SK_API BitmapPlatformDevice : public SkBitmapDevice, public PlatformDevice { |
| public: |
| // Factory function. is_opaque should be set if the caller knows the bitmap |
| // will be completely opaque and allows some optimizations. |
| // |
| // The |shared_section| parameter is optional (pass NULL for default |
| // behavior). If |shared_section| is non-null, then it must be a handle to a |
| // file-mapping object returned by CreateFileMapping. See CreateDIBSection |
| // for details. If |shared_section| is null, the bitmap backing store is not |
| // initialized. |
| static BitmapPlatformDevice* Create(int width, int height, |
| bool is_opaque, HANDLE shared_section, |
| bool do_clear = false); |
| |
| // Create a BitmapPlatformDevice with no shared section. The bitmap is not |
| // initialized to 0. |
| static BitmapPlatformDevice* Create(int width, int height, bool is_opaque); |
| |
| ~BitmapPlatformDevice() override; |
| |
| // PlatformDevice overrides |
| // Retrieves the bitmap DC, which is the memory DC for our bitmap data. The |
| // bitmap DC is lazy created. |
| PlatformSurface BeginPlatformPaint() override; |
| void EndPlatformPaint() override; |
| |
| // Loads the given transform and clipping region into the HDC. This is |
| // overridden from SkBaseDevice. |
| void setMatrixClip(const SkMatrix& transform, |
| const SkRegion& region, |
| const SkClipStack&) override; |
| |
| void DrawToHDC(HDC dc, int x, int y, const RECT* src_rect) override; |
| |
| protected: |
| // Flushes the Windows device context so that the pixel data can be accessed |
| // directly by Skia. Overridden from SkBaseDevice, this is called when Skia |
| // starts accessing pixel data. |
| const SkBitmap& onAccessBitmap() override; |
| |
| SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) override; |
| |
| private: |
| // Private constructor. |
| BitmapPlatformDevice(HBITMAP hbitmap, const SkBitmap& bitmap); |
| |
| // Bitmap into which the drawing will be done. This bitmap not owned by this |
| // class, but by the BitmapPlatformPixelRef inside the device's SkBitmap. |
| // It's only stored here in order to lazy-create the DC (below). |
| HBITMAP hbitmap_; |
| |
| // Previous bitmap held by the DC. This will be selected back before the |
| // DC is destroyed. |
| HBITMAP old_hbitmap_; |
| |
| // Lazily-created DC used to draw into the bitmap; see GetBitmapDC(). |
| HDC hdc_; |
| |
| // True when there is a transform or clip that has not been set to the |
| // context. The context is retrieved for every text operation, and the |
| // transform and clip do not change as much. We can save time by not loading |
| // the clip and transform for every one. |
| bool config_dirty_; |
| |
| // Translation assigned to the context: we need to keep track of this |
| // separately so it can be updated even if the context isn't created yet. |
| SkMatrix transform_; |
| |
| // The current clipping region. |
| SkRegion clip_region_; |
| |
| // Create/destroy hdc_, which is the memory DC for our bitmap data. |
| HDC GetBitmapDC(); |
| void ReleaseBitmapDC(); |
| bool IsBitmapDCCreated() const; |
| |
| // Sets the transform and clip operations. This will not update the DC, |
| // but will mark the config as dirty. The next call of LoadConfig will |
| // pick up these changes. |
| void SetMatrixClip(const SkMatrix& transform, const SkRegion& region); |
| |
| // Loads the current transform and clip into the context. Can be called even |
| // when |hbitmap_| is NULL (will be a NOP). |
| void LoadConfig(); |
| |
| #ifdef SK_DEBUG |
| int begin_paint_count_; |
| #endif |
| |
| DISALLOW_COPY_AND_ASSIGN(BitmapPlatformDevice); |
| }; |
| |
| } // namespace skia |
| |
| #endif // SKIA_EXT_BITMAP_PLATFORM_DEVICE_WIN_H_ |