Roll skia to 8cc209111876b7c78b5ec577c9221d8ed5e21024

skia/ext/bitmap_platform_device_win.h

-// 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/basictypes.h"
-#include "base/compiler_specific.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.
-//
-// The GDI bitmap created for drawing is actually owned by a
-// PlatformBitmapPixelRef, and stored in an SkBitmap via the normal skia
-// SkPixelRef refcounting mechanism. In this way, the GDI bitmap can outlive
-// the device created to draw into it. So it is safe to call accessBitmap() on
-// the device, and retain the returned SkBitmap.
-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);
-
-  virtual ~BitmapPlatformDevice();
-
-  // PlatformDevice overrides
-  // Retrieves the bitmap DC, which is the memory DC for our bitmap data. The
-  // bitmap DC is lazy created.
-  virtual PlatformSurface BeginPlatformPaint() override;
-  virtual void EndPlatformPaint() override;
-
-  // Loads the given transform and clipping region into the HDC. This is
-  // overridden from SkBaseDevice.
-  virtual 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.
-  virtual 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_