gecko-dev/layout/svg/nsSVGUtils.h

586 строки
20 KiB
C++

/* -*- 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 NS_SVGUTILS_H
#define NS_SVGUTILS_H
// include math.h to pick up definition of M_ maths defines e.g. M_PI
#include <math.h>
#include "DrawMode.h"
#include "gfx2DGlue.h"
#include "gfxMatrix.h"
#include "gfxPoint.h"
#include "gfxRect.h"
#include "mozilla/gfx/Rect.h"
#include "nsAlgorithm.h"
#include "nsChangeHint.h"
#include "nsColor.h"
#include "nsCOMPtr.h"
#include "nsID.h"
#include "nsIFrame.h"
#include "nsISupportsBase.h"
#include "nsMathUtils.h"
#include "nsStyleStruct.h"
#include <algorithm>
class gfxContext;
class nsFrameList;
class nsIContent;
class nsIDocument;
class nsIFrame;
class nsPresContext;
class nsStyleContext;
class nsSVGDisplayContainerFrame;
class nsSVGElement;
class nsSVGEnum;
class nsSVGLength2;
class nsSVGOuterSVGFrame;
class nsSVGPathGeometryFrame;
class nsTextFrame;
class gfxTextContextPaint;
struct nsStyleSVG;
struct nsStyleSVGPaint;
struct nsRect;
namespace mozilla {
namespace dom {
class Element;
class UserSpaceMetrics;
} // namespace dom
namespace gfx {
class DrawTarget;
class GeneralPattern;
} // namespace gfx
} // namespace mozilla
// maximum dimension of an offscreen surface - choose so that
// the surface size doesn't overflow a 32-bit signed int using
// 4 bytes per pixel; in line with gfxASurface::CheckSurfaceSize
// In fact Macs can't even manage that
#define NS_SVG_OFFSCREEN_MAX_DIMENSION 4096
#define SVG_HIT_TEST_FILL 0x01
#define SVG_HIT_TEST_STROKE 0x02
#define SVG_HIT_TEST_CHECK_MRECT 0x04
bool NS_SVGPathCachingEnabled();
bool NS_SVGDisplayListHitTestingEnabled();
bool NS_SVGDisplayListPaintingEnabled();
bool NS_SVGNewGetBBoxEnabled();
/**
* Sometimes we need to distinguish between an empty box and a box
* that contains an element that has no size e.g. a point at the origin.
*/
class SVGBBox {
typedef mozilla::gfx::Rect Rect;
public:
SVGBBox()
: mIsEmpty(true) {}
MOZ_IMPLICIT SVGBBox(const Rect& aRect)
: mBBox(aRect), mIsEmpty(false) {}
MOZ_IMPLICIT SVGBBox(const gfxRect& aRect)
: mBBox(ToRect(aRect)), mIsEmpty(false) {}
gfxRect ToThebesRect() const {
return ThebesRect(mBBox);
}
bool IsEmpty() const {
return mIsEmpty;
}
bool IsFinite() const {
return mBBox.IsFinite();
}
void Scale(float aScale) {
mBBox.Scale(aScale);
}
void UnionEdges(const SVGBBox& aSVGBBox) {
if (aSVGBBox.mIsEmpty) {
return;
}
mBBox = mIsEmpty ? aSVGBBox.mBBox : mBBox.UnionEdges(aSVGBBox.mBBox);
mIsEmpty = false;
}
void Intersect(const SVGBBox& aSVGBBox) {
if (!mIsEmpty && !aSVGBBox.mIsEmpty) {
mBBox = mBBox.Intersect(aSVGBBox.mBBox);
if (mBBox.IsEmpty()) {
mIsEmpty = true;
mBBox = Rect(0, 0, 0, 0);
}
} else {
mIsEmpty = true;
mBBox = Rect(0, 0, 0, 0);
}
}
private:
Rect mBBox;
bool mIsEmpty;
};
// GRRR WINDOWS HATE HATE HATE
#undef CLIP_MASK
class MOZ_RAII SVGAutoRenderState
{
typedef mozilla::gfx::DrawTarget DrawTarget;
public:
explicit SVGAutoRenderState(DrawTarget* aDrawTarget
MOZ_GUARD_OBJECT_NOTIFIER_PARAM);
~SVGAutoRenderState();
void SetPaintingToWindow(bool aPaintingToWindow);
static bool IsPaintingToWindow(DrawTarget* aDrawTarget);
private:
DrawTarget* mDrawTarget;
void* mOriginalRenderState;
bool mPaintingToWindow;
MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
};
#define NS_ISVGFILTERREFERENCE_IID \
{ 0x9744ee20, 0x1bcf, 0x4c62, \
{ 0x86, 0x7d, 0xd3, 0x7a, 0x91, 0x60, 0x3e, 0xef } }
class nsISVGFilterReference : public nsISupports
{
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_ISVGFILTERREFERENCE_IID)
virtual void Invalidate() = 0;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsISVGFilterReference, NS_ISVGFILTERREFERENCE_IID)
/**
* General functions used by all of SVG layout and possibly content code.
* If a method is used by content and depends only on other content methods
* it should go in SVGContentUtils instead.
*/
class nsSVGUtils
{
public:
typedef mozilla::dom::Element Element;
typedef mozilla::FramePropertyDescriptor FramePropertyDescriptor;
typedef mozilla::gfx::AntialiasMode AntialiasMode;
typedef mozilla::gfx::FillRule FillRule;
typedef mozilla::gfx::GeneralPattern GeneralPattern;
typedef mozilla::gfx::Size Size;
static void Init();
static void DestroyObjectBoundingBoxProperty(void* aPropertyValue) {
delete static_cast<gfxRect*>(aPropertyValue);
}
NS_DECLARE_FRAME_PROPERTY(ObjectBoundingBoxProperty,
DestroyObjectBoundingBoxProperty);
/**
* Gets the nearest nsSVGInnerSVGFrame or nsSVGOuterSVGFrame frame. aFrame
* must be an SVG frame. If aFrame is of type nsGkAtoms::svgOuterSVGFrame,
* returns nullptr.
*/
static nsSVGDisplayContainerFrame* GetNearestSVGViewport(nsIFrame *aFrame);
/**
* Returns the frame's post-filter visual overflow rect when passed the
* frame's pre-filter visual overflow rect. If the frame is not currently
* being filtered, this function simply returns aUnfilteredRect.
*/
static nsRect GetPostFilterVisualOverflowRect(nsIFrame *aFrame,
const nsRect &aUnfilteredRect);
/**
* Schedules an update of the frame's bounds (which will in turn invalidate
* the new area that the frame should paint to).
*
* This does nothing when passed an NS_FRAME_IS_NONDISPLAY frame.
* In future we may want to allow ReflowSVG to be called on such frames,
* but that would be better implemented as a ForceReflowSVG function to
* be called synchronously while painting them without marking or paying
* attention to dirty bits like this function.
*
* This is very similar to PresShell::FrameNeedsReflow. The main reason that
* we have this function instead of using FrameNeedsReflow is because we need
* to be able to call it under nsSVGOuterSVGFrame::NotifyViewportChange when
* that function is called by nsSVGOuterSVGFrame::Reflow. FrameNeedsReflow
* is not suitable for calling during reflow though, and it asserts as much.
* The reason that we want to be callable under NotifyViewportChange is
* because we want to synchronously notify and dirty the nsSVGOuterSVGFrame's
* children so that when nsSVGOuterSVGFrame::DidReflow is called its children
* will be updated for the new size as appropriate. Otherwise we'd have to
* post an event to the event loop to mark dirty flags and request an update.
*
* Another reason that we don't currently want to call
* PresShell::FrameNeedsReflow is because passing eRestyle to it to get it to
* mark descendants dirty would cause it to descend through
* nsSVGForeignObjectFrame frames to mark their children dirty, but we want to
* handle nsSVGForeignObjectFrame specially. It would also do unnecessary work
* descending into NS_FRAME_IS_NONDISPLAY frames.
*/
static void ScheduleReflowSVG(nsIFrame *aFrame);
/**
* Returns true if the frame or any of its children need ReflowSVG
* to be called on them.
*/
static bool NeedsReflowSVG(nsIFrame *aFrame);
/*
* Update the filter invalidation region for ancestor frames, if relevant.
*/
static void NotifyAncestorsOfFilterRegionChange(nsIFrame *aFrame);
/**
* Percentage lengths in SVG are resolved against the width/height of the
* nearest viewport (or its viewBox, if set). This helper returns the size
* of this "context" for the given frame so that percentage values can be
* resolved.
*/
static Size GetContextSize(const nsIFrame* aFrame);
/* Computes the input length in terms of object space coordinates.
Input: rect - bounding box
length - length to be converted
*/
static float ObjectSpace(const gfxRect &aRect, const nsSVGLength2 *aLength);
/* Computes the input length in terms of user space coordinates.
Input: content - object to be used for determining user space
Input: length - length to be converted
*/
static float UserSpace(nsSVGElement *aSVGElement, const nsSVGLength2 *aLength);
static float UserSpace(nsIFrame *aFrame, const nsSVGLength2 *aLength);
static float UserSpace(const mozilla::dom::UserSpaceMetrics& aMetrics, const nsSVGLength2 *aLength);
/* Find the outermost SVG frame of the passed frame */
static nsSVGOuterSVGFrame *
GetOuterSVGFrame(nsIFrame *aFrame);
/**
* Get the covered region for a frame. Return null if it's not an SVG frame.
* @param aRect gets a rectangle in app units
* @return the outer SVG frame which aRect is relative to
*/
static nsIFrame*
GetOuterSVGFrameAndCoveredRegion(nsIFrame* aFrame, nsRect* aRect);
/* Paint SVG frame with SVG effects - aDirtyRect is the area being
* redrawn, in device pixel coordinates relative to the outer svg */
static void
PaintFrameWithEffects(nsIFrame *aFrame,
gfxContext& aContext,
const gfxMatrix& aTransform,
const nsIntRect *aDirtyRect = nullptr);
/* Hit testing - check if point hits the clipPath of indicated
* frame. Returns true if no clipPath set. */
static bool
HitTestClip(nsIFrame *aFrame, const gfxPoint &aPoint);
/**
* Hit testing - check if point hits any children of aFrame. aPoint is
* expected to be in the coordinate space established by aFrame for its
* children (e.g. the space established by the 'viewBox' attribute on <svg>).
*/
static nsIFrame *
HitTestChildren(nsSVGDisplayContainerFrame *aFrame, const gfxPoint &aPoint);
/*
* Returns the CanvasTM of the indicated frame, whether it's a
* child SVG frame, container SVG frame, or a regular frame.
* For regular frames, we just return an identity matrix.
*/
static gfxMatrix GetCanvasTM(nsIFrame* aFrame);
/**
* Returns the transform from aFrame's user space to canvas space. Only call
* with SVG frames. This is like GetCanvasTM, except that it only includes
* the transforms from aFrame's user space (i.e. the coordinate context
* established by its 'transform' attribute, or else the coordinate context
* that its _parent_ establishes for its children) to outer-<svg> device
* space. Specifically, it does not include any other transforms introduced
* by the frame such as x/y offsets and viewBox attributes.
*/
static gfxMatrix GetUserToCanvasTM(nsIFrame* aFrame);
/**
* Notify the descendants of aFrame of a change to one of their ancestors
* that might affect them.
*/
static void
NotifyChildrenOfSVGChange(nsIFrame *aFrame, uint32_t aFlags);
/*
* Get frame's covered region by walking the children and doing union.
*/
static nsRect
GetCoveredRegion(const nsFrameList &aFrames);
static nsRect
TransformFrameRectToOuterSVG(const nsRect& aRect,
const gfxMatrix& aMatrix,
nsPresContext* aPresContext);
/*
* Convert a surface size to an integer for use by thebes
* possibly making it smaller in the process so the surface does not
* use excessive memory.
*
* @param aSize the desired surface size
* @param aResultOverflows true if the desired surface size is too big
* @return the surface size to use
*/
static mozilla::gfx::IntSize ConvertToSurfaceSize(const gfxSize& aSize,
bool *aResultOverflows);
/*
* Hit test a given rectangle/matrix.
*/
static bool
HitTestRect(const mozilla::gfx::Matrix &aMatrix,
float aRX, float aRY, float aRWidth, float aRHeight,
float aX, float aY);
/**
* Get the clip rect for the given frame, taking into account the CSS 'clip'
* property. See:
* http://www.w3.org/TR/SVG11/masking.html#OverflowAndClipProperties
* The arguments for aX, aY, aWidth and aHeight should be the dimensions of
* the viewport established by aFrame.
*/
static gfxRect
GetClipRectForFrame(nsIFrame *aFrame,
float aX, float aY, float aWidth, float aHeight);
static void SetClipRect(gfxContext *aContext,
const gfxMatrix &aCTM,
const gfxRect &aRect);
/* Using group opacity instead of fill or stroke opacity on a
* geometry object seems to be a common authoring mistake. If we're
* not applying filters and not both stroking and filling, we can
* generate the same result without going through the overhead of a
* push/pop group. */
static bool
CanOptimizeOpacity(nsIFrame *aFrame);
/**
* Take the CTM to userspace for an element, and adjust it to a CTM to its
* object bounding box space if aUnits is SVG_UNIT_TYPE_OBJECTBOUNDINGBOX.
* (I.e. so that [0,0] is at the top left of its bbox, and [1,1] is at the
* bottom right of its bbox).
*
* If the bbox is empty, this will return a singular matrix.
*/
static gfxMatrix
AdjustMatrixForUnits(const gfxMatrix &aMatrix,
nsSVGEnum *aUnits,
nsIFrame *aFrame);
enum BBoxFlags {
eBBoxIncludeFill = 1 << 0,
eBBoxIncludeFillGeometry = 1 << 1,
eBBoxIncludeStroke = 1 << 2,
eBBoxIncludeStrokeGeometry = 1 << 3,
eBBoxIncludeMarkers = 1 << 4,
eBBoxIncludeClipped = 1 << 5
};
/**
* Get the SVG bbox (the SVG spec's simplified idea of bounds) of aFrame in
* aFrame's userspace.
*/
static gfxRect GetBBox(nsIFrame *aFrame,
// If the default arg changes, update the handling for
// ObjectBoundingBoxProperty() in the implementation.
uint32_t aFlags = eBBoxIncludeFillGeometry);
/*
* "User space" is the space that the frame's BBox (as calculated by
* nsSVGUtils::GetBBox) is in. "Frame space" is the space that has its origin
* at the top left of the union of the frame's border-box rects over all
* continuations.
* This function returns the offset one needs to add to something in frame
* space in order to get its coordinates in user space.
*/
static gfxPoint FrameSpaceInCSSPxToUserSpaceOffset(nsIFrame *aFrame);
/**
* Convert a userSpaceOnUse/objectBoundingBoxUnits rectangle that's specified
* using four nsSVGLength2 values into a user unit rectangle in user space.
*
* @param aXYWH pointer to 4 consecutive nsSVGLength2 objects containing
* the x, y, width and height values in that order
* @param aBBox the bounding box of the object the rect is relative to;
* may be null if aUnits is not SVG_UNIT_TYPE_OBJECTBOUNDINGBOX
* @param aFrame the object in which to interpret user-space units;
* may be null if aUnits is SVG_UNIT_TYPE_OBJECTBOUNDINGBOX
*/
static gfxRect
GetRelativeRect(uint16_t aUnits, const nsSVGLength2 *aXYWH,
const gfxRect& aBBox, nsIFrame *aFrame);
static gfxRect
GetRelativeRect(uint16_t aUnits, const nsSVGLength2 *aXYWH,
const gfxRect& aBBox,
const mozilla::dom::UserSpaceMetrics& aMetrics);
/**
* Find the first frame, starting with aStartFrame and going up its
* parent chain, that is not an svgAFrame.
*/
static nsIFrame* GetFirstNonAAncestorFrame(nsIFrame* aStartFrame);
static bool OuterSVGIsCallingReflowSVG(nsIFrame *aFrame);
static bool AnyOuterSVGIsCallingReflowSVG(nsIFrame *aFrame);
/**
* See https://svgwg.org/svg2-draft/painting.html#NonScalingStroke
*
* If the computed value of the 'vector-effect' property on aFrame is
* 'non-scaling-stroke', then this function will set aUserToOuterSVG to the
* transform from aFrame's SVG user space to the initial coordinate system
* established by the viewport of aFrame's outer-<svg>'s (the coordinate
* system in which the stroke is fixed). If aUserToOuterSVG is set to a
* non-identity matrix this function returns true, else it returns false.
*/
static bool GetNonScalingStrokeTransform(nsIFrame *aFrame,
gfxMatrix* aUserToOuterSVG);
/**
* Compute the maximum possible device space stroke extents of a path given
* the path's device space path extents, its stroke style and its ctm.
*
* This is a workaround for the lack of suitable cairo API for getting the
* tight device space stroke extents of a path. This basically gives us the
* tightest extents that we can guarantee fully enclose the inked stroke
* without doing the calculations for the actual tight extents. We exploit
* the fact that cairo does have an API for getting the tight device space
* fill/path extents.
*
* This should die once bug 478152 is fixed.
*/
static gfxRect PathExtentsToMaxStrokeExtents(const gfxRect& aPathExtents,
nsTextFrame* aFrame,
const gfxMatrix& aMatrix);
static gfxRect PathExtentsToMaxStrokeExtents(const gfxRect& aPathExtents,
nsSVGPathGeometryFrame* aFrame,
const gfxMatrix& aMatrix);
/**
* Convert a floating-point value to a 32-bit integer value, clamping to
* the range of valid integers.
*/
static int32_t ClampToInt(double aVal)
{
return NS_lround(std::max(double(INT32_MIN),
std::min(double(INT32_MAX), aVal)));
}
static nscolor GetFallbackOrPaintColor(nsStyleContext *aStyleContext,
nsStyleSVGPaint nsStyleSVG::*aFillOrStroke);
static void
MakeFillPatternFor(nsIFrame *aFrame,
gfxContext* aContext,
GeneralPattern* aOutPattern,
gfxTextContextPaint *aContextPaint = nullptr);
static void
MakeStrokePatternFor(nsIFrame* aFrame,
gfxContext* aContext,
GeneralPattern* aOutPattern,
gfxTextContextPaint *aContextPaint = nullptr);
static float GetOpacity(nsStyleSVGOpacitySource aOpacityType,
const float& aOpacity,
gfxTextContextPaint *aContextPaint);
/*
* @return false if there is no stroke
*/
static bool HasStroke(nsIFrame* aFrame,
gfxTextContextPaint *aContextPaint = nullptr);
static float GetStrokeWidth(nsIFrame* aFrame,
gfxTextContextPaint *aContextPaint = nullptr);
/*
* Set up a cairo context for a stroked path (including any dashing that
* applies).
*/
static void SetupCairoStrokeGeometry(nsIFrame* aFrame, gfxContext *aContext,
gfxTextContextPaint *aContextPaint = nullptr);
/**
* This function returns a set of bit flags indicating which parts of the
* element (fill, stroke, bounds) should intercept pointer events. It takes
* into account the type of element and the value of the 'pointer-events'
* property on the element.
*/
static uint16_t GetGeometryHitTestFlags(nsIFrame* aFrame);
static FillRule ToFillRule(uint8_t aFillRule) {
return aFillRule == NS_STYLE_FILL_RULE_EVENODD ?
FillRule::FILL_EVEN_ODD : FillRule::FILL_WINDING;
}
static AntialiasMode ToAntialiasMode(uint8_t aTextRendering) {
return aTextRendering == NS_STYLE_TEXT_RENDERING_OPTIMIZESPEED ?
AntialiasMode::NONE : AntialiasMode::SUBPIXEL;
}
/**
* Render a SVG glyph.
* @param aElement the SVG glyph element to render
* @param aContext the thebes aContext to draw to
* @param aDrawMode fill or stroke or both (see DrawMode)
* @return true if rendering succeeded
*/
static bool PaintSVGGlyph(Element* aElement, gfxContext* aContext,
DrawMode aDrawMode,
gfxTextContextPaint* aContextPaint);
/**
* Get the extents of a SVG glyph.
* @param aElement the SVG glyph element
* @param aSVGToAppSpace the matrix mapping the SVG glyph space to the
* target context space
* @param aResult the result (valid when true is returned)
* @return true if calculating the extents succeeded
*/
static bool GetSVGGlyphExtents(Element* aElement,
const gfxMatrix& aSVGToAppSpace,
gfxRect* aResult);
/**
* Returns the app unit canvas bounds of a userspace rect.
*
* @param aToCanvas Transform from userspace to canvas device space.
*/
static nsRect
ToCanvasBounds(const gfxRect &aUserspaceRect,
const gfxMatrix &aToCanvas,
const nsPresContext *presContext);
};
#endif