gecko-dev/layout/svg/nsSVGIntegrationUtils.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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 NSSVGINTEGRATIONUTILS_H_
#define NSSVGINTEGRATIONUTILS_H_
#include "gfxMatrix.h"
#include "gfxPattern.h"
#include "gfxRect.h"
#include "nsRect.h"
class nsDisplayList;
class nsDisplayListBuilder;
class nsIFrame;
class nsRenderingContext;
namespace mozilla {
namespace layers {
class LayerManager;
}
}
struct nsPoint;
struct nsSize;
/**
* Integration of SVG effects (clipPath clipping, masking and filters) into
* regular display list based painting and hit-testing.
*/
class nsSVGIntegrationUtils MOZ_FINAL
{
public:
/**
* Returns true if SVG effects are currently applied to this frame.
*/
static bool
UsingEffectsForFrame(const nsIFrame* aFrame);
/**
* In SVG, an element's "user space" is simply the coordinate system in place
* at the time that it is drawn. For non-SVG frames, we want any SVG effects
* to be applied to the union of the border-box rects of all of a given
* frame's continuations. This means that, when we paint a non-SVG frame with
* effects, we want to offset the effects by the distance from the frame's
* origin (the top left of its border box) to the top left of the union of
* the border-box rects of all its continuations. In other words, we need to
* apply this offset as a suplimental translation to the current coordinate
* system in order to establish the correct user space before calling into
* the SVG effects code. For the purposes of the nsSVGIntegrationUtils code
* we somewhat misappropriate the term "user space" by using it to refer
* specifically to this adjusted coordinate system.
*
* For consistency with nsIFrame::GetOffsetTo, the offset this method returns
* is the offset you need to add to a point that's relative to aFrame's
* origin (the top left of its border box) to convert it to aFrame's user
* space. In other words the value returned is actually the offset from the
* origin of aFrame's user space to aFrame.
*
* Note: This method currently only accepts a frame's first continuation
* since none of our current callers need to be able to pass in other
* continuations.
*/
static nsPoint
GetOffsetToUserSpace(nsIFrame* aFrame);
/**
* Returns the size of the union of the border-box rects of all of
* aNonSVGFrame's continuations.
*/
static nsSize
GetContinuationUnionSize(nsIFrame* aNonSVGFrame);
/**
* When SVG effects need to resolve percentage, userSpaceOnUse lengths, they
* need a coordinate context to resolve them against. This method provides
* that coordinate context for non-SVG frames with SVG effects applied to
* them. The gfxSize returned is the size of the union of all of the given
* frame's continuations' border boxes, converted to SVG user units (equal to
* CSS px units), as required by the SVG code.
*/
static gfxSize
GetSVGCoordContextForNonSVGFrame(nsIFrame* aNonSVGFrame);
/**
* SVG effects such as SVG filters, masking and clipPath may require an SVG
* "bbox" for the element they're being applied to in order to make decisions
* about positioning, and to resolve various lengths against. This method
* provides the "bbox" for non-SVG frames. The bbox returned is in CSS px
* units, and is the union of all aNonSVGFrame's continuations' overflow
* areas, relative to the top-left of the union of all aNonSVGFrame's
* continuations' border box rects.
*/
static gfxRect
GetSVGBBoxForNonSVGFrame(nsIFrame* aNonSVGFrame);
/**
* Used to adjust a frame's pre-effects visual overflow rect to take account
* of SVG effects.
*
* XXX This method will not do the right thing for frames with continuations.
* It really needs all the continuations to have been reflowed before being
* called, but we currently call it on each continuation as its overflow
* rects are set during the reflow of each particular continuation. Gecko's
* current reflow architecture does not allow us to set the overflow rects
* for a whole chain of continuations for a given element at the point when
* the last continuation is reflowed. See:
* http://groups.google.com/group/mozilla.dev.tech.layout/msg/6b179066f3051f65
*/
static nsRect
ComputePostEffectsVisualOverflowRect(nsIFrame* aFrame,
const nsRect& aPreEffectsOverflowRect);
/**
* Used to adjust the area of a frame that needs to be invalidated to take
* account of SVG effects.
*
* @param aFrame The effects frame.
* @param aToReferenceFrame The offset (in app units) from aFrame to its
* reference display item.
* @param aInvalidRect The pre-effects invalid rect in pixels relative to
* the reference display item.
* @return The post-effects invalid rect in pixels relative to the reference
* display item.
*/
static nsIntRect
AdjustInvalidAreaForSVGEffects(nsIFrame* aFrame, const nsPoint& aToReferenceFrame,
const nsIntRect& aInvalidRect);
/**
* Figure out which area of the source is needed given an area to
* repaint
*/
static nsRect
GetRequiredSourceForInvalidArea(nsIFrame* aFrame, const nsRect& aDamageRect);
/**
* Returns true if the given point is not clipped out by effects.
* @param aPt in appunits relative to aFrame
*/
static bool
HitTestFrameForEffects(nsIFrame* aFrame, const nsPoint& aPt);
/**
* Paint non-SVG frame with SVG effects.
*/
static void
PaintFramesWithEffects(nsRenderingContext* aCtx,
nsIFrame* aFrame, const nsRect& aDirtyRect,
nsDisplayListBuilder* aBuilder,
mozilla::layers::LayerManager* aManager);
/**
* SVG frames expect to paint in SVG user units, which are equal to CSS px
* units. This method provides a transform matrix to multiply onto a
* gfxContext's current transform to convert the context's current units from
* its usual dev pixels to SVG user units/CSS px to keep the SVG code happy.
*/
static gfxMatrix
GetCSSPxToDevPxMatrix(nsIFrame* aNonSVGFrame);
/**
* @param aRenderingContext the target rendering context in which the paint
* server will be rendered
* @param aTarget the target frame onto which the paint server will be
* rendered
* @param aPaintServer a first-continuation frame to use as the source
* @param aFilter a filter to be applied when scaling
* @param aDest the area the paint server image should be mapped to
* @param aFill the area to be filled with copies of the paint server image
* @param aAnchor a point in aFill which we will ensure is pixel-aligned in
* the output
* @param aDirty pixels outside this area may be skipped
* @param aPaintServerSize the size that would be filled when using
* background-repeat:no-repeat and background-size:auto. For normal background
* images, this would be the intrinsic size of the image; for gradients and
* patterns this would be the whole target frame fill area.
*/
static void
DrawPaintServer(nsRenderingContext* aRenderingContext,
nsIFrame* aTarget,
nsIFrame* aPaintServer,
gfxPattern::GraphicsFilter aFilter,
const nsRect& aDest,
const nsRect& aFill,
const nsPoint& aAnchor,
const nsRect& aDirty,
const nsSize& aPaintServerSize);
};
#endif /*NSSVGINTEGRATIONUTILS_H_*/