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/* -*- 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
// #define SHOW_BOUNDING_BOX 1
#ifndef nsIMathMLFrame_h___
#define nsIMathMLFrame_h___
#include "nsQueryFrame.h"
#include "nsMathMLOperators.h"
struct nsPresentationData;
struct nsEmbellishData;
class gfxContext;
class nsIFrame;
namespace mozilla {
class ReflowOutput;
} // namespace mozilla
// For MathML, this 'type' will be used to determine the spacing between frames
// Subclasses can return a 'type' that will give them a particular spacing
enum eMathMLFrameType {
eMathMLFrameType_UNKNOWN = -1,
eMathMLFrameType_Ordinary,
eMathMLFrameType_OperatorOrdinary,
eMathMLFrameType_OperatorInvisible,
eMathMLFrameType_OperatorUserDefined,
eMathMLFrameType_Inner,
eMathMLFrameType_ItalicIdentifier,
eMathMLFrameType_UprightIdentifier,
eMathMLFrameType_COUNT
};
// Abstract base class that provides additional methods for MathML frames
class nsIMathMLFrame {
public:
NS_DECL_QUERYFRAME_TARGET(nsIMathMLFrame)
// helper to check whether the frame is "space-like", as defined by the spec.
virtual bool IsSpaceLike() = 0;
/* SUPPORT FOR PRECISE POSITIONING */
/*====================================================================*/
/* Metrics that _exactly_ enclose the text of the frame.
* The frame *must* have *already* being reflowed, before you can call
* the GetBoundingMetrics() method.
* Note that for a frame with nested children, the bounding metrics
* will exactly enclose its children. For example, the bounding metrics
* of msub is the smallest rectangle that exactly encloses both the
* base and the subscript.
*/
NS_IMETHOD
GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics) = 0;
NS_IMETHOD
SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics) = 0;
NS_IMETHOD
SetReference(const nsPoint& aReference) = 0;
virtual eMathMLFrameType GetMathMLFrameType() = 0;
/* SUPPORT FOR STRETCHY ELEMENTS */
/*====================================================================*/
/* Stretch :
* Called to ask a stretchy MathML frame to stretch itself depending
* on its context.
*
* An embellished frame is treated in a special way. When it receives a
* Stretch() command, it passes the command to its embellished child and
* the stretched size is bubbled up from the inner-most <mo> frame. In other
* words, the stretch command descend through the embellished hierarchy.
*
* @param aStretchDirection [in] the direction where to attempt to
* stretch.
* @param aContainerSize [in] struct that suggests the maximumn size for
* the stretched frame. Only member data of the struct that are
* relevant to the direction are used (the rest is ignored).
* @param aDesiredStretchSize [in/out] On input the current size
* of the frame, on output the size after stretching.
*/
NS_IMETHOD
Stretch(mozilla::gfx::DrawTarget* aDrawTarget,
nsStretchDirection aStretchDirection,
nsBoundingMetrics& aContainerSize,
mozilla::ReflowOutput& aDesiredStretchSize) = 0;
/* Get the mEmbellishData member variable. */
NS_IMETHOD
GetEmbellishData(nsEmbellishData& aEmbellishData) = 0;
/* SUPPORT FOR SCRIPTING ELEMENTS */
/*====================================================================*/
/* Get the mPresentationData member variable. */
NS_IMETHOD
GetPresentationData(nsPresentationData& aPresentationData) = 0;
/* InheritAutomaticData() / TransmitAutomaticData() :
* There are precise rules governing each MathML frame and its children.
* Properties such as the scriptlevel or the embellished nature of a frame
* depend on those rules. Also, certain properties that we use to emulate
* TeX rendering rules are frame-dependent too. These two methods are meant
* to be implemented by frame classes that need to assert specific properties
* within their subtrees.
*
* InheritAutomaticData() is called in a top-down manner [like
* nsIFrame::Init], as we descend the frame tree, whereas
* TransmitAutomaticData() is called in a bottom-up manner, as we ascend the
* tree [like nsIFrame::SetInitialChildList]. However, unlike Init() and
* SetInitialChildList() which are called only once during the life-time of a
* frame (when initially constructing the frame tree), these two methods are
* called to build automatic data after the <math>...</math> subtree has been
* constructed fully, and are called again as we walk a child's subtree to
* handle dynamic changes that happen in the content model.
*
* As a rule of thumb:
*
* 1. Use InheritAutomaticData() to set properties related to your ancestors:
* - set properties that are intrinsic to yourself
* - set properties that depend on the state that you expect your ancestors
* to have already reached in their own InheritAutomaticData().
* - set properties that your descendants assume that you would have set in
* your InheritAutomaticData() -- this way, they can safely query them
* and the process will feed upon itself.
*
* 2. Use TransmitAutomaticData() to set properties related to your
* descendants:
* - set properties that depend on the state that you expect your
* descendants to have reached upon processing their own
* TransmitAutomaticData().
* - transmit properties that your descendants expect that you will
* transmit to them in your TransmitAutomaticData() -- this way, they
* remain up-to-date.
* - set properties that your ancestors expect that you would set in your
* TransmitAutomaticData() -- this way, they can safely query them and
* the process will feed upon itself.
*/
NS_IMETHOD
InheritAutomaticData(nsIFrame* aParent) = 0;
NS_IMETHOD
TransmitAutomaticData() = 0;
/* UpdatePresentationData:
* Updates the frame's compression flag.
* A frame becomes "compressed" (or "cramped") according to TeX rendering
* rules (TeXBook, Ch.17, p.140-141).
*
* @param aFlagsValues [in]
* The new values (e.g., compress) that are going to be
* updated.
*
* @param aWhichFlags [in]
* The flags that are relevant to this call. Since not all calls
* are meant to update all flags at once, aWhichFlags is used
* to distinguish flags that need to retain their existing values
* from flags that need to be turned on (or turned off). If a bit
* is set in aWhichFlags, then the corresponding value (which
* can be 0 or 1) is taken from aFlagsValues and applied to the
* frame. Therefore, by setting their bits in aWhichFlags, and
* setting their desired values in aFlagsValues, it is possible to
* update some flags in the frame, leaving the other flags unchanged.
*/
NS_IMETHOD
UpdatePresentationData(uint32_t aFlagsValues, uint32_t aWhichFlags) = 0;
/* UpdatePresentationDataFromChildAt :
* Sets compression flag on the whole tree. For child frames
* at aFirstIndex up to aLastIndex, this method sets their
* compression flags. The update is propagated down the subtrees of each of
* these child frames.
*
* @param aFirstIndex [in]
* Index of the first child from where the update is propagated.
*
* @param aLastIndex [in]
* Index of the last child where to stop the update.
* A value of -1 means up to last existing child.
*
* @param aFlagsValues [in]
* The new values (e.g., compress) that are going to be
* assigned in the whole sub-trees.
*
* @param aWhichFlags [in]
* The flags that are relevant to this call. See
* UpdatePresentationData() for more details about this parameter.
*/
NS_IMETHOD
UpdatePresentationDataFromChildAt(int32_t aFirstIndex, int32_t aLastIndex,
uint32_t aFlagsValues,
uint32_t aWhichFlags) = 0;
// If aFrame is a child frame, returns the script increment which this frame
// imposes on the specified frame, ignoring any artificial adjustments to
// scriptlevel.
// Returns 0 if the specified frame isn't a child frame.
virtual uint8_t ScriptIncrement(nsIFrame* aFrame) = 0;
// Returns true if the frame is considered to be an mrow for layout purposes.
// This includes inferred mrows, but excludes <mrow> elements with a single
// child. In the latter case, the child is to be treated as if it wasn't
// within an mrow, so we pretend the mrow isn't mrow-like.
virtual bool IsMrowLike() = 0;
};
// struct used by a container frame to keep track of its embellishments.
// By convention, the data that we keep here is bubbled from the embellished
// hierarchy, and it remains unchanged unless we have to recover from a change
// that occurs in the embellished hierarchy. The struct remains in its nil
// state in those frames that are not part of the embellished hierarchy.
struct nsEmbellishData {
// bits used to mark certain properties of our embellishments
uint32_t flags;
// pointer on the <mo> frame at the core of the embellished hierarchy
nsIFrame* coreFrame;
// stretchy direction that the nsMathMLChar owned by the core <mo> supports
nsStretchDirection direction;
// spacing that may come from <mo> depending on its 'form'. Since
// the 'form' may also depend on the position of the outermost
// embellished ancestor, the set up of these values may require
// looking up the position of our ancestors.
nscoord leadingSpace;
nscoord trailingSpace;
nsEmbellishData() {
flags = 0;
coreFrame = nullptr;
direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
leadingSpace = 0;
trailingSpace = 0;
}
};
// struct used by a container frame to modulate its presentation.
// By convention, the data that we keep in this struct can change depending
// on any of our ancestors and/or descendants. If a data can be resolved
// solely from the embellished hierarchy, and it remains immutable once
// resolved, we put it in |nsEmbellishData|. If it can be affected by other
// things, it comes here. This struct is updated as we receive information
// transmitted by our ancestors and is kept in sync with changes in our
// descendants that affects us.
struct nsPresentationData {
// bits for: compressed, etc
uint32_t flags;
// handy pointer on our base child (the 'nucleus' in TeX), but it may be
// null here (e.g., tags like <mrow>, <mfrac>, <mtable>, etc, won't
// pick a particular child in their child list to be the base)
nsIFrame* baseFrame;
nsPresentationData() {
flags = 0;
baseFrame = nullptr;
}
};
// ==========================================================================
// Bits used for the presentation flags -- these bits are set
// in their relevant situation as they become available
// This bit is used to emulate TeX rendering.
// Internal use only, cannot be set by the user with an attribute.
#define NS_MATHML_COMPRESSED 0x00000002U
// This bit is set if the frame will fire a vertical stretch
// command on all its (non-empty) children.
// Tags like <mrow> (or an inferred mrow), mpadded, etc, will fire a
// vertical stretch command on all their non-empty children
#define NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY 0x00000004U
// This bit is set if the frame will fire a horizontal stretch
// command on all its (non-empty) children.
// Tags like munder, mover, munderover, will fire a
// horizontal stretch command on all their non-empty children
#define NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY 0x00000008U
// This bit is set if the frame is "space-like", as defined by the spec.
#define NS_MATHML_SPACE_LIKE 0x00000040U
// This bit is set if a token frame should be rendered with the dtls font
// feature setting.
#define NS_MATHML_DTLS 0x00000080U
// a bit used for debug
#define NS_MATHML_STRETCH_DONE 0x20000000U
// This bit is used for visual debug. When set, the bounding box
// of your frame is painted. This visual debug enable to ensure that
// you have properly filled your mReference and mBoundingMetrics in
// Place().
#define NS_MATHML_SHOW_BOUNDING_METRICS 0x10000000U
// Macros that retrieve those bits
#define NS_MATHML_IS_COMPRESSED(_flags) \
(NS_MATHML_COMPRESSED == ((_flags) & NS_MATHML_COMPRESSED))
#define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(_flags) \
(NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY == \
((_flags) & NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY))
#define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(_flags) \
(NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY == \
((_flags) & NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY))
#define NS_MATHML_IS_SPACE_LIKE(_flags) \
(NS_MATHML_SPACE_LIKE == ((_flags) & NS_MATHML_SPACE_LIKE))
#define NS_MATHML_IS_DTLS_SET(_flags) \
(NS_MATHML_DTLS == ((_flags) & NS_MATHML_DTLS))
#define NS_MATHML_STRETCH_WAS_DONE(_flags) \
(NS_MATHML_STRETCH_DONE == ((_flags) & NS_MATHML_STRETCH_DONE))
#define NS_MATHML_PAINT_BOUNDING_METRICS(_flags) \
(NS_MATHML_SHOW_BOUNDING_METRICS == \
((_flags) & NS_MATHML_SHOW_BOUNDING_METRICS))
// ==========================================================================
// Bits used for the embellish flags -- these bits are set
// in their relevant situation as they become available
// This bit is set if the frame is an embellished operator.
#define NS_MATHML_EMBELLISH_OPERATOR 0x00000001
// This bit is set if the frame is an <mo> frame or an embellihsed
// operator for which the core <mo> has movablelimits="true"
#define NS_MATHML_EMBELLISH_MOVABLELIMITS 0x00000002
// This bit is set if the frame is an <mo> frame or an embellihsed
// operator for which the core <mo> has accent="true"
#define NS_MATHML_EMBELLISH_ACCENT 0x00000004
// This bit is set if the frame is an <mover> or <munderover> with
// an accent frame
#define NS_MATHML_EMBELLISH_ACCENTOVER 0x00000008
// This bit is set if the frame is an <munder> or <munderover> with
// an accentunder frame
#define NS_MATHML_EMBELLISH_ACCENTUNDER 0x00000010
// This bit is set on the core if it is a fence operator.
#define NS_MATHML_EMBELLISH_FENCE 0x00000020
// This bit is set on the core if it is a separator operator.
#define NS_MATHML_EMBELLISH_SEPARATOR 0x00000040
// Macros that retrieve those bits
#define NS_MATHML_IS_EMBELLISH_OPERATOR(_flags) \
(NS_MATHML_EMBELLISH_OPERATOR == ((_flags) & NS_MATHML_EMBELLISH_OPERATOR))
#define NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(_flags) \
(NS_MATHML_EMBELLISH_MOVABLELIMITS == \
((_flags) & NS_MATHML_EMBELLISH_MOVABLELIMITS))
#define NS_MATHML_EMBELLISH_IS_ACCENT(_flags) \
(NS_MATHML_EMBELLISH_ACCENT == ((_flags) & NS_MATHML_EMBELLISH_ACCENT))
#define NS_MATHML_EMBELLISH_IS_ACCENTOVER(_flags) \
(NS_MATHML_EMBELLISH_ACCENTOVER == \
((_flags) & NS_MATHML_EMBELLISH_ACCENTOVER))
#define NS_MATHML_EMBELLISH_IS_ACCENTUNDER(_flags) \
(NS_MATHML_EMBELLISH_ACCENTUNDER == \
((_flags) & NS_MATHML_EMBELLISH_ACCENTUNDER))
#define NS_MATHML_EMBELLISH_IS_FENCE(_flags) \
(NS_MATHML_EMBELLISH_FENCE == ((_flags) & NS_MATHML_EMBELLISH_FENCE))
#define NS_MATHML_EMBELLISH_IS_SEPARATOR(_flags) \
(NS_MATHML_EMBELLISH_SEPARATOR == ((_flags) & NS_MATHML_EMBELLISH_SEPARATOR))
#endif /* nsIMathMLFrame_h___ */