1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/svg/nsFilterInstance.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,322 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef __NS_FILTERINSTANCE_H__
1.10 +#define __NS_FILTERINSTANCE_H__
1.11 +
1.12 +#include "gfxMatrix.h"
1.13 +#include "gfxPoint.h"
1.14 +#include "gfxRect.h"
1.15 +#include "nsCOMPtr.h"
1.16 +#include "nsHashKeys.h"
1.17 +#include "nsPoint.h"
1.18 +#include "nsRect.h"
1.19 +#include "nsSize.h"
1.20 +#include "nsSVGFilters.h"
1.21 +#include "nsSVGNumber2.h"
1.22 +#include "nsSVGNumberPair.h"
1.23 +#include "nsTArray.h"
1.24 +#include "nsIFrame.h"
1.25 +#include "mozilla/gfx/2D.h"
1.26 +
1.27 +class gfxASurface;
1.28 +class nsIFrame;
1.29 +class nsSVGFilterPaintCallback;
1.30 +
1.31 +/**
1.32 + * This class performs all filter processing.
1.33 + *
1.34 + * We build a graph of the filter image data flow, essentially
1.35 + * converting the filter graph to SSA. This lets us easily propagate
1.36 + * analysis data (such as bounding-boxes) over the filter primitive graph.
1.37 + *
1.38 + * Definition of "filter space": filter space is a coordinate system that is
1.39 + * aligned with the user space of the filtered element, with its origin located
1.40 + * at the top left of the filter region, and with one unit equal in size to one
1.41 + * pixel of the offscreen surface into which the filter output would/will be
1.42 + * painted.
1.43 + *
1.44 + * The definition of "filter region" can be found here:
1.45 + * http://www.w3.org/TR/SVG11/filters.html#FilterEffectsRegion
1.46 + */
1.47 +class nsFilterInstance
1.48 +{
1.49 + typedef mozilla::gfx::IntRect IntRect;
1.50 + typedef mozilla::gfx::SourceSurface SourceSurface;
1.51 + typedef mozilla::gfx::DrawTarget DrawTarget;
1.52 + typedef mozilla::gfx::FilterPrimitiveDescription FilterPrimitiveDescription;
1.53 +
1.54 +public:
1.55 + /**
1.56 + * Paint the given filtered frame.
1.57 + * @param aDirtyArea The area than needs to be painted, in aFilteredFrame's
1.58 + * frame space (i.e. relative to its origin, the top-left corner of its
1.59 + * border box).
1.60 + */
1.61 + static nsresult PaintFilteredFrame(nsRenderingContext *aContext,
1.62 + nsIFrame *aFilteredFrame,
1.63 + nsSVGFilterPaintCallback *aPaintCallback,
1.64 + const nsRegion* aDirtyArea,
1.65 + nsIFrame* aTransformRoot = nullptr);
1.66 +
1.67 + /**
1.68 + * Returns the post-filter area that could be dirtied when the given
1.69 + * pre-filter area of aFilteredFrame changes.
1.70 + * @param aPreFilterDirtyRegion The pre-filter area of aFilteredFrame that has
1.71 + * changed, relative to aFilteredFrame, in app units.
1.72 + */
1.73 + static nsRegion GetPostFilterDirtyArea(nsIFrame *aFilteredFrame,
1.74 + const nsRegion& aPreFilterDirtyRegion);
1.75 +
1.76 + /**
1.77 + * Returns the pre-filter area that is needed from aFilteredFrame when the
1.78 + * given post-filter area needs to be repainted.
1.79 + * @param aPostFilterDirtyRegion The post-filter area that is dirty, relative
1.80 + * to aFilteredFrame, in app units.
1.81 + */
1.82 + static nsRegion GetPreFilterNeededArea(nsIFrame *aFilteredFrame,
1.83 + const nsRegion& aPostFilterDirtyRegion);
1.84 +
1.85 + /**
1.86 + * Returns the post-filter visual overflow rect (paint bounds) of
1.87 + * aFilteredFrame.
1.88 + * @param aOverrideBBox A user space rect, in user units, that should be used
1.89 + * as aFilteredFrame's bbox ('bbox' is a specific SVG term), if non-null.
1.90 + * @param aPreFilterBounds The pre-filter visual overflow rect of
1.91 + * aFilteredFrame, if non-null.
1.92 + */
1.93 + static nsRect GetPostFilterBounds(nsIFrame *aFilteredFrame,
1.94 + const gfxRect *aOverrideBBox = nullptr,
1.95 + const nsRect *aPreFilterBounds = nullptr);
1.96 +
1.97 + /**
1.98 + * @param aTargetFrame The frame of the filtered element under consideration.
1.99 + * @param aPaintCallback [optional] The callback that Render() should use to
1.100 + * paint. Only required if you will call Render().
1.101 + * @param aPostFilterDirtyRegion [optional] The post-filter area
1.102 + * that has to be repainted, in app units. Only required if you will
1.103 + * call ComputeSourceNeededRect() or Render().
1.104 + * @param aPreFilterDirtyRegion [optional] The pre-filter area of
1.105 + * the filtered element that changed, in app units. Only required if you
1.106 + * will call ComputePostFilterDirtyRegion().
1.107 + * @param aOverridePreFilterVisualOverflowRect [optional] Use a different
1.108 + * visual overflow rect for the target element.
1.109 + * @param aOverrideBBox [optional] Use a different SVG bbox for the target
1.110 + * element.
1.111 + * @param aTransformRoot [optional] The transform root frame for painting.
1.112 + */
1.113 + nsFilterInstance(nsIFrame *aTargetFrame,
1.114 + nsSVGFilterPaintCallback *aPaintCallback,
1.115 + const nsRegion *aPostFilterDirtyRegion = nullptr,
1.116 + const nsRegion *aPreFilterDirtyRegion = nullptr,
1.117 + const nsRect *aOverridePreFilterVisualOverflowRect = nullptr,
1.118 + const gfxRect *aOverrideBBox = nullptr,
1.119 + nsIFrame* aTransformRoot = nullptr);
1.120 +
1.121 + /**
1.122 + * Returns true if the filter instance was created successfully.
1.123 + */
1.124 + bool IsInitialized() const { return mInitialized; }
1.125 +
1.126 + /**
1.127 + * Draws the filter output into aContext. The area that
1.128 + * needs to be painted must have been specified before calling this method
1.129 + * by passing it as the aPostFilterDirtyRegion argument to the
1.130 + * nsFilterInstance constructor.
1.131 + */
1.132 + nsresult Render(gfxContext* aContext);
1.133 +
1.134 + /**
1.135 + * Sets the aPostFilterDirtyRegion outparam to the post-filter area in frame
1.136 + * space that would be dirtied by mTargetFrame when a given
1.137 + * pre-filter area of mTargetFrame is dirtied. The pre-filter area must have
1.138 + * been specified before calling this method by passing it as the
1.139 + * aPreFilterDirtyRegion argument to the nsFilterInstance constructor.
1.140 + */
1.141 + nsresult ComputePostFilterDirtyRegion(nsRegion* aPostFilterDirtyRegion);
1.142 +
1.143 + /**
1.144 + * Sets the aPostFilterExtents outparam to the post-filter bounds in frame
1.145 + * space for the whole filter output. This is not necessarily equivalent to
1.146 + * the area that would be dirtied in the result when the entire pre-filter
1.147 + * area is dirtied, because some filter primitives can generate output
1.148 + * without any input.
1.149 + */
1.150 + nsresult ComputePostFilterExtents(nsRect* aPostFilterExtents);
1.151 +
1.152 + /**
1.153 + * Sets the aDirty outparam to the pre-filter bounds in frame space of the
1.154 + * area of mTargetFrame that is needed in order to paint the filtered output
1.155 + * for a given post-filter dirtied area. The post-filter area must have been
1.156 + * specified before calling this method by passing it as the aPostFilterDirtyRegion
1.157 + * argument to the nsFilterInstance constructor.
1.158 + */
1.159 + nsresult ComputeSourceNeededRect(nsRect* aDirty);
1.160 +
1.161 +
1.162 + /**
1.163 + * Returns the transform from filter space to outer-<svg> device space.
1.164 + */
1.165 + gfxMatrix GetFilterSpaceToDeviceSpaceTransform() const {
1.166 + return mFilterSpaceToDeviceSpaceTransform;
1.167 + }
1.168 +
1.169 +private:
1.170 + struct SourceInfo {
1.171 + // Specifies which parts of the source need to be rendered.
1.172 + // Set by ComputeNeededBoxes().
1.173 + nsIntRect mNeededBounds;
1.174 +
1.175 + // The surface that contains the input rendering.
1.176 + // Set by BuildSourceImage / BuildSourcePaint.
1.177 + mozilla::RefPtr<SourceSurface> mSourceSurface;
1.178 +
1.179 + // The position and size of mSourceSurface in filter space.
1.180 + // Set by BuildSourceImage / BuildSourcePaint.
1.181 + IntRect mSurfaceRect;
1.182 + };
1.183 +
1.184 + /**
1.185 + * Creates a SourceSurface for either the FillPaint or StrokePaint graph
1.186 + * nodes
1.187 + */
1.188 + nsresult BuildSourcePaint(SourceInfo *aPrimitive,
1.189 + gfxASurface* aTargetSurface,
1.190 + DrawTarget* aTargetDT);
1.191 +
1.192 + /**
1.193 + * Creates a SourceSurface for either the FillPaint and StrokePaint graph
1.194 + * nodes, fills its contents and assigns it to mFillPaint.mSourceSurface and
1.195 + * mStrokePaint.mSourceSurface respectively.
1.196 + */
1.197 + nsresult BuildSourcePaints(gfxASurface* aTargetSurface,
1.198 + DrawTarget* aTargetDT);
1.199 +
1.200 + /**
1.201 + * Creates the SourceSurface for the SourceGraphic graph node, paints its
1.202 + * contents, and assigns it to mSourceGraphic.mSourceSurface.
1.203 + */
1.204 + nsresult BuildSourceImage(gfxASurface* aTargetSurface,
1.205 + DrawTarget* aTargetDT);
1.206 +
1.207 + /**
1.208 + * Build the list of FilterPrimitiveDescriptions that describes the filter's
1.209 + * filter primitives and their connections. This populates
1.210 + * mPrimitiveDescriptions and mInputImages.
1.211 + */
1.212 + nsresult BuildPrimitives();
1.213 +
1.214 + /**
1.215 + * Add to the list of FilterPrimitiveDescriptions for a particular SVG
1.216 + * reference filter or CSS filter. This populates mPrimitiveDescrs and
1.217 + * mInputImages.
1.218 + */
1.219 + nsresult BuildPrimitivesForFilter(const nsStyleFilter& aFilter);
1.220 +
1.221 + /**
1.222 + * Computes the filter space bounds of the areas that we actually *need* from
1.223 + * the filter sources, based on the value of mPostFilterDirtyRegion.
1.224 + * This sets mNeededBounds on the corresponding SourceInfo structs.
1.225 + */
1.226 + void ComputeNeededBoxes();
1.227 +
1.228 + /**
1.229 + * Compute the scale factors between user space and filter space.
1.230 + */
1.231 + nsresult ComputeUserSpaceToFilterSpaceScale();
1.232 +
1.233 + /**
1.234 + * Transform a rect between user space and filter space.
1.235 + */
1.236 + gfxRect UserSpaceToFilterSpace(const gfxRect& aUserSpace) const;
1.237 + gfxRect FilterSpaceToUserSpace(const gfxRect& aFilterSpaceRect) const;
1.238 +
1.239 + /**
1.240 + * Converts an nsRect or an nsRegion that is relative to a filtered frame's
1.241 + * origin (i.e. the top-left corner of its border box) into filter space,
1.242 + * rounding out.
1.243 + * Returns the entire filter region if aRect / aRegion is null, or if the
1.244 + * result is too large to be stored in an nsIntRect.
1.245 + */
1.246 + nsIntRect FrameSpaceToFilterSpace(const nsRect* aRect) const;
1.247 + nsIntRegion FrameSpaceToFilterSpace(const nsRegion* aRegion) const;
1.248 +
1.249 + /**
1.250 + * Converts an nsIntRect or an nsIntRegion from filter space into the space
1.251 + * that is relative to a filtered frame's origin (i.e. the top-left corner
1.252 + * of its border box) in app units, rounding out.
1.253 + */
1.254 + nsRect FilterSpaceToFrameSpace(const nsIntRect& aRect) const;
1.255 + nsRegion FilterSpaceToFrameSpace(const nsIntRegion& aRegion) const;
1.256 +
1.257 + /**
1.258 + * Returns the transform from frame space to the coordinate space that
1.259 + * GetCanvasTM transforms to. "Frame space" is the origin of a frame, aka the
1.260 + * top-left corner of its border box, aka the top left corner of its mRect.
1.261 + */
1.262 + gfxMatrix GetUserSpaceToFrameSpaceInCSSPxTransform() const;
1.263 +
1.264 + /**
1.265 + * The frame for the element that is currently being filtered.
1.266 + */
1.267 + nsIFrame* mTargetFrame;
1.268 +
1.269 + nsSVGFilterPaintCallback* mPaintCallback;
1.270 +
1.271 + /**
1.272 + * The SVG bbox of the element that is being filtered, in user space.
1.273 + */
1.274 + gfxRect mTargetBBox;
1.275 +
1.276 + /**
1.277 + * The transform from filter space to outer-<svg> device space.
1.278 + */
1.279 + gfxMatrix mFilterSpaceToDeviceSpaceTransform;
1.280 +
1.281 + /**
1.282 + * Transform rects between filter space and frame space in CSS pixels.
1.283 + */
1.284 + gfxMatrix mFilterSpaceToFrameSpaceInCSSPxTransform;
1.285 + gfxMatrix mFrameSpaceInCSSPxToFilterSpaceTransform;
1.286 +
1.287 + /**
1.288 + * The "filter region", in the filtered element's user space.
1.289 + */
1.290 + gfxRect mUserSpaceBounds;
1.291 + nsIntRect mFilterSpaceBounds;
1.292 +
1.293 + /**
1.294 + * The scale factors between user space and filter space.
1.295 + */
1.296 + gfxSize mUserSpaceToFilterSpaceScale;
1.297 + gfxSize mFilterSpaceToUserSpaceScale;
1.298 +
1.299 + /**
1.300 + * Pre-filter paint bounds of the element that is being filtered, in filter
1.301 + * space.
1.302 + */
1.303 + nsIntRect mTargetBounds;
1.304 +
1.305 + /**
1.306 + * The dirty area that needs to be repainted, in filter space.
1.307 + */
1.308 + nsIntRegion mPostFilterDirtyRegion;
1.309 +
1.310 + /**
1.311 + * The pre-filter area of the filtered element that changed, in filter space.
1.312 + */
1.313 + nsIntRegion mPreFilterDirtyRegion;
1.314 +
1.315 + SourceInfo mSourceGraphic;
1.316 + SourceInfo mFillPaint;
1.317 + SourceInfo mStrokePaint;
1.318 + nsIFrame* mTransformRoot;
1.319 + nsTArray<mozilla::RefPtr<SourceSurface>> mInputImages;
1.320 + nsTArray<FilterPrimitiveDescription> mPrimitiveDescriptions;
1.321 + int32_t mAppUnitsPerCSSPx;
1.322 + bool mInitialized;
1.323 +};
1.324 +
1.325 +#endif
