1 files changed, 107 insertions, 0 deletions
diff --git a/src/AppearanceMixed/Tetrahedron.java b/src/AppearanceMixed/Tetrahedron.java
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+++ b/src/AppearanceMixed/Tetrahedron.java
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+/*
+ * $RCSfile$
+ *
+ * Copyright (c) 2004 Sun Microsystems, Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistribution of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistribution in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in
+ *   the documentation and/or other materials provided with the
+ *   distribution.
+ *
+ * Neither the name of Sun Microsystems, Inc. or the names of
+ * contributors may 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 OR NON-INFRINGEMENT, ARE HEREBY
+ * EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") AND ITS 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 SUN OR ITS 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 SUN HAS BEEN 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.
+ *
+ * $Revision$
+ * $Date$
+ * $State$
+ */
+
+import javax.media.j3d.*;
+import javax.vecmath.*;
+
+public class Tetrahedron extends Shape3D {
+    private static final float sqrt3 = (float) Math.sqrt(3.0);
+    private static final float sqrt3_3 = sqrt3 / 3.0f;
+    private static final float sqrt24_3 = (float) Math.sqrt(24.0) / 3.0f;
+
+    private static final float ycenter = 0.5f * sqrt24_3;
+    private static final float zcenter = -sqrt3_3;
+
+    private static final Point3f p1 = new Point3f(-1.0f, -ycenter, -zcenter);
+    private static final Point3f p2 = new Point3f(1.0f, -ycenter, -zcenter);
+    private static final Point3f p3 =
+	new Point3f(0.0f, -ycenter, -sqrt3 - zcenter);
+    private static final Point3f p4 =
+	new Point3f(0.0f, sqrt24_3 - ycenter, 0.0f);
+
+    private static final Point3f[] verts = {
+	p1, p2, p4,	// front face
+	p1, p4, p3,	// left, back face
+	p2, p3, p4,	// right, back face
+	p1, p3, p2,	// bottom face
+    };
+
+    private TexCoord2f texCoord[] = {
+        new TexCoord2f(0.0f, 0.0f),
+	new TexCoord2f(1.0f, 0.0f),
+        new TexCoord2f(0.5f, sqrt3 / 2.0f),
+    };
+
+    public Tetrahedron() {
+	int i;
+
+	TriangleArray tetra = new TriangleArray(12, TriangleArray.COORDINATES |
+		TriangleArray.NORMALS | TriangleArray.TEXTURE_COORDINATE_2);
+
+	tetra.setCoordinates(0, verts);
+        for (i = 0; i < 12; i++) {
+            tetra.setTextureCoordinate(0, i, texCoord[i%3]);
+        }
+
+	int face;
+	Vector3f normal = new Vector3f();
+	Vector3f v1 = new Vector3f();
+	Vector3f v2 = new Vector3f();
+	Point3f [] pts = new Point3f[3];
+	for (i = 0; i < 3; i++) pts[i] = new Point3f();
+
+	for (face = 0; face < 4; face++) {
+	    tetra.getCoordinates(face*3, pts);
+	    v1.sub(pts[1], pts[0]);
+	    v2.sub(pts[2], pts[0]);
+	    normal.cross(v1, v2);
+	    normal.normalize();
+	    for (i = 0; i < 3; i++) {
+		tetra.setNormal((face * 3 + i), normal);
+	    }
+	}
+	this.setGeometry(tetra);
+	this.setAppearance(new Appearance());
+    }
+}