Computer graphics -- 2007-2008 -- info.uvt.ro/Laboratory 6

[...]
 
	public void init(GLAutoDrawable canvas)
	{
		GL gl = canvas.getGL();
 
		this.glu = new GLU();
		this.glut = new GLUT();
 
		gl.glClearColor(0, 0, 0, 0);
 
		gl.glEnable(GL.GL_DEPTH_TEST);
		gl.glDepthFunc(GL.GL_NICEST);
 
		gl.glShadeModel(GL.GL_SMOOTH);
 
		try {
			this.texture1 = TextureIO.newTexture (new File("./data/ground.jpeg"), true);
			this.texture2 = TextureIO.newTexture (new File("./data/clouds.jpeg"), true);
		} catch (IOException exception) {
			exception.printStackTrace();
			System.exit(1);
		}
 
		this.texture1.setTexParameteri(GL.GL_TEXTURE_MIN_FILTER, GL.GL_LINEAR);
		this.texture2.setTexParameteri(GL.GL_TEXTURE_MAG_FILTER, GL.GL_LINEAR);
	}
 
[...]
 
	public void displayChanged(GLAutoDrawable canvas, boolean modeChanged, boolean deviceChanged)
	{
		return;
	}
 
	public void display(GLAutoDrawable canvas)
	{
		GL gl = canvas.getGL();
 
		gl.glClear(GL.GL_COLOR_BUFFER_BIT);
		gl.glClear(GL.GL_DEPTH_BUFFER_BIT);
 
		gl.glPushMatrix();
 
			gl.glTexEnvf(GL.GL_TEXTURE_ENV, GL.GL_TEXTURE_ENV_MODE, GL.GL_REPLACE);
 
			gl.glEnable(GL.GL_CULL_FACE);
 
			gl.glEnable(GL.GL_TEXTURE_2D);
 
			gl.glDisable(GL.GL_BLEND);
 
			gl.glPushMatrix();
				gl.glRotated(this.angle, 0, 1, 0);
				gl.glRotated(90, 1, 0, 0);
				this.texture1.bind();
				GLUquadric ground = glu.gluNewQuadric();
				glu.gluQuadricTexture(ground, true);
				glu.gluSphere(ground, 0.5, 64, 64);
				glu.gluDeleteQuadric(ground);
			gl.glPopMatrix();
 
			gl.glEnable(GL.GL_BLEND);
			gl.glBlendFunc(GL.GL_SRC_COLOR, GL.GL_DST_ALPHA);
 
			gl.glPushMatrix();
				gl.glRotated(-this.angle, 0, 1, 0);
				gl.glRotated(90, 1, 0, 0);
				this.texture2.bind();
				GLUquadric clouds = glu.gluNewQuadric();
				glu.gluQuadricTexture(clouds, true);
				glu.gluSphere(clouds, 0.52, 64, 64);
				glu.gluDeleteQuadric(clouds);
			gl.glPopMatrix();
 
		gl.glPopMatrix();
 
		gl.glFlush();
 
		this.angle += 3;
	}
 
	private double angle;
[...]

[...]
	public void display(GLAutoDrawable canvas)
	{
		GL gl = canvas.getGL();
 
		gl.glClear(GL.GL_COLOR_BUFFER_BIT);
		gl.glClear(GL.GL_DEPTH_BUFFER_BIT);
 
		this.updateCoordinates();
 
		gl.glPushMatrix();
 
			gl.glTexEnvf(GL.GL_TEXTURE_ENV, GL.GL_TEXTURE_ENV_MODE, GL.GL_REPLACE);
			gl.glEnable (GL.GL_TEXTURE_2D);
			this.bbTexture.bind();
 
			gl.glBegin(GL.GL_QUADS);
				gl.glTexCoord2d(0, 1);
				gl.glVertex3dv(this.bbV1, 0);
				gl.glTexCoord2d(1, 1);
				gl.glVertex3dv(this.bbV2, 0);
				gl.glTexCoord2d(1, 0);
				gl.glVertex3dv(this.bbV3, 0);
				gl.glTexCoord2d(0, 0);
				gl.glVertex3dv(this.bbV4, 0);
			gl.glEnd();
 
		gl.glPopMatrix();
 
		gl.glFlush();
	}
 
	private void updateCoordinates()
	{
		this.bbAngle += this.bbAngleDirection * this.bbAngleSpeed;
		if (this.bbAngle > 13)
			this.bbAngleDirection = -1;
		if (this.bbAngle < -13)
			this.bbAngleDirection = 1;
 
		this.bbDistance = 10;
 
		this.bbCx = Math.cos((90 + this.bbAngle) / 180 * Math.PI) * this.bbDistance;
		this.bbCy = 0;
		this.bbCz = Math.sin((90 + this.bbAngle) / 180 * Math.PI) * this.bbDistance;
 
		this.camCx = 0;
		this.camCy = 0;
		this.camCz = 0;
 
		this.bbV1 = new double[] {this.bbCx - 1, this.bbCy - 1, this.bbCz};
		this.bbV2 = new double[] {this.bbCx + 1, this.bbCy - 1, this.bbCz};
		this.bbV3 = new double[] {this.bbCx + 1, this.bbCy + 1, this.bbCz};
		this.bbV4 = new double[] {this.bbCx - 1, this.bbCy + 1, this.bbCz};
 
		double deltaX = -1 * (this.bbCx - this.camCx);
		double deltaY = -1 * (this.bbCy - this.camCy);
		double deltaZ = -1 * (this.bbCz - this.camCz);
 
		double alpha = Math.atan2(deltaZ, deltaX) - Math.PI / 2.0;
		double beta = Math.atan2(deltaY, Math.sqrt(deltaX * deltaX + deltaZ * deltaZ));
 
		this.bbV1 = this.rotate(this.bbV1, alpha, beta);
		this.bbV2 = this.rotate(this.bbV2, alpha, beta);
		this.bbV3 = this.rotate(this.bbV3, alpha, beta);
		this.bbV4 = this.rotate(this.bbV4, alpha, beta);
	}
 
	public double[] rotate(double[] v, double alpha, double beta)
	{
		double y = v[1]  * Math.cos(beta) + v[2] * Math.sin(beta);
		double z = -v[1] * Math.sin(beta) + v[2] * Math.cos(beta);
		double x = v[0]  * Math.cos(alpha) - z * Math.sin(alpha);
		z = v[0]  * Math.sin(alpha) + z	* Math.cos(alpha);
		return (new double [] {x, y, z});
	}
 
	private double camCx;
	private double camCy;
	private double camCz;
 
	private double bbAngle = 0;
	private double bbAngleDirection = 1;
	private double bbAngleSpeed = 0.5;
	private double bbDistance = 25;
 
	private double bbCx;
	private double bbCy;
	private double bbCz;
 
	private double bbDx;
	private double bbDy;
	private double bbDz;
 
	private double[] bbV1;
	private double[] bbV2;
	private double[] bbV3;
	private double[] bbV4;
[...]