/* * Copyright 2012 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #ifndef SkImage_DEFINED #define SkImage_DEFINED #include "SkFilterQuality.h" #include "SkImageInfo.h" #include "SkImageEncoder.h" #include "SkRefCnt.h" #include "SkScalar.h" #include "SkShader.h" class SkData; class SkCanvas; class SkColorTable; class SkImageGenerator; class SkPaint; class SkPicture; class SkPixelSerializer; class SkString; class SkSurface; class GrContext; class GrContextThreadSafeProxy; class GrTexture; /** * SkImage is an abstraction for drawing a rectagle of pixels, though the * particular type of image could be actually storing its data on the GPU, or * as drawing commands (picture or PDF or otherwise), ready to be played back * into another canvas. * * The content of SkImage is always immutable, though the actual storage may * change, if for example that image can be re-created via encoded data or * other means. * * SkImage always has a non-zero dimensions. If there is a request to create a new image, either * directly or via SkSurface, and either of the requested dimensions are zero, then NULL will be * returned. */ class SK_API SkImage : public SkRefCnt { public: typedef SkImageInfo Info; typedef void* ReleaseContext; static sk_sp MakeRasterCopy(const SkPixmap&); static sk_sp MakeRasterData(const Info&, sk_sp pixels, size_t rowBytes); typedef void (*RasterReleaseProc)(const void* pixels, ReleaseContext); /** * Return a new Image referencing the specified pixels. These must remain valid and unchanged * until the specified release-proc is called, indicating that Skia no longer has a reference * to the pixels. * * Returns NULL if the requested pixmap info is unsupported. */ static sk_sp MakeFromRaster(const SkPixmap&, RasterReleaseProc, ReleaseContext); /** * Construct a new image from the specified bitmap. If the bitmap is marked immutable, and * its pixel memory is shareable, it may be shared instead of copied. */ static sk_sp MakeFromBitmap(const SkBitmap&); /** * Construct a new SkImage based on the given ImageGenerator. Returns NULL on error. * This function will always take ownership of the passed generator. * * If a subset is specified, it must be contained within the generator's bounds. */ static sk_sp MakeFromGenerator(SkImageGenerator*, const SkIRect* subset = nullptr); /** * Construct a new SkImage based on the specified encoded data. Returns NULL on failure, * which can mean that the format of the encoded data was not recognized/supported. * * If a subset is specified, it must be contained within the encoded data's bounds. */ static sk_sp MakeFromEncoded(sk_sp encoded, const SkIRect* subset = nullptr); /** * Create a new image from the specified descriptor. Note - the caller is responsible for * managing the lifetime of the underlying platform texture. * * Will return NULL if the specified descriptor is unsupported. */ static sk_sp MakeFromTexture(GrContext* ctx, const GrBackendTextureDesc& desc) { return MakeFromTexture(ctx, desc, kPremul_SkAlphaType, nullptr, nullptr, nullptr); } static sk_sp MakeFromTexture(GrContext* ctx, const GrBackendTextureDesc& de, SkAlphaType at) { return MakeFromTexture(ctx, de, at, nullptr, nullptr, nullptr); } typedef void (*TextureReleaseProc)(ReleaseContext); /** * Create a new image from the specified descriptor. The underlying platform texture must stay * valid and unaltered until the specified release-proc is invoked, indicating that Skia * no longer is holding a reference to it. * * Will return NULL if the specified descriptor is unsupported. */ static sk_sp MakeFromTexture(GrContext* ctx, const GrBackendTextureDesc& desc, SkAlphaType at, TextureReleaseProc trp, ReleaseContext rc) { return MakeFromTexture(ctx, desc, at, nullptr, trp, rc); } /** * Create a new image from the specified descriptor. The underlying platform texture must stay * valid and unaltered until the specified release-proc is invoked, indicating that Skia * no longer is holding a reference to it. * * Will return NULL if the specified descriptor is unsupported. */ static sk_sp MakeFromTexture(GrContext*, const GrBackendTextureDesc&, SkAlphaType, sk_sp, TextureReleaseProc, ReleaseContext); /** * Create a new image from the specified descriptor. Note - Skia will delete or recycle the * texture when the image is released. * * Will return NULL if the specified descriptor is unsupported. */ static sk_sp MakeFromAdoptedTexture(GrContext*, const GrBackendTextureDesc&, SkAlphaType = kPremul_SkAlphaType, sk_sp = nullptr); /** * Create a new image by copying the pixels from the specified y, u, v textures. The data * from the textures is immediately ingested into the image and the textures can be modified or * deleted after the function returns. The image will have the dimensions of the y texture. */ static sk_sp MakeFromYUVTexturesCopy(GrContext*, SkYUVColorSpace, const GrBackendObject yuvTextureHandles[3], const SkISize yuvSizes[3], GrSurfaceOrigin, sk_sp = nullptr); /** * Create a new image by copying the pixels from the specified y and uv textures. The data * from the textures is immediately ingested into the image and the textures can be modified or * deleted after the function returns. The image will have the dimensions of the y texture. */ static sk_sp MakeFromNV12TexturesCopy(GrContext*, SkYUVColorSpace, const GrBackendObject nv12TextureHandles[2], const SkISize nv12Sizes[2], GrSurfaceOrigin, sk_sp = nullptr); static sk_sp MakeFromPicture(sk_sp, const SkISize& dimensions, const SkMatrix*, const SkPaint*); static sk_sp MakeTextureFromPixmap(GrContext*, const SkPixmap&, SkBudgeted budgeted); /////////////////////////////////////////////////////////////////////////////////////////////// int width() const { return fWidth; } int height() const { return fHeight; } SkISize dimensions() const { return SkISize::Make(fWidth, fHeight); } SkIRect bounds() const { return SkIRect::MakeWH(fWidth, fHeight); } uint32_t uniqueID() const { return fUniqueID; } SkAlphaType alphaType() const; /** * Returns true fi the image will be drawn as a mask, with no intrinsic color of its own. */ bool isAlphaOnly() const; bool isOpaque() const { return SkAlphaTypeIsOpaque(this->alphaType()); } /** * Extracts YUV planes from the SkImage and stores them in client-provided memory. The sizes * planes and rowBytes arrays are ordered [y, u, v]. */ bool readYUV8Planes(const SkISize[3], void* const planes[3], const size_t rowBytes[3], SkYUVColorSpace) const; sk_sp makeShader(SkShader::TileMode, SkShader::TileMode, const SkMatrix* localMatrix = nullptr) const; /** * If the image has direct access to its pixels (i.e. they are in local RAM) * return true, and if not null, return in the pixmap parameter the info about the * images pixels. * * On failure, return false and ignore the pixmap parameter. */ bool peekPixels(SkPixmap* pixmap) const; /** * Some images have to perform preliminary work in preparation for drawing. This can be * decoding, uploading to a GPU, or other tasks. These happen automatically when an image * is drawn, and often they are cached so that the cost is only paid the first time. * * Preroll() can be called before drawing to try to perform this prepatory work ahead of time. * For images that have no such work, this returns instantly. Others may do some thing to * prepare their cache and then return. * * If the image will drawn to a GPU-backed canvas or surface, pass the associated GrContext. * If the image will be drawn to any other type of canvas or surface, pass null. */ void preroll(GrContext* = nullptr) const; // DEPRECATED - currently used by Canvas2DLayerBridge in Chromium. GrTexture* getTexture() const; /** * Returns true if the image is texture backed. */ bool isTextureBacked() const; /** * Retrieves the backend API handle of the texture. If flushPendingGrContextIO then the * GrContext will issue to the backend API any deferred IO operations on the texture before * returning. */ GrBackendObject getTextureHandle(bool flushPendingGrContextIO) const; /** * Hints to image calls where the system might cache computed intermediates (e.g. the results * of decoding or a read-back from the GPU. Passing kAllow signals that the system's default * behavior is fine. Passing kDisallow signals that caching should be avoided. */ enum CachingHint { kAllow_CachingHint, kDisallow_CachingHint, }; /** * Copy the pixels from the image into the specified buffer (pixels + rowBytes), * converting them into the requested format (dstInfo). The image pixels are read * starting at the specified (srcX,srcY) location. * * The specified ImageInfo and (srcX,srcY) offset specifies a source rectangle * * srcR.setXYWH(srcX, srcY, dstInfo.width(), dstInfo.height()); * * srcR is intersected with the bounds of the image. If this intersection is not empty, * then we have two sets of pixels (of equal size). Replace the dst pixels with the * corresponding src pixels, performing any colortype/alphatype transformations needed * (in the case where the src and dst have different colortypes or alphatypes). * * This call can fail, returning false, for several reasons: * - If srcR does not intersect the image bounds. * - If the requested colortype/alphatype cannot be converted from the image's types. */ bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes, int srcX, int srcY, CachingHint = kAllow_CachingHint) const; bool readPixels(const SkPixmap& dst, int srcX, int srcY, CachingHint = kAllow_CachingHint) const; /** * Copy the pixels from this image into the dst pixmap, converting as needed into dst's * colortype/alphatype. If the conversion cannot be performed, false is returned. * * If dst's dimensions differ from the src dimension, the image will be scaled, applying the * specified filter-quality. */ bool scalePixels(const SkPixmap& dst, SkFilterQuality, CachingHint = kAllow_CachingHint) const; /** * Encode the image's pixels and return the result as a new SkData, which * the caller must manage (i.e. call unref() when they are done). * * If the image type cannot be encoded, or the requested encoder type is * not supported, this will return NULL. * * Note: this will attempt to encode the image's pixels in the specified format, * even if the image returns a data from refEncoded(). That data will be ignored. */ SkData* encode(SkImageEncoder::Type, int quality) const; /** * Encode the image and return the result as a caller-managed SkData. This will * attempt to reuse existing encoded data (as returned by refEncoded). * * We defer to the SkPixelSerializer both for vetting existing encoded data * (useEncodedData) and for encoding the image (encode) when no such data is * present or is rejected by the serializer. * * If not specified, we use a default serializer which 1) always accepts existing data * (in any format) and 2) encodes to PNG. * * If no compatible encoded data exists and encoding fails, this method will also * fail (return NULL). */ SkData* encode(SkPixelSerializer* = nullptr) const; /** * If the image already has its contents in encoded form (e.g. PNG or JPEG), return a ref * to that data (which the caller must call unref() on). The caller is responsible for calling * unref on the data when they are done. * * If the image does not already has its contents in encoded form, return NULL. * * Note: to force the image to return its contents as encoded data, try calling encode(...). */ SkData* refEncoded() const; const char* toString(SkString*) const; /** * Return a new image that is a subset of this image. The underlying implementation may * share the pixels, or it may make a copy. * * If subset does not intersect the bounds of this image, or the copy/share cannot be made, * NULL will be returned. */ sk_sp makeSubset(const SkIRect& subset) const; /** * Ensures that an image is backed by a texture (when GrContext is non-null). If no * transformation is required, the returned image may be the same as this image. If the this * image is from a different GrContext, this will fail. */ sk_sp makeTextureImage(GrContext*) const; /** * If the image is texture-backed this will make a raster copy of it (or nullptr if reading back * the pixels fails). Otherwise, it returns the original image. */ sk_sp makeNonTextureImage() const; /** * Apply a given image filter to this image, and return the filtered result. * * The subset represents the active portion of this image. The return value is similarly an * SkImage, with an active subset (outSubset). This is usually used with texture-backed * images, where the texture may be approx-match and thus larger than the required size. * * clipBounds constrains the device-space extent of the image which may be produced to the * given rect. * * offset is the amount to translate the resulting image relative to the src when it is drawn. * This is an out-param. * * If the result image cannot be created, or the result would be transparent black, null * is returned, in which case the offset and outSubset parameters should be ignored by the * caller. */ sk_sp makeWithFilter(const SkImageFilter* filter, const SkIRect& subset, const SkIRect& clipBounds, SkIRect* outSubset, SkIPoint* offset) const; /** Drawing params for which a deferred texture image data should be optimized. */ struct DeferredTextureImageUsageParams { DeferredTextureImageUsageParams(const SkMatrix matrix, const SkFilterQuality quality, int preScaleMipLevel) : fMatrix(matrix), fQuality(quality), fPreScaleMipLevel(preScaleMipLevel) {} SkMatrix fMatrix; SkFilterQuality fQuality; int fPreScaleMipLevel; }; /** * This method allows clients to capture the data necessary to turn a SkImage into a texture- * backed image. If the original image is codec-backed this will decode into a format optimized * for the context represented by the proxy. This method is thread safe with respect to the * GrContext whence the proxy came. Clients allocate and manage the storage of the deferred * texture data and control its lifetime. No cleanup is required, thus it is safe to simply free * the memory out from under the data. * * The same method is used both for getting the size necessary for pre-uploaded texture data * and for retrieving the data. The params array represents the set of draws over which to * optimize the pre-upload data. * * When called with a null buffer this returns the size that the client must allocate in order * to create deferred texture data for this image (or zero if this is an inappropriate * candidate). The buffer allocated by the client should be 8 byte aligned. * * When buffer is not null this fills in the deferred texture data for this image in the * provided buffer (assuming this is an appropriate candidate image and the buffer is * appropriately aligned). Upon success the size written is returned, otherwise 0. * * dstColorSpace is the color space of the surface where this texture will ultimately be used. * If the method determines that mip-maps are needed, this helps determine the correct strategy * for building them (gamma-correct or not). */ size_t getDeferredTextureImageData(const GrContextThreadSafeProxy&, const DeferredTextureImageUsageParams[], int paramCnt, void* buffer, SkColorSpace* dstColorSpace = nullptr) const; /** * Returns a texture-backed image from data produced in SkImage::getDeferredTextureImageData. * The context must be the context that provided the proxy passed to * getDeferredTextureImageData. */ static sk_sp MakeFromDeferredTextureImageData(GrContext*, const void*, SkBudgeted); // Helper functions to convert to SkBitmap enum LegacyBitmapMode { kRO_LegacyBitmapMode, kRW_LegacyBitmapMode, }; /** * Attempt to create a bitmap with the same pixels as the image. The result will always be * a raster-backed bitmap (texture-backed bitmaps are DEPRECATED, and not supported here). * * If the mode is kRO (read-only), the resulting bitmap will be marked as immutable. * * On succcess, returns true. On failure, returns false and the bitmap parameter will be reset * to empty. */ bool asLegacyBitmap(SkBitmap*, LegacyBitmapMode) const; /** * Returns true if the image is backed by an image-generator or other src that creates * (and caches) its pixels / texture on-demand. */ bool isLazyGenerated() const; protected: SkImage(int width, int height, uint32_t uniqueID); private: static sk_sp MakeTextureFromMipMap(GrContext*, const SkImageInfo&, const GrMipLevel* texels, int mipLevelCount, SkBudgeted, SkDestinationSurfaceColorMode); const int fWidth; const int fHeight; const uint32_t fUniqueID; typedef SkRefCnt INHERITED; }; #endif