lwjgl/src/java/org/lwjgl/vector/Matrix2f.java

394 lines
8.8 KiB
Java

/*
* Copyright (c) 2002 Lightweight Java Game Library Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of 'Lightweight Java Game Library' nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.lwjgl.vector;
import java.io.Serializable;
import java.nio.FloatBuffer;
/**
* $Id$
*
* Holds a 2x2 matrix
*
* @author cix_foo <cix_foo@users.sourceforge.net>
* @version $Revision$
*/
public class Matrix2f extends Matrix implements Serializable {
public float m00 = 1.0f, m01, m10, m11 = 1.0f;
/**
* Constructor for Matrix2f.
*/
public Matrix2f() {
}
/**
* Constructor
*/
public Matrix2f(Matrix2f src) {
load(src);
}
/**
* Load from another matrix2f
* @param src The source matrix
* @return this
*/
public Matrix2f load(Matrix2f src) {
m00 = src.m00;
m01 = src.m01;
m10 = src.m10;
m11 = src.m11;
return this;
}
/**
* Load from a float buffer. The buffer stores the matrix in column major
* (OpenGL) order.
*
* @param buf A float buffer to read from
* @return this
*/
public Matrix load(FloatBuffer buf) {
m00 = buf.get();
m01 = buf.get();
m10 = buf.get();
m11 = buf.get();
return this;
}
/**
* Load from a float buffer. The buffer stores the matrix in row major
* (mathematical) order.
*
* @param buf A float buffer to read from
* @return this
*/
public Matrix loadTranspose(FloatBuffer buf) {
m00 = buf.get();
m10 = buf.get();
m01 = buf.get();
m11 = buf.get();
return this;
}
/**
* Store this matrix in a float buffer. The matrix is stored in column
* major (openGL) order.
* @param buf The buffer to store this matrix in
*/
public Matrix store(FloatBuffer buf) {
buf.put(m00);
buf.put(m01);
buf.put(m10);
buf.put(m11);
return this;
}
/**
* Store this matrix in a float buffer. The matrix is stored in row
* major (maths) order.
* @param buf The buffer to store this matrix in
*/
public Matrix storeTranspose(FloatBuffer buf) {
buf.put(m00);
buf.put(m10);
buf.put(m01);
buf.put(m11);
return this;
}
/**
* Add two matrices together and place the result in a third matrix.
* @param left The left source matrix
* @param right The right source matrix
* @param dest The destination matrix, or null if a new one is to be created
* @return the destination matrix
*/
public static Matrix2f add(Matrix2f left, Matrix2f right, Matrix2f dest) {
Matrix2f temp = null;
if (dest == null)
dest = new Matrix2f();
else if (dest == left || dest == right) {
temp = dest;
dest = new Matrix2f();
}
dest.m00 = left.m00 + right.m00;
dest.m01 = left.m01 + right.m01;
dest.m10 = left.m10 + right.m10;
dest.m11 = left.m11 + right.m11;
if (temp != null) {
temp.load(dest);
return temp;
} else
return dest;
}
/**
* Subtract the right matrix from the left and place the result in a third matrix.
* @param left The left source matrix
* @param right The right source matrix
* @param dest The destination matrix, or null if a new one is to be created
* @return the destination matrix
*/
public static Matrix2f sub(Matrix2f left, Matrix2f right, Matrix2f dest) {
Matrix2f temp = null;
if (dest == null)
dest = new Matrix2f();
else if (dest == left || dest == right) {
temp = dest;
dest = new Matrix2f();
}
dest.m00 = left.m00 - right.m00;
dest.m01 = left.m01 - right.m01;
dest.m10 = left.m10 - right.m10;
dest.m11 = left.m11 - right.m11;
if (temp != null) {
temp.load(dest);
return temp;
} else
return dest;
}
/**
* Multiply the right matrix by the left and place the result in a third matrix.
* @param left The left source matrix
* @param right The right source matrix
* @param dest The destination matrix, or null if a new one is to be created
* @return the destination matrix
*/
public static Matrix2f mul(Matrix2f left, Matrix2f right, Matrix2f dest) {
Matrix2f temp = null;
if (dest == null)
dest = new Matrix2f();
else if (dest == left || dest == right) {
temp = dest;
dest = new Matrix2f();
}
dest.m00 = left.m00 * right.m00 + left.m10 * right.m01;
dest.m01 = left.m01 * right.m00 + left.m11 * right.m01;
dest.m10 = left.m00 * right.m10 + left.m10 * right.m11;
dest.m11 = left.m01 * right.m10 + left.m11 * right.m11;
if (temp != null) {
temp.load(dest);
return temp;
} else
return dest;
}
/**
* Transform a Vector by a matrix and return the result in a destination
* vector.
* @param left The left matrix
* @param right The right vector
* @param dest The destination vector, or null if a new one is to be created
* @return the destination vector
*/
public static Vector2f transform(Matrix2f left, Vector2f right, Vector2f dest) {
Vector2f temp = null;
if (dest == null)
dest = new Vector2f();
else if (dest == right) {
temp = dest;
dest = new Vector2f();
}
dest.x = left.m00 * right.x + left.m10 * right.y;
dest.y = left.m01 * right.x + left.m11 * right.y;
if (temp != null) {
temp.set(dest);
return temp;
} else
return dest;
}
/**
* Transpose this matrix
* @return this
*/
public Matrix transpose() {
float temp;
temp = m01;
m01 = m10;
m10 = temp;
return this;
}
/**
* Transpose this matrix and place the result in another matrix.
* @param dest The destination matrix or null if a new matrix is to be created
* @return the transposed matrix
*/
public Matrix2f transpose(Matrix2f dest) {
if (dest == null)
dest = new Matrix2f();
if (dest == this)
transpose();
else {
dest.m01 = m10;
dest.m10 = m01;
}
return dest;
}
/**
* Invert this matrix
* @return this if successful, null otherwise
*/
public Matrix invert()
{
/*
*inv(A) = 1/det(A) * adj(A);
*/
float determinant = determinant();
if (determinant != 0) {
float determinant_inv = 1f/determinant;
float t00 = m11*determinant_inv;
float t01 = -m01*determinant_inv;
float t11 = m00*determinant_inv;
float t10 = -m10*determinant_inv;
m00 = t00;
m01 = t01;
m10 = t10;
m11 = t11;
return this;
} else
return null;
}
/**
* Returns a string representation of this matrix
*/
public String toString() {
StringBuffer buf = new StringBuffer();
buf.append(m00).append(' ').append(m10).append(' ').append('\n');
buf.append(m01).append(' ').append(m11).append(' ').append('\n');
return buf.toString();
}
/**
* Negate this matrix
* @return this
*/
public Matrix negate() {
m00 = -m00;
m01 = -m01;
m10 = -m10;
m11 = -m11;
return this;
}
/**
* Negate this matrix and stash the result in another matrix.
* @param dest The destination matrix, or null if a new matrix is to be created
* @return the negated matrix
*/
public Matrix2f negate(Matrix2f dest) {
if (dest == null)
dest = new Matrix2f();
dest.m00 = -m00;
dest.m01 = -m01;
dest.m10 = -m10;
dest.m11 = -m11;
return dest;
}
/**
* Set this matrix to be the identity matrix.
* @return this
*/
public Matrix setIdentity() {
m00 = 1.0f;
m01 = 0.0f;
m10 = 0.0f;
m11 = 1.0f;
return this;
}
/**
* Set this matrix to 0.
* @return this
*/
public Matrix setZero() {
m00 = 0.0f;
m01 = 0.0f;
m10 = 0.0f;
m11 = 0.0f;
return this;
}
/* (non-Javadoc)
* @see org.lwjgl.vector.Matrix#determinant()
*/
public float determinant() {
return m00 * m11 - m01*m10;
}
}