blob: 4ec530d3bad75a9ce08899a1abcb6800c222e9e7 (
plain)
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
|
//=============================================================================
// Copyright 2006-2010 Daniel W. Dyer
//
// 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.
//=============================================================================
package org.uncommons.watchmaker.examples.monalisa;
import java.awt.Dimension;
import java.awt.Point;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import org.uncommons.maths.number.ConstantGenerator;
import org.uncommons.maths.number.NumberGenerator;
import org.uncommons.maths.random.Probability;
/**
* Evolutionary operator for mutating individual polygons. Polygons are mutated
* by removing a point, according to some probability.
* @author Daniel Dyer
*/
public class RemoveVertexMutation extends AbstractVertexMutation
{
/**
* @param mutationProbability A {@link NumberGenerator} that controls the
* probability that a point will be removed.
* @param canvasSize The size of the canvas. Used to constrain the positions
* of the points.
*/
public RemoveVertexMutation(Dimension canvasSize,
NumberGenerator<Probability> mutationProbability)
{
super(mutationProbability, canvasSize);
}
/**
* @param mutationProbability The probability that a point will be removed.
* @param canvasSize The size of the canvas. Used to constrain the positions
* of the points.
*/
public RemoveVertexMutation(Dimension canvasSize,
Probability mutationProbability)
{
this(canvasSize, new ConstantGenerator<Probability>(mutationProbability));
}
@Override
protected List<Point> mutateVertices(List<Point> vertices, Random rng)
{
// A single point is removed with the configured probability, unless
// we already have the minimum permitted number of points.
if (vertices.size() > PolygonImageFactory.MINIMUM_VERTEX_COUNT
&& getMutationProbability().nextValue().nextEvent(rng))
{
List<Point> newVertices = new ArrayList<Point>(vertices);
newVertices.remove(rng.nextInt(newVertices.size()));
return newVertices;
}
else // Nothing changed.
{
return vertices;
}
}
}
|
