Integration of Tomas Hrasky's port of basic GLU NURBS functionality

from C++ to Java, plus example applications, done as part of his
Bachelor of Science degree at the University of Hradec Králové,
Faculty of Informatics and Management.

Current state of code is documented in
src/classes/com/sun/opengl/impl/nurbs/README.txt.

Example applications require Java 1.5 and are not currently built by
default. Specify -Djogl.nurbs=1 during jogl-demos build with a 1.5
javac on the PATH to build them. Dependent jars are copied to build
output directory.

Deleted old partially-complete GLU NURBS port.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@1389 232f8b59-042b-4e1e-8c03-345bb8c30851

1 files changed, 179 insertions, 0 deletions

diff --git a/src/classes/com/sun/opengl/impl/nurbs/Knotvector.java b/src/classes/com/sun/opengl/impl/nurbs/Knotvector.java
new file mode 100755
index 000000000..1442fe17d
--- /dev/null
+++ b/src/classes/com/sun/opengl/impl/nurbs/Knotvector.java
@@ -0,0 +1,179 @@
+package com.sun.opengl.impl.nurbs;
+
+/*
+ ** License Applicability. Except to the extent portions of this file are
+ ** made subject to an alternative license as permitted in the SGI Free
+ ** Software License B, Version 1.1 (the "License"), the contents of this
+ ** file are subject only to the provisions of the License. You may not use
+ ** this file except in compliance with the License. You may obtain a copy
+ ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
+ ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
+ **
+ ** http://oss.sgi.com/projects/FreeB
+ **
+ ** Note that, as provided in the License, the Software is distributed on an
+ ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
+ ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
+ ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
+ ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
+ **
+ ** Original Code. The Original Code is: OpenGL Sample Implementation,
+ ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
+ ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
+ ** Copyright in any portions created by third parties is as indicated
+ ** elsewhere herein. All Rights Reserved.
+ **
+ ** Additional Notice Provisions: The application programming interfaces
+ ** established by SGI in conjunction with the Original Code are The
+ ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
+ ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
+ ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
+ ** Window System(R) (Version 1.3), released October 19, 1998. This software
+ ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
+ ** published by SGI, but has not been independently verified as being
+ ** compliant with the OpenGL(R) version 1.2.1 Specification.
+ */
+
+/**
+ * Knot vector used in curve specification
+ * 
+ * @author Tomas Hrasky
+ * 
+ */
+class Knotvector {
+
+  /**
+   * Tolerance used when comparing knots - when difference is smaller, knots
+   * are considered equal
+   */
+  public static final float TOLERANCE = 1.0e-5f;
+
+  /**
+   * Maximum curve order
+   */
+  private static final int MAXORDER = 24;
+
+  /**
+   * Number of knots
+   */
+  int knotcount;
+
+  /**
+   * Number of control points' coordinates
+   */
+  int stride;
+
+  /**
+   * Curve order
+   */
+  int order;
+
+  /**
+   * Knots
+   */
+  float[] knotlist;
+
+  /**
+   * Makes new knotvector
+   * 
+   * @param nknots
+   *            number of knots
+   * @param stride
+   *            number of ctrl points' corrdinates
+   * @param order
+   *            curve order
+   * @param knot
+   *            knots
+   */
+  public Knotvector(int nknots, int stride, int order, float[] knot) {
+    // DONE
+    init(nknots, stride, order, knot);
+  }
+
+  /**
+   * Initializes knotvector
+   * 
+   * @param nknots
+   *            number of knots
+   * @param stride
+   *            number of ctrl points' corrdinates
+   * @param order
+   *            curve order
+   * @param knot
+   *            knots
+   */
+  public void init(int nknots, int stride, int order, float[] knot) {
+    // DONE
+    this.knotcount = nknots;
+    this.stride = stride;
+    this.order = order;
+    this.knotlist = new float[nknots];
+    for (int i = 0; i < nknots; i++) {
+      this.knotlist[i] = knot[i];
+    }
+
+  }
+
+  /**
+   * Validates knot vector parameters
+   * 
+   * @return knot vector validity
+   */
+  public int validate() {
+    int kindex = knotcount - 1;
+    if (order < 1 || order > MAXORDER) {
+      return 1;
+    }
+    if (knotcount < 2 * order) {
+      return 2;
+    }
+    if (identical(knotlist[kindex - (order - 1)], knotlist[order - 1])) {
+      return 3;
+    }
+    for (int i = 0; i < kindex; i++) {
+      if (knotlist[i] > knotlist[i + 1])
+        return 4;
+    }
+    int multi = 1;
+    for (; kindex >= 1; kindex--) {
+      if (knotlist[kindex] - knotlist[kindex - 1] < TOLERANCE) {
+        multi++;
+        continue;
+      }
+      if (multi > order) {
+        return 5;
+      }
+      multi = 1;
+    }
+    if (multi > order) {
+      return 5;
+    }
+
+    return 0;
+  }
+
+  /**
+   * Show specified message
+   * 
+   * @param msg
+   *            message to be shown
+   */
+  public void show(String msg) {
+    // TODO Auto-generated method stub
+    //			System.out.println("TODO knotvector.show");
+
+  }
+
+  /**
+   * Compares two knots for equality
+   * 
+   * @param a
+   *            first knot
+   * @param b
+   *            second knot
+   * @return knots are/are not equal
+   */
+  public static boolean identical(float a, float b) {
+    return ((a - b) < TOLERANCE) ? true : false;
+  }
+}