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 "include/core/SkImage.h" 12 #include "include/core/SkSurface.h" 13 #include "include/core/SkTileMode.h" 14 15 class SkPixelRef; 16 17 enum SkCopyPixelsMode { 18 kIfMutable_SkCopyPixelsMode, //!< only copy src pixels if they are marked mutable 19 kAlways_SkCopyPixelsMode, //!< always copy src pixels (even if they are marked immutable) 20 kNever_SkCopyPixelsMode, //!< never copy src pixels (even if they are marked mutable) 21 }; 22 23 // A good size for creating shader contexts on the stack. 24 enum {kSkBlitterContextSize = 3332}; 25 26 // If alloc is non-nullptr, it will be used to allocate the returned SkShader, and MUST outlive 27 // the SkShader. 28 sk_sp<SkShader> SkMakeBitmapShader(const SkBitmap& src, SkTileMode, SkTileMode, 29 const SkSamplingOptions&, const SkMatrix* localMatrix, 30 SkCopyPixelsMode); 31 32 // Convenience function to return a shader that implements the shader+image behavior defined for 33 // drawImage/Bitmap where the paint's shader is ignored when the bitmap is a color image, but 34 // properly compose them together when it is an alpha image. This allows the returned paint to 35 // be assigned to a paint clone without discarding the original behavior. 36 sk_sp<SkShader> SkMakeBitmapShaderForPaint(const SkPaint& paint, const SkBitmap& src, 37 SkTileMode, SkTileMode, const SkSamplingOptions&, 38 const SkMatrix* localMatrix, SkCopyPixelsMode); 39 40 /** 41 * Examines the bitmap to decide if it can share the existing pixelRef, or 42 * if it needs to make a deep-copy of the pixels. 43 * 44 * The bitmap's pixelref will be shared if either the bitmap is marked as 45 * immutable, or CopyPixelsMode allows it. Shared pixel refs are also 46 * locked when kLocked_SharedPixelRefMode is specified. 47 * 48 * Passing kLocked_SharedPixelRefMode allows the image's peekPixels() method 49 * to succeed, but it will force any lazy decodes/generators to execute if 50 * they exist on the pixelref. 51 * 52 * It is illegal to call this with a texture-backed bitmap. 53 * 54 * If the bitmap's colortype cannot be converted into a corresponding 55 * SkImageInfo, or the bitmap's pixels cannot be accessed, this will return 56 * nullptr. 57 */ 58 extern SK_SPI sk_sp<SkImage> SkMakeImageFromRasterBitmap(const SkBitmap&, SkCopyPixelsMode); 59 60 // Given an image created from SkNewImageFromBitmap, return its pixelref. This 61 // may be called to see if the surface and the image share the same pixelref, 62 // in which case the surface may need to perform a copy-on-write. 63 extern const SkPixelRef* SkBitmapImageGetPixelRef(const SkImage* rasterImage); 64 65 /** 66 * Will attempt to upload and lock the contents of the image as a texture, so that subsequent 67 * draws to a gpu-target will come from that texture (and not by looking at the original image 68 * src). In particular this is intended to use the texture even if the image's original content 69 * changes subsequent to this call (i.e. the src is mutable!). 70 * 71 * All successful calls must be balanced by an equal number of calls to SkImage_unpinAsTexture(). 72 * 73 * Once in this "pinned" state, the image has all of the same thread restrictions that exist 74 * for a natively created gpu image (e.g. SkImage::MakeFromTexture) 75 * - all drawing, pinning, unpinning must happen in the same thread as the GrContext. 76 * 77 * @return true if the image was successfully uploaded and locked into a texture 78 */ 79 extern SK_SPI bool SkImage_pinAsTexture(const SkImage*, GrRecordingContext*); 80 81 /** 82 * The balancing call to a successful invokation of SkImage_pinAsTexture. When a balanced number of 83 * calls have been made, then the "pinned" texture is free to be purged, etc. This also means that a 84 * subsequent "pin" call will look at the original content again, and if its uniqueID/generationID 85 * has changed, then a newer texture will be uploaded/pinned. 86 * 87 * The context passed to unpin must match the one passed to pin. 88 */ 89 extern SK_SPI void SkImage_unpinAsTexture(const SkImage*, GrRecordingContext*); 90 91 #endif 92