1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/mathml/nsIMathMLFrame.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,366 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +//#define SHOW_BOUNDING_BOX 1
1.9 +#ifndef nsIMathMLFrame_h___
1.10 +#define nsIMathMLFrame_h___
1.11 +
1.12 +#include "nsQueryFrame.h"
1.13 +#include "nsMathMLOperators.h"
1.14 +
1.15 +struct nsPresentationData;
1.16 +struct nsEmbellishData;
1.17 +struct nsHTMLReflowMetrics;
1.18 +class nsRenderingContext;
1.19 +class nsIFrame;
1.20 +
1.21 +// For MathML, this 'type' will be used to determine the spacing between frames
1.22 +// Subclasses can return a 'type' that will give them a particular spacing
1.23 +enum eMathMLFrameType {
1.24 + eMathMLFrameType_UNKNOWN = -1,
1.25 + eMathMLFrameType_Ordinary,
1.26 + eMathMLFrameType_OperatorOrdinary,
1.27 + eMathMLFrameType_OperatorInvisible,
1.28 + eMathMLFrameType_OperatorUserDefined,
1.29 + eMathMLFrameType_Inner,
1.30 + eMathMLFrameType_ItalicIdentifier,
1.31 + eMathMLFrameType_UprightIdentifier,
1.32 + eMathMLFrameType_COUNT
1.33 +};
1.34 +
1.35 +// Abstract base class that provides additional methods for MathML frames
1.36 +class nsIMathMLFrame
1.37 +{
1.38 +public:
1.39 + NS_DECL_QUERYFRAME_TARGET(nsIMathMLFrame)
1.40 +
1.41 + // helper to check whether the frame is "space-like", as defined by the spec.
1.42 + virtual bool IsSpaceLike() = 0;
1.43 +
1.44 + /* SUPPORT FOR PRECISE POSITIONING */
1.45 + /*====================================================================*/
1.46 +
1.47 + /* Metrics that _exactly_ enclose the text of the frame.
1.48 + * The frame *must* have *already* being reflowed, before you can call
1.49 + * the GetBoundingMetrics() method.
1.50 + * Note that for a frame with nested children, the bounding metrics
1.51 + * will exactly enclose its children. For example, the bounding metrics
1.52 + * of msub is the smallest rectangle that exactly encloses both the
1.53 + * base and the subscript.
1.54 + */
1.55 + NS_IMETHOD
1.56 + GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics) = 0;
1.57 +
1.58 + NS_IMETHOD
1.59 + SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics) = 0;
1.60 +
1.61 + NS_IMETHOD
1.62 + SetReference(const nsPoint& aReference) = 0;
1.63 +
1.64 + virtual eMathMLFrameType GetMathMLFrameType() = 0;
1.65 +
1.66 + /* SUPPORT FOR STRETCHY ELEMENTS */
1.67 + /*====================================================================*/
1.68 +
1.69 + /* Stretch :
1.70 + * Called to ask a stretchy MathML frame to stretch itself depending
1.71 + * on its context.
1.72 + *
1.73 + * An embellished frame is treated in a special way. When it receives a
1.74 + * Stretch() command, it passes the command to its embellished child and
1.75 + * the stretched size is bubbled up from the inner-most <mo> frame. In other
1.76 + * words, the stretch command descend through the embellished hierarchy.
1.77 + *
1.78 + * @param aStretchDirection [in] the direction where to attempt to
1.79 + * stretch.
1.80 + * @param aContainerSize [in] struct that suggests the maximumn size for
1.81 + * the stretched frame. Only member data of the struct that are
1.82 + * relevant to the direction are used (the rest is ignored).
1.83 + * @param aDesiredStretchSize [in/out] On input the current size
1.84 + * of the frame, on output the size after stretching.
1.85 + */
1.86 + NS_IMETHOD
1.87 + Stretch(nsRenderingContext& aRenderingContext,
1.88 + nsStretchDirection aStretchDirection,
1.89 + nsBoundingMetrics& aContainerSize,
1.90 + nsHTMLReflowMetrics& aDesiredStretchSize) = 0;
1.91 +
1.92 + /* Get the mEmbellishData member variable. */
1.93 +
1.94 + NS_IMETHOD
1.95 + GetEmbellishData(nsEmbellishData& aEmbellishData) = 0;
1.96 +
1.97 +
1.98 + /* SUPPORT FOR SCRIPTING ELEMENTS */
1.99 + /*====================================================================*/
1.100 +
1.101 + /* Get the mPresentationData member variable. */
1.102 +
1.103 + NS_IMETHOD
1.104 + GetPresentationData(nsPresentationData& aPresentationData) = 0;
1.105 +
1.106 + /* InheritAutomaticData() / TransmitAutomaticData() :
1.107 + * There are precise rules governing each MathML frame and its children.
1.108 + * Properties such as the scriptlevel or the embellished nature of a frame
1.109 + * depend on those rules. Also, certain properties that we use to emulate
1.110 + * TeX rendering rules are frame-dependent too. These two methods are meant
1.111 + * to be implemented by frame classes that need to assert specific properties
1.112 + * within their subtrees.
1.113 + *
1.114 + * InheritAutomaticData() is called in a top-down manner [like nsIFrame::Init],
1.115 + * as we descend the frame tree, whereas TransmitAutomaticData() is called in a
1.116 + * bottom-up manner, as we ascend the tree [like nsIFrame::SetInitialChildList].
1.117 + * However, unlike Init() and SetInitialChildList() which are called only once
1.118 + * during the life-time of a frame (when initially constructing the frame tree),
1.119 + * these two methods are called to build automatic data after the <math>...</math>
1.120 + * subtree has been constructed fully, and are called again as we walk a child's
1.121 + * subtree to handle dynamic changes that happen in the content model.
1.122 + *
1.123 + * As a rule of thumb:
1.124 + *
1.125 + * 1. Use InheritAutomaticData() to set properties related to your ancestors:
1.126 + * - set properties that are intrinsic to yourself
1.127 + * - set properties that depend on the state that you expect your ancestors
1.128 + * to have already reached in their own InheritAutomaticData().
1.129 + * - set properties that your descendants assume that you would have set in
1.130 + * your InheritAutomaticData() -- this way, they can safely query them and
1.131 + * the process will feed upon itself.
1.132 + *
1.133 + * 2. Use TransmitAutomaticData() to set properties related to your descendants:
1.134 + * - set properties that depend on the state that you expect your descendants
1.135 + * to have reached upon processing their own TransmitAutomaticData().
1.136 + * - transmit properties that your descendants expect that you will transmit to
1.137 + * them in your TransmitAutomaticData() -- this way, they remain up-to-date.
1.138 + * - set properties that your ancestors expect that you would set in your
1.139 + * TransmitAutomaticData() -- this way, they can safely query them and the
1.140 + * process will feed upon itself.
1.141 + */
1.142 +
1.143 + NS_IMETHOD
1.144 + InheritAutomaticData(nsIFrame* aParent) = 0;
1.145 +
1.146 + NS_IMETHOD
1.147 + TransmitAutomaticData() = 0;
1.148 +
1.149 + /* UpdatePresentationData:
1.150 + * Updates the frame's compression flag.
1.151 + * A frame becomes "compressed" (or "cramped") according to TeX rendering
1.152 + * rules (TeXBook, Ch.17, p.140-141).
1.153 + *
1.154 + * @param aFlagsValues [in]
1.155 + * The new values (e.g., compress) that are going to be
1.156 + * updated.
1.157 + *
1.158 + * @param aWhichFlags [in]
1.159 + * The flags that are relevant to this call. Since not all calls
1.160 + * are meant to update all flags at once, aWhichFlags is used
1.161 + * to distinguish flags that need to retain their existing values
1.162 + * from flags that need to be turned on (or turned off). If a bit
1.163 + * is set in aWhichFlags, then the corresponding value (which
1.164 + * can be 0 or 1) is taken from aFlagsValues and applied to the
1.165 + * frame. Therefore, by setting their bits in aWhichFlags, and
1.166 + * setting their desired values in aFlagsValues, it is possible to
1.167 + * update some flags in the frame, leaving the other flags unchanged.
1.168 + */
1.169 + NS_IMETHOD
1.170 + UpdatePresentationData(uint32_t aFlagsValues,
1.171 + uint32_t aWhichFlags) = 0;
1.172 +
1.173 + /* UpdatePresentationDataFromChildAt :
1.174 + * Sets compression flag on the whole tree. For child frames
1.175 + * at aFirstIndex up to aLastIndex, this method sets their
1.176 + * compression flags. The update is propagated down the subtrees of each of
1.177 + * these child frames.
1.178 + *
1.179 + * @param aFirstIndex [in]
1.180 + * Index of the first child from where the update is propagated.
1.181 + *
1.182 + * @param aLastIndex [in]
1.183 + * Index of the last child where to stop the update.
1.184 + * A value of -1 means up to last existing child.
1.185 + *
1.186 + * @param aFlagsValues [in]
1.187 + * The new values (e.g., compress) that are going to be
1.188 + * assigned in the whole sub-trees.
1.189 + *
1.190 + * @param aWhichFlags [in]
1.191 + * The flags that are relevant to this call. See UpdatePresentationData()
1.192 + * for more details about this parameter.
1.193 + */
1.194 + NS_IMETHOD
1.195 + UpdatePresentationDataFromChildAt(int32_t aFirstIndex,
1.196 + int32_t aLastIndex,
1.197 + uint32_t aFlagsValues,
1.198 + uint32_t aWhichFlags) = 0;
1.199 +
1.200 + // If aFrame is a child frame, returns the script increment which this frame
1.201 + // imposes on the specified frame, ignoring any artificial adjustments to
1.202 + // scriptlevel.
1.203 + // Returns 0 if the specified frame isn't a child frame.
1.204 + virtual uint8_t
1.205 + ScriptIncrement(nsIFrame* aFrame) = 0;
1.206 +
1.207 + // Returns true if the frame is considered to be an mrow for layout purposes.
1.208 + // This includes inferred mrows, but excludes <mrow> elements with a single
1.209 + // child. In the latter case, the child is to be treated as if it wasn't
1.210 + // within an mrow, so we pretend the mrow isn't mrow-like.
1.211 + virtual bool
1.212 + IsMrowLike() = 0;
1.213 +};
1.214 +
1.215 +// struct used by a container frame to keep track of its embellishments.
1.216 +// By convention, the data that we keep here is bubbled from the embellished
1.217 +// hierarchy, and it remains unchanged unless we have to recover from a change
1.218 +// that occurs in the embellished hierarchy. The struct remains in its nil
1.219 +// state in those frames that are not part of the embellished hierarchy.
1.220 +struct nsEmbellishData {
1.221 + // bits used to mark certain properties of our embellishments
1.222 + uint32_t flags;
1.223 +
1.224 + // pointer on the <mo> frame at the core of the embellished hierarchy
1.225 + nsIFrame* coreFrame;
1.226 +
1.227 + // stretchy direction that the nsMathMLChar owned by the core <mo> supports
1.228 + nsStretchDirection direction;
1.229 +
1.230 + // spacing that may come from <mo> depending on its 'form'. Since
1.231 + // the 'form' may also depend on the position of the outermost
1.232 + // embellished ancestor, the set up of these values may require
1.233 + // looking up the position of our ancestors.
1.234 + nscoord leadingSpace;
1.235 + nscoord trailingSpace;
1.236 +
1.237 + nsEmbellishData() {
1.238 + flags = 0;
1.239 + coreFrame = nullptr;
1.240 + direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
1.241 + leadingSpace = 0;
1.242 + trailingSpace = 0;
1.243 + }
1.244 +};
1.245 +
1.246 +// struct used by a container frame to modulate its presentation.
1.247 +// By convention, the data that we keep in this struct can change depending
1.248 +// on any of our ancestors and/or descendants. If a data can be resolved
1.249 +// solely from the embellished hierarchy, and it remains immutable once
1.250 +// resolved, we put it in |nsEmbellishData|. If it can be affected by other
1.251 +// things, it comes here. This struct is updated as we receive information
1.252 +// transmitted by our ancestors and is kept in sync with changes in our
1.253 +// descendants that affects us.
1.254 +struct nsPresentationData {
1.255 + // bits for: compressed, etc
1.256 + uint32_t flags;
1.257 +
1.258 + // handy pointer on our base child (the 'nucleus' in TeX), but it may be
1.259 + // null here (e.g., tags like <mrow>, <mfrac>, <mtable>, etc, won't
1.260 + // pick a particular child in their child list to be the base)
1.261 + nsIFrame* baseFrame;
1.262 +
1.263 + nsPresentationData() {
1.264 + flags = 0;
1.265 + baseFrame = nullptr;
1.266 + }
1.267 +};
1.268 +
1.269 +// ==========================================================================
1.270 +// Bits used for the presentation flags -- these bits are set
1.271 +// in their relevant situation as they become available
1.272 +
1.273 +// This bit is used to emulate TeX rendering.
1.274 +// Internal use only, cannot be set by the user with an attribute.
1.275 +#define NS_MATHML_COMPRESSED 0x00000002U
1.276 +
1.277 +// This bit is set if the frame will fire a vertical stretch
1.278 +// command on all its (non-empty) children.
1.279 +// Tags like <mrow> (or an inferred mrow), mpadded, etc, will fire a
1.280 +// vertical stretch command on all their non-empty children
1.281 +#define NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY 0x00000004U
1.282 +
1.283 +// This bit is set if the frame will fire a horizontal stretch
1.284 +// command on all its (non-empty) children.
1.285 +// Tags like munder, mover, munderover, will fire a
1.286 +// horizontal stretch command on all their non-empty children
1.287 +#define NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY 0x00000008U
1.288 +
1.289 +// This bit is set if the frame is "space-like", as defined by the spec.
1.290 +#define NS_MATHML_SPACE_LIKE 0x00000040U
1.291 +
1.292 +// This bit is set when the frame cannot be formatted due to an
1.293 +// error (e.g., invalid markup such as a <msup> without an overscript).
1.294 +// When set, a visual feedback will be provided to the user.
1.295 +#define NS_MATHML_ERROR 0x80000000U
1.296 +
1.297 +// a bit used for debug
1.298 +#define NS_MATHML_STRETCH_DONE 0x20000000U
1.299 +
1.300 +// This bit is used for visual debug. When set, the bounding box
1.301 +// of your frame is painted. This visual debug enable to ensure that
1.302 +// you have properly filled your mReference and mBoundingMetrics in
1.303 +// Place().
1.304 +#define NS_MATHML_SHOW_BOUNDING_METRICS 0x10000000U
1.305 +
1.306 +// Macros that retrieve those bits
1.307 +
1.308 +#define NS_MATHML_IS_COMPRESSED(_flags) \
1.309 + (NS_MATHML_COMPRESSED == ((_flags) & NS_MATHML_COMPRESSED))
1.310 +
1.311 +#define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(_flags) \
1.312 + (NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY == ((_flags) & NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY))
1.313 +
1.314 +#define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(_flags) \
1.315 + (NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY == ((_flags) & NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY))
1.316 +
1.317 +#define NS_MATHML_IS_SPACE_LIKE(_flags) \
1.318 + (NS_MATHML_SPACE_LIKE == ((_flags) & NS_MATHML_SPACE_LIKE))
1.319 +
1.320 +#define NS_MATHML_HAS_ERROR(_flags) \
1.321 + (NS_MATHML_ERROR == ((_flags) & NS_MATHML_ERROR))
1.322 +
1.323 +#define NS_MATHML_STRETCH_WAS_DONE(_flags) \
1.324 + (NS_MATHML_STRETCH_DONE == ((_flags) & NS_MATHML_STRETCH_DONE))
1.325 +
1.326 +#define NS_MATHML_PAINT_BOUNDING_METRICS(_flags) \
1.327 + (NS_MATHML_SHOW_BOUNDING_METRICS == ((_flags) & NS_MATHML_SHOW_BOUNDING_METRICS))
1.328 +
1.329 +// ==========================================================================
1.330 +// Bits used for the embellish flags -- these bits are set
1.331 +// in their relevant situation as they become available
1.332 +
1.333 +// This bit is set if the frame is an embellished operator.
1.334 +#define NS_MATHML_EMBELLISH_OPERATOR 0x00000001
1.335 +
1.336 +// This bit is set if the frame is an <mo> frame or an embellihsed
1.337 +// operator for which the core <mo> has movablelimits="true"
1.338 +#define NS_MATHML_EMBELLISH_MOVABLELIMITS 0x00000002
1.339 +
1.340 +// This bit is set if the frame is an <mo> frame or an embellihsed
1.341 +// operator for which the core <mo> has accent="true"
1.342 +#define NS_MATHML_EMBELLISH_ACCENT 0x00000004
1.343 +
1.344 +// This bit is set if the frame is an <mover> or <munderover> with
1.345 +// an accent frame
1.346 +#define NS_MATHML_EMBELLISH_ACCENTOVER 0x00000008
1.347 +
1.348 +// This bit is set if the frame is an <munder> or <munderover> with
1.349 +// an accentunder frame
1.350 +#define NS_MATHML_EMBELLISH_ACCENTUNDER 0x00000010
1.351 +
1.352 +// Macros that retrieve those bits
1.353 +
1.354 +#define NS_MATHML_IS_EMBELLISH_OPERATOR(_flags) \
1.355 + (NS_MATHML_EMBELLISH_OPERATOR == ((_flags) & NS_MATHML_EMBELLISH_OPERATOR))
1.356 +
1.357 +#define NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(_flags) \
1.358 + (NS_MATHML_EMBELLISH_MOVABLELIMITS == ((_flags) & NS_MATHML_EMBELLISH_MOVABLELIMITS))
1.359 +
1.360 +#define NS_MATHML_EMBELLISH_IS_ACCENT(_flags) \
1.361 + (NS_MATHML_EMBELLISH_ACCENT == ((_flags) & NS_MATHML_EMBELLISH_ACCENT))
1.362 +
1.363 +#define NS_MATHML_EMBELLISH_IS_ACCENTOVER(_flags) \
1.364 + (NS_MATHML_EMBELLISH_ACCENTOVER == ((_flags) & NS_MATHML_EMBELLISH_ACCENTOVER))
1.365 +
1.366 +#define NS_MATHML_EMBELLISH_IS_ACCENTUNDER(_flags) \
1.367 + (NS_MATHML_EMBELLISH_ACCENTUNDER == ((_flags) & NS_MATHML_EMBELLISH_ACCENTUNDER))
1.368 +
1.369 +#endif /* nsIMathMLFrame_h___ */
