OpenShot Library | libopenshot-audio 0.2.0
juce_ValueTreeSynchroniser.cpp
1/*
2 ==============================================================================
3
4 This file is part of the JUCE library.
5 Copyright (c) 2017 - ROLI Ltd.
6
7 JUCE is an open source library subject to commercial or open-source
8 licensing.
9
10 By using JUCE, you agree to the terms of both the JUCE 5 End-User License
11 Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
12 27th April 2017).
13
14 End User License Agreement: www.juce.com/juce-5-licence
15 Privacy Policy: www.juce.com/juce-5-privacy-policy
16
17 Or: You may also use this code under the terms of the GPL v3 (see
18 www.gnu.org/licenses).
19
20 JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
21 EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
22 DISCLAIMED.
23
24 ==============================================================================
25*/
26
27namespace juce
28{
29
30namespace ValueTreeSynchroniserHelpers
31{
32 enum ChangeType
33 {
34 propertyChanged = 1,
35 fullSync = 2,
36 childAdded = 3,
37 childRemoved = 4,
38 childMoved = 5,
39 propertyRemoved = 6
40 };
41
42 static void getValueTreePath (ValueTree v, const ValueTree& topLevelTree, Array<int>& path)
43 {
44 while (v != topLevelTree)
45 {
46 ValueTree parent (v.getParent());
47
48 if (! parent.isValid())
49 break;
50
51 path.add (parent.indexOf (v));
52 v = parent;
53 }
54 }
55
56 static void writeHeader (MemoryOutputStream& stream, ChangeType type)
57 {
58 stream.writeByte ((char) type);
59 }
60
61 static void writeHeader (ValueTreeSynchroniser& target, MemoryOutputStream& stream,
62 ChangeType type, ValueTree v)
63 {
64 writeHeader (stream, type);
65
66 Array<int> path;
67 getValueTreePath (v, target.getRoot(), path);
68
69 stream.writeCompressedInt (path.size());
70
71 for (int i = path.size(); --i >= 0;)
72 stream.writeCompressedInt (path.getUnchecked(i));
73 }
74
75 static ValueTree readSubTreeLocation (MemoryInputStream& input, ValueTree v)
76 {
77 const int numLevels = input.readCompressedInt();
78
79 if (! isPositiveAndBelow (numLevels, 65536)) // sanity-check
80 return {};
81
82 for (int i = numLevels; --i >= 0;)
83 {
84 const int index = input.readCompressedInt();
85
86 if (! isPositiveAndBelow (index, v.getNumChildren()))
87 return {};
88
89 v = v.getChild (index);
90 }
91
92 return v;
93 }
94}
95
97{
98 valueTree.addListener (this);
99}
100
105
107{
109 writeHeader (m, ValueTreeSynchroniserHelpers::fullSync);
110 valueTree.writeToStream (m);
111 stateChanged (m.getData(), m.getDataSize());
112}
113
114void ValueTreeSynchroniser::valueTreePropertyChanged (ValueTree& vt, const Identifier& property)
115{
117
118 if (auto* value = vt.getPropertyPointer (property))
119 {
120 ValueTreeSynchroniserHelpers::writeHeader (*this, m, ValueTreeSynchroniserHelpers::propertyChanged, vt);
121 m.writeString (property.toString());
122 value->writeToStream (m);
123 }
124 else
125 {
126 ValueTreeSynchroniserHelpers::writeHeader (*this, m, ValueTreeSynchroniserHelpers::propertyRemoved, vt);
127 m.writeString (property.toString());
128 }
129
131}
132
133void ValueTreeSynchroniser::valueTreeChildAdded (ValueTree& parentTree, ValueTree& childTree)
134{
135 const int index = parentTree.indexOf (childTree);
136 jassert (index >= 0);
137
138 MemoryOutputStream m;
139 ValueTreeSynchroniserHelpers::writeHeader (*this, m, ValueTreeSynchroniserHelpers::childAdded, parentTree);
140 m.writeCompressedInt (index);
141 childTree.writeToStream (m);
142 stateChanged (m.getData(), m.getDataSize());
143}
144
145void ValueTreeSynchroniser::valueTreeChildRemoved (ValueTree& parentTree, ValueTree&, int oldIndex)
146{
147 MemoryOutputStream m;
148 ValueTreeSynchroniserHelpers::writeHeader (*this, m, ValueTreeSynchroniserHelpers::childRemoved, parentTree);
149 m.writeCompressedInt (oldIndex);
150 stateChanged (m.getData(), m.getDataSize());
151}
152
153void ValueTreeSynchroniser::valueTreeChildOrderChanged (ValueTree& parent, int oldIndex, int newIndex)
154{
155 MemoryOutputStream m;
156 ValueTreeSynchroniserHelpers::writeHeader (*this, m, ValueTreeSynchroniserHelpers::childMoved, parent);
157 m.writeCompressedInt (oldIndex);
158 m.writeCompressedInt (newIndex);
159 stateChanged (m.getData(), m.getDataSize());
160}
161
162void ValueTreeSynchroniser::valueTreeParentChanged (ValueTree&) {} // (No action needed here)
163
164bool ValueTreeSynchroniser::applyChange (ValueTree& root, const void* data, size_t dataSize, UndoManager* undoManager)
165{
166 MemoryInputStream input (data, dataSize, false);
167
168 const ValueTreeSynchroniserHelpers::ChangeType type = (ValueTreeSynchroniserHelpers::ChangeType) input.readByte();
169
170 if (type == ValueTreeSynchroniserHelpers::fullSync)
171 {
172 root = ValueTree::readFromStream (input);
173 return true;
174 }
175
176 ValueTree v (ValueTreeSynchroniserHelpers::readSubTreeLocation (input, root));
177
178 if (! v.isValid())
179 return false;
180
181 switch (type)
182 {
183 case ValueTreeSynchroniserHelpers::propertyChanged:
184 {
185 Identifier property (input.readString());
186 v.setProperty (property, var::readFromStream (input), undoManager);
187 return true;
188 }
189
190 case ValueTreeSynchroniserHelpers::propertyRemoved:
191 {
192 Identifier property (input.readString());
193 v.removeProperty (property, undoManager);
194 return true;
195 }
196
197 case ValueTreeSynchroniserHelpers::childAdded:
198 {
199 const int index = input.readCompressedInt();
200 v.addChild (ValueTree::readFromStream (input), index, undoManager);
201 return true;
202 }
203
204 case ValueTreeSynchroniserHelpers::childRemoved:
205 {
206 const int index = input.readCompressedInt();
207
208 if (isPositiveAndBelow (index, v.getNumChildren()))
209 {
210 v.removeChild (index, undoManager);
211 return true;
212 }
213
214 jassertfalse; // Either received some corrupt data, or the trees have drifted out of sync
215 break;
216 }
217
218 case ValueTreeSynchroniserHelpers::childMoved:
219 {
220 const int oldIndex = input.readCompressedInt();
221 const int newIndex = input.readCompressedInt();
222
223 if (isPositiveAndBelow (oldIndex, v.getNumChildren())
224 && isPositiveAndBelow (newIndex, v.getNumChildren()))
225 {
226 v.moveChild (oldIndex, newIndex, undoManager);
227 return true;
228 }
229
230 jassertfalse; // Either received some corrupt data, or the trees have drifted out of sync
231 break;
232 }
233
234 default:
235 jassertfalse; // Seem to have received some corrupt data?
236 break;
237 }
238
239 return false;
240}
241
242} // namespace juce
Holds a resizable array of primitive or copy-by-value objects.
Definition juce_Array.h:60
Represents a string identifier, designed for accessing properties by name.
const String & toString() const noexcept
Returns this identifier as a string.
virtual int readCompressedInt()
Reads an encoded 32-bit number from the stream using a space-saving compressed format.
virtual String readString()
Reads a zero-terminated UTF-8 string from the stream.
virtual char readByte()
Reads a byte from the stream.
Allows a block of data to be accessed as a stream.
Writes data to an internal memory buffer, which grows as required.
const void * getData() const noexcept
Returns a pointer to the data that has been written to the stream.
size_t getDataSize() const noexcept
Returns the number of bytes of data that have been written to the stream.
virtual bool writeString(const String &text)
Stores a string in the stream in a binary format.
Manages a list of undo/redo commands.
static bool applyChange(ValueTree &target, const void *encodedChangeData, size_t encodedChangeDataSize, UndoManager *undoManager)
Applies an encoded change to the given destination tree.
virtual void stateChanged(const void *encodedChange, size_t encodedChangeSize)=0
This callback happens when the ValueTree changes and the given state-change message needs to be appli...
ValueTreeSynchroniser(const ValueTree &tree)
Creates a ValueTreeSynchroniser that watches the given tree.
void sendFullSyncCallback()
Forces the sending of a full state message, which may be large, as it encodes the entire ValueTree.
A powerful tree structure that can be used to hold free-form data, and which can handle its own undo ...
static ValueTree readFromStream(InputStream &input)
Reloads a tree from a stream that was written with writeToStream().
void addListener(Listener *listener)
Adds a listener to receive callbacks when this tree is changed in some way.
void removeListener(Listener *listener)
Removes a listener that was previously added with addListener().
void writeToStream(OutputStream &output) const
Stores this tree (and all its children) in a binary format.
static var readFromStream(InputStream &input)
Reads back a stored binary representation of a value.