1 : /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 : /* ***** BEGIN LICENSE BLOCK *****
3 : * Version: MPL 1.1/GPL 2.0/LGPL 2.1
4 : *
5 : * The contents of this file are subject to the Mozilla Public License Version
6 : * 1.1 (the "License"); you may not use this file except in compliance with
7 : * the License. You may obtain a copy of the License at
8 : * http://www.mozilla.org/MPL/
9 : *
10 : * Software distributed under the License is distributed on an "AS IS" basis,
11 : * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
12 : * for the specific language governing rights and limitations under the
13 : * License.
14 : *
15 : * The Original Code is the Mozilla SMIL module.
16 : *
17 : * The Initial Developer of the Original Code is Brian Birtles.
18 : * Portions created by the Initial Developer are Copyright (C) 2005
19 : * the Initial Developer. All Rights Reserved.
20 : *
21 : * Contributor(s):
22 : * Brian Birtles <birtles@gmail.com>
23 : *
24 : * Alternatively, the contents of this file may be used under the terms of
25 : * either of the GNU General Public License Version 2 or later (the "GPL"),
26 : * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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33 : * the provisions above, a recipient may use your version of this file under
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35 : *
36 : * ***** END LICENSE BLOCK ***** */
37 :
38 : #ifndef NS_SMILINSTANCETIME_H_
39 : #define NS_SMILINSTANCETIME_H_
40 :
41 : #include "nsSMILTimeValue.h"
42 : #include "nsAutoPtr.h"
43 :
44 : class nsSMILInterval;
45 : class nsSMILTimeContainer;
46 : class nsSMILTimeValueSpec;
47 :
48 : //----------------------------------------------------------------------
49 : // nsSMILInstanceTime
50 : //
51 : // An instant in document simple time that may be used in creating a new
52 : // interval.
53 : //
54 : // For an overview of how this class is related to other SMIL time classes see
55 : // the documentation in nsSMILTimeValue.h
56 : //
57 : // These objects are owned by an nsSMILTimedElement but MAY also be referenced
58 : // by:
59 : //
60 : // a) nsSMILIntervals that belong to the same nsSMILTimedElement and which refer
61 : // to the nsSMILInstanceTimes which form the interval endpoints; and/or
62 : // b) nsSMILIntervals that belong to other nsSMILTimedElements but which need to
63 : // update dependent instance times when they change or are deleted.
64 : // E.g. for begin='a.begin', 'a' needs to inform dependent
65 : // nsSMILInstanceTimes if its begin time changes. This notification is
66 : // performed by the nsSMILInterval.
67 :
68 : class nsSMILInstanceTime
69 : {
70 : public:
71 : // Instance time source. Times generated by events, syncbase relationships,
72 : // and DOM calls behave differently in some circumstances such as when a timed
73 : // element is reset.
74 : enum nsSMILInstanceTimeSource {
75 : // No particularly significant source, e.g. offset time, 'indefinite'
76 : SOURCE_NONE,
77 : // Generated by a DOM call such as beginElement
78 : SOURCE_DOM,
79 : // Generated by a syncbase relationship
80 : SOURCE_SYNCBASE,
81 : // Generated by an event
82 : SOURCE_EVENT
83 : };
84 :
85 : nsSMILInstanceTime(const nsSMILTimeValue& aTime,
86 : nsSMILInstanceTimeSource aSource = SOURCE_NONE,
87 : nsSMILTimeValueSpec* aCreator = nsnull,
88 : nsSMILInterval* aBaseInterval = nsnull);
89 : ~nsSMILInstanceTime();
90 : void Unlink();
91 : void HandleChangedInterval(const nsSMILTimeContainer* aSrcContainer,
92 : bool aBeginObjectChanged,
93 : bool aEndObjectChanged);
94 : void HandleDeletedInterval();
95 : void HandleFilteredInterval();
96 :
97 0 : const nsSMILTimeValue& Time() const { return mTime; }
98 0 : const nsSMILTimeValueSpec* GetCreator() const { return mCreator; }
99 :
100 0 : bool IsDynamic() const { return !!(mFlags & kDynamic); }
101 0 : bool IsFixedTime() const { return !(mFlags & kMayUpdate); }
102 0 : bool FromDOM() const { return !!(mFlags & kFromDOM); }
103 :
104 : bool ShouldPreserve() const;
105 : void UnmarkShouldPreserve();
106 :
107 : void AddRefFixedEndpoint();
108 : void ReleaseFixedEndpoint();
109 :
110 0 : void DependentUpdate(const nsSMILTimeValue& aNewTime)
111 : {
112 0 : NS_ABORT_IF_FALSE(!IsFixedTime(),
113 : "Updating an instance time that is not expected to be updated");
114 0 : mTime = aNewTime;
115 0 : }
116 :
117 0 : bool IsDependent() const { return !!mBaseInterval; }
118 : bool IsDependentOn(const nsSMILInstanceTime& aOther) const;
119 0 : const nsSMILInterval* GetBaseInterval() const { return mBaseInterval; }
120 : const nsSMILInstanceTime* GetBaseTime() const;
121 :
122 0 : bool SameTimeAndBase(const nsSMILInstanceTime& aOther) const
123 : {
124 0 : return mTime == aOther.mTime && GetBaseTime() == aOther.GetBaseTime();
125 : }
126 :
127 : // Get and set a serial number which may be used by a containing class to
128 : // control the sort order of otherwise similar instance times.
129 0 : PRUint32 Serial() const { return mSerial; }
130 0 : void SetSerial(PRUint32 aIndex) { mSerial = aIndex; }
131 :
132 0 : NS_INLINE_DECL_REFCOUNTING(nsSMILInstanceTime)
133 :
134 : protected:
135 : void SetBaseInterval(nsSMILInterval* aBaseInterval);
136 :
137 : nsSMILTimeValue mTime;
138 :
139 : // Internal flags used to represent the behaviour of different instance times
140 : enum {
141 : // Indicates that this instance time was generated by an event or a DOM
142 : // call. Such instance times require special handling when (i) the owning
143 : // element is reset, (ii) when they are to be added as a new end instance
144 : // times (as per SMIL's event sensitivity contraints), and (iii) when
145 : // a backwards seek is performed and the timing model is reconstructed.
146 : kDynamic = 1,
147 :
148 : // Indicates that this instance time is referred to by an
149 : // nsSMILTimeValueSpec and as such may be updated. Such instance time should
150 : // not be filtered out by the nsSMILTimedElement even if they appear to be
151 : // in the past as they may be updated to a future time.
152 : kMayUpdate = 2,
153 :
154 : // Indicates that this instance time was generated from the DOM as opposed
155 : // to an nsSMILTimeValueSpec. When a 'begin' or 'end' attribute is set or
156 : // reset we should clear all the instance times that have been generated by
157 : // that attribute (and hence an nsSMILTimeValueSpec), but not those from the
158 : // DOM.
159 : kFromDOM = 4,
160 :
161 : // Indicates that this instance time was used as the endpoint of an interval
162 : // that has been filtered or removed. However, since it is a dynamic time it
163 : // should be preserved and not filtered.
164 : kWasDynamicEndpoint = 8
165 : };
166 : PRUint8 mFlags; // Combination of kDynamic, kMayUpdate, etc.
167 : bool mVisited; // (mutable) Cycle tracking
168 :
169 : // Additional reference count to determine if this instance time is currently
170 : // used as a fixed endpoint in any intervals. Instance times that are used in
171 : // this way should not be removed when the owning nsSMILTimedElement removes
172 : // instance times in response to a restart or in an attempt to free up memory
173 : // by filtering out old instance times.
174 : //
175 : // Instance times are only shared in a few cases, namely:
176 : // a) early ends,
177 : // b) zero-duration intervals,
178 : // c) momentarily whilst establishing new intervals and updating the current
179 : // interval, and
180 : // d) trimmed intervals
181 : // Hence the limited range of a PRUint16 should be more than adequate.
182 : PRUint16 mFixedEndpointRefCnt;
183 :
184 : PRUint32 mSerial; // A serial number used by the containing class to
185 : // specify the sort order for instance times with the
186 : // same mTime.
187 :
188 : nsSMILTimeValueSpec* mCreator; // The nsSMILTimeValueSpec object that created
189 : // us. (currently only needed for syncbase
190 : // instance times.)
191 : nsSMILInterval* mBaseInterval; // Interval from which this time is derived
192 : // (only used for syncbase instance times)
193 : };
194 :
195 : #endif // NS_SMILINSTANCETIME_H_
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