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diff --git a/src/gleem/NormalCalc.java b/src/gleem/NormalCalc.java
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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;
+
+import gleem.linalg.*;
+
+/** Calculates normals for a set of polygons. */
+
+public class NormalCalc {
+
+  /** Set of normals computed using {@link gleem.NormalCalc}. */
+  public static class NormalInfo {
+    public Vec3f[] normals;
+    public int[]   normalIndices;
+
+    NormalInfo(Vec3f[] normals, int[] normalIndices) {
+      this.normals = normals;
+      this.normalIndices = normalIndices;
+    }
+  }
+
+  /** Returns null upon failure, or a set of Vec3fs and integers
+      which represent faceted (non-averaged) normals, but per-vertex.
+      Performs bounds checking on indices with respect to vertex list.
+      Index list must represent independent triangles; indices are
+      taken in groups of three. If index list doesn't represent
+      triangles or other error occurred then returns null. ccw flag
+      indicates whether triangles are specified counterclockwise when
+      viewed from top or not. */
+
+  public static NormalInfo computeFacetedNormals(Vec3f[] vertices,
+                                                 int[] indices,
+                                                 boolean ccw) {
+    if ((indices.length % 3) != 0) {
+      System.err.println("NormalCalc.computeFacetedNormals: numIndices wasn't " +
+                         "divisible by 3, so it can't possibly " +
+                         "represent a set of triangles");
+      return null;
+    }
+    
+    Vec3f[] outputNormals  = new Vec3f[indices.length / 3];
+    int[] outputNormalIndices = new int[indices.length];
+
+    Vec3f d1 = new Vec3f();
+    Vec3f d2 = new Vec3f();
+    int curNormalIndex = 0;
+    for (int i = 0; i < indices.length; i += 3) {
+      int i0 = indices[i];
+      int i1 = indices[i+1];
+      int i2 = indices[i+2];
+      if ((i0 < 0) || (i0 >= indices.length) ||
+	  (i1 < 0) || (i1 >= indices.length) ||
+	  (i2 < 0) || (i2 >= indices.length)) {
+	  System.err.println("NormalCalc.computeFacetedNormals: ERROR: " +
+                             "vertex index out of bounds or no end of triangle " +
+                             "index found");
+          return null;
+        }
+      Vec3f v0 = vertices[i0];
+      Vec3f v1 = vertices[i1];
+      Vec3f v2 = vertices[i2];
+      d1.sub(v1, v0);
+      d2.sub(v2, v0);
+      Vec3f n = new Vec3f();
+      if (ccw) {
+        n.cross(d1, d2);
+      } else {
+        n.cross(d2, d1);
+      }
+      n.normalize();
+      outputNormals[curNormalIndex] = n;
+      outputNormalIndices[i] = curNormalIndex;
+      outputNormalIndices[i+1] = curNormalIndex;
+      outputNormalIndices[i+2] = curNormalIndex;
+      curNormalIndex++;
+    }
+    return new NormalInfo(outputNormals, outputNormalIndices);
+  }
+}