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Diffstat (limited to 'layout/mathml/nsIMathMLFrame.h')
| -rw-r--r-- | layout/mathml/nsIMathMLFrame.h | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/layout/mathml/nsIMathMLFrame.h b/layout/mathml/nsIMathMLFrame.h new file mode 100644 index 0000000000..03eb412a15 --- /dev/null +++ b/layout/mathml/nsIMathMLFrame.h @@ -0,0 +1,391 @@ +/* -*- 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/. */ +// #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 + +// This bit is set when the frame cannot be formatted due to an +// error (e.g., invalid markup such as a <msup> without an overscript). +// When set, a visual feedback will be provided to the user. +#define NS_MATHML_ERROR 0x80000000U + +// 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_HAS_ERROR(_flags) \ + (NS_MATHML_ERROR == ((_flags)&NS_MATHML_ERROR)) + +#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___ */ |