Miscellany

	public void quad(GL gl, float[][] v)	{		float[] out = new float[3];		calcNormal(v, out);				gl.glBegin(GL.GL_QUADS);			gl.glNormal3f(out[0], out[1], out[2]);			for (int i=0; i < 4; i++)			{				gl.glVertex3d(v[i][0], v[i][1], v[i][2]);			}		gl.glEnd();	}		public void calcNormal(float[][] v, float[] out)	{		float[] v1 = new float[3];		float[] v2 = new float[3];		int x = 0;		int y = 0;		int z = 0;				//point-difference formula (finds vector)		v1[x] = v[0][x] - v[1][x];		v1[y] = v[0][y] - v[1][y];		v1[z] = v[0][z] - v[1][z];				//calculate vector from point 1 to point 0		v2[x] = v[1][x] - v[2][x];		v2[y] = v[1][y] - v[2][y];		v2[z] = v[1][z] - v[2][z];				//cross product to give surface normal		out[x] = v1[y]*v2[z] - v1[z]*v2[y];		out[y] = v1[z]*v2[x] - v1[x]*v2[z];		out[z] = v1[x]*v2[y] - v1[y]*v2[x];				reduceToUnit(out);	}		public void reduceToUnit(float[] vector)	{		float length;		length = (float)Math.sqrt((vector[0]*vector[0]) + (vector[1]*vector[1]) + (vector[2]*vector[2]));				if (length == 0.0) { length = 1.0f; }				vector[0] /= length;		vector[1] /= length;		vector[2] /= length;	}