SkImageFilter.h revision 9c39744a00573b7133fc765b0a9d50a0ceace7b8
1894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com/* 2894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * Copyright 2011 Google Inc. 3894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * 4894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * Use of this source code is governed by a BSD-style license that can be 5894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * found in the LICENSE file. 6894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com */ 7894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com 8894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com#ifndef SkImageFilter_DEFINED 9894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com#define SkImageFilter_DEFINED 10894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com 11894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com#include "SkFlattenable.h" 12894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com 1315356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.comclass SkBitmap; 1476dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.comclass SkDevice; 1515356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.comclass SkMatrix; 16c73dd5c6880739f26216f198c757028fd28df1a4djsollen@google.comstruct SkIPoint; 17c73dd5c6880739f26216f198c757028fd28df1a4djsollen@google.comstruct SkIRect; 18c73dd5c6880739f26216f198c757028fd28df1a4djsollen@google.comstruct SkRect; 19894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.orgclass GrCustomStage; 20d0c1a06cb98dd4a009dfa79e37ba6ca23a8c180btomhudson@google.comclass GrTexture; 2115356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com 2215356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com/** 2315356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * Experimental. 2415356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * 2515356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * Base class for image filters. If one is installed in the paint, then 2615356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * all drawing occurs as usual, but it is as if the drawing happened into an 2715356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * offscreen (before the xfermode is applied). This offscreen bitmap will 2815356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * then be handed to the imagefilter, who in turn creates a new bitmap which 2915356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * is what will finally be drawn to the device (using the original xfermode). 3015356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com * 3132d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * THIS SIGNATURE IS TEMPORARY 3232d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * 3332d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * There are several weaknesses in this function signature: 3432d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * 1. Does not expose the destination/target device, so filters that can draw 3532d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * directly to it are unable to take advantage of that optimization. 3632d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * 2. Does not expose a way to create a "compabitible" image (i.e. gpu -> gpu) 3732d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * 3. As with #1, the filter is unable to "read" the dest (which would be slow) 3832d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * 3932d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * Therefore, we should not create any real dependencies on this API yet -- it 4032d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * is being checked in as a check-point so we can explore these and other 4132d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * considerations. 4215356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com */ 4354e01b2ab985e7a7d38109812069d056d128bfa1senorblanco@chromium.orgclass SK_API SkImageFilter : public SkFlattenable { 44894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.compublic: 450456e0b7b85060e9b9597ce414c4c2b19aff4f58robertphillips@google.com SK_DECLARE_INST_COUNT(SkImageFilter) 460456e0b7b85060e9b9597ce414c4c2b19aff4f58robertphillips@google.com 4776dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com class Proxy { 4876dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com public: 498926b169f6a0dfa4c2129a98ec2aee205f0c8527reed@google.com virtual ~Proxy() {}; 508926b169f6a0dfa4c2129a98ec2aee205f0c8527reed@google.com 5176dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com virtual SkDevice* createDevice(int width, int height) = 0; 528926b169f6a0dfa4c2129a98ec2aee205f0c8527reed@google.com // returns true if the proxy can handle this filter natively 538926b169f6a0dfa4c2129a98ec2aee205f0c8527reed@google.com virtual bool canHandleImageFilter(SkImageFilter*) = 0; 5476dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com // returns true if the proxy handled the filter itself. if this returns 5576dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com // false then the filter's code will be called. 5676dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com virtual bool filterImage(SkImageFilter*, const SkBitmap& src, 5776dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com const SkMatrix& ctm, 5876dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com SkBitmap* result, SkIPoint* offset) = 0; 5976dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com }; 60894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com 61894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com /** 62894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * Request a new (result) image to be created from the src image. 63894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * If the src has no pixels (isNull()) then the request just wants to 64894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * receive the config and width/height of the result. 65894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * 66894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * The matrix is the current matrix on the canvas. 67894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * 68894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * Offset is the amount to translate the resulting image relative to the 69fbfcd5602128ec010c82cb733c9cdc0a3254f9f3rmistry@google.com * src when it is drawn. 70894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * 71894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * If the result image cannot be created, return false, in which case both 72894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com * the result and offset parameters will be ignored by the caller. 73894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com */ 7476dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com bool filterImage(Proxy*, const SkBitmap& src, const SkMatrix& ctm, 7515356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com SkBitmap* result, SkIPoint* offset); 7615356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com 7715356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com /** 7832d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * Given the src bounds of an image, this returns the bounds of the result 7932d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com * image after the filter has been applied. 8032d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com */ 8132d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com bool filterBounds(const SkIRect& src, const SkMatrix& ctm, SkIRect* dst); 8232d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com 8332d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com /** 84894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org * Returns true if the filter can be expressed a single-pass 85894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org * GrCustomStage, used to process this filter on the GPU, or false if 86894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org * not. 87fbfcd5602128ec010c82cb733c9cdc0a3254f9f3rmistry@google.com * 88894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org * If stage is non-NULL, a new GrCustomStage instance is stored 89894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org * in it. The caller assumes ownership of the stage, and it is up to the 90894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org * caller to unref it. 91894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org */ 92d0c1a06cb98dd4a009dfa79e37ba6ca23a8c180btomhudson@google.com virtual bool asNewCustomStage(GrCustomStage** stage, GrTexture*) const; 93894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org 94894790d77c56cd4bae8070331d275c6d2897e33csenorblanco@chromium.org /** 95302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * Returns true if the filter can be processed on the GPU. This is most 96302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * often used for multi-pass effects, where intermediate results must be 97302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * rendered to textures. For single-pass effects, use asNewCustomStage(). 98302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * The default implementation returns false. 9905054f1a78a697b507580d0025db6c90423e033fsenorblanco@chromium.org */ 100302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org virtual bool canFilterImageGPU() const; 10105054f1a78a697b507580d0025db6c90423e033fsenorblanco@chromium.org 10205054f1a78a697b507580d0025db6c90423e033fsenorblanco@chromium.org /** 103302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * Process this image filter on the GPU. texture is the source texture 104302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * for processing, and rect is the effect region to process. The 105302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * function must allocate a new texture of at least rect width/height 106302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * size, and return it to the caller. The default implementation returns 107302cffba86a188373c99833d83392f33e6014542senorblanco@chromium.org * NULL. 10805054f1a78a697b507580d0025db6c90423e033fsenorblanco@chromium.org */ 1099c39744a00573b7133fc765b0a9d50a0ceace7b8senorblanco@chromium.org virtual GrTexture* onFilterImageGPU(Proxy*, GrTexture* texture, const SkRect& rect); 11005054f1a78a697b507580d0025db6c90423e033fsenorblanco@chromium.org 111894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.comprotected: 11254e01b2ab985e7a7d38109812069d056d128bfa1senorblanco@chromium.org SkImageFilter() {} 11354e01b2ab985e7a7d38109812069d056d128bfa1senorblanco@chromium.org explicit SkImageFilter(SkFlattenableReadBuffer& rb) : INHERITED(rb) {} 11432d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com 11532d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com // Default impl returns false 11676dd277b1fa021c42fc3acdd8d61e7dc05f9c267reed@google.com virtual bool onFilterImage(Proxy*, const SkBitmap& src, const SkMatrix&, 11715356a68b2a87e3ab9fc49392d085a4201ffeb62reed@google.com SkBitmap* result, SkIPoint* offset); 11832d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com // Default impl copies src into dst and returns true 11932d25b6f5f4355d4c5281694034ba3a5aa2cf571reed@google.com virtual bool onFilterBounds(const SkIRect&, const SkMatrix&, SkIRect*); 120894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com 121894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.comprivate: 12254e01b2ab985e7a7d38109812069d056d128bfa1senorblanco@chromium.org typedef SkFlattenable INHERITED; 123894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com}; 124894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com 125894aa9a7af0e5598600df694d184d3c7d2e454b0reed@google.com#endif 126