SkImagePriv.h revision 363e546ed626b6dbbc42f5db87b3594bc0b5944b 
1/*
2 * Copyright 2012 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#ifndef SkImagePriv_DEFINED
9#define SkImagePriv_DEFINED
10
11#include "SkBitmap.h"
12#include "SkImage.h"
13
14class SkPicture;
15
16extern SkBitmap::Config SkImageInfoToBitmapConfig(const SkImage::Info&,
17                                                  bool* isOpaque);
18
19extern int SkImageBytesPerPixel(SkImage::ColorType);
20
21extern bool SkBitmapToImageInfo(const SkBitmap&, SkImage::Info*);
22
23// Call this if you explicitly want to use/share this pixelRef in the image
24extern SkImage* SkNewImageFromPixelRef(const SkImage::Info&, SkPixelRef*,
25                                       size_t rowBytes);
26
27/**
28 *  Examines the bitmap to decide if it can share the existing pixelRef, or
29 *  if it needs to make a deep-copy of the pixels. The bitmap's pixelref will
30 *  be shared if either the bitmap is marked as immutable, or canSharePixelRef
31 *  is true.
32 *
33 *  If the bitmap's config cannot be converted into a corresponding
34 *  SkImage::Info, or the bitmap's pixels cannot be accessed, this will return
35 *  NULL.
36 */
37extern SkImage* SkNewImageFromBitmap(const SkBitmap&, bool canSharePixelRef);
38
39extern void SkImagePrivDrawPicture(SkCanvas*, SkPicture*,
40                                   SkScalar x, SkScalar y, const SkPaint*);
41
42/**
43 *  Return an SkImage whose contents are those of the specified picture. Note:
44 *  The picture itself is unmodified, and may continue to be used for recording
45 */
46extern SkImage* SkNewImageFromPicture(const SkPicture*);
47
48static inline size_t SkImageMinRowBytes(const SkImage::Info& info) {
49    size_t rb = info.fWidth * SkImageBytesPerPixel(info.fColorType);
50    return SkAlign4(rb);
51}
52
53// Given an image created from SkNewImageFromBitmap, return its pixelref. This
54// may be called to see if the surface and the image share the same pixelref,
55// in which case the surface may need to perform a copy-on-write.
56extern SkPixelRef* SkBitmapImageGetPixelRef(SkImage* rasterImage);
57
58// Given an image created with NewTexture, return its GrTexture. This
59// may be called to see if the surface and the image share the same GrTexture,
60// in which case the surface may need to perform a copy-on-write.
61extern GrTexture* SkTextureImageGetTexture(SkImage* rasterImage);
62
63// Update the texture wrapped by an image created with NewTexture. This
64// is called when a surface and image share the same GrTexture and the
65// surface needs to perform a copy-on-write
66extern void SkTextureImageSetTexture(SkImage* image, GrTexture* texture);
67
68#endif
69