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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/Rotf.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
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+/*
+ * 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;
+
+/** Represents a rotation with single-precision components */
+
+public class Rotf {
+ private static float EPSILON = 1.0e-7f;
+
+ // Representation is a quaternion. Element 0 is the scalar part (=
+ // cos(theta/2)), elements 1..3 the imaginary/"vector" part (=
+ // sin(theta/2) * axis).
+ private float q0;
+ private float q1;
+ private float q2;
+ private float q3;
+
+ /** Default constructor initializes to the identity quaternion */
+ public Rotf() {
+ init();
+ }
+
+ public Rotf(Rotf arg) {
+ set(arg);
+ }
+
+ /** Axis does not need to be normalized but must not be the zero
+ vector. Angle is in radians. */
+ public Rotf(Vec3f axis, float angle) {
+ set(axis, angle);
+ }
+
+ /** Creates a rotation which will rotate vector "from" into vector
+ "to". */
+ public Rotf(Vec3f from, Vec3f to) {
+ set(from, to);
+ }
+
+ /** Re-initialize this quaternion to be the identity quaternion "e"
+ (i.e., no rotation) */
+ public void init() {
+ q0 = 1;
+ q1 = q2 = q3 = 0;
+ }
+
+ /** Test for "approximate equality" -- performs componentwise test
+ to see whether difference between all components is less than
+ epsilon. */
+ public boolean withinEpsilon(Rotf arg, float epsilon) {
+ return ((Math.abs(q0 - arg.q0) < epsilon) &&
+ (Math.abs(q1 - arg.q1) < epsilon) &&
+ (Math.abs(q2 - arg.q2) < epsilon) &&
+ (Math.abs(q3 - arg.q3) < epsilon));
+ }
+
+ /** Axis does not need to be normalized but must not be the zero
+ vector. Angle is in radians. */
+ public void set(Vec3f axis, float angle) {
+ float halfTheta = angle / 2.0f;
+ q0 = (float) Math.cos(halfTheta);
+ float sinHalfTheta = (float) Math.sin(halfTheta);
+ Vec3f realAxis = new Vec3f(axis);
+ realAxis.normalize();
+ q1 = realAxis.x() * sinHalfTheta;
+ q2 = realAxis.y() * sinHalfTheta;
+ q3 = realAxis.z() * sinHalfTheta;
+ }
+
+ public void set(Rotf arg) {
+ q0 = arg.q0;
+ q1 = arg.q1;
+ q2 = arg.q2;
+ q3 = arg.q3;
+ }
+
+ /** Sets this rotation to that which will rotate vector "from" into
+ vector "to". from and to do not have to be the same length. */
+ public void set(Vec3f from, Vec3f to) {
+ Vec3f axis = from.cross(to);
+ if (axis.lengthSquared() < EPSILON) {
+ init();
+ return;
+ }
+ float dotp = from.dot(to);
+ float denom = from.length() * to.length();
+ if (denom < EPSILON) {
+ init();
+ return;
+ }
+ dotp /= denom;
+ set(axis, (float) Math.acos(dotp));
+ }
+
+ /** Returns angle (in radians) and mutates the given vector to be
+ the axis. */
+ public float get(Vec3f axis) {
+ // FIXME: Is this numerically stable? Is there a better way to
+ // extract the angle from a quaternion?
+ // NOTE: remove (float) to illustrate compiler bug
+ float retval = (float) (2.0f * Math.acos(q0));
+ axis.set(q1, q2, q3);
+ float len = axis.length();
+ if (len == 0.0f) {
+ axis.set(0, 0, 1);
+ } else {
+ axis.scale(1.0f / len);
+ }
+ return retval;
+ }
+
+ /** Returns inverse of this rotation; creates new rotation */
+ public Rotf inverse() {
+ Rotf tmp = new Rotf(this);
+ tmp.invert();
+ return tmp;
+ }
+
+ /** Mutate this quaternion to be its inverse. This is equivalent to
+ the conjugate of the quaternion. */
+ public void invert() {
+ q1 = -q1;
+ q2 = -q2;
+ q3 = -q3;
+ }
+
+ /** Length of this quaternion in four-space */
+ public float length() {
+ return (float) Math.sqrt(lengthSquared());
+ }
+
+ /** This dotted with this */
+ public float lengthSquared() {
+ return (q0 * q0 +
+ q1 * q1 +
+ q2 * q2 +
+ q3 * q3);
+ }
+
+ /** Make this quaternion a unit quaternion again. If you are
+ composing dozens of quaternions you probably should call this
+ periodically to ensure that you have a valid rotation. */
+ public void normalize() {
+ float len = length();
+ q0 /= len;
+ q1 /= len;
+ q2 /= len;
+ q3 /= len;
+ }
+
+ /** Returns this * b, in that order; creates new rotation */
+ public Rotf times(Rotf b) {
+ Rotf tmp = new Rotf();
+ tmp.mul(this, b);
+ return tmp;
+ }
+
+ /** Compose two rotations: this = A * B in that order. NOTE that
+ because we assume a column vector representation that this
+ implies that a vector rotated by the cumulative rotation will be
+ rotated first by B, then A. NOTE: "this" must be different than
+ both a and b. */
+ public void mul(Rotf a, Rotf b) {
+ q0 = (a.q0 * b.q0 - a.q1 * b.q1 -
+ a.q2 * b.q2 - a.q3 * b.q3);
+ q1 = (a.q0 * b.q1 + a.q1 * b.q0 +
+ a.q2 * b.q3 - a.q3 * b.q2);
+ q2 = (a.q0 * b.q2 + a.q2 * b.q0 -
+ a.q1 * b.q3 + a.q3 * b.q1);
+ q3 = (a.q0 * b.q3 + a.q3 * b.q0 +
+ a.q1 * b.q2 - a.q2 * b.q1);
+ }
+
+ /** Turns this rotation into a 3x3 rotation matrix. NOTE: only
+ mutates the upper-left 3x3 of the passed Mat4f. Implementation
+ from B. K. P. Horn's <u>Robot Vision</u> textbook. */
+ public void toMatrix(Mat4f mat) {
+ float q00 = q0 * q0;
+ float q11 = q1 * q1;
+ float q22 = q2 * q2;
+ float q33 = q3 * q3;
+ // Diagonal elements
+ mat.set(0, 0, q00 + q11 - q22 - q33);
+ mat.set(1, 1, q00 - q11 + q22 - q33);
+ mat.set(2, 2, q00 - q11 - q22 + q33);
+ // 0,1 and 1,0 elements
+ float q03 = q0 * q3;
+ float q12 = q1 * q2;
+ mat.set(0, 1, 2.0f * (q12 - q03));
+ mat.set(1, 0, 2.0f * (q03 + q12));
+ // 0,2 and 2,0 elements
+ float q02 = q0 * q2;
+ float q13 = q1 * q3;
+ mat.set(0, 2, 2.0f * (q02 + q13));
+ mat.set(2, 0, 2.0f * (q13 - q02));
+ // 1,2 and 2,1 elements
+ float q01 = q0 * q1;
+ float q23 = q2 * q3;
+ mat.set(1, 2, 2.0f * (q23 - q01));
+ mat.set(2, 1, 2.0f * (q01 + q23));
+ }
+
+ /** Turns the upper left 3x3 of the passed matrix into a rotation.
+ Implementation from Watt and Watt, <u>Advanced Animation and
+ Rendering Techniques</u>.
+ @see gleem.linalg.Mat4f#getRotation */
+ public void fromMatrix(Mat4f mat) {
+ // FIXME: Should reimplement to follow Horn's advice of using
+ // eigenvector decomposition to handle roundoff error in given
+ // matrix.
+
+ float tr, s;
+ int i, j, k;
+
+ tr = mat.get(0, 0) + mat.get(1, 1) + mat.get(2, 2);
+ if (tr > 0.0) {
+ s = (float) Math.sqrt(tr + 1.0f);
+ q0 = s * 0.5f;
+ s = 0.5f / s;
+ q1 = (mat.get(2, 1) - mat.get(1, 2)) * s;
+ q2 = (mat.get(0, 2) - mat.get(2, 0)) * s;
+ q3 = (mat.get(1, 0) - mat.get(0, 1)) * s;
+ } else {
+ i = 0;
+ if (mat.get(1, 1) > mat.get(0, 0))
+ i = 1;
+ if (mat.get(2, 2) > mat.get(i, i))
+ i = 2;
+ j = (i+1)%3;
+ k = (j+1)%3;
+ s = (float) Math.sqrt( (mat.get(i, i) - (mat.get(j, j) + mat.get(k, k))) + 1.0f);
+ setQ(i+1, s * 0.5f);
+ s = 0.5f / s;
+ q0 = (mat.get(k, j) - mat.get(j, k)) * s;
+ setQ(j+1, (mat.get(j, i) + mat.get(i, j)) * s);
+ setQ(k+1, (mat.get(k, i) + mat.get(i, k)) * s);
+ }
+ }
+
+ /** Rotate a vector by this quaternion. Implementation is from
+ Horn's <u>Robot Vision</u>. NOTE: src and dest must be different
+ vectors. */
+ public void rotateVector(Vec3f src, Vec3f dest) {
+ Vec3f qVec = new Vec3f(q1, q2, q3);
+ Vec3f qCrossX = qVec.cross(src);
+ Vec3f qCrossXCrossQ = qCrossX.cross(qVec);
+ qCrossX.scale(2.0f * q0);
+ qCrossXCrossQ.scale(-2.0f);
+ dest.add(src, qCrossX);
+ dest.add(dest, qCrossXCrossQ);
+ }
+
+ /** Rotate a vector by this quaternion, returning newly-allocated result. */
+ public Vec3f rotateVector(Vec3f src) {
+ Vec3f tmp = new Vec3f();
+ rotateVector(src, tmp);
+ return tmp;
+ }
+
+ public String toString() {
+ return "(" + q0 + ", " + q1 + ", " + q2 + ", " + q3 + ")";
+ }
+
+ private void setQ(int i, float val) {
+ switch (i) {
+ case 0: q0 = val; break;
+ case 1: q1 = val; break;
+ case 2: q2 = val; break;
+ case 3: q3 = val; break;
+ default: throw new IndexOutOfBoundsException();
+ }
+ }
+}