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私はこの実装を取得しようとしています軸の分離をに分けることはできますが、ポリゴン同士が近接していると衝突が検出されることがあります。どうしたの？コードが...最適化が次のステップであるという事実を別にすれば、ここでは問題はありません。しかし、読むのは簡単なはずです。SAT Javaの実装
import javax.swing.JPanel;
import javax.swing.JFrame;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.util.ArrayList;
public class SAT
{
public static boolean SAT(Polygon p1, Polygon p2)
{
ArrayList<Vector> normals = new ArrayList<Vector>();
//recover normal vectors for p1 and p2
for (int i = 0; i < p1.getPointCount(); i++)
{
if (i < p1.getPointCount() - 1)
{
float x = p1.getPoint(i + 1).x + p1.getPosition().x - p1.getPoint(i).x + p1.getPosition().x;
float y = p1.getPoint(i + 1).y + p1.getPosition().y - p1.getPoint(i).y + p1.getPosition().y;
normals.add(new Vector(x, y).getNormalVectorLeft());
}
else
{
float x = p1.getPoint(0).x + p1.getPosition().x - p1.getPoint(i).x + p1.getPosition().x;
float y = p1.getPoint(0).y + p1.getPosition().y - p1.getPoint(i).y + p1.getPosition().y;
normals.add(new Vector(x, y).getNormalVectorLeft());
}
}
for (int i = 0; i < p2.getPointCount(); i++)
{
if (i < p2.getPointCount() - 1)
{
float x = p2.getPoint(i + 1).x + p2.getPosition().x - p2.getPoint(i).x + p2.getPosition().x;
float y = p2.getPoint(i + 1).y + p2.getPosition().y - p2.getPoint(i).y + p2.getPosition().y;
normals.add(new Vector(x, y).getNormalVectorLeft());
}
else
{
float x = p2.getPoint(0).x + p2.getPosition().x - p2.getPoint(i).x + p2.getPosition().x;
float y = p2.getPoint(0).y + p2.getPosition().y - p2.getPoint(i).y + p2.getPosition().y;
normals.add(new Vector(x, y).getNormalVectorLeft());
}
}
//project points of p1 and p2 on each normal vector until a gap is found
for (int n = 0; n < normals.size(); n++)
{
ArrayList<Float> projectedPoints1 = new ArrayList<Float>();
ArrayList<Float> projectedPoints2 = new ArrayList<Float>();
for (int i = 0; i < p1.getPointCount(); i++)
projectedPoints1.add(new Vector(p1.getPoint(i).x + p1.getPosition().x, p1.getPoint(i).y + p1.getPosition().y).dot(normals.get(n)));
for (int i = 0; i < p2.getPointCount(); i++)
projectedPoints2.add(new Vector(p2.getPoint(i).x + p2.getPosition().x, p2.getPoint(i).y + p2.getPosition().y).dot(normals.get(n)));
float min1 = getMin(projectedPoints1);
float max1 = getMax(projectedPoints1);
float min2 = getMin(projectedPoints2);
float max2 = getMax(projectedPoints2);
if (max1 < min2 || max2 < min1)
return false;
}
return true;
}
public static float getMin(ArrayList<Float> list)
{
float min = list.get(0);
for (float f : list)
if (f < min)
min = f;
return min;
}
public static float getMax(ArrayList<Float> list)
{
float max = list.get(0);
for (float f : list)
if (f > max)
max = f;
return max;
}
public static void main(String[] args)
{
JFrame frame = new JFrame();
frame.setTitle("SAT");
frame.setLocation(128, 32);
frame.setSize(800, 512);
frame.setContentPane(new Panel());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
private static class Panel extends JPanel implements MouseMotionListener
{
Polygon p1;
Polygon p2;
public Panel()
{
this.p1 = new Polygon();
this.p2 = new Polygon();
this.p1.setPointCount(3);
this.p1.setPoint(0, new Vector(0 * 32, 0 * 32));
this.p1.setPoint(1, new Vector(2 * 32, 3 * 32));
this.p1.setPoint(2, new Vector(0 * 32, 2 * 32));
this.p1.setPosition(128, 128);
this.p2.setPointCount(3);
this.p2.setPoint(0, new Vector(0 * 32, 0 * 32));
this.p2.setPoint(1, new Vector(1 * 32, 2 * 32));
this.p2.setPoint(2, new Vector(0 * 32, 2 * 32));
this.p2.setPosition(128, 128);
this.addMouseMotionListener(this);
}
public void paintComponent(Graphics g)
{
super.paintComponent(g);
if (SAT(p1, p2))
g.setColor(Color.RED);
else
g.setColor(Color.BLACK);
java.awt.Polygon p;
p = new java.awt.Polygon();
for (int i = 0; i < p1.getPointCount(); i++)
p.addPoint((int) (p1.getPoint(i).x + p1.getPosition().x), (int) (p1.getPoint(i).y + p1.getPosition().y));
g.drawPolygon(p);
p = new java.awt.Polygon();
for (int i = 0; i < p2.getPointCount(); i++)
p.addPoint((int) (p2.getPoint(i).x + p2.getPosition().x), (int) (p2.getPoint(i).y + p2.getPosition().y));
g.drawPolygon(p);
}
public void mouseDragged(MouseEvent e)
{
return;
}
public void mouseMoved(MouseEvent e)
{
p2.setPosition(e.getX(), e.getY());
repaint();
}
}
private static class Polygon
{
private Vector[] points;
private Vector position;
public Polygon()
{
this.points = new Vector[0];
}
public void setPointCount(int n)
{
points = new Vector[n];
}
public void setPoint(int i, Vector v)
{
points[i] = v;
}
public void setPosition(float x, float y)
{
position = new Vector(x, y);
}
public Vector getPoint(int i)
{
return points[i];
}
public Vector getPosition()
{
return position;
}
public int getPointCount()
{
return points.length;
}
}
private static class Vector
{
public final float x;
public final float y;
public Vector(float x, float y)
{
this.x = x;
this.y = y;
}
public float dot(Vector v)
{
return x * v.x + y * v.y;
}
public float length()
{
return (float) Math.sqrt(x * x + y * y);
}
public Vector normalize()
{
float l = length();
return new Vector(x/l, y/l);
}
public Vector getNormalVectorLeft()
{
return new Vector(-y, x);
}
public Vector getNormalVectorRight()
{
return new Vector(y, -x);
}
}
}
答えに間違いの説明を追加してください。 –