Matrix33.java

/**
 * Copyright (c) 2009, iPlant Collaborative, Texas Advanced Computing Center
 * This software is licensed under the CC-GNU GPL version 2.0 or later.
 * License: http://creativecommons.org/licenses/GPL/2.0/
 */

package org.iplantc.phyloviewer.shared.math;

import java.util.Arrays;

public class Matrix33 {

	private double[][] m=new double[3][3];

	public Matrix33() {
		this.set(1, 0, 0, 
				 0, 1, 0,
				 0, 0, 1);
	}
	
	public Matrix33(double m00, double m01, double m02, 
	                double m10, double m11, double m12,
	                double m20, double m21, double m22) {
		this.set(m00,m01,m02,
				 m10,m11,m12,
				 m20,m21,m22);
	}
	
	public static Matrix33 makeTranslate(double x, double y) {
		return new Matrix33(1,0,x,
				            0,1,y,
				            0,0,1);
	}
	
	public static Matrix33 makeScale(double sx, double sy ) {
		return new Matrix33(sx,0,0,
				            0,sy,0,
				            0,0,1);
	}
	
	public void set(double m00, double m01, double m02, 
			        double m10, double m11, double m12,
			        double m20, double m21, double m22 ) {	
		m[0][0] = m00; m[0][1] = m01;	m[0][2] = m02;
		m[1][0] = m10;	m[1][1] = m11; m[1][2] = m12;
		m[2][0] = m20; m[2][1] = m21; m[2][2] = m22;
	}
		
	public Vector2 transform(Vector2 vector) {
		double x = m[0][0] * vector.getX() + m[0][1] * vector.getY() + m[0][2];
		double y = m[1][0] * vector.getX() + m[1][1] * vector.getY() + m[1][2];
		
		return new Vector2 ( x, y );
	}
	
	public Box2D transform(Box2D box) {
		Vector2 min = transform(box.getMin());
		Vector2 max = transform(box.getMax());
		return new Box2D(min, max);
	}
	
	public Matrix33 multiply(Matrix33 rhs) {
		double m00 = this.m[0][0] * rhs.m[0][0] + this.m[0][1] * rhs.m[1][0] + this.m[0][2] * rhs.m[2][0];
		double m01 = this.m[0][0] * rhs.m[0][1] + this.m[0][1] * rhs.m[1][1] + this.m[0][2] * rhs.m[2][1];
		double m02 = this.m[0][0] * rhs.m[0][2] + this.m[0][1] * rhs.m[1][2] + this.m[0][2] * rhs.m[2][2];
		
		double m10 = this.m[1][0] * rhs.m[1][0] + this.m[1][1] * rhs.m[1][0] + this.m[1][2] * rhs.m[2][0];
		double m11 = this.m[1][0] * rhs.m[0][1] + this.m[1][1] * rhs.m[1][1] + this.m[1][2] * rhs.m[2][1];
		double m12 = this.m[1][0] * rhs.m[0][2] + this.m[1][1] * rhs.m[1][2] + this.m[1][2] * rhs.m[2][2];
		
		double m20 = this.m[2][0] * rhs.m[1][0] + this.m[2][1] * rhs.m[1][0] + this.m[2][2] * rhs.m[2][0];
		double m21 = this.m[2][0] * rhs.m[0][1] + this.m[2][1] * rhs.m[1][1] + this.m[2][2] * rhs.m[2][1];
		double m22 = this.m[2][0] * rhs.m[0][2] + this.m[2][1] * rhs.m[1][2] + this.m[2][2] * rhs.m[2][2];
		
		return new Matrix33(m00,m01,m02,m10,m11,m12,m20,m21,m22);
	}
	
	public double determinant() {
		
		// Make three column vectors
		Vector3 v0 = new Vector3(m[0][0], m[1][0], m[2][0]);
		Vector3 v1 = new Vector3(m[0][1], m[1][1], m[2][1]);
		Vector3 v2 = new Vector3(m[0][2], m[1][2], m[2][2]);
		
		Vector3 t = v1.cross(v2);
		return v0.dot(t);
	}
	
	public Matrix33 inverse() {
		double det = this.determinant();
		
		if ( det == 0.0 )
			throw new RuntimeException("This matrix is not invertable");
		
		// Make three column vectors
		Vector3 v0 = new Vector3(m[0][0], m[1][0], m[2][0]);
		Vector3 v1 = new Vector3(m[0][1], m[1][1], m[2][1]);
		Vector3 v2 = new Vector3(m[0][2], m[1][2], m[2][2]);
		
		// These are row vectors.
		Vector3 t0 = v1.cross(v2);
		Vector3 t1 = v2.cross(v0);
		Vector3 t2 = v0.cross(v1);
		
		double oneOverDet = 1.0 / det;
		return new Matrix33 ( oneOverDet * t0.getX(), oneOverDet * t0.getY(), oneOverDet * t0.getZ(),
				              oneOverDet * t1.getX(), oneOverDet * t1.getY(), oneOverDet * t1.getZ(),
				              oneOverDet * t2.getX(), oneOverDet * t2.getY(), oneOverDet * t2.getZ());
	}
	
	public void   set(int row, int col,double value) { m[row][col] = value; }
	public double get(int row, int col) { return m[row][col]; }

	public void setTranslationX(double value) { m[0][2]=value; }
	public void setTranslationY(double value) { m[1][2]=value; }
	
	public double getTranslationX() { return m[0][2]; }
	public double getTranslationY() { return m[1][2]; }	
	public double getScaleX() { return m[0][0]; }
	public double getScaleY() { return m[1][1]; }
	public double getShearX() { return m[0][1]; }
	public double getShearY() { return m[1][0]; }
	
	public String toString() {
		StringBuilder sb = new StringBuilder();
		sb.append("[");
		sb.append(Arrays.toString(m[0]));
		sb.append("\n");
		sb.append(Arrays.toString(m[1]));
		sb.append("\n");
		sb.append(Arrays.toString(m[2]));
		sb.append("]");
		
		return sb.toString();
	}
}