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 // Convenience function to return a shader that implements the shader+image behavior defined for 24 // drawImage/Bitmap where the paint's shader is ignored when the bitmap is a color image, but 25 // properly compose them together when it is an alpha image. This allows the returned paint to 26 // be assigned to a paint clone without discarding the original behavior. 27 sk_sp<SkShader> SkMakeBitmapShaderForPaint(const SkPaint& paint, const SkBitmap& src, 28 SkTileMode, SkTileMode, const SkSamplingOptions&, 29 const SkMatrix* localMatrix, SkCopyPixelsMode); 30 31 // Given arguments for a call to SkCanvas::drawImageRect, modify the SkPaint and return a 32 // possibly adjusted 'dst' SkRect such that calling SkCanvas::drawRect(newDst, *paint) produces 33 // visually equivalent results to the original drawImageRect() call. 34 SkRect SkModifyPaintAndDstForDrawImageRect(const SkImage* image, 35 const SkSamplingOptions&, 36 SkRect src, 37 SkRect dst, 38 bool strictSrcSubset, 39 SkPaint* paint); 40 41 /** 42 * Examines the bitmap to decide if it can share the existing pixelRef, or 43 * if it needs to make a deep-copy of the pixels. 44 * 45 * The bitmap's pixelref will be shared if either the bitmap is marked as 46 * immutable, or CopyPixelsMode allows it. Shared pixel refs are also 47 * locked when kLocked_SharedPixelRefMode is specified. 48 * 49 * Passing kLocked_SharedPixelRefMode allows the image's peekPixels() method 50 * to succeed, but it will force any lazy decodes/generators to execute if 51 * they exist on the pixelref. 52 * 53 * It is illegal to call this with a texture-backed bitmap. 54 * 55 * If the bitmap's colortype cannot be converted into a corresponding 56 * SkImageInfo, or the bitmap's pixels cannot be accessed, this will return 57 * nullptr. 58 */ 59 extern SK_SPI sk_sp<SkImage> SkMakeImageFromRasterBitmap(const SkBitmap&, SkCopyPixelsMode); 60 61 // Given an image created from SkNewImageFromBitmap, return its pixelref. This 62 // may be called to see if the surface and the image share the same pixelref, 63 // in which case the surface may need to perform a copy-on-write. 64 extern const SkPixelRef* SkBitmapImageGetPixelRef(const SkImage* rasterImage); 65 66 /** 67 * Will attempt to upload and lock the contents of the image as a texture, so that subsequent 68 * draws to a gpu-target will come from that texture (and not by looking at the original image 69 * src). In particular this is intended to use the texture even if the image's original content 70 * changes subsequent to this call (i.e. the src is mutable!). 71 * 72 * All successful calls must be balanced by an equal number of calls to SkImage_unpinAsTexture(). 73 * 74 * Once in this "pinned" state, the image has all of the same thread restrictions that exist 75 * for a natively created gpu image (e.g. SkImage::MakeFromTexture) 76 * - all drawing, pinning, unpinning must happen in the same thread as the GrContext. 77 * 78 * @return true if the image was successfully uploaded and locked into a texture 79 */ 80 bool SkImage_pinAsTexture(const SkImage*, GrRecordingContext*); 81 82 /** 83 * The balancing call to a successful invokation of SkImage_pinAsTexture. When a balanced number of 84 * calls have been made, then the "pinned" texture is free to be purged, etc. This also means that a 85 * subsequent "pin" call will look at the original content again, and if its uniqueID/generationID 86 * has changed, then a newer texture will be uploaded/pinned. 87 * 88 * The context passed to unpin must match the one passed to pin. 89 */ 90 void SkImage_unpinAsTexture(const SkImage*, GrRecordingContext*); 91 92 #endif 93