Collision Detection between two images in Java

Question

I have two characters displayed in a game I am writing, the player and the enemy. defined as such:

public void player(Graphics g) {
    g.drawImage(plimg, x,         


        

Answer 1

Here's the main class from my collision detection program.
You can see it run at: http://www.youtube.com/watch?v=JIXhCvXgjsQ

/**
 *
 * @author Tyler Griffin
 */
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.GraphicsDevice.*;
import java.util.ArrayList;
import java.awt.Graphics;
import java.awt.geom.Line2D;


public class collision extends JFrame implements KeyListener, MouseMotionListener, MouseListener
{
    ArrayList everything=new ArrayList();

    int time=0, x, y, width, height, up=0, down=0, left=0, right=0, mouse1=0, mouse2=0;
    int mouseX, mouseY;

    GraphicsEnvironment environment = GraphicsEnvironment.getLocalGraphicsEnvironment();
    GraphicsDevice screen = environment.getDefaultScreenDevice();
    DisplayMode displayMode = screen.getDisplayMode();

    //private BufferStrategy strategy;

    JLayeredPane pane = new JLayeredPane();

     tile Tile;
     circle Circle;
     rectangle Rectangle;

         textPane text;

    public collision()
    {
        setUndecorated(screen.isFullScreenSupported());
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);
        setLayout(null);
        setResizable(false);
        screen.setFullScreenWindow(this);


        width=displayMode.getWidth();
        height=displayMode.getHeight();


          Circle=new circle(-(int)Math.round((double)height/7*2),-(int)Math.round((double)height/7*2),(int)Math.round((double)height/7*.85),this);
          Rectangle=new rectangle(-(int)Math.round((double)height/7*1.5),-(int)Math.round((double)height/7*1.5),(int)Math.round((double)height/7*1.5),(int)Math.round((double)height/7*1.5),this);
          Tile=Circle;
          Tile.move(mouseX-Tile.width/2, mouseY-Tile.height/2);
                  text=new textPane(0,0,width,height,this);

          everything.add(new circle((int)Math.round((double)width/100*75),(int)Math.round((double)height/100*15),(int)Math.round((double)width/100*10),this));
                  everything.add(new rectangle((int)Math.round((double)width/100*70),(int)Math.round((double)height/100*60),(int)Math.round((double)width/100*20),(int)Math.round((double)height/100*20),this));
                  //everything.add(new line(750,250,750,750,this));
                  /*everything.add(new line(width/700*419,height/700*68,width/700*495,height/700*345,this));
                  everything.add(new line(width/700*495,height/700*345,width/700*749,height/700*350,this));
                  everything.add(new line(width/700*749,height/700*350,width/700*549,height/700*519,this));
                  everything.add(new line(width/700*549,height/700*519,width/700*624,height/700*800,this));
                  everything.add(new line(width/700*624,height/700*800,width/700*419,height/700*638,this));
                  everything.add(new line(width/700*419,height/700*638,width/700*203,height/700*800,this));
                  everything.add(new line(width/700*203,height/700*800,width/700*279,height/700*519,this));
                  everything.add(new line(width/700*279,height/700*519,width/700*76,height/700*350,this));
                  everything.add(new line(width/700*76,height/700*350,width/700*333,height/700*345,this));
                  everything.add(new line(width/700*333,height/700*345,width/700*419,height/700*68,this));

                  everything.add(new line(width/950*419,height/700*68,width/950*624,height/700*800,this));
                  everything.add(new line(width/950*419,height/700*68,width/950*203,height/700*800,this));
                  everything.add(new line(width/950*76,height/700*350,width/950*624,height/700*800,this));
                  everything.add(new line(width/950*203,height/700*800,width/950*749,height/700*350,this));
                  everything.add(new rectangle(width/950*76,height/700*350,width/950*673,1,this));*/

                  everything.add(new line((int)Math.round((double)width/1350*419),(int)Math.round((double)height/1000*68),(int)Math.round((double)width/1350*624),(int)Math.round((double)height/1000*800),this));
                  everything.add(new line((int)Math.round((double)width/1350*419),(int)Math.round((double)height/1000*68),(int)Math.round((double)width/1350*203),(int)Math.round((double)height/1000*800),this));
                  everything.add(new line((int)Math.round((double)width/1350*76),(int)Math.round((double)height/1000*350),(int)Math.round((double)width/1350*624),(int)Math.round((double)height/1000*800),this));
                  everything.add(new line((int)Math.round((double)width/1350*203),(int)Math.round((double)height/1000*800),(int)Math.round((double)width/1350*749),(int)Math.round((double)height/1000*350),this));
                  everything.add(new rectangle((int)Math.round((double)width/1350*76),(int)Math.round((double)height/1000*350),(int)Math.round((double)width/1350*673),1,this));


        addKeyListener(this);
        addMouseMotionListener(this);
        addMouseListener(this);
    }

    public void keyReleased(KeyEvent e)
    {
        Object source=e.getSource();

        int released=e.getKeyCode();

        if (released==KeyEvent.VK_A){left=0;}
        if (released==KeyEvent.VK_W){up=0;}
        if (released==KeyEvent.VK_D){right=0;}
        if (released==KeyEvent.VK_S){down=0;}
    }//end keyReleased


    public void keyPressed(KeyEvent e)
    {
        Object source=e.getSource();

        int pressed=e.getKeyCode();

        if (pressed==KeyEvent.VK_A){left=1;}
        if (pressed==KeyEvent.VK_W){up=1;}
        if (pressed==KeyEvent.VK_D){right=1;}
        if (pressed==KeyEvent.VK_S){down=1;}

        if (pressed==KeyEvent.VK_PAUSE&&pressed==KeyEvent.VK_P)
        {
            //if (paused==0){paused=1;}
            //else paused=0;
        }
    }//end keyPressed

    public void keyTyped(KeyEvent e){}

//***********************************************************************************************

    public void mouseDragged(MouseEvent e)
    {
        mouseX=(e.getX());
        mouseY=(e.getY());

          //run();
    }

    public void mouseMoved(MouseEvent e)
    {
        mouseX=(e.getX());
        mouseY=(e.getY());

          //run();
    }

//***********************************************************************************************

    public void mousePressed(MouseEvent e)
    {
        if(e.getX()==0 && e.getY()==0){System.exit(0);}

    mouseX=(e.getX()+x);
        mouseY=(e.getY()+y);

        if(Tile instanceof circle)
        {
                Circle.move(0-Circle.width, 0-Circle.height);
                Circle.setBounds(Circle.x, Circle.y, Circle.width, Circle.height);
                Tile=Rectangle;
        }
        else
        {
                Rectangle.move(0-Rectangle.width, 0-Rectangle.height);
                Rectangle.setBounds(Rectangle.x, Rectangle.y, Rectangle.width, Rectangle.height);
                Tile=Circle;
        }

        Tile.move(mouseX-Tile.width/2, mouseY-Tile.height/2);
    }

    public void mouseReleased(MouseEvent e)
    {
         //run();
    }

    public void mouseEntered(MouseEvent e){}
    public void mouseExited(MouseEvent e){}

    public void mouseClicked(MouseEvent e){}

//***********************************************************************************************

    public void run()//run collision detection
    {
        while (this == this)
        {
            Tile.move(Tile.x + ((mouseX - (Tile.x + (Tile.width / 2))) / 10), Tile.y + ((mouseY - (Tile.y + (Tile.height / 2))) / 10));
            //Tile.move((mouseX - Tile.width / 2), mouseY - (Tile.height / 2));

            for (int i = 0; i < everything.size(); i++)
            {
                tile Temp = (tile) everything.get(i);

                if (Temp.x < (Tile.x + Tile.width) && (Temp.x + Temp.width) > Tile.x && Temp.y < (Tile.y + Tile.height) && (Temp.y + Temp.height) > Tile.y)//rectangles collided
                {
                    if (Temp instanceof rectangle)
                    {
                        if (Tile instanceof rectangle){rectangleRectangle(Temp);}
                        else {circleRectangle(Temp);}//Tile instanceof circle
                    }
                    else
                    {
                        if (Temp instanceof circle)
                        {
                            if (Tile instanceof rectangle) {rectangleCircle(Temp);}
                            else {circleCircle(Temp);}
                        }
                        else//line
                        {
                            if (Tile instanceof rectangle){rectangleLine(Temp);}
                            else{circleLine(Temp);}
                        }
                    }
                }//end if
            }//end for

            try {Thread.sleep(16L);}
            catch (Exception e) {}

            Tile.setBounds(Tile.x, Tile.y, Tile.width, Tile.height);
            //Rectangle.setBounds(x, y, width, height);
            //Circle.setBounds(x, y, width, height);
            repaint();

            text.out=" ";
        }//end while loop
    }//end run

//***************************************special collision detection/handling functions************************************************

    void rectangleRectangle(tile Temp)
    {
        int lapTop, lapBot, lapLeft, lapRight, small, scootX=0, scootY=0;

        lapTop=(Temp.y+Temp.height)-Tile.y;
        lapBot=(Tile.y+Tile.height)-Temp.y;
        lapLeft=(Temp.x+Temp.width)-Tile.x;
        lapRight=(Tile.x+Tile.width)-Temp.x;

        small=999999999;

        if (lapTop=Temp.x)||(Tile.y+Tile.height/2>=Temp.y && Tile.y+Tile.height/2<=Temp.y+Temp.height))
        {
            rectangleRectangle(Temp);
        }
        else//push from nearest corner
        {
            int x,y;
            if(Tile.x+Tile.width/2>Temp.x+Temp.width && Tile.y+Tile.height/2Temp.x+Temp.width && Tile.y+Tile.height/2>Temp.y+Temp.height){x=Temp.x+Temp.width; y=Temp.y+Temp.height;}
            else {x=Temp.x; y=Temp.y+Temp.height;}

            double distance = Math.sqrt(Math.pow(Tile.x+(Tile.width/2) - x, 2) + Math.pow(Tile.y+(Tile.height/2) - y, 2));

            if((int)Math.round(distance)=Tile.x)||(Temp.y+Temp.height/2>=Tile.y && Temp.y+Temp.height/2<=Tile.y+Tile.height))
        {
            rectangleRectangle(Temp);
        }
        else//push from nearest corner
        {
            int x,y;
            if(Temp.x+Temp.width/2>Tile.x+Tile.width && Temp.y+Temp.height/2Tile.x+Tile.width && Temp.y+Temp.height/2>Tile.y+Tile.height){x=Tile.x+Tile.width; y=Tile.y+Tile.height;}
            else {x=Tile.x; y=Tile.y+Tile.height;}

            double distance = Math.sqrt(Math.pow(Temp.x+(Temp.width/2) - x, 2) + Math.pow(Temp.y+(Temp.height/2) - y, 2));

            if((int)Math.round(distance)Tile.x+Tile.width && Temp.y+Temp.height/2Tile.x+Tile.width && Temp.y+Temp.height/2>Tile.y+Tile.height){Tile.move((Temp.x+Temp.width/2)-(int)Math.round(normX*((Temp.width/2)))-Tile.width,(Temp.y+Temp.height/2)-(int)Math.round(normY*((Temp.height/2)))-Tile.height);text.out="collision detected!";}
                else {Tile.move((Temp.x+Temp.width/2)-(int)Math.round(normX*((Temp.width/2))),(Temp.y+Temp.height/2)-(int)Math.round(normY*((Temp.height/2)))-Tile.height);text.out="collision detected!";}
            }
        }
    }




    void circleCircle(tile Temp)
    {
        double distance = Math.sqrt(Math.pow((Tile.x+(Tile.width/2)) - (Temp.x+(Temp.width/2)),2) + Math.pow((Tile.y+(Tile.height/2)) - (Temp.y+(Temp.height/2)), 2));

        if((int)distance<(Tile.width/2+Temp.width/2))
        {
                        double normX = ((Tile.x+(Tile.width/2)) - (Temp.x+(Temp.width/2))) / distance;
                        double normY = ((Tile.y+(Tile.height/2)) - (Temp.y+(Temp.height/2))) / distance;

            Tile.move((Temp.x+(Temp.width/2))+(int)Math.round(normX*(Tile.width/2+Temp.width/2))-(Tile.width/2) , (Temp.y+(Temp.height/2))+(int)Math.round(normY*(Tile.height/2+Temp.height/2))-(Tile.height/2));text.out="collision detected!";
        }
    }



    void circleLine(tile Temp)
    {
            line Line=(line)Temp;

            if (Line.x1 < (Tile.x + Tile.width) && (Line.x1) > Tile.x && Line.y1 < (Tile.y + Tile.height) && Line.y1 > Tile.y)//circle may be hitting one of the end points
            {
                rectangle rec=new rectangle(Line.x1, Line.y1, 1, 1, this);
                circleRectangle(rec);
                remove(rec);
            }

            if (Line.x2 < (Tile.x + Tile.width) && (Line.x2) > Tile.x && Line.y2 < (Tile.y + Tile.height) && Line.y2 > Tile.y)//circle may be hitting one of the end points
            {
                rectangle rec=new rectangle(Line.x2, Line.y2, 1, 1, this);
                circleRectangle(rec);
                remove(rec);
            }


            int x1=0, y1=0, x2=Tile.x+(Tile.width/2), y2=Tile.y+(Tile.height/2);

            x1=Tile.x+(Tile.width/2)-Line.height;//(int)Math.round(Line.xNorm*1000);
            x2=Tile.x+(Tile.width/2)+Line.height;
            if(Line.posSlope)
            {
                y1=Tile.y+(Tile.height/2)-Line.width;
                y2=Tile.y+(Tile.height/2)+Line.width;
            }
            else
            {
                y1=Tile.y+(Tile.height/2)+Line.width;
                y2=Tile.y+(Tile.height/2)-Line.width;
            }

            Point point=intersection((double)x1,(double)y1,(double)x2,(double)y2,(double)Line.x1,(double)Line.y1,(double)Line.x2,(double)Line.y2);//find intersection

            if (point.x < (Line.x + Line.width) && point.x > Line.x && point.y < (Line.y + Line.height) && point.y > Line.y)//line intersects within line segment
            {
                //if(point!=null){System.out.println(point.x+","+point.y);}
                double distance = Math.sqrt(Math.pow((Tile.x+(Tile.width/2)) - point.x,2) + Math.pow((Tile.y+(Tile.width/2)) - point.y, 2));

                if((int)distance Tile.x && Line.y1 < (Tile.y + Tile.height) && Line.y1 > Tile.y)//circle may be hitting one of the end points
                {
                    rectangle rec=new rectangle(Line.x1, Line.y1, 1, 1, this);
                    rectangleRectangle(rec);
                    remove(rec);
                }

                if (Line.x2 < (Tile.x + Tile.width) && (Line.x2) > Tile.x && Line.y2 < (Tile.y + Tile.height) && Line.y2 > Tile.y)//circle may be hitting one of the end points
                {
                    rectangle rec=new rectangle(Line.x2, Line.y2, 1, 1, this);
                    rectangleRectangle(rec);
                    remove(rec);
                }

                if(Line.posSlope)//positive sloped line
                {
                    //first we'll do the top left corner
                    int x1=Tile.x-Line.height;
                    int x2=Tile.x+Line.height;
                    int y1=Tile.y-Line.width;
                    int y2=Tile.y+Line.width;
                    Point topPoint=new Point(-99,-99), botPoint=new Point(-99,-99);
                    double topDistance=0, botDistance=0;

                    topPoint=intersection((double)x1,(double)y1,(double)x2,(double)y2,(double)Line.x1,(double)Line.y1,(double)Line.x2,(double)Line.y2);//find intersection

                    topDistance = Math.sqrt(Math.pow(Tile.x - topPoint.x,2) + Math.pow(Tile.y - topPoint.y, 2));

                    //new let's do the bottom right corner
                    x1=Tile.x+Tile.width-Line.height;
                    x2=Tile.x+Tile.width+Line.height;
                    y1=Tile.y+Tile.height-Line.width;
                    y2=Tile.y+Tile.height+Line.width;

                    botPoint=intersection((double)x1,(double)y1,(double)x2,(double)y2,(double)Line.x1,(double)Line.y1,(double)Line.x2,(double)Line.y2);//find intersection

                    botDistance = Math.sqrt(Math.pow((Tile.x+Tile.width) - botPoint.x,2) + Math.pow((Tile.y+Tile.height) - botPoint.y, 2));


                    if(topDistance