summaryrefslogtreecommitdiffstats
path: root/src/gleem/linalg/Mat2f.java
diff options
context:
space:
mode:
authorKenneth Russel <[email protected]>2003-06-25 09:05:29 +0000
committerKenneth Russel <[email protected]>2003-06-25 09:05:29 +0000
commit2179980ed660ef66a9c064d153c5de7994d431ab (patch)
tree926fa0ccc31737ad9753a64bf0451dd818652d1b /src/gleem/linalg/Mat2f.java
parent1a1ad3a33b2932187410bc8bb4bf44362a26c8b0 (diff)
Split up net.java.games.util; moved GLUT and BufferUtils into
net.java.games.jogl.util, and moved demo-specific utility classes into jogl-demos project under demos.util. Added nearly all JavaOne demos into jogl-demos project; rewrote where necessary to use ClassLoader.getResourceAsStream() instead of flat files, put into packages and added to Makefile. Added gleem to jogl-demos project. Added jogl.jar build rule. git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/../svn-server-sync/jogl-demos/trunk@3 3298f667-5e0e-4b4a-8ed4-a3559d26a5f4
Diffstat (limited to 'src/gleem/linalg/Mat2f.java')
-rw-r--r--src/gleem/linalg/Mat2f.java169
1 files changed, 169 insertions, 0 deletions
diff --git a/src/gleem/linalg/Mat2f.java b/src/gleem/linalg/Mat2f.java
new file mode 100644
index 0000000..6852dbc
--- /dev/null
+++ b/src/gleem/linalg/Mat2f.java
@@ -0,0 +1,169 @@
+/*
+ * gleem -- OpenGL Extremely Easy-To-Use Manipulators.
+ * Copyright (C) 1998-2003 Kenneth B. Russell ([email protected])
+ *
+ * Copying, distribution and use of this software in source and binary
+ * forms, with or without modification, is permitted provided that the
+ * following conditions are met:
+ *
+ * Distributions of source code must reproduce the copyright notice,
+ * this list of conditions and the following disclaimer in the source
+ * code header files; and Distributions of binary code must reproduce
+ * the copyright notice, this list of conditions and the following
+ * disclaimer in the documentation, Read me file, license file and/or
+ * other materials provided with the software distribution.
+ *
+ * The names of Sun Microsystems, Inc. ("Sun") and/or the copyright
+ * holder may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS," WITHOUT A WARRANTY OF ANY
+ * KIND. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
+ * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, NON-INTERFERENCE, ACCURACY OF
+ * INFORMATIONAL CONTENT OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. THE
+ * COPYRIGHT HOLDER, SUN AND SUN'S LICENSORS SHALL NOT BE LIABLE FOR
+ * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
+ * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL THE
+ * COPYRIGHT HOLDER, SUN OR SUN'S LICENSORS BE LIABLE FOR ANY LOST
+ * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
+ * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
+ * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
+ * INABILITY TO USE THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGES. YOU ACKNOWLEDGE THAT THIS SOFTWARE IS NOT
+ * DESIGNED, LICENSED OR INTENDED FOR USE IN THE DESIGN, CONSTRUCTION,
+ * OPERATION OR MAINTENANCE OF ANY NUCLEAR FACILITY. THE COPYRIGHT
+ * HOLDER, SUN AND SUN'S LICENSORS DISCLAIM ANY EXPRESS OR IMPLIED
+ * WARRANTY OF FITNESS FOR SUCH USES.
+ */
+
+package gleem.linalg;
+
+/** 2x2 matrix class useful for simple linear algebra. Representation
+ is (as Mat4f) in row major order and assumes multiplication by
+ column vectors on the right. */
+
+public class Mat2f {
+ private float[] data;
+
+ /** Creates new matrix initialized to the zero matrix */
+ public Mat2f() {
+ data = new float[4];
+ }
+
+ /** Initialize to the identity matrix. */
+ public void makeIdent() {
+ for (int i = 0; i < 2; i++) {
+ for (int j = 0; j < 2; j++) {
+ if (i == j) {
+ set(i, j, 1.0f);
+ } else {
+ set(i, j, 0.0f);
+ }
+ }
+ }
+ }
+
+ /** Gets the (i,j)th element of this matrix, where i is the row
+ index and j is the column index */
+ public float get(int i, int j) {
+ return data[2 * i + j];
+ }
+
+ /** Sets the (i,j)th element of this matrix, where i is the row
+ index and j is the column index */
+ public void set(int i, int j, float val) {
+ data[2 * i + j] = val;
+ }
+
+ /** Set column i (i=[0..1]) to vector v. */
+ public void setCol(int i, Vec2f v) {
+ set(0, i, v.x());
+ set(1, i, v.y());
+ }
+
+ /** Set row i (i=[0..1]) to vector v. */
+ public void setRow(int i, Vec2f v) {
+ set(i, 0, v.x());
+ set(i, 1, v.y());
+ }
+
+ /** Transpose this matrix in place. */
+ public void transpose() {
+ float t = get(0, 1);
+ set(0, 1, get(1, 0));
+ set(1, 0, t);
+ }
+
+ /** Return the determinant. */
+ public float determinant() {
+ return (get(0, 0) * get(1, 1) - get(1, 0) * get(0, 1));
+ }
+
+ /** Full matrix inversion in place. If matrix is singular, returns
+ false and matrix contents are untouched. If you know the matrix
+ is orthonormal, you can call transpose() instead. */
+ public boolean invert() {
+ float det = determinant();
+ if (det == 0.0f)
+ return false;
+
+ // Create transpose of cofactor matrix in place
+ float t = get(0, 0);
+ set(0, 0, get(1, 1));
+ set(1, 1, t);
+ set(0, 1, -get(0, 1));
+ set(1, 0, -get(1, 0));
+
+ // Now divide by determinant
+ for (int i = 0; i < 4; i++) {
+ data[i] /= det;
+ }
+ return true;
+ }
+
+ /** Multiply a 2D vector by this matrix. NOTE: src and dest must be
+ different vectors. */
+ public void xformVec(Vec2f src, Vec2f dest) {
+ dest.set(get(0, 0) * src.x() +
+ get(0, 1) * src.y(),
+
+ get(1, 0) * src.x() +
+ get(1, 1) * src.y());
+ }
+
+ /** Returns this * b; creates new matrix */
+ public Mat2f mul(Mat2f b) {
+ Mat2f tmp = new Mat2f();
+ tmp.mul(this, b);
+ return tmp;
+ }
+
+ /** this = a * b */
+ public void mul(Mat2f a, Mat2f b) {
+ for (int rc = 0; rc < 2; rc++)
+ for (int cc = 0; cc < 2; cc++) {
+ float tmp = 0.0f;
+ for (int i = 0; i < 2; i++)
+ tmp += a.get(rc, i) * b.get(i, cc);
+ set(rc, cc, tmp);
+ }
+ }
+
+ public Matf toMatf() {
+ Matf out = new Matf(2, 2);
+ for (int i = 0; i < 2; i++) {
+ for (int j = 0; j < 2; j++) {
+ out.set(i, j, get(i, j));
+ }
+ }
+ return out;
+ }
+
+ public String toString() {
+ String endl = System.getProperty("line.separator");
+ return "(" +
+ get(0, 0) + ", " + get(0, 1) + endl +
+ get(1, 0) + ", " + get(1, 1) + ")";
+ }
+}