-
-
Notifications
You must be signed in to change notification settings - Fork 164
/
BaseCommand.cs
158 lines (139 loc) · 5.06 KB
/
BaseCommand.cs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
// Copyright 2020 The Tilt Brush Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
using System;
using System.Linq;
using System.Collections.Generic;
using UnityEngine;
namespace TiltBrush
{
/// Commands on the undo stack of SketchMemoryScript
///
/// Subclasses should override the virtual methods to
/// implement their custom behavior, and must either call
/// the base class or be sure to recurse into children.
public class BaseCommand : IDisposable
{
private Guid m_Guid;
private BaseCommand m_Parent;
protected List<BaseCommand> m_Children;
public int ChildrenCount
{
get { return m_Children.Count; }
}
public Guid Guid
{
get { return m_Guid; }
}
public List<BaseCommand> Children
{
get { return m_Children.ToList(); }
}
public Guid ParentGuid
{
get { return m_Parent != null ? m_Parent.Guid : Guid.Empty; }
}
protected static Vector3 GetPositionForCommand(Stroke stroke)
{
var points = stroke.m_ControlPoints;
Debug.Assert(points != null && points.Length > 0);
return (points[0].m_Pos + points[points.Length - 1].m_Pos) * .5f;
}
protected static Vector3 GetPositionForCommand(Stroke[] strokes)
{
Debug.Assert(strokes != null);
if (strokes.Length == 0) { return Vector3.zero; }
return GetPositionForCommand(strokes[0]);
}
/// Create this command as a child of the passed command.
/// Commands with parents should not be placed on the undo
/// stack; only the root parent should be.
/// The constructor should not mutate sketch state.
public BaseCommand(BaseCommand parent = null)
{
m_Guid = Guid.NewGuid();
m_Children = new List<BaseCommand>();
if (parent != null)
{
parent.m_Children.Add(this);
m_Parent = parent;
}
}
/// True if this command changes the sketch in a saveable
/// manner. This command matters if any of its children do.
virtual public bool NeedsSave
{
get
{
return m_Children.Count > 0 && m_Children.Any(c => c.NeedsSave);
}
}
/// True if this command does not change any state. This should occur
/// only due to merging of commands. This getter is properly overridden
/// only for SwitchEnvironmentCommand and PropVisibleCommand as they are
/// the only commands whose merge functions can put them in no-op states.
virtual protected bool IsNoop { get { return false; } }
/// Undo this entire command tree.
/// Parent is always undone after all children.
/// Children are undone in reverse order.
public void Undo()
{
foreach (BaseCommand comm in m_Children.AsEnumerable().Reverse())
{
comm.Undo();
}
OnUndo();
}
virtual protected void OnUndo() { }
/// Redo this entire command tree.
/// Parent is always redone before all children.
/// Children are redone in order.
public void Redo()
{
OnRedo();
foreach (BaseCommand comm in m_Children)
{
comm.Redo();
}
}
virtual protected void OnRedo() { }
/// API is only for undo/redo stack.
/// Override to define how a command can merge with another.
/// Returns true upon successful merge, otherwise false.
/// This command is redone before other and undone after other.
///
/// The base implementation discards no-op commands and should
/// and should always be called by subclasses.
public virtual bool Merge(BaseCommand other)
{
return other.IsNoop;
}
public virtual string Serialize()
{
return string.Empty;
}
/// Dispose of this entire command tree if there are any
/// controlled resources.
/// Parent is always destroyed after all children.
/// Children are destroyed in reverse order.
public void Dispose()
{
foreach (BaseCommand comm in m_Children.AsEnumerable().Reverse())
{
comm.Dispose();
}
OnDispose();
}
virtual protected void OnDispose() { }
}
} // namespace TiltBrush