Cubo 3D en java.....

El siguiente es un Applet en el que tenemos un cubo, el cual rota en cualquier dirección, mostrándonos  sus coordenadas X, Y.

Ahora el código:

nombre: Cubo.java

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/**

 *

 * @author alex4024

 */

import java.applet.*;

import java.awt.*;

import java.awt.event.*;

import java.lang.Math;

import java.awt.Polygon;

class Point{

public double x;

public double y;

public double z;

Point(){ this.x=0; this.y=0; this.z=0; }

Point(double x,double y, double z){ this.x=x; this.y=y; this.z=z; }

int getXCoordinate(){return Cubo.origin + (int)this.x;}

int getYCoordinate(){return Cubo.origin - (int)this.y;}

int getZCoordinate(){return 0;} 

}

class Face{

Point p1,p2,p3,p4;

Polygon side= new Polygon();

Face(){}

Face(Point p1,Point p2,Point p3,Point p4){

this.p1=p1;this.p2=p2;this.p3=p3;this.p4=p4;

this.side.addPoint(p1.getXCoordinate(),p1.getYCoordinate());

this.side.addPoint(p2.getXCoordinate(),p2.getYCoordinate());

this.side.addPoint(p3.getXCoordinate(),p3.getYCoordinate());

this.side.addPoint(p4.getXCoordinate(),p4.getYCoordinate());

}

public void drawFace(Graphics g){ g.fillPolygon(side); }

public boolean isVisible(){

Point aux1, aux2;

aux1 = new Point(p2.x-p1.x, p2.y-p1.y, p2.z-p1.z); // p1->p2

aux2 = new Point(p4.x-p1.x, p4.y-p1.y, p4.z-p1.z); // p1->p4

if((aux1.x*aux2.y - aux1.y*aux2.x) > 0)

return true;

return false;

}

}

public class Cubo extends Applet implements

Runnable, MouseMotionListener{

Thread luxury;

static Point[] vertex = new Point[8]; 

static int maxSize =300; 

static int origin = maxSize/2;

static int xMouseP=0, yMouseP =0;

int xAux , yAux ; 

int module = 50; 

Image canvasAux;

Graphics backBuffer;

public void init(){

setSize(maxSize,maxSize);

setBackground( new Color(0.2f,0.6f,0.1f,1.0f) );

addMouseMotionListener(this);

int[] coordX = new int[]{-module,module,module,-module,-module,module,module,-module};

int[] coordY = new int[]{-module,-module,module,module,-module,-module,module,module};

int[] coordZ = new int[]{module,module,module,module,-module,-module,-module,-module};

canvasAux = createImage(500,500);

backBuffer = canvasAux.getGraphics();

for(int i =0; i<vertex.length; i++){

vertex[i] = new Point(coordX[i],coordY[i],coordZ[i]);

}

}

public void start(){

try { luxury = new Thread(this); luxury.start(); }

catch (Exception e){}

}

public void run() {}

public void stop(){}

public void paint(Graphics g){

int[] pts1 = new int[]{0,1,5,0,0,3};

int[] pts2 = new int[]{1,5,4,3,4,2};

int[] pts3 = new int[]{2,6,7,7,5,6};

int[] pts4 = new int[]{3,2,6,4,1,7};

Color[] colorRGB = new Color[]{ Color.black, Color.blue,Color.orange,Color.pink,Color.red, Color.yellow};

Face[] faces = new Face[6];

backBuffer.clearRect(0,0,500,500);

for(int i=0; i<6; i++){

backBuffer.setColor(colorRGB[i]);

faces[i] = new 

Face(vertex[pts1[i]],vertex[pts2[i]],vertex[pts3[i]],vertex[pts4[i]]);

if(faces[i].isVisible()){

faces[i].drawFace(backBuffer);

}

}

g.drawImage(canvasAux,0,0,this);

g.drawString(" Coordenadas: ", 30,30);

g.drawString(" X= " + xMouseP, 30,50);

g.drawString(" Y= " + yMouseP, 30,65);

return;

}

public void update(Graphics g){ paint(g); }

public void destroy(){

try {Thread.sleep(1500);}

catch (InterruptedException e) {

System.out.println("Exception in sleep");

}

}

void rota(double angleTeta, double anglePhi, double anglePsi) {

double teta= Math.toRadians(angleTeta);

double phi= Math.toRadians(anglePhi);

double psi= Math.toRadians(anglePsi);

Point pAux = new Point();

Point pAux1 = new Point();

Point pAux2 = new Point();

for(int i =0; i<8; i++){

pAux1.x = vertex[i].x;

pAux1.y= vertex[i].y * Math.cos(teta) + vertex[i].z * (-Math.sin(teta));

pAux1.z = vertex[i].y * Math.sin(teta) + vertex[i].z * Math.cos(teta);

pAux2.x = pAux1.x * Math.cos(phi) + pAux1.z * Math.sin(phi);

pAux2.y = pAux1.y;

pAux2.z = pAux1.x * (-Math.sin(phi)) + pAux1.z * Math.cos(phi);

pAux.x= pAux2.x * Math.cos(psi) + pAux2.y * (-Math.sin(psi));

pAux.y = pAux2.x * Math.sin(psi) + pAux2.y * Math.cos(psi);

pAux.z= pAux2.z;

vertex[i].x = pAux.x;

vertex[i].y = pAux.y;

vertex[i].z = pAux.z;

}

}

public void mouseDragged( MouseEvent e ){

xAux = xMouseP;

yAux = yMouseP;

xMouseP = e.getX();

yMouseP = e.getY();

if(yMouseP > yAux){ rota(2,0,0); }

if(yMouseP < yAux){ rota(-2,0,0); }

if(xMouseP > xAux){ rota(0,2,0); }

if(xMouseP < xAux){ rota(0,-2,0); }

repaint();

e.consume();

}

public void mouseMoved( MouseEvent e ) { }

} 

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