/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef __NS_FILTERINSTANCE_H__
#define __NS_FILTERINSTANCE_H__
#include "gfxMatrix.h"
#include "gfxPoint.h"
#include "gfxRect.h"
#include "nsCOMPtr.h"
#include "nsHashKeys.h"
#include "nsPoint.h"
#include "nsRect.h"
#include "nsSize.h"
#include "nsSVGFilters.h"
#include "nsSVGNumber2.h"
#include "nsSVGNumberPair.h"
#include "nsTArray.h"
#include "nsIFrame.h"
#include "mozilla/gfx/2D.h"
class gfxContext;
class nsIFrame;
class nsSVGFilterPaintCallback;
namespace mozilla {
namespace dom {
class UserSpaceMetrics;
} // namespace dom
} // namespace mozilla
/**
* This class performs all filter processing.
*
* We build a graph of the filter image data flow, essentially
* converting the filter graph to SSA. This lets us easily propagate
* analysis data (such as bounding-boxes) over the filter primitive graph.
*
* Definition of "filter space": filter space is a coordinate system that is
* aligned with the user space of the filtered element, with its origin located
* at the top left of the filter region, and with one unit equal in size to one
* pixel of the offscreen surface into which the filter output would/will be
* painted.
*
* The definition of "filter region" can be found here:
* http://www.w3.org/TR/SVG11/filters.html#FilterEffectsRegion
*/
class nsFilterInstance {
typedef mozilla::gfx::IntRect IntRect;
typedef mozilla::gfx::SourceSurface SourceSurface;
typedef mozilla::gfx::DrawTarget DrawTarget;
typedef mozilla::gfx::FilterPrimitiveDescription FilterPrimitiveDescription;
typedef mozilla::gfx::FilterDescription FilterDescription;
typedef mozilla::dom::UserSpaceMetrics UserSpaceMetrics;
typedef mozilla::image::imgDrawingParams imgDrawingParams;
public:
/**
* Create a FilterDescription for the supplied filter. All coordinates in
* the description are in filter space.
* @param aFilterInputIsTainted Describes whether the SourceImage /
* SourceAlpha input is tainted. This affects whether feDisplacementMap will
* respect the filter input as its map input, and it affects the IsTainted()
* state on the filter primitives in the FilterDescription. "Tainted" is a
* term from the filters spec and means security-sensitive content, i.e.
* pixels that JS should not be able to read in any way.
* @param aOutAdditionalImages Will contain additional images needed to
* render the filter (from feImage primitives).
* @return A FilterDescription describing the filter.
*/
static FilterDescription GetFilterDescription(
nsIContent* aFilteredElement, const nsTArray<nsStyleFilter>& aFilterChain,
bool aFilterInputIsTainted, const UserSpaceMetrics& aMetrics,
const gfxRect& aBBox,
nsTArray<RefPtr<SourceSurface>>& aOutAdditionalImages);
/**
* Paint the given filtered frame.
* @param aDirtyArea The area than needs to be painted, in aFilteredFrame's
* frame space (i.e. relative to its origin, the top-left corner of its
* border box).
*/
static void PaintFilteredFrame(nsIFrame* aFilteredFrame, gfxContext* aCtx,
nsSVGFilterPaintCallback* aPaintCallback,
const nsRegion* aDirtyArea,
imgDrawingParams& aImgParams);
/**
* Returns the post-filter area that could be dirtied when the given
* pre-filter area of aFilteredFrame changes.
* @param aPreFilterDirtyRegion The pre-filter area of aFilteredFrame that has
* changed, relative to aFilteredFrame, in app units.
*/
static nsRegion GetPostFilterDirtyArea(nsIFrame* aFilteredFrame,
const nsRegion& aPreFilterDirtyRegion);
/**
* Returns the pre-filter area that is needed from aFilteredFrame when the
* given post-filter area needs to be repainted.
* @param aPostFilterDirtyRegion The post-filter area that is dirty, relative
* to aFilteredFrame, in app units.
*/
static nsRegion GetPreFilterNeededArea(
nsIFrame* aFilteredFrame, const nsRegion& aPostFilterDirtyRegion);
/**
* Returns the post-filter visual overflow rect (paint bounds) of
* aFilteredFrame.
* @param aOverrideBBox A user space rect, in user units, that should be used
* as aFilteredFrame's bbox ('bbox' is a specific SVG term), if non-null.
* @param aPreFilterBounds The pre-filter visual overflow rect of
* aFilteredFrame, if non-null.
*/
static nsRect GetPostFilterBounds(nsIFrame* aFilteredFrame,
const gfxRect* aOverrideBBox = nullptr,
const nsRect* aPreFilterBounds = nullptr);
private:
/**
* @param aTargetFrame The frame of the filtered element under consideration,
* may be null.
* @param aTargetContent The filtered element itself.
* @param aMetrics The metrics to resolve SVG lengths against.
* @param aFilterChain The list of filters to apply.
* @param aFilterInputIsTainted Describes whether the SourceImage /
* SourceAlpha input is tainted. This affects whether feDisplacementMap will
* respect the filter input as its map input.
* @param aPaintCallback [optional] The callback that Render() should use to
* paint. Only required if you will call Render().
* @param aPaintTransform The transform to apply to convert to
* aTargetFrame's SVG user space. Only used when painting.
* @param aPostFilterDirtyRegion [optional] The post-filter area
* that has to be repainted, in app units. Only required if you will
* call ComputeSourceNeededRect() or Render().
* @param aPreFilterDirtyRegion [optional] The pre-filter area of
* the filtered element that changed, in app units. Only required if you
* will call ComputePostFilterDirtyRegion().
* @param aOverridePreFilterVisualOverflowRect [optional] Use a different
* visual overflow rect for the target element.
* @param aOverrideBBox [optional] Use a different SVG bbox for the target
* element. Must be non-null if aTargetFrame is null.
*/
nsFilterInstance(nsIFrame* aTargetFrame, nsIContent* aTargetContent,
const UserSpaceMetrics& aMetrics,
const nsTArray<nsStyleFilter>& aFilterChain,
bool aFilterInputIsTainted,
nsSVGFilterPaintCallback* aPaintCallback,
const gfxMatrix& aPaintTransform,
const nsRegion* aPostFilterDirtyRegion = nullptr,
const nsRegion* aPreFilterDirtyRegion = nullptr,
const nsRect* aOverridePreFilterVisualOverflowRect = nullptr,
const gfxRect* aOverrideBBox = nullptr);
/**
* Returns true if the filter instance was created successfully.
*/
bool IsInitialized() const { return mInitialized; }
/**
* Draws the filter output into aDrawTarget. The area that
* needs to be painted must have been specified before calling this method
* by passing it as the aPostFilterDirtyRegion argument to the
* nsFilterInstance constructor.
*/
void Render(gfxContext* aCtx, imgDrawingParams& aImgParams);
const FilterDescription& ExtractDescriptionAndAdditionalImages(
nsTArray<RefPtr<SourceSurface>>& aOutAdditionalImages) {
mInputImages.SwapElements(aOutAdditionalImages);
return mFilterDescription;
}
/**
* Sets the aPostFilterDirtyRegion outparam to the post-filter area in frame
* space that would be dirtied by mTargetFrame when a given
* pre-filter area of mTargetFrame is dirtied. The pre-filter area must have
* been specified before calling this method by passing it as the
* aPreFilterDirtyRegion argument to the nsFilterInstance constructor.
*/
nsRegion ComputePostFilterDirtyRegion();
/**
* Sets the aPostFilterExtents outparam to the post-filter bounds in frame
* space for the whole filter output. This is not necessarily equivalent to
* the area that would be dirtied in the result when the entire pre-filter
* area is dirtied, because some filter primitives can generate output
* without any input.
*/
nsRect ComputePostFilterExtents();
/**
* Sets the aDirty outparam to the pre-filter bounds in frame space of the
* area of mTargetFrame that is needed in order to paint the filtered output
* for a given post-filter dirtied area. The post-filter area must have been
* specified before calling this method by passing it as the
* aPostFilterDirtyRegion argument to the nsFilterInstance constructor.
*/
nsRect ComputeSourceNeededRect();
struct SourceInfo {
// Specifies which parts of the source need to be rendered.
// Set by ComputeNeededBoxes().
nsIntRect mNeededBounds;
// The surface that contains the input rendering.
// Set by BuildSourceImage / BuildSourcePaint.
RefPtr<SourceSurface> mSourceSurface;
// The position and size of mSourceSurface in filter space.
// Set by BuildSourceImage / BuildSourcePaint.
IntRect mSurfaceRect;
};
/**
* Creates a SourceSurface for either the FillPaint or StrokePaint graph
* nodes
*/
void BuildSourcePaint(SourceInfo* aPrimitive, imgDrawingParams& aImgParams);
/**
* Creates a SourceSurface for either the FillPaint and StrokePaint graph
* nodes, fills its contents and assigns it to mFillPaint.mSourceSurface and
* mStrokePaint.mSourceSurface respectively.
*/
void BuildSourcePaints(imgDrawingParams& aImgParams);
/**
* Creates the SourceSurface for the SourceGraphic graph node, paints its
* contents, and assigns it to mSourceGraphic.mSourceSurface.
*/
void BuildSourceImage(DrawTarget* aDest, imgDrawingParams& aImgParams);
/**
* Build the list of FilterPrimitiveDescriptions that describes the filter's
* filter primitives and their connections. This populates
* mPrimitiveDescriptions and mInputImages. aFilterInputIsTainted describes
* whether the SourceGraphic is tainted.
*/
nsresult BuildPrimitives(const nsTArray<nsStyleFilter>& aFilterChain,
nsIFrame* aTargetFrame, bool aFilterInputIsTainted);
/**
* Add to the list of FilterPrimitiveDescriptions for a particular SVG
* reference filter or CSS filter. This populates mPrimitiveDescriptions and
* mInputImages. aInputIsTainted describes whether the input to aFilter is
* tainted.
*/
nsresult BuildPrimitivesForFilter(const nsStyleFilter& aFilter,
nsIFrame* aTargetFrame,
bool aInputIsTainted);
/**
* Computes the filter space bounds of the areas that we actually *need* from
* the filter sources, based on the value of mPostFilterDirtyRegion.
* This sets mNeededBounds on the corresponding SourceInfo structs.
*/
void ComputeNeededBoxes();
/**
* Returns the output bounds of the final FilterPrimitiveDescription.
*/
nsIntRect OutputFilterSpaceBounds() const;
/**
* Compute the scale factors between user space and filter space.
*/
bool ComputeUserSpaceToFilterSpaceScale();
/**
* Transform a rect between user space and filter space.
*/
gfxRect UserSpaceToFilterSpace(const gfxRect& aUserSpace) const;
gfxRect FilterSpaceToUserSpace(const gfxRect& aFilterSpaceRect) const;
/**
* Converts an nsRect or an nsRegion that is relative to a filtered frame's
* origin (i.e. the top-left corner of its border box) into filter space,
* rounding out.
* Returns the entire filter region if aRect / aRegion is null, or if the
* result is too large to be stored in an nsIntRect.
*/
nsIntRect FrameSpaceToFilterSpace(const nsRect* aRect) const;
nsIntRegion FrameSpaceToFilterSpace(const nsRegion* aRegion) const;
/**
* Converts an nsIntRect or an nsIntRegion from filter space into the space
* that is relative to a filtered frame's origin (i.e. the top-left corner
* of its border box) in app units, rounding out.
*/
nsRect FilterSpaceToFrameSpace(const nsIntRect& aRect) const;
nsRegion FilterSpaceToFrameSpace(const nsIntRegion& aRegion) const;
/**
* Returns the transform from frame space to the coordinate space that
* GetCanvasTM transforms to. "Frame space" is the origin of a frame, aka the
* top-left corner of its border box, aka the top left corner of its mRect.
*/
gfxMatrix GetUserSpaceToFrameSpaceInCSSPxTransform() const;
bool ComputeTargetBBoxInFilterSpace();
/**
* The frame for the element that is currently being filtered.
*/
nsIFrame* mTargetFrame;
/**
* The filtered element.
*/
nsIContent* mTargetContent;
/**
* The user space metrics of the filtered frame.
*/
const UserSpaceMetrics& mMetrics;
nsSVGFilterPaintCallback* mPaintCallback;
/**
* The SVG bbox of the element that is being filtered, in user space.
*/
gfxRect mTargetBBox;
/**
* The SVG bbox of the element that is being filtered, in filter space.
*/
nsIntRect mTargetBBoxInFilterSpace;
/**
* Transform rects between filter space and frame space in CSS pixels.
*/
gfxMatrix mFilterSpaceToFrameSpaceInCSSPxTransform;
gfxMatrix mFrameSpaceInCSSPxToFilterSpaceTransform;
/**
* The scale factors between user space and filter space.
*/
gfxSize mUserSpaceToFilterSpaceScale;
gfxSize mFilterSpaceToUserSpaceScale;
/**
* Pre-filter paint bounds of the element that is being filtered, in filter
* space.
*/
nsIntRect mTargetBounds;
/**
* The dirty area that needs to be repainted, in filter space.
*/
nsIntRegion mPostFilterDirtyRegion;
/**
* The pre-filter area of the filtered element that changed, in filter space.
*/
nsIntRegion mPreFilterDirtyRegion;
SourceInfo mSourceGraphic;
SourceInfo mFillPaint;
SourceInfo mStrokePaint;
/**
* The transform to the SVG user space of mTargetFrame.
*/
gfxMatrix mPaintTransform;
nsTArray<RefPtr<SourceSurface>> mInputImages;
nsTArray<FilterPrimitiveDescription> mPrimitiveDescriptions;
FilterDescription mFilterDescription;
bool mInitialized;
};
#endif