/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.glview.libgdx.graphics.math;
import java.io.Serializable;
/** A 3x3 <a href="http://en.wikipedia.org/wiki/Row-major_order#Column-major_order">column major</a> matrix; useful for 2D transforms.
*
* @author mzechner */
public class Matrix3 implements Serializable {
private static final long serialVersionUID = 7907569533774959788L;
private final static float DEGREE_TO_RAD = (float)Math.PI / 180;
public static final int M00 = 0;
public static final int M01 = 3;
public static final int M02 = 6;
public static final int M10 = 1;
public static final int M11 = 4;
public static final int M12 = 7;
public static final int M20 = 2;
public static final int M21 = 5;
public static final int M22 = 8;
public float[] val = new float[9];
private float[] tmp = new float[9];
public Matrix3 () {
idt();
}
public Matrix3 (Matrix3 matrix) {
set(matrix);
}
/** Constructs a matrix from the given float array. The array must have at least 9 elements; the first 9 will be copied.
* @param values The float array to copy. Remember that this matrix is in
* <a href="http://en.wikipedia.org/wiki/Row-major_order#Column-major_order">column major</a> order.
* (The float array is not modified.) */
public Matrix3 (float[] values) {
this.set(values);
}
/** Sets this matrix to the identity matrix
* @return This matrix for the purpose of chaining operations. */
public Matrix3 idt () {
val[M00] = 1;
val[M10] = 0;
val[M20] = 0;
val[M01] = 0;
val[M11] = 1;
val[M21] = 0;
val[M02] = 0;
val[M12] = 0;
val[M22] = 1;
return this;
}
/** Postmultiplies this matrix with the provided matrix and stores the result in this matrix. For example:
*
* <pre>
* A.mul(B) results in A := AB
* </pre>
* @param m Matrix to multiply by.
* @return This matrix for the purpose of chaining operations together. */
public Matrix3 mul (Matrix3 m) {
float v00 = val[M00] * m.val[M00] + val[M01] * m.val[M10] + val[M02] * m.val[M20];
float v01 = val[M00] * m.val[M01] + val[M01] * m.val[M11] + val[M02] * m.val[M21];
float v02 = val[M00] * m.val[M02] + val[M01] * m.val[M12] + val[M02] * m.val[M22];
float v10 = val[M10] * m.val[M00] + val[M11] * m.val[M10] + val[M12] * m.val[M20];
float v11 = val[M10] * m.val[M01] + val[M11] * m.val[M11] + val[M12] * m.val[M21];
float v12 = val[M10] * m.val[M02] + val[M11] * m.val[M12] + val[M12] * m.val[M22];
float v20 = val[M20] * m.val[M00] + val[M21] * m.val[M10] + val[M22] * m.val[M20];
float v21 = val[M20] * m.val[M01] + val[M21] * m.val[M11] + val[M22] * m.val[M21];
float v22 = val[M20] * m.val[M02] + val[M21] * m.val[M12] + val[M22] * m.val[M22];
val[M00] = v00;
val[M10] = v10;
val[M20] = v20;
val[M01] = v01;
val[M11] = v11;
val[M21] = v21;
val[M02] = v02;
val[M12] = v12;
val[M22] = v22;
return this;
}
/** Sets this matrix to a rotation matrix that will rotate any vector in counter-clockwise direction around the z-axis.
* @param degrees the angle in degrees.
* @return This matrix for the purpose of chaining operations. */
public Matrix3 setToRotation (float degrees) {
float angle = DEGREE_TO_RAD * degrees;
float cos = (float)Math.cos(angle);
float sin = (float)Math.sin(angle);
this.val[M00] = cos;
this.val[M10] = sin;
this.val[M20] = 0;
this.val[M01] = -sin;
this.val[M11] = cos;
this.val[M21] = 0;
this.val[M02] = 0;
this.val[M12] = 0;
this.val[M22] = 1;
return this;
}
/** Sets this matrix to a translation matrix.
* @param x the translation in x
* @param y the translation in y
* @return This matrix for the purpose of chaining operations. */
public Matrix3 setToTranslation (float x, float y) {
this.val[M00] = 1;
this.val[M10] = 0;
this.val[M20] = 0;
this.val[M01] = 0;
this.val[M11] = 1;
this.val[M21] = 0;
this.val[M02] = x;
this.val[M12] = y;
this.val[M22] = 1;
return this;
}
/** Sets this matrix to a translation matrix.
* @param translation The translation vector.
* @return This matrix for the purpose of chaining operations. */
public Matrix3 setToTranslation (Vector2 translation) {
this.val[M00] = 1;
this.val[M10] = 0;
this.val[M20] = 0;
this.val[M01] = 0;
this.val[M11] = 1;
this.val[M21] = 0;
this.val[M02] = translation.x;
this.val[M12] = translation.y;
this.val[M22] = 1;
return this;
}
/** Sets this matrix to a scaling matrix.
*
* @param scaleX the scale in x
* @param scaleY the scale in y
* @return This matrix for the purpose of chaining operations. */
public Matrix3 setToScaling (float scaleX, float scaleY) {
val[M00] = scaleX;
val[M10] = 0;
val[M20] = 0;
val[M01] = 0;
val[M11] = scaleY;
val[M21] = 0;
val[M02] = 0;
val[M12] = 0;
val[M22] = 1;
return this;
}
public String toString () {
return "[" + val[0] + "|" + val[3] + "|" + val[6] + "]\n" + "[" + val[1] + "|" + val[4] + "|" + val[7] + "]\n" + "["
+ val[2] + "|" + val[5] + "|" + val[8] + "]";
}
/** @return The determinant of this matrix */
public float det () {
return val[M00] * val[M11] * val[M22] + val[M01] * val[M12] * val[M20] + val[M02] * val[M10] * val[M21] - val[M00]
* val[M12] * val[M21] - val[M01] * val[M10] * val[M22] - val[M02] * val[M11] * val[M20];
}
/** Inverts this matrix given that the determinant is != 0.
* @return This matrix for the purpose of chaining operations.
* @throws GdxRuntimeException if the matrix is singular (not invertible) */
public Matrix3 inv () {
float det = det();
//if (det == 0) throw new GdxRuntimeException("Can't invert a singular matrix");
float inv_det = 1.0f / det;
tmp[M00] = val[M11] * val[M22] - val[M21] * val[M12];
tmp[M10] = val[M20] * val[M12] - val[M10] * val[M22];
tmp[M20] = val[M10] * val[M21] - val[M20] * val[M11];
tmp[M01] = val[M21] * val[M02] - val[M01] * val[M22];
tmp[M11] = val[M00] * val[M22] - val[M20] * val[M02];
tmp[M21] = val[M20] * val[M01] - val[M00] * val[M21];
tmp[M02] = val[M01] * val[M12] - val[M11] * val[M02];
tmp[M12] = val[M10] * val[M02] - val[M00] * val[M12];
tmp[M22] = val[M00] * val[M11] - val[M10] * val[M01];
val[M00] = inv_det * tmp[M00];
val[M10] = inv_det * tmp[M10];
val[M20] = inv_det * tmp[M20];
val[M01] = inv_det * tmp[M01];
val[M11] = inv_det * tmp[M11];
val[M21] = inv_det * tmp[M21];
val[M02] = inv_det * tmp[M02];
val[M12] = inv_det * tmp[M12];
val[M22] = inv_det * tmp[M22];
return this;
}
/** Copies the values from the provided matrix to this matrix.
* @param mat The matrix to copy.
* @return This matrix for the purposes of chaining. */
public Matrix3 set (Matrix3 mat) {
System.arraycopy(mat.val, 0, val, 0, val.length);
return this;
}
/** Sets this 3x3 matrix to the top left 3x3 corner of the provided 4x4 matrix.
* @param mat The matrix whose top left corner will be copied. This matrix will not be modified.
* @return This matrix for the purpose of chaining operations. */
public Matrix3 set (Matrix4 mat) {
val[M00] = mat.val[Matrix4.M00];
val[M10] = mat.val[Matrix4.M10];
val[M20] = mat.val[Matrix4.M20];
val[M01] = mat.val[Matrix4.M01];
val[M11] = mat.val[Matrix4.M11];
val[M21] = mat.val[Matrix4.M21];
val[M02] = mat.val[Matrix4.M02];
val[M12] = mat.val[Matrix4.M12];
val[M22] = mat.val[Matrix4.M22];
return this;
}
/** Sets the matrix to the given matrix as a float array. The float array must have at least 9 elements; the first 9 will be
* copied.
*
* @param values The matrix, in float form, that is to be copied. Remember that this matrix is in <a
* href="http://en.wikipedia.org/wiki/Row-major_order#Column-major_order">column major</a> order.
* @return This matrix for the purpose of chaining methods together. */
public Matrix3 set (float[] values) {
System.arraycopy(values, 0, val, 0, val.length);
return this;
}
/** Adds a translational component to the matrix in the 3rd column. The other columns are untouched.
* @param vector The translation vector.
* @return This matrix for the purpose of chaining. */
public Matrix3 trn (Vector2 vector) {
val[M02] += vector.x;
val[M12] += vector.y;
return this;
}
/** Adds a translational component to the matrix in the 3rd column. The other columns are untouched.
* @param x The x-component of the translation vector.
* @param y The y-component of the translation vector.
* @return This matrix for the purpose of chaining. */
public Matrix3 trn (float x, float y) {
val[M02] += x;
val[M12] += y;
return this;
}
/** Adds a translational component to the matrix in the 3rd column. The other columns are untouched.
* @param vector The translation vector. (The z-component of the vector is ignored because this is a 3x3 matrix)
* @return This matrix for the purpose of chaining. */
public Matrix3 trn (Vector3 vector) {
val[M02] += vector.x;
val[M12] += vector.y;
return this;
}
/** Postmultiplies this matrix by a translation matrix. Postmultiplication is also used by OpenGL ES' 1.x
* glTranslate/glRotate/glScale.
* @param x The x-component of the translation vector.
* @param y The y-component of the translation vector.
* @return This matrix for the purpose of chaining. */
public Matrix3 translate (float x, float y) {
tmp[M00] = 1;
tmp[M10] = 0;
tmp[M20] = 0;
tmp[M01] = 0;
tmp[M11] = 1;
tmp[M21] = 0;
tmp[M02] = x;
tmp[M12] = y;
tmp[M22] = 1;
mul(val, tmp);
return this;
}
/** Postmultiplies this matrix by a translation matrix. Postmultiplication is also used by OpenGL ES' 1.x
* glTranslate/glRotate/glScale.
* @param translation The translation vector.
* @return This matrix for the purpose of chaining. */
public Matrix3 translate (Vector2 translation) {
tmp[M00] = 1;
tmp[M10] = 0;
tmp[M20] = 0;
tmp[M01] = 0;
tmp[M11] = 1;
tmp[M21] = 0;
tmp[M02] = translation.x;
tmp[M12] = translation.y;
tmp[M22] = 1;
mul(val, tmp);
return this;
}
/** Postmultiplies this matrix with a (counter-clockwise) rotation matrix. Postmultiplication is also used by OpenGL ES' 1.x
* glTranslate/glRotate/glScale.
* @param degrees The angle in degrees
* @return This matrix for the purpose of chaining. */
public Matrix3 rotate (float degrees) {
if (degrees == 0) return this;
degrees = DEGREE_TO_RAD * degrees;
float cos = (float)Math.cos(degrees);
float sin = (float)Math.sin(degrees);
tmp[M00] = cos;
tmp[M10] = sin;
tmp[M20] = 0;
tmp[M01] = -sin;
tmp[M11] = cos;
tmp[M21] = 0;
tmp[M02] = 0;
tmp[M12] = 0;
tmp[M22] = 1;
mul(val, tmp);
return this;
}
/** Postmultiplies this matrix with a scale matrix. Postmultiplication is also used by OpenGL ES' 1.x
* glTranslate/glRotate/glScale.
* @param scaleX The scale in the x-axis.
* @param scaleY The scale in the y-axis.
* @return This matrix for the purpose of chaining. */
public Matrix3 scale (float scaleX, float scaleY) {
tmp[M00] = scaleX;
tmp[M10] = 0;
tmp[M20] = 0;
tmp[M01] = 0;
tmp[M11] = scaleY;
tmp[M21] = 0;
tmp[M02] = 0;
tmp[M12] = 0;
tmp[M22] = 1;
mul(val, tmp);
return this;
}
/** Postmultiplies this matrix with a scale matrix. Postmultiplication is also used by OpenGL ES' 1.x
* glTranslate/glRotate/glScale.
* @param scale The vector to scale the matrix by.
* @return This matrix for the purpose of chaining. */
public Matrix3 scale (Vector2 scale) {
tmp[M00] = scale.x;
tmp[M10] = 0;
tmp[M20] = 0;
tmp[M01] = 0;
tmp[M11] = scale.y;
tmp[M21] = 0;
tmp[M02] = 0;
tmp[M12] = 0;
tmp[M22] = 1;
mul(val, tmp);
return this;
}
/** Get the values in this matrix.
* @return The float values that make up this matrix in column-major order. */
public float[] getValues () {
return val;
}
/** Scale the matrix in the both the x and y components by the scalar value.
* @param scale The single value that will be used to scale both the x and y components.
* @return This matrix for the purpose of chaining methods together. */
public Matrix3 scl (float scale) {
val[M00] *= scale;
val[M11] *= scale;
return this;
}
/** Scale this matrix using the x and y components of the vector but leave the rest of the matrix alone.
* @param scale The {@link Vector3} to use to scale this matrix.
* @return This matrix for the purpose of chaining methods together. */
public Matrix3 scl (Vector2 scale) {
val[M00] *= scale.x;
val[M11] *= scale.y;
return this;
}
/** Scale this matrix using the x and y components of the vector but leave the rest of the matrix alone.
* @param scale The {@link Vector3} to use to scale this matrix. The z component will be ignored.
* @return This matrix for the purpose of chaining methods together. */
public Matrix3 scl (Vector3 scale) {
val[M00] *= scale.x;
val[M11] *= scale.y;
return this;
}
/** Transposes the current matrix.
* @return This matrix for the purpose of chaining methods together. */
public Matrix3 transpose () {
// Where MXY you do not have to change MXX
float v01 = val[M10];
float v02 = val[M20];
float v10 = val[M01];
float v12 = val[M21];
float v20 = val[M02];
float v21 = val[M12];
val[M01] = v01;
val[M02] = v02;
val[M10] = v10;
val[M12] = v12;
val[M20] = v20;
val[M21] = v21;
return this;
}
/** Multiplies matrix a with matrix b in the following manner:
*
* <pre>
* mul(A, B) => A := AB
* </pre>
* @param mata The float array representing the first matrix. Must have at least 9 elements.
* @param matb The float array representing the second matrix. Must have at least 9 elements. */
private static void mul (float[] mata, float[] matb) {
float v00 = mata[M00] * matb[M00] + mata[M01] * matb[M10] + mata[M02] * matb[M20];
float v01 = mata[M00] * matb[M01] + mata[M01] * matb[M11] + mata[M02] * matb[M21];
float v02 = mata[M00] * matb[M02] + mata[M01] * matb[M12] + mata[M02] * matb[M22];
float v10 = mata[M10] * matb[M00] + mata[M11] * matb[M10] + mata[M12] * matb[M20];
float v11 = mata[M10] * matb[M01] + mata[M11] * matb[M11] + mata[M12] * matb[M21];
float v12 = mata[M10] * matb[M02] + mata[M11] * matb[M12] + mata[M12] * matb[M22];
float v20 = mata[M20] * matb[M00] + mata[M21] * matb[M10] + mata[M22] * matb[M20];
float v21 = mata[M20] * matb[M01] + mata[M21] * matb[M11] + mata[M22] * matb[M21];
float v22 = mata[M20] * matb[M02] + mata[M21] * matb[M12] + mata[M22] * matb[M22];
mata[M00] = v00;
mata[M10] = v10;
mata[M20] = v20;
mata[M01] = v01;
mata[M11] = v11;
mata[M21] = v21;
mata[M02] = v02;
mata[M12] = v12;
mata[M22] = v22;
}
}