mirror of
https://gitlab.winehq.org/wine/wine-gecko.git
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648 lines
28 KiB
C++
648 lines
28 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/* utility functions for drawing borders and backgrounds */
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#ifndef nsCSSRendering_h___
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#define nsCSSRendering_h___
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#include "nsStyleConsts.h"
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#include "gfxBlur.h"
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#include "gfxContext.h"
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#include "gfxImageSurface.h"
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#include "nsLayoutUtils.h"
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struct nsPoint;
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class nsStyleContext;
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class nsPresContext;
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class nsRenderingContext;
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/**
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* This is a small wrapper class to encapsulate image drawing that can draw an
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* nsStyleImage image, which may internally be a real image, a sub image, or a
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* CSS gradient.
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*
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* @note Always call the member functions in the order of PrepareImage(),
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* ComputeSize(), and Draw().
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*/
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class nsImageRenderer {
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public:
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typedef mozilla::layers::ImageContainer ImageContainer;
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enum {
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FLAG_SYNC_DECODE_IMAGES = 0x01
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};
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nsImageRenderer(nsIFrame* aForFrame, const nsStyleImage* aImage, PRUint32 aFlags);
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~nsImageRenderer();
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/**
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* Populates member variables to get ready for rendering.
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* @return true iff the image is ready, and there is at least a pixel to
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* draw.
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*/
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bool PrepareImage();
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/**
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* @return the image size in appunits when rendered, after accounting for the
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* background positioning area, background-size, and the image's intrinsic
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* dimensions (if any).
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*/
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nsSize ComputeSize(const nsStyleBackground::Size& aLayerSize,
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const nsSize& aBgPositioningArea);
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/**
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* Draws the image to the target rendering context.
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* @see nsLayoutUtils::DrawImage() for other parameters
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*/
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void Draw(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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const nsRect& aDest,
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const nsRect& aFill,
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const nsPoint& aAnchor,
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const nsRect& aDirty);
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bool IsRasterImage();
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already_AddRefed<ImageContainer> GetContainer();
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private:
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/*
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* Compute the "unscaled" dimensions of the image in aUnscaled{Width,Height}
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* and aRatio. Whether the image has a height and width are indicated by
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* aHaveWidth and aHaveHeight. If the image doesn't have a ratio, aRatio will
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* be (0, 0).
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*/
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void ComputeUnscaledDimensions(const nsSize& aBgPositioningArea,
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nscoord& aUnscaledWidth, bool& aHaveWidth,
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nscoord& aUnscaledHeight, bool& aHaveHeight,
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nsSize& aRatio);
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/*
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* Using the previously-computed unscaled width and height (if each are
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* valid, as indicated by aHaveWidth/aHaveHeight), compute the size at which
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* the image should actually render.
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*/
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nsSize
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ComputeDrawnSize(const nsStyleBackground::Size& aLayerSize,
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const nsSize& aBgPositioningArea,
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nscoord aUnscaledWidth, bool aHaveWidth,
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nscoord aUnscaledHeight, bool aHaveHeight,
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const nsSize& aIntrinsicRatio);
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nsIFrame* mForFrame;
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const nsStyleImage* mImage;
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nsStyleImageType mType;
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nsCOMPtr<imgIContainer> mImageContainer;
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nsRefPtr<nsStyleGradient> mGradientData;
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nsIFrame* mPaintServerFrame;
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nsLayoutUtils::SurfaceFromElementResult mImageElementSurface;
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bool mIsReady;
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nsSize mSize; // unscaled size of the image, in app units
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PRUint32 mFlags;
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};
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/**
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* A struct representing all the information needed to paint a background
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* image to some target, taking into account all CSS background-* properties.
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* See PrepareBackgroundLayer.
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*/
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struct nsBackgroundLayerState {
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/**
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* @param aFlags some combination of nsCSSRendering::PAINTBG_* flags
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*/
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nsBackgroundLayerState(nsIFrame* aForFrame, const nsStyleImage* aImage, PRUint32 aFlags)
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: mImageRenderer(aForFrame, aImage, aFlags) {}
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/**
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* The nsImageRenderer that will be used to draw the background.
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*/
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nsImageRenderer mImageRenderer;
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/**
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* A rectangle that one copy of the image tile is mapped onto. Same
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* coordinate system as aBorderArea/aBGClipRect passed into
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* PrepareBackgroundLayer.
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*/
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nsRect mDestArea;
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/**
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* The actual rectangle that should be filled with (complete or partial)
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* image tiles. Same coordinate system as aBorderArea/aBGClipRect passed into
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* PrepareBackgroundLayer.
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*/
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nsRect mFillArea;
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/**
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* The anchor point that should be snapped to a pixel corner. Same
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* coordinate system as aBorderArea/aBGClipRect passed into
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* PrepareBackgroundLayer.
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*/
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nsPoint mAnchor;
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};
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struct nsCSSRendering {
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/**
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* Initialize any static variables used by nsCSSRendering.
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*/
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static void Init();
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/**
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* Clean up any static variables used by nsCSSRendering.
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*/
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static void Shutdown();
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static void PaintBoxShadowInner(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aFrameArea,
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const nsRect& aDirtyRect);
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static void PaintBoxShadowOuter(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aFrameArea,
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const nsRect& aDirtyRect);
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static void ComputePixelRadii(const nscoord *aAppUnitsRadii,
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nscoord aAppUnitsPerPixel,
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gfxCornerSizes *oBorderRadii);
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/**
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* Render the border for an element using css rendering rules
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* for borders. aSkipSides is a bitmask of the sides to skip
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* when rendering. If 0 then no sides are skipped.
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*/
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static void PaintBorder(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aDirtyRect,
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const nsRect& aBorderArea,
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nsStyleContext* aStyleContext,
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int aSkipSides = 0);
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/**
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* Like PaintBorder, but taking an nsStyleBorder argument instead of
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* getting it from aStyleContext.
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*/
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static void PaintBorderWithStyleBorder(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aDirtyRect,
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const nsRect& aBorderArea,
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const nsStyleBorder& aBorderStyle,
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nsStyleContext* aStyleContext,
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int aSkipSides = 0);
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/**
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* Render the outline for an element using css rendering rules
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* for borders. aSkipSides is a bitmask of the sides to skip
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* when rendering. If 0 then no sides are skipped.
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*/
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static void PaintOutline(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aDirtyRect,
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const nsRect& aBorderArea,
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nsStyleContext* aStyleContext);
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/**
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* Render keyboard focus on an element.
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* |aFocusRect| is the outer rectangle of the focused element.
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* Uses a fixed style equivalent to "1px dotted |aColor|".
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* Not used for controls, because the native theme may differ.
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*/
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static void PaintFocus(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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const nsRect& aFocusRect,
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nscolor aColor);
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/**
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* Render a gradient for an element.
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*/
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static void PaintGradient(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsStyleGradient* aGradient,
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const nsRect& aDirtyRect,
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const nsRect& aOneCellArea,
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const nsRect& aFillArea);
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/**
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* Find the frame whose background style should be used to draw the
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* canvas background. aForFrame must be the frame for the root element
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* whose background style should be used. This function will return
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* aForFrame unless the <body> background should be propagated, in
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* which case we return the frame associated with the <body>'s background.
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*/
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static nsIFrame* FindBackgroundStyleFrame(nsIFrame* aForFrame);
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/**
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* @return true if |aFrame| is a canvas frame, in the CSS sense.
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*/
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static bool IsCanvasFrame(nsIFrame* aFrame);
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/**
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* Fill in an aBackgroundSC to be used to paint the background
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* for an element. This applies the rules for propagating
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* backgrounds between BODY, the root element, and the canvas.
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* @return true if there is some meaningful background.
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*/
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static bool FindBackground(nsPresContext* aPresContext,
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nsIFrame* aForFrame,
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nsStyleContext** aBackgroundSC);
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/**
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* As FindBackground, but the passed-in frame is known to be a root frame
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* (returned from nsCSSFrameConstructor::GetRootElementStyleFrame())
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* and there is always some meaningful background returned.
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*/
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static nsStyleContext* FindRootFrameBackground(nsIFrame* aForFrame);
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/**
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* Returns background style information for the canvas.
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*
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* @param aForFrame
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* the frame used to represent the canvas, in the CSS sense (i.e.
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* nsCSSRendering::IsCanvasFrame(aForFrame) must be true)
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* @param aRootElementFrame
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* the frame representing the root element of the document
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* @param aBackground
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* contains background style information for the canvas on return
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*/
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static nsStyleContext*
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FindCanvasBackground(nsIFrame* aForFrame, nsIFrame* aRootElementFrame)
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{
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NS_ABORT_IF_FALSE(IsCanvasFrame(aForFrame), "not a canvas frame");
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if (aRootElementFrame)
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return FindRootFrameBackground(aRootElementFrame);
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// This should always give transparent, so we'll fill it in with the
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// default color if needed. This seems to happen a bit while a page is
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// being loaded.
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return aForFrame->GetStyleContext();
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}
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/**
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* Find a frame which draws a non-transparent background,
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* for various table-related and HR-related backwards-compatibility hacks.
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* This function will also stop if it finds themed frame which might draw
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* background.
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*
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* Be very hesitant if you're considering calling this function -- it's
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* usually not what you want.
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*/
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static nsIFrame*
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FindNonTransparentBackgroundFrame(nsIFrame* aFrame,
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bool aStartAtParent = false);
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/**
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* Determine the background color to draw taking into account print settings.
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*/
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static nscolor
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DetermineBackgroundColor(nsPresContext* aPresContext,
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nsStyleContext* aStyleContext,
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nsIFrame* aFrame,
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bool& aDrawBackgroundImage,
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bool& aDrawBackgroundColor);
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static nsBackgroundLayerState
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PrepareBackgroundLayer(nsPresContext* aPresContext,
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nsIFrame* aForFrame,
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PRUint32 aFlags,
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const nsRect& aBorderArea,
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const nsRect& aBGClipRect,
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const nsStyleBackground& aBackground,
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const nsStyleBackground::Layer& aLayer);
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/**
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* Render the background for an element using css rendering rules
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* for backgrounds.
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*/
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enum {
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/**
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* When this flag is passed, the element's nsDisplayBorder will be
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* painted immediately on top of this background.
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*/
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PAINTBG_WILL_PAINT_BORDER = 0x01,
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/**
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* When this flag is passed, images are synchronously decoded.
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*/
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PAINTBG_SYNC_DECODE_IMAGES = 0x02,
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/**
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* When this flag is passed, painting will go to the screen so we can
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* take advantage of the fact that it will be clipped to the viewport.
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*/
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PAINTBG_TO_WINDOW = 0x04
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};
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static void PaintBackground(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aDirtyRect,
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const nsRect& aBorderArea,
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PRUint32 aFlags,
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nsRect* aBGClipRect = nullptr);
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/**
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* Same as |PaintBackground|, except using the provided style structs.
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* This short-circuits the code that ensures that the root element's
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* background is drawn on the canvas.
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*/
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static void PaintBackgroundWithSC(nsPresContext* aPresContext,
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nsRenderingContext& aRenderingContext,
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nsIFrame* aForFrame,
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const nsRect& aDirtyRect,
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const nsRect& aBorderArea,
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nsStyleContext *aStyleContext,
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const nsStyleBorder& aBorder,
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PRUint32 aFlags,
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nsRect* aBGClipRect = nullptr);
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/**
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* Returns the rectangle covered by the given background layer image, taking
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* into account background positioning, sizing, and repetition, but not
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* clipping.
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*/
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static nsRect GetBackgroundLayerRect(nsPresContext* aPresContext,
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nsIFrame* aForFrame,
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const nsRect& aBorderArea,
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const nsStyleBackground& aBackground,
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const nsStyleBackground::Layer& aLayer);
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/**
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* Called by the presShell when painting is finished, so we can clear our
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* inline background data cache.
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*/
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static void DidPaint();
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// Draw a border segment in the table collapsing border model without
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// beveling corners
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static void DrawTableBorderSegment(nsRenderingContext& aContext,
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PRUint8 aBorderStyle,
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nscolor aBorderColor,
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const nsStyleBackground* aBGColor,
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const nsRect& aBorderRect,
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PRInt32 aAppUnitsPerCSSPixel,
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PRUint8 aStartBevelSide = 0,
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nscoord aStartBevelOffset = 0,
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PRUint8 aEndBevelSide = 0,
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nscoord aEndBevelOffset = 0);
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/**
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* Function for painting the decoration lines for the text.
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* NOTE: aPt, aLineSize, aAscent and aOffset are non-rounded device pixels,
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* not app units.
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* input:
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* @param aFrame the frame which needs the decoration line
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* @param aGfxContext
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* @param aDirtyRect no need to paint outside this rect
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* @param aColor the color of the decoration line
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* @param aPt the top/left edge of the text
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* @param aXInFrame the distance between aPt.x and left edge of
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* aFrame. If the decoration line is for shadow,
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* set the distance between the left edge of
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* the aFrame and the position of the text as
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* positioned without offset of the shadow.
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* @param aLineSize the width and the height of the decoration
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* line
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* @param aAscent the ascent of the text
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* @param aOffset the offset of the decoration line from
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* the baseline of the text (if the value is
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* positive, the line is lifted up)
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* @param aDecoration which line will be painted. The value can be
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* NS_STYLE_TEXT_DECORATION_LINE_UNDERLINE or
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* NS_STYLE_TEXT_DECORATION_LINE_OVERLINE or
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* NS_STYLE_TEXT_DECORATION_LINE_LINE_THROUGH.
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* @param aStyle the style of the decoration line such as
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* NS_STYLE_TEXT_DECORATION_STYLE_*.
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* @param aDescentLimit If aDescentLimit is zero or larger and the
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* underline overflows from the descent space,
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* the underline should be lifted up as far as
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* possible. Note that this does not mean the
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* underline never overflows from this
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* limitation. Because if the underline is
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* positioned to the baseline or upper, it causes
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* unreadability. Note that if this is zero
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* or larger, the underline rect may be shrunken
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* if it's possible. Therefore, this value is
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* used for strikeout line and overline too.
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*/
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static void PaintDecorationLine(nsIFrame* aFrame,
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gfxContext* aGfxContext,
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const gfxRect& aDirtyRect,
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const nscolor aColor,
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const gfxPoint& aPt,
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const gfxFloat aXInFrame,
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const gfxSize& aLineSize,
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const gfxFloat aAscent,
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const gfxFloat aOffset,
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const PRUint8 aDecoration,
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const PRUint8 aStyle,
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const gfxFloat aDescentLimit = -1.0);
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/**
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* Adds a path corresponding to the outline of the decoration line to
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* the specified context. Arguments have the same meaning as for
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* PaintDecorationLine. Currently this only works for solid
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* decorations; for other decoration styles, an empty path is added
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* to the context.
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*/
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static void DecorationLineToPath(nsIFrame* aFrame,
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gfxContext* aGfxContext,
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const gfxRect& aDirtyRect,
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const nscolor aColor,
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const gfxPoint& aPt,
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const gfxFloat aXInFrame,
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const gfxSize& aLineSize,
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const gfxFloat aAscent,
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const gfxFloat aOffset,
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const PRUint8 aDecoration,
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const PRUint8 aStyle,
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const gfxFloat aDescentLimit = -1.0);
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/**
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* Function for getting the decoration line rect for the text.
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* NOTE: aLineSize, aAscent and aOffset are non-rounded device pixels,
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* not app units.
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* input:
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* @param aPresContext
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* @param aLineSize the width and the height of the decoration
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* line
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* @param aAscent the ascent of the text
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* @param aOffset the offset of the decoration line from
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* the baseline of the text (if the value is
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* positive, the line is lifted up)
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* @param aDecoration which line will be painted. The value can be
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* NS_STYLE_TEXT_DECORATION_LINE_UNDERLINE or
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* NS_STYLE_TEXT_DECORATION_LINE_OVERLINE or
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* NS_STYLE_TEXT_DECORATION_LINE_LINE_THROUGH.
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* @param aStyle the style of the decoration line such as
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* NS_STYLE_TEXT_DECORATION_STYLE_*.
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* @param aDescentLimit If aDescentLimit is zero or larger and the
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* underline overflows from the descent space,
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* the underline should be lifted up as far as
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* possible. Note that this does not mean the
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* underline never overflows from this
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* limitation. Because if the underline is
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* positioned to the baseline or upper, it causes
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* unreadability. Note that if this is zero
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* or larger, the underline rect may be shrunken
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* if it's possible. Therefore, this value is
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* used for strikeout line and overline too.
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* output:
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* @return the decoration line rect for the input,
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* the each values are app units.
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*/
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static nsRect GetTextDecorationRect(nsPresContext* aPresContext,
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const gfxSize& aLineSize,
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const gfxFloat aAscent,
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const gfxFloat aOffset,
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const PRUint8 aDecoration,
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const PRUint8 aStyle,
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const gfxFloat aDescentLimit = -1.0);
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protected:
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static gfxRect GetTextDecorationRectInternal(const gfxPoint& aPt,
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const gfxSize& aLineSize,
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const gfxFloat aAscent,
|
|
const gfxFloat aOffset,
|
|
const PRUint8 aDecoration,
|
|
const PRUint8 aStyle,
|
|
const gfxFloat aDscentLimit);
|
|
|
|
/**
|
|
* Returns inflated rect for painting a decoration line.
|
|
* Complex style decoration lines should be painted from leftmost of nearest
|
|
* ancestor block box because that makes better look of connection of lines
|
|
* for different nodes. ExpandPaintingRectForDecorationLine() returns
|
|
* a rect for actual painting rect for the clipped rect.
|
|
*
|
|
* input:
|
|
* @param aFrame the frame which needs the decoration line.
|
|
* @param aStyle the style of the complex decoration line
|
|
* NS_STYLE_TEXT_DECORATION_STYLE_DOTTED or
|
|
* NS_STYLE_TEXT_DECORATION_STYLE_DASHED or
|
|
* NS_STYLE_TEXT_DECORATION_STYLE_WAVY.
|
|
* @param aClippedRect the clipped rect for the decoration line.
|
|
* in other words, visible area of the line.
|
|
* @param aXInFrame the distance between left edge of aFrame and
|
|
* aClippedRect.pos.x.
|
|
* @param aCycleLength the width of one cycle of the line style.
|
|
*/
|
|
static gfxRect ExpandPaintingRectForDecorationLine(
|
|
nsIFrame* aFrame,
|
|
const PRUint8 aStyle,
|
|
const gfxRect &aClippedRect,
|
|
const gfxFloat aXInFrame,
|
|
const gfxFloat aCycleLength);
|
|
};
|
|
|
|
/*
|
|
* nsContextBoxBlur
|
|
* Creates an 8-bit alpha channel context for callers to draw in, blurs the
|
|
* contents of that context and applies it as a 1-color mask on a
|
|
* different existing context. Uses gfxAlphaBoxBlur as its back end.
|
|
*
|
|
* You must call Init() first to create a suitable temporary surface to draw
|
|
* on. You must then draw any desired content onto the given context, then
|
|
* call DoPaint() to apply the blurred content as a single-color mask. You
|
|
* can only call Init() once, so objects cannot be reused.
|
|
*
|
|
* This is very useful for creating drop shadows or silhouettes.
|
|
*/
|
|
class nsContextBoxBlur {
|
|
public:
|
|
enum {
|
|
FORCE_MASK = 0x01
|
|
};
|
|
/**
|
|
* Prepares a gfxContext to draw on. Do not call this twice; if you want
|
|
* to get the gfxContext again use GetContext().
|
|
*
|
|
* @param aRect The coordinates of the surface to create.
|
|
* All coordinates must be in app units.
|
|
* This must not include the blur radius, pass
|
|
* it as the second parameter and everything
|
|
* is taken care of.
|
|
*
|
|
* @param aBlurRadius The blur radius in app units.
|
|
*
|
|
* @param aAppUnitsPerDevPixel The number of app units in a device pixel,
|
|
* for conversion. Most of the time you'll
|
|
* pass this from the current PresContext if
|
|
* available.
|
|
*
|
|
* @param aDestinationCtx The graphics context to apply the blurred
|
|
* mask to when you call DoPaint(). Make sure
|
|
* it is not destroyed before you call
|
|
* DoPaint(). To set the color of the
|
|
* resulting blurred graphic mask, you must
|
|
* set the color on this context before
|
|
* calling Init().
|
|
*
|
|
* @param aDirtyRect The absolute dirty rect in app units. Used to
|
|
* optimize the temporary surface size and speed up blur.
|
|
*
|
|
* @param aSkipRect An area in device pixels (NOT app units!) to avoid
|
|
* blurring over, to prevent unnecessary work.
|
|
*
|
|
* @param aFlags FORCE_MASK to ensure that the content drawn to the
|
|
* returned gfxContext is used as a mask, and not
|
|
* drawn directly to aDestinationCtx.
|
|
*
|
|
* @return A blank 8-bit alpha-channel-only graphics context to
|
|
* draw on, or null on error. Must not be freed. The
|
|
* context has a device offset applied to it given by
|
|
* aRect. This means you can use coordinates as if it
|
|
* were at the desired position at aRect and you don't
|
|
* need to worry about translating any coordinates to
|
|
* draw on this temporary surface.
|
|
*
|
|
* If aBlurRadius is 0, the returned context is aDestinationCtx and
|
|
* DoPaint() does nothing, because no blurring is required. Therefore, you
|
|
* should prepare the destination context as if you were going to draw
|
|
* directly on it instead of any temporary surface created in this class.
|
|
*/
|
|
gfxContext* Init(const nsRect& aRect, nscoord aSpreadRadius,
|
|
nscoord aBlurRadius,
|
|
PRInt32 aAppUnitsPerDevPixel, gfxContext* aDestinationCtx,
|
|
const nsRect& aDirtyRect, const gfxRect* aSkipRect,
|
|
PRUint32 aFlags = 0);
|
|
|
|
/**
|
|
* Does the actual blurring/spreading. Users of this object *must*
|
|
* have called Init() first, then have drawn whatever they want to be
|
|
* blurred onto the internal gfxContext before calling this.
|
|
*/
|
|
void DoEffects();
|
|
|
|
/**
|
|
* Does the actual blurring and mask applying. Users of this object *must*
|
|
* have called Init() first, then have drawn whatever they want to be
|
|
* blurred onto the internal gfxContext before calling this.
|
|
*/
|
|
void DoPaint();
|
|
|
|
/**
|
|
* Gets the internal gfxContext at any time. Must not be freed. Avoid
|
|
* calling this before calling Init() since the context would not be
|
|
* constructed at that point.
|
|
*/
|
|
gfxContext* GetContext();
|
|
|
|
|
|
/**
|
|
* Get the margin associated with the given blur radius, i.e., the
|
|
* additional area that might be painted as a result of it. (The
|
|
* margin for a spread radius is itself, on all sides.)
|
|
*/
|
|
static nsMargin GetBlurRadiusMargin(nscoord aBlurRadius,
|
|
PRInt32 aAppUnitsPerDevPixel);
|
|
|
|
protected:
|
|
gfxAlphaBoxBlur blur;
|
|
nsRefPtr<gfxContext> mContext;
|
|
gfxContext* mDestinationCtx;
|
|
|
|
/* This is true if the blur already has it's content transformed
|
|
* by mDestinationCtx's transform */
|
|
bool mPreTransformed;
|
|
|
|
};
|
|
|
|
#endif /* nsCSSRendering_h___ */
|