The Tor Browser / file comparison

comparison: layout/mathml/nsIMathMLFrame.h

layout/mathml/nsIMathMLFrame.h

branch
TOR_BUG_9701
changeset 14
925c144e1f1f
equal deleted inserted replaced
-1:000000000000 0:f7b551725537
1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5 //#define SHOW_BOUNDING_BOX 1
6 #ifndef nsIMathMLFrame_h___
7 #define nsIMathMLFrame_h___
8
9 #include "nsQueryFrame.h"
10 #include "nsMathMLOperators.h"
11
12 struct nsPresentationData;
13 struct nsEmbellishData;
14 struct nsHTMLReflowMetrics;
15 class nsRenderingContext;
16 class nsIFrame;
17
18 // For MathML, this 'type' will be used to determine the spacing between frames
19 // Subclasses can return a 'type' that will give them a particular spacing
20 enum eMathMLFrameType {
21 eMathMLFrameType_UNKNOWN = -1,
22 eMathMLFrameType_Ordinary,
23 eMathMLFrameType_OperatorOrdinary,
24 eMathMLFrameType_OperatorInvisible,
25 eMathMLFrameType_OperatorUserDefined,
26 eMathMLFrameType_Inner,
27 eMathMLFrameType_ItalicIdentifier,
28 eMathMLFrameType_UprightIdentifier,
29 eMathMLFrameType_COUNT
30 };
31
32 // Abstract base class that provides additional methods for MathML frames
33 class nsIMathMLFrame
34 {
35 public:
36 NS_DECL_QUERYFRAME_TARGET(nsIMathMLFrame)
37
38 // helper to check whether the frame is "space-like", as defined by the spec.
39 virtual bool IsSpaceLike() = 0;
40
41 /* SUPPORT FOR PRECISE POSITIONING */
42 /*====================================================================*/
43
44 /* Metrics that _exactly_ enclose the text of the frame.
45 * The frame *must* have *already* being reflowed, before you can call
46 * the GetBoundingMetrics() method.
47 * Note that for a frame with nested children, the bounding metrics
48 * will exactly enclose its children. For example, the bounding metrics
49 * of msub is the smallest rectangle that exactly encloses both the
50 * base and the subscript.
51 */
52 NS_IMETHOD
53 GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics) = 0;
54
55 NS_IMETHOD
56 SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics) = 0;
57
58 NS_IMETHOD
59 SetReference(const nsPoint& aReference) = 0;
60
61 virtual eMathMLFrameType GetMathMLFrameType() = 0;
62
63 /* SUPPORT FOR STRETCHY ELEMENTS */
64 /*====================================================================*/
65
66 /* Stretch :
67 * Called to ask a stretchy MathML frame to stretch itself depending
68 * on its context.
69 *
70 * An embellished frame is treated in a special way. When it receives a
71 * Stretch() command, it passes the command to its embellished child and
72 * the stretched size is bubbled up from the inner-most <mo> frame. In other
73 * words, the stretch command descend through the embellished hierarchy.
74 *
75 * @param aStretchDirection [in] the direction where to attempt to
76 * stretch.
77 * @param aContainerSize [in] struct that suggests the maximumn size for
78 * the stretched frame. Only member data of the struct that are
79 * relevant to the direction are used (the rest is ignored).
80 * @param aDesiredStretchSize [in/out] On input the current size
81 * of the frame, on output the size after stretching.
82 */
83 NS_IMETHOD
84 Stretch(nsRenderingContext& aRenderingContext,
85 nsStretchDirection aStretchDirection,
86 nsBoundingMetrics& aContainerSize,
87 nsHTMLReflowMetrics& aDesiredStretchSize) = 0;
88
89 /* Get the mEmbellishData member variable. */
90
91 NS_IMETHOD
92 GetEmbellishData(nsEmbellishData& aEmbellishData) = 0;
93
94
95 /* SUPPORT FOR SCRIPTING ELEMENTS */
96 /*====================================================================*/
97
98 /* Get the mPresentationData member variable. */
99
100 NS_IMETHOD
101 GetPresentationData(nsPresentationData& aPresentationData) = 0;
102
103 /* InheritAutomaticData() / TransmitAutomaticData() :
104 * There are precise rules governing each MathML frame and its children.
105 * Properties such as the scriptlevel or the embellished nature of a frame
106 * depend on those rules. Also, certain properties that we use to emulate
107 * TeX rendering rules are frame-dependent too. These two methods are meant
108 * to be implemented by frame classes that need to assert specific properties
109 * within their subtrees.
110 *
111 * InheritAutomaticData() is called in a top-down manner [like nsIFrame::Init],
112 * as we descend the frame tree, whereas TransmitAutomaticData() is called in a
113 * bottom-up manner, as we ascend the tree [like nsIFrame::SetInitialChildList].
114 * However, unlike Init() and SetInitialChildList() which are called only once
115 * during the life-time of a frame (when initially constructing the frame tree),
116 * these two methods are called to build automatic data after the <math>...</math>
117 * subtree has been constructed fully, and are called again as we walk a child's
118 * subtree to handle dynamic changes that happen in the content model.
119 *
120 * As a rule of thumb:
121 *
122 * 1. Use InheritAutomaticData() to set properties related to your ancestors:
123 * - set properties that are intrinsic to yourself
124 * - set properties that depend on the state that you expect your ancestors
125 * to have already reached in their own InheritAutomaticData().
126 * - set properties that your descendants assume that you would have set in
127 * your InheritAutomaticData() -- this way, they can safely query them and
128 * the process will feed upon itself.
129 *
130 * 2. Use TransmitAutomaticData() to set properties related to your descendants:
131 * - set properties that depend on the state that you expect your descendants
132 * to have reached upon processing their own TransmitAutomaticData().
133 * - transmit properties that your descendants expect that you will transmit to
134 * them in your TransmitAutomaticData() -- this way, they remain up-to-date.
135 * - set properties that your ancestors expect that you would set in your
136 * TransmitAutomaticData() -- this way, they can safely query them and the
137 * process will feed upon itself.
138 */
139
140 NS_IMETHOD
141 InheritAutomaticData(nsIFrame* aParent) = 0;
142
143 NS_IMETHOD
144 TransmitAutomaticData() = 0;
145
146 /* UpdatePresentationData:
147 * Updates the frame's compression flag.
148 * A frame becomes "compressed" (or "cramped") according to TeX rendering
149 * rules (TeXBook, Ch.17, p.140-141).
150 *
151 * @param aFlagsValues [in]
152 * The new values (e.g., compress) that are going to be
153 * updated.
154 *
155 * @param aWhichFlags [in]
156 * The flags that are relevant to this call. Since not all calls
157 * are meant to update all flags at once, aWhichFlags is used
158 * to distinguish flags that need to retain their existing values
159 * from flags that need to be turned on (or turned off). If a bit
160 * is set in aWhichFlags, then the corresponding value (which
161 * can be 0 or 1) is taken from aFlagsValues and applied to the
162 * frame. Therefore, by setting their bits in aWhichFlags, and
163 * setting their desired values in aFlagsValues, it is possible to
164 * update some flags in the frame, leaving the other flags unchanged.
165 */
166 NS_IMETHOD
167 UpdatePresentationData(uint32_t aFlagsValues,
168 uint32_t aWhichFlags) = 0;
169
170 /* UpdatePresentationDataFromChildAt :
171 * Sets compression flag on the whole tree. For child frames
172 * at aFirstIndex up to aLastIndex, this method sets their
173 * compression flags. The update is propagated down the subtrees of each of
174 * these child frames.
175 *
176 * @param aFirstIndex [in]
177 * Index of the first child from where the update is propagated.
178 *
179 * @param aLastIndex [in]
180 * Index of the last child where to stop the update.
181 * A value of -1 means up to last existing child.
182 *
183 * @param aFlagsValues [in]
184 * The new values (e.g., compress) that are going to be
185 * assigned in the whole sub-trees.
186 *
187 * @param aWhichFlags [in]
188 * The flags that are relevant to this call. See UpdatePresentationData()
189 * for more details about this parameter.
190 */
191 NS_IMETHOD
192 UpdatePresentationDataFromChildAt(int32_t aFirstIndex,
193 int32_t aLastIndex,
194 uint32_t aFlagsValues,
195 uint32_t aWhichFlags) = 0;
196
197 // If aFrame is a child frame, returns the script increment which this frame
198 // imposes on the specified frame, ignoring any artificial adjustments to
199 // scriptlevel.
200 // Returns 0 if the specified frame isn't a child frame.
201 virtual uint8_t
202 ScriptIncrement(nsIFrame* aFrame) = 0;
203
204 // Returns true if the frame is considered to be an mrow for layout purposes.
205 // This includes inferred mrows, but excludes <mrow> elements with a single
206 // child. In the latter case, the child is to be treated as if it wasn't
207 // within an mrow, so we pretend the mrow isn't mrow-like.
208 virtual bool
209 IsMrowLike() = 0;
210 };
211
212 // struct used by a container frame to keep track of its embellishments.
213 // By convention, the data that we keep here is bubbled from the embellished
214 // hierarchy, and it remains unchanged unless we have to recover from a change
215 // that occurs in the embellished hierarchy. The struct remains in its nil
216 // state in those frames that are not part of the embellished hierarchy.
217 struct nsEmbellishData {
218 // bits used to mark certain properties of our embellishments
219 uint32_t flags;
220
221 // pointer on the <mo> frame at the core of the embellished hierarchy
222 nsIFrame* coreFrame;
223
224 // stretchy direction that the nsMathMLChar owned by the core <mo> supports
225 nsStretchDirection direction;
226
227 // spacing that may come from <mo> depending on its 'form'. Since
228 // the 'form' may also depend on the position of the outermost
229 // embellished ancestor, the set up of these values may require
230 // looking up the position of our ancestors.
231 nscoord leadingSpace;
232 nscoord trailingSpace;
233
234 nsEmbellishData() {
235 flags = 0;
236 coreFrame = nullptr;
237 direction = NS_STRETCH_DIRECTION_UNSUPPORTED;
238 leadingSpace = 0;
239 trailingSpace = 0;
240 }
241 };
242
243 // struct used by a container frame to modulate its presentation.
244 // By convention, the data that we keep in this struct can change depending
245 // on any of our ancestors and/or descendants. If a data can be resolved
246 // solely from the embellished hierarchy, and it remains immutable once
247 // resolved, we put it in |nsEmbellishData|. If it can be affected by other
248 // things, it comes here. This struct is updated as we receive information
249 // transmitted by our ancestors and is kept in sync with changes in our
250 // descendants that affects us.
251 struct nsPresentationData {
252 // bits for: compressed, etc
253 uint32_t flags;
254
255 // handy pointer on our base child (the 'nucleus' in TeX), but it may be
256 // null here (e.g., tags like <mrow>, <mfrac>, <mtable>, etc, won't
257 // pick a particular child in their child list to be the base)
258 nsIFrame* baseFrame;
259
260 nsPresentationData() {
261 flags = 0;
262 baseFrame = nullptr;
263 }
264 };
265
266 // ==========================================================================
267 // Bits used for the presentation flags -- these bits are set
268 // in their relevant situation as they become available
269
270 // This bit is used to emulate TeX rendering.
271 // Internal use only, cannot be set by the user with an attribute.
272 #define NS_MATHML_COMPRESSED 0x00000002U
273
274 // This bit is set if the frame will fire a vertical stretch
275 // command on all its (non-empty) children.
276 // Tags like <mrow> (or an inferred mrow), mpadded, etc, will fire a
277 // vertical stretch command on all their non-empty children
278 #define NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY 0x00000004U
279
280 // This bit is set if the frame will fire a horizontal stretch
281 // command on all its (non-empty) children.
282 // Tags like munder, mover, munderover, will fire a
283 // horizontal stretch command on all their non-empty children
284 #define NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY 0x00000008U
285
286 // This bit is set if the frame is "space-like", as defined by the spec.
287 #define NS_MATHML_SPACE_LIKE 0x00000040U
288
289 // This bit is set when the frame cannot be formatted due to an
290 // error (e.g., invalid markup such as a <msup> without an overscript).
291 // When set, a visual feedback will be provided to the user.
292 #define NS_MATHML_ERROR 0x80000000U
293
294 // a bit used for debug
295 #define NS_MATHML_STRETCH_DONE 0x20000000U
296
297 // This bit is used for visual debug. When set, the bounding box
298 // of your frame is painted. This visual debug enable to ensure that
299 // you have properly filled your mReference and mBoundingMetrics in
300 // Place().
301 #define NS_MATHML_SHOW_BOUNDING_METRICS 0x10000000U
302
303 // Macros that retrieve those bits
304
305 #define NS_MATHML_IS_COMPRESSED(_flags) \
306 (NS_MATHML_COMPRESSED == ((_flags) & NS_MATHML_COMPRESSED))
307
308 #define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(_flags) \
309 (NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY == ((_flags) & NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY))
310
311 #define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(_flags) \
312 (NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY == ((_flags) & NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY))
313
314 #define NS_MATHML_IS_SPACE_LIKE(_flags) \
315 (NS_MATHML_SPACE_LIKE == ((_flags) & NS_MATHML_SPACE_LIKE))
316
317 #define NS_MATHML_HAS_ERROR(_flags) \
318 (NS_MATHML_ERROR == ((_flags) & NS_MATHML_ERROR))
319
320 #define NS_MATHML_STRETCH_WAS_DONE(_flags) \
321 (NS_MATHML_STRETCH_DONE == ((_flags) & NS_MATHML_STRETCH_DONE))
322
323 #define NS_MATHML_PAINT_BOUNDING_METRICS(_flags) \
324 (NS_MATHML_SHOW_BOUNDING_METRICS == ((_flags) & NS_MATHML_SHOW_BOUNDING_METRICS))
325
326 // ==========================================================================
327 // Bits used for the embellish flags -- these bits are set
328 // in their relevant situation as they become available
329
330 // This bit is set if the frame is an embellished operator.
331 #define NS_MATHML_EMBELLISH_OPERATOR 0x00000001
332
333 // This bit is set if the frame is an <mo> frame or an embellihsed
334 // operator for which the core <mo> has movablelimits="true"
335 #define NS_MATHML_EMBELLISH_MOVABLELIMITS 0x00000002
336
337 // This bit is set if the frame is an <mo> frame or an embellihsed
338 // operator for which the core <mo> has accent="true"
339 #define NS_MATHML_EMBELLISH_ACCENT 0x00000004
340
341 // This bit is set if the frame is an <mover> or <munderover> with
342 // an accent frame
343 #define NS_MATHML_EMBELLISH_ACCENTOVER 0x00000008
344
345 // This bit is set if the frame is an <munder> or <munderover> with
346 // an accentunder frame
347 #define NS_MATHML_EMBELLISH_ACCENTUNDER 0x00000010
348
349 // Macros that retrieve those bits
350
351 #define NS_MATHML_IS_EMBELLISH_OPERATOR(_flags) \
352 (NS_MATHML_EMBELLISH_OPERATOR == ((_flags) & NS_MATHML_EMBELLISH_OPERATOR))
353
354 #define NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(_flags) \
355 (NS_MATHML_EMBELLISH_MOVABLELIMITS == ((_flags) & NS_MATHML_EMBELLISH_MOVABLELIMITS))
356
357 #define NS_MATHML_EMBELLISH_IS_ACCENT(_flags) \
358 (NS_MATHML_EMBELLISH_ACCENT == ((_flags) & NS_MATHML_EMBELLISH_ACCENT))
359
360 #define NS_MATHML_EMBELLISH_IS_ACCENTOVER(_flags) \
361 (NS_MATHML_EMBELLISH_ACCENTOVER == ((_flags) & NS_MATHML_EMBELLISH_ACCENTOVER))
362
363 #define NS_MATHML_EMBELLISH_IS_ACCENTUNDER(_flags) \
364 (NS_MATHML_EMBELLISH_ACCENTUNDER == ((_flags) & NS_MATHML_EMBELLISH_ACCENTUNDER))
365
366 #endif /* nsIMathMLFrame_h___ */

Mercurial Repository: The Tor Browser

Europalab SCM Repository Server

mercurial