ViewProj.java Source code

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Here is the source code for ViewProj.java

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/*
 * %Z%%M% %I% %E% %U%
 * 
 * ************************************************************** "Copyright (c)
 * 2001 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:
 * 
 * -Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
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 * -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.
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 * 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.
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 * 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 AND ITS LICENSORS SHALL NOT BE
 * LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING
 * OR DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR ITS
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 * You acknowledge that Software is not designed,licensed or intended for use in
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import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GraphicsConfiguration;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.BufferedOutputStream;
import java.io.FileOutputStream;
import java.text.NumberFormat;
import java.util.Enumeration;
import java.util.EventListener;
import java.util.EventObject;
import java.util.Hashtable;
import java.util.Vector;

import javax.media.j3d.Alpha;
import javax.media.j3d.Appearance;
import javax.media.j3d.Background;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.ColoringAttributes;
import javax.media.j3d.ImageComponent;
import javax.media.j3d.ImageComponent2D;
import javax.media.j3d.LineArray;
import javax.media.j3d.LineAttributes;
import javax.media.j3d.LineStripArray;
import javax.media.j3d.PolygonAttributes;
import javax.media.j3d.RotationInterpolator;
import javax.media.j3d.Screen3D;
import javax.media.j3d.Shape3D;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.media.j3d.TriangleFanArray;
import javax.media.j3d.View;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.vecmath.AxisAngle4f;
import javax.vecmath.Color3f;
import javax.vecmath.Matrix4d;
import javax.vecmath.Point3d;
import javax.vecmath.Point3f;
import javax.vecmath.Vector3f;
import javax.vecmath.Vector4d;

import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.Sphere;
import com.sun.j3d.utils.universe.SimpleUniverse;
import com.sun.j3d.utils.universe.ViewingPlatform;

public class ViewProj extends Applet implements Java3DExplorerConstants {

    PolygonAttributes solidPa;

    PolygonAttributes wirePa;

    JSlider dynamicOffsetSlider;

    JSlider staticOffsetSlider;

    JLabel dynamicSliderValueLabel;

    JLabel staticSliderValueLabel;

    float dynamicOffset = 1.0f;

    float staticOffset = 1.0f;

    float frontClipDist = 1.413f;

    float backClipDist = 3.309f;

    float backClipRatio = backClipDist / frontClipDist;

    View view;

    ViewingPlatform viewingPlatform;

    float innerScale = 0.94f;

    TransformGroup innerTG;

    Transform3D scale;

    Transform3D projTrans = new Transform3D();

    int numClipGridPts;

    int maxClipGridPts = 180;

    Point3f[] clipGridPtsVW = new Point3f[maxClipGridPts];

    Point3f[] clipGridPtsProj = new Point3f[maxClipGridPts];

    int numCirclePts = 36;

    Point3f[] circlePtsVW = new Point3f[numCirclePts];

    Point3f[] circlePtsProj = new Point3f[numCirclePts];

    Point3f eyePtVW = new Point3f();

    float fov;

    float sphereRadius = 0.85f;

    BranchGroup urScene;

    BranchGroup lrScene;

    SimpleUniverse urUniverse;

    SimpleUniverse lrUniverse;

    boolean isApplication;

    Canvas3D canvas;

    Canvas3D urCanvas;

    Canvas3D lrCanvas;

    OffScreenCanvas3D offScreenCanvas;

    OffScreenCanvas3D urOffScreenCanvas;

    OffScreenCanvas3D lrOffScreenCanvas;

    String snapImageString = "Snap Main";

    String urSnapImageString = "Snap UR";

    String lrSnapImageString = "Snap LR";

    String outFileBase = "vproj";

    int outFileSeq = 0;

    float offScreenScale = 1.0f;

    String urOutFileBase = "vprojur";

    int urOutFileSeq = 0;

    float urOffScreenScale = 1.0f;

    String lrOutFileBase = "vprojlr";

    int lrOutFileSeq = 0;

    float lrOffScreenScale = 1.0f;

    NumberFormat nf;

    Vector4d projPt = new Vector4d();

    public BranchGroup createSceneGraph() {
        // Create the root of the branch graph
        BranchGroup objRoot = new BranchGroup();

        // Create the transform group node and initialize it to the
        // identity. Enable the TRANSFORM_WRITE capability so that
        // our behavior code can modify it at runtime. Add it to the
        // root of the subgraph.
        TransformGroup objTrans = new TransformGroup();
        objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        objRoot.addChild(objTrans);

        // Create a Sphere. We will display this as both wireframe and
        // solid to make a hidden line display
        // wireframe
        Appearance wireApp = new Appearance();
        ColoringAttributes ca = new ColoringAttributes(black, ColoringAttributes.SHADE_FLAT);
        wireApp.setColoringAttributes(ca);
        wirePa = new PolygonAttributes(PolygonAttributes.POLYGON_LINE, PolygonAttributes.CULL_BACK, 0.0f);
        wireApp.setPolygonAttributes(wirePa);
        Sphere outWireSphere = new Sphere(sphereRadius, 0, 10, wireApp);
        objTrans.addChild(outWireSphere);

        // solid
        ColoringAttributes outCa = new ColoringAttributes(red, ColoringAttributes.SHADE_FLAT);
        Appearance outSolid = new Appearance();
        outSolid.setColoringAttributes(outCa);
        solidPa = new PolygonAttributes(PolygonAttributes.POLYGON_FILL, PolygonAttributes.CULL_BACK, 0.0f);
        solidPa.setPolygonOffsetFactor(dynamicOffset);
        solidPa.setPolygonOffset(staticOffset);
        solidPa.setCapability(PolygonAttributes.ALLOW_OFFSET_WRITE);
        outSolid.setPolygonAttributes(solidPa);
        Sphere outSolidSphere = new Sphere(sphereRadius, 0, 10, outSolid);
        objTrans.addChild(outSolidSphere);

        innerTG = new TransformGroup();
        innerTG.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        scale = new Transform3D();
        updateInnerScale();
        objTrans.addChild(innerTG);

        // Create a smaller sphere to go inside. This sphere has a different
        // tesselation and color
        Sphere inWireSphere = new Sphere(sphereRadius, 0, 15, wireApp);
        innerTG.addChild(inWireSphere);

        // inside solid
        ColoringAttributes inCa = new ColoringAttributes(blue, ColoringAttributes.SHADE_FLAT);
        Appearance inSolid = new Appearance();
        inSolid.setColoringAttributes(inCa);
        inSolid.setPolygonAttributes(solidPa);
        Sphere inSolidSphere = new Sphere(sphereRadius, 0, 15, inSolid);
        innerTG.addChild(inSolidSphere);

        // Create a new Behavior object that will perform the desired
        // operation on the specified transform object and add it into
        // the scene graph.
        AxisAngle4f axisAngle = new AxisAngle4f(0.0f, 0.0f, 1.0f, -(float) Math.PI / 2.0f);
        Transform3D yAxis = new Transform3D();
        Alpha rotationAlpha = new Alpha(-1, Alpha.INCREASING_ENABLE, 0, 0, 80000, 0, 0, 0, 0, 0);

        RotationInterpolator rotator = new RotationInterpolator(rotationAlpha, objTrans, yAxis, 0.0f,
                (float) Math.PI * 2.0f);
        BoundingSphere bounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);
        rotator.setSchedulingBounds(bounds);
        //objTrans.addChild(rotator);

        Background bgWhite = new Background(white);
        bgWhite.setApplicationBounds(bounds);
        objTrans.addChild(bgWhite);

        // Have Java 3D perform optimizations on this scene graph.
        objRoot.compile();

        return objRoot;
    }

    void updateInnerScale() {
        scale.set(innerScale);
        innerTG.setTransform(scale);
    }

    public BranchGroup createVWorldViewSG() {
        // Create the root of the branch graph
        BranchGroup objRoot = new BranchGroup();
        objRoot.setCapability(BranchGroup.ALLOW_DETACH);

        // setup a transform group to hold the scaled scene
        TransformGroup objTrans = new TransformGroup();
        objRoot.addChild(objTrans);

        // get the eye point, field of view and clip distances
        float fov = (float) view.getFieldOfView();

        // figure out the angle factors to find points along the edges
        // of the FOV
        // X = fovSpreadX * (Y - eyeVW.y) + eyeVW.x;
        float fovSpreadX = (float) Math.tan(fov / 2);
        // Z = fovSpreadZ * (X - eyeVW.x) + eyeVW.z;
        float fovSpreadZ = 1.0f / fovSpreadX;
        //System.out.println("fovSpreadX = " + fovSpreadX);
        //System.out.println("fovSpreadZ = " + fovSpreadZ);

        Transform3D vpTransform = new Transform3D();
        viewingPlatform.getViewPlatformTransform().getTransform(vpTransform);
        Vector3f vpTranslation = new Vector3f();
        vpTransform.get(vpTranslation);
        eyePtVW.set(vpTranslation);
        eyePtVW.negate();
        // get the eye point in our 2D coord system.
        Point3f eyePt = new Point3f(0.0f, eyePtVW.z, 0.1f);
        float frontClipDist = (float) view.getFrontClipDistance();
        float backClipDist = (float) view.getBackClipDistance();

        // set up the clip plane lines
        Point3f[] cpPoints = new Point3f[5];
        cpPoints[0] = new Point3f(frontClipDist * fovSpreadX, eyePtVW.z + frontClipDist, 0.1f);
        cpPoints[1] = new Point3f(cpPoints[0]);
        cpPoints[1].x *= -1;
        Point3f backLeft = new Point3f(-backClipDist * fovSpreadX, eyePtVW.z + backClipDist, 0.1f);
        cpPoints[2] = backLeft;
        Point3f backRight = new Point3f(backLeft);
        backRight.x *= -1;
        cpPoints[3] = backRight;
        cpPoints[4] = cpPoints[0];
        //for (int i = 0; i < 4; i++) {
        //    System.out.println("cpPoints[" + i + "] = " + cpPoints[i]);
        //}
        int[] cpLength = new int[1];
        cpLength[0] = 5;
        LineStripArray cpLines = new LineStripArray(5, LineArray.COORDINATES, cpLength);
        cpLines.setCoordinates(0, cpPoints);
        Appearance cpApp = new Appearance();
        ColoringAttributes cpCa = new ColoringAttributes(blue, ColoringAttributes.SHADE_FLAT);
        cpApp.setColoringAttributes(cpCa);
        Shape3D cpShape = new Shape3D(cpLines, cpApp);
        objTrans.addChild(cpShape);

        // get the limits of the space
        float minY = eyePt.y;
        float maxY = backLeft.y;
        float minX = backLeft.x;
        float maxX = backRight.x;

        // figure out the X and Y extents and offsets
        float deltaX = maxX - minX;
        float deltaY = maxY - minY;
        float offsetX = -(maxX + minX) / 2.0f;
        float offsetY = -(maxY + minY) / 2.0f;
        float gridSize = Math.max(deltaX, deltaY);

        // scale the grid slightly to give a border around the edge
        gridSize *= 1.1f;

        //System.out.println("offsetX = " + offsetX);
        //System.out.println("offsetY = " + offsetY);

        // Scale the view to fit -1 to 1
        Transform3D trans = new Transform3D();
        trans.set(new Vector3f(offsetX, offsetY, 0.0f), 2.0f / gridSize);
        objTrans.setTransform(trans);

        // figure out a grid step that is a multiple of 10 which keeps the
        // number of steps less than 30.
        float gridStep = 1.0f;
        while ((gridSize / gridStep) > 30.0) {
            gridStep *= 10;
        }
        int gridNumSteps = (int) Math.ceil(gridSize / gridStep) + 1;

        // allocate the grid points array, four points for each step (x and y)
        // with a couple extra points for the extra grid points added
        // below
        int gridNumPoints = 4 * (gridNumSteps + 4);
        Point3f[] gridPts = new Point3f[gridNumPoints];
        for (int i = 0; i < gridNumPoints; i++) {
            gridPts[i] = new Point3f();
        }

        // find the grid limits. Add a step on each side to make sure
        // the grid is larger than the view
        float gridMinY = gridStepFloor(minY, gridStep) - gridStep;
        float gridMaxY = gridStepCeil(maxY, gridStep) + gridStep;
        float gridMinX = gridStepFloor(minX, gridStep) - gridStep;
        float gridMaxX = gridStepCeil(maxX, gridStep) + gridStep;
        //System.out.println("gridMinY = " + gridMinY);
        //System.out.println("gridMaxY = " + gridMaxY);
        //System.out.println("gridMinX = " + gridMinX);
        //System.out.println("gridMaxX = " + gridMaxX);

        // set up the background grid
        Appearance bgApp = new Appearance();
        ColoringAttributes bgCa = new ColoringAttributes();
        bgCa.setColor(grey);
        LineAttributes bgLa = new LineAttributes();
        bgApp.setColoringAttributes(bgCa);

        // clear out the clip grid point list
        numClipGridPts = 0;

        // set up the vertical lines
        int numPts = 0;
        for (float x = gridMinX; x <= gridMaxX; x += gridStep) {
            gridPts[numPts].x = x;
            gridPts[numPts].y = gridMinY;
            gridPts[numPts].z = -0.2f;
            gridPts[numPts + 1].x = x;
            gridPts[numPts + 1].y = gridMaxY;
            gridPts[numPts + 1].z = -0.2f;
            numPts += 2;

            // try to add a line to the clipped grid
            // find the intersection of the clipped line with the FOV sides
            // this is a distance relative to the eye
            float clipZ = fovSpreadZ * Math.abs(x - eyePtVW.x);
            if (clipZ < frontClipDist) { // clip to front clip plane
                clipZ = frontClipDist;
            }
            if (clipZ < backClipDist) { // clip to back clip plane
                // line is not clipped
                clipGridPtsVW[numClipGridPts].x = x;
                clipGridPtsVW[numClipGridPts].y = clipZ + eyePtVW.z;
                clipGridPtsVW[numClipGridPts].z = -0.1f;
                clipGridPtsVW[numClipGridPts + 1].x = x;
                clipGridPtsVW[numClipGridPts + 1].y = backClipDist + eyePtVW.z;
                clipGridPtsVW[numClipGridPts + 1].z = -0.1f;
                numClipGridPts += 2;
            }
        }
        LineArray vertLa = new LineArray(numPts, LineArray.COORDINATES);
        vertLa.setCoordinates(0, gridPts, 0, numPts);
        Shape3D vertShape = new Shape3D(vertLa, bgApp);
        objTrans.addChild(vertShape);

        // set up the horizontal lines
        numPts = 0;
        for (float y = gridMinY; y <= gridMaxY; y += gridStep) {
            gridPts[numPts].x = gridMinX;
            gridPts[numPts].y = y;
            gridPts[numPts++].z = -0.2f;
            gridPts[numPts].x = gridMaxX;
            gridPts[numPts].y = y;
            gridPts[numPts++].z = -0.2f;

            // try to add a line to the clipped grid
            // find the intersection of the clipped line with the FOV sides
            // this is a distance relative to the eye
            float clipDist = (y - eyePtVW.z);
            if ((clipDist > frontClipDist) && (clipDist < backClipDist)) {

                float clipX = fovSpreadX * clipDist;
                clipGridPtsVW[numClipGridPts].x = -clipX;
                clipGridPtsVW[numClipGridPts].y = y;
                clipGridPtsVW[numClipGridPts].z = -0.1f;
                clipGridPtsVW[numClipGridPts + 1].x = clipX;
                clipGridPtsVW[numClipGridPts + 1].y = y;
                clipGridPtsVW[numClipGridPts + 1].z = -0.1f;
                numClipGridPts += 2;
            }
        }
        LineArray horizLa = new LineArray(numPts, LineArray.COORDINATES);
        horizLa.setCoordinates(0, gridPts, 0, numPts);
        Shape3D horizShape = new Shape3D(horizLa, bgApp);
        objTrans.addChild(horizShape);

        // draw the clipped grid.
        if (numClipGridPts > 0) {
            LineArray clipLa = new LineArray(numClipGridPts, LineArray.COORDINATES);
            clipLa.setCoordinates(0, clipGridPtsVW, 0, numClipGridPts);
            Appearance clipGridApp = new Appearance();
            ColoringAttributes clipCa = new ColoringAttributes(black, ColoringAttributes.SHADE_FLAT);
            clipGridApp.setColoringAttributes(clipCa);
            LineAttributes clipGridLa = new LineAttributes();
            Shape3D clipShape = new Shape3D(clipLa, clipGridApp);
            objTrans.addChild(clipShape);
        }

        // set up the coordinate system
        Appearance coordSysApp = new Appearance();
        LineAttributes coordSysLa = new LineAttributes();
        coordSysLa.setLineWidth(3.0f);
        coordSysApp.setLineAttributes(coordSysLa);
        ColoringAttributes coordSysCa = new ColoringAttributes(grey, ColoringAttributes.SHADE_FLAT);
        coordSysApp.setColoringAttributes(coordSysCa);
        Point3f[] coordSysPts = new Point3f[4];
        coordSysPts[0] = new Point3f(gridMinX, 0, -0.5f);
        coordSysPts[1] = new Point3f(gridMaxX, 0, -0.5f);
        coordSysPts[2] = new Point3f(0, gridMinY, -0.5f);
        coordSysPts[3] = new Point3f(0, gridMaxY, -0.5f);
        LineArray coordSysLines = new LineArray(4, LineArray.COORDINATES);
        coordSysLines.setCoordinates(0, coordSysPts);
        Shape3D coordSysShape = new Shape3D(coordSysLines, coordSysApp);
        objTrans.addChild(coordSysShape);

        // set up the circle
        Appearance circleApp = new Appearance();
        ColoringAttributes circleCa = new ColoringAttributes();
        circleCa.setColor(red);
        circleApp.setColoringAttributes(circleCa);
        PolygonAttributes pa = new PolygonAttributes();
        pa.setCullFace(PolygonAttributes.CULL_NONE);
        circleApp.setPolygonAttributes(pa);
        int step = 360 / (numCirclePts - 1);
        for (int deg = 0; deg < 360; deg += step) {
            double angle = Math.toRadians(deg);
            circlePtsVW[deg / 10].x = sphereRadius * (float) Math.sin(angle);
            circlePtsVW[deg / 10].y = sphereRadius * (float) Math.cos(angle);
            circlePtsVW[deg / 10].z = -0.3f;
        }
        circlePtsVW[numCirclePts - 1].set(circlePtsVW[0]);
        int[] lineStripLength = new int[1];
        lineStripLength[0] = numCirclePts;
        //LineStripArray circleLineStrip = new LineStripArray(numCirclePts,
        //        LineArray.COORDINATES, lineStripLength);
        TriangleFanArray circleLineStrip = new TriangleFanArray(numCirclePts, LineArray.COORDINATES,
                lineStripLength);
        circleLineStrip.setCoordinates(0, circlePtsVW);
        Shape3D circleShape = new Shape3D(circleLineStrip, circleApp);
        objTrans.addChild(circleShape);

        return objRoot;
    }

    // return the closest multiple of step less than value
    float gridStepFloor(float value, float step) {
        return (float) (step * (Math.floor(value / step)));
    }

    // return the closest multiple of step greater than value
    float gridStepCeil(float value, float step) {
        return (float) (step * (Math.ceil(value / step)));
    }

    public BranchGroup createProjViewSG() {
        // Create the root of the branch graph
        BranchGroup objRoot = new BranchGroup();
        objRoot.setCapability(BranchGroup.ALLOW_DETACH);

        // setup a transform group to hold the scaled scene
        TransformGroup objTrans = new TransformGroup();
        Transform3D scale = new Transform3D();
        scale.set(0.9);
        objTrans.setTransform(scale);
        objRoot.addChild(objTrans);

        // create the clip limits line
        Point3f[] cpPoints = new Point3f[5];
        cpPoints[0] = new Point3f(-1, -1, 0.1f);
        cpPoints[1] = new Point3f(1, -1, 0.1f);
        cpPoints[2] = new Point3f(1, 1, 0.1f);
        cpPoints[3] = new Point3f(-1, 1, 0.1f);
        cpPoints[4] = cpPoints[0];
        int[] cpLength = new int[1];
        cpLength[0] = 5;
        LineStripArray cpLines = new LineStripArray(5, LineArray.COORDINATES, cpLength);
        cpLines.setCoordinates(0, cpPoints);
        Appearance cpApp = new Appearance();
        ColoringAttributes cpCa = new ColoringAttributes(blue, ColoringAttributes.SHADE_FLAT);
        cpApp.setColoringAttributes(cpCa);
        LineAttributes cpLa = new LineAttributes();
        Shape3D cpShape = new Shape3D(cpLines, cpApp);
        objTrans.addChild(cpShape);

        // transform and render the clip grid points
        updateProjTrans();

        if (numClipGridPts > 0) {
            // transform the clipGridPts
            for (int i = 0; i < numClipGridPts; i++) {
                projectPoint(clipGridPtsVW[i], clipGridPtsProj[i]);
            }

            LineArray clipLn = new LineArray(numClipGridPts, LineArray.COORDINATES);
            clipLn.setCoordinates(0, clipGridPtsProj, 0, numClipGridPts);
            Appearance clipGridApp = new Appearance();
            ColoringAttributes clipCa = new ColoringAttributes(black, ColoringAttributes.SHADE_FLAT);
            clipGridApp.setColoringAttributes(clipCa);
            LineAttributes clipLa = new LineAttributes();
            Shape3D clipShape = new Shape3D(clipLn, clipGridApp);
            objTrans.addChild(clipShape);
        }

        // set up the circle
        Appearance circleApp = new Appearance();
        ColoringAttributes circleCa = new ColoringAttributes();
        circleCa.setColor(red);
        circleApp.setColoringAttributes(circleCa);
        PolygonAttributes pa = new PolygonAttributes();
        pa.setCullFace(PolygonAttributes.CULL_NONE);
        circleApp.setPolygonAttributes(pa);

        // transform the circlePts
        for (int i = 0; i < numCirclePts; i++) {
            projectPoint(circlePtsVW[i], circlePtsProj[i]);
        }

        int[] lineStripLength = new int[1];
        lineStripLength[0] = numCirclePts;
        //LineStripArray circleLineStrip = new LineStripArray(numCirclePts,
        //        LineArray.COORDINATES, lineStripLength);
        TriangleFanArray circleLineStrip = new TriangleFanArray(numCirclePts, LineArray.COORDINATES,
                lineStripLength);
        circleLineStrip.setCoordinates(0, circlePtsProj);
        Shape3D circleShape = new Shape3D(circleLineStrip, circleApp);
        objTrans.addChild(circleShape);

        return objRoot;
    }

    void projectPoint(Point3f ptVW, Point3f ptProj) {
        // handle the VW having y and z switched
        // TODO: fix viewpoint for views
        projPt.x = ptVW.x;
        projPt.y = ptVW.z;
        projPt.z = -ptVW.y;
        projPt.w = 1.0f;

        projPt.z += eyePtVW.z; // TODO: move to projTrans

        //System.out.println("projPtVW = (" +
        //   projPt.x + ", " +
        //   projPt.y + ", " +
        //   projPt.z + ")");

        projTrans.transform(projPt);
        projPt.x /= projPt.w;
        projPt.y /= projPt.w;
        projPt.z /= projPt.w;

        //System.out.println("projPt = (" +
        //   projPt.x + ", " +
        //   projPt.y + ", " +
        //   projPt.z + ")");

        ptProj.x = (float) projPt.x;
        ptProj.y = (float) projPt.z;
        ptProj.z = (float) projPt.y;
    }

    /**
     * Calculates the projection transform specified by the field of view and
     * clip distances specified by the view.
     */
    public void updateProjTrans() {
        int projType = view.getProjectionPolicy();
        if (projType == View.PARALLEL_PROJECTION) {
            //System.out.println("PARALLEL_PROJECTION");
            projTrans.setIdentity();
            return;
        }
        //System.out.println("PERSPECTIVE_PROJECTION");
        // figure out the perspective transform from the view
        double fov = view.getFieldOfView();

        // n = near clip
        double n = frontClipDist;
        // f = far clip
        double f = backClipDist;

        //System.out.println("n = " + nf.format(n) + " f = " + nf.format(f));

        // Create a matrix using coefficents derived from the OpenGL
        // glFrustum() man page. This assumes the eye point is a 0,0,0,
        // the front clip plane is a z = -n, the back clip plane is at
        // z = -f and that the front clip plane intersects the FOV so that
        // -1 <= X,Y <= 1 at the front plane (the last assumption may not
        // be true, so we'll scale later).
        Matrix4d matrix = new Matrix4d();
        matrix.m00 = n;
        matrix.m11 = n;
        matrix.m22 = -(f + n) / (f - n);
        matrix.m23 = -2 * f * n / (f - n);
        matrix.m32 = -1;

        //System.out.println("matrix = " + matrix);

        // This is the distance where the FOV maps to a -1 to 1 area in X and Y
        double d = 1 / Math.tan(fov / 2);

        //System.out.println("n = " + nf.format(n) + " f = " + nf.format(f) +
        //   " d = " + nf.format(d));

        // this is a scaling ratio to make the OpenGL glFrustum() matrix
        // elements work with with the J3D matrix. It compensates for the
        // front clip plane not being at the FOV distance (the OpenGL
        // matrix expects n == d).
        double scale = n / d;
        //System.out.println("scale = " + nf.format(scale));

        // scale the elements of the matrix
        //matrix.m00 *= 1.0/scale;
        //matrix.m11 *= 1.0/scale;
        matrix.m22 *= scale;
        matrix.m23 *= scale;
        matrix.m32 *= scale;

        // set the Transform3D
        projTrans.set(matrix);

        //System.out.println("projTrans = " + projTrans);
    }

    /* TODO: use a behavior post to avoid the flicker when these change */
    void updateViewWindows() {
        BranchGroup newUlScene = createVWorldViewSG();
        urScene.detach();
        urUniverse.addBranchGraph(newUlScene);
        urScene = newUlScene;

        BranchGroup newLlScene = createProjViewSG();
        lrScene.detach();
        lrUniverse.addBranchGraph(newLlScene);
        lrScene = newLlScene;
    }

    public ViewProj() {
        this(true);
    }

    public ViewProj(boolean isApplication) {
        this.isApplication = isApplication;
    }

    public void init() {
        setLayout(new BorderLayout());

        nf = NumberFormat.getInstance();
        nf.setMaximumFractionDigits(3);

        GraphicsConfiguration config = SimpleUniverse.getPreferredConfiguration();

        JPanel canvasPanel = new JPanel();
        GridBagLayout gridbag = new GridBagLayout();
        canvasPanel.setLayout(gridbag);

        canvas = new Canvas3D(config);
        canvas.setSize(400, 400);

        GridBagConstraints constraints = new GridBagConstraints();
        constraints.gridx = 0;
        constraints.gridy = 0;
        constraints.gridwidth = 2;
        constraints.gridheight = 2;
        constraints.insets = new Insets(5, 5, 5, 5);
        constraints.fill = GridBagConstraints.BOTH;
        gridbag.setConstraints(canvas, constraints);
        canvasPanel.add(canvas);

        constraints.fill = GridBagConstraints.REMAINDER;
        constraints.gridwidth = 1;
        constraints.gridheight = 1;
        constraints.gridx = 2;
        constraints.gridy = 0;
        urCanvas = new Canvas3D(config);
        urCanvas.setSize(200, 200);
        gridbag.setConstraints(urCanvas, constraints);
        canvasPanel.add(urCanvas);

        constraints.gridx = 2;
        constraints.gridy = 1;
        lrCanvas = new Canvas3D(config);
        lrCanvas.setSize(200, 200);
        gridbag.setConstraints(lrCanvas, constraints);
        canvasPanel.add(lrCanvas);

        add(canvasPanel, BorderLayout.NORTH);

        SimpleUniverse u = new SimpleUniverse(canvas);
        urUniverse = new SimpleUniverse(urCanvas);
        lrUniverse = new SimpleUniverse(lrCanvas);

        if (isApplication) {
            offScreenCanvas = new OffScreenCanvas3D(config, true);
            // set the size of the off-screen canvas based on a scale
            // of the on-screen size
            Screen3D sOn = canvas.getScreen3D();
            Screen3D sOff = offScreenCanvas.getScreen3D();
            Dimension dim = sOn.getSize();
            dim.width *= offScreenScale;
            dim.height *= offScreenScale;
            sOff.setSize(dim);
            sOff.setPhysicalScreenWidth(sOn.getPhysicalScreenWidth() * offScreenScale);
            sOff.setPhysicalScreenHeight(sOn.getPhysicalScreenHeight() * offScreenScale);

            // attach the offscreen canvas to the view
            u.getViewer().getView().addCanvas3D(offScreenCanvas);

            urOffScreenCanvas = new OffScreenCanvas3D(config, true);
            // set the size of the off-screen canvas based on a scale
            // of the on-screen size
            sOn = urCanvas.getScreen3D();
            sOff = urOffScreenCanvas.getScreen3D();
            dim = sOn.getSize();
            dim.width *= urOffScreenScale;
            dim.height *= urOffScreenScale;
            sOff.setSize(dim);
            sOff.setPhysicalScreenWidth(sOn.getPhysicalScreenWidth() * urOffScreenScale);
            sOff.setPhysicalScreenHeight(sOn.getPhysicalScreenHeight() * urOffScreenScale);

            // attach the offscreen canvas to the view
            urUniverse.getViewer().getView().addCanvas3D(urOffScreenCanvas);

            lrOffScreenCanvas = new OffScreenCanvas3D(config, true);
            // set the size of the off-screen canvas based on a scale
            // of the on-screen size
            sOn = lrCanvas.getScreen3D();
            sOff = lrOffScreenCanvas.getScreen3D();
            dim = sOn.getSize();
            dim.width *= lrOffScreenScale;
            dim.height *= lrOffScreenScale;
            sOff.setSize(dim);
            sOff.setPhysicalScreenWidth(sOn.getPhysicalScreenWidth() * lrOffScreenScale);
            sOff.setPhysicalScreenHeight(sOn.getPhysicalScreenHeight() * lrOffScreenScale);

            // attach the offscreen canvas to the view
            lrUniverse.getViewer().getView().addCanvas3D(lrOffScreenCanvas);
        }

        // Create a simple scene and attach it to the virtual universe
        BranchGroup scene = createSceneGraph();

        // This will move the ViewPlatform back a bit so the
        // objects in the scene can be viewed.
        viewingPlatform = u.getViewingPlatform();
        viewingPlatform.setNominalViewingTransform();

        view = u.getViewer().getView();
        view.setFrontClipPolicy(View.VIRTUAL_EYE);
        view.setBackClipPolicy(View.VIRTUAL_EYE);
        view.setFrontClipDistance(frontClipDist);
        view.setBackClipDistance(backClipDist);

        u.addBranchGraph(scene);

        // init the clipGridPts arrays
        for (int i = 0; i < maxClipGridPts; i++) {
            clipGridPtsVW[i] = new Point3f();
            clipGridPtsProj[i] = new Point3f();
        }

        // init the circlePts arrays
        for (int i = 0; i < numCirclePts; i++) {
            circlePtsVW[i] = new Point3f();
            circlePtsProj[i] = new Point3f();
        }

        // setup the ur canvas
        urScene = createVWorldViewSG();
        // This will move the ViewPlatform back a bit so the
        // objects in the scene can be viewed.
        urUniverse.getViewingPlatform().setNominalViewingTransform();
        View urView = urUniverse.getViewer().getView();
        urView.setProjectionPolicy(View.PARALLEL_PROJECTION);
        urUniverse.addBranchGraph(urScene);
        // set up the background on a separate BG so that it can stay there
        // when we replace the scene SG
        Background urBgWhite = new Background(white);
        urBgWhite.setApplicationBounds(infiniteBounds);
        BranchGroup urBackBG = new BranchGroup();
        urBackBG.addChild(urBgWhite);
        urUniverse.addBranchGraph(urBackBG);

        // setup the lr canvas
        lrScene = createProjViewSG();
        // This will move the ViewPlatform back a bit so the
        // objects in the scene can be viewed.
        lrUniverse.getViewingPlatform().setNominalViewingTransform();
        View lrView = lrUniverse.getViewer().getView();
        lrView.setProjectionPolicy(View.PARALLEL_PROJECTION);
        lrUniverse.addBranchGraph(lrScene);
        // set up the background on a separate BG so that it can stay there
        // when we replace the scene SG
        Background lrBgWhite = new Background(white);
        lrBgWhite.setApplicationBounds(infiniteBounds);
        BranchGroup lrBackBG = new BranchGroup();
        lrBackBG.addChild(lrBgWhite);
        lrUniverse.addBranchGraph(lrBackBG);

        // set up the sliders
        JPanel guiPanel = new JPanel();
        guiPanel.setLayout(new GridLayout(0, 2));
        FloatLabelJSlider dynamicSlider = new FloatLabelJSlider("Dynamic Offset", 0.1f, 0.0f, 2.0f, dynamicOffset);
        dynamicSlider.addFloatListener(new FloatListener() {
            public void floatChanged(FloatEvent e) {
                dynamicOffset = e.getValue();
                solidPa.setPolygonOffsetFactor(dynamicOffset);
            }
        });
        guiPanel.add(dynamicSlider);

        LogFloatLabelJSlider staticSlider = new LogFloatLabelJSlider("Static Offset", 0.1f, 10000.0f, staticOffset);
        staticSlider.addFloatListener(new FloatListener() {
            public void floatChanged(FloatEvent e) {
                staticOffset = e.getValue();
                solidPa.setPolygonOffset(staticOffset);
            }
        });
        guiPanel.add(staticSlider);

        // These are declared final here so they can be changed by the
        // listener routines below.
        LogFloatLabelJSlider frontClipSlider = new LogFloatLabelJSlider("Front Clip Distance", 0.001f, 10.0f,
                frontClipDist);
        final LogFloatLabelJSlider backClipSlider = new LogFloatLabelJSlider("Back Clip Distance", 1.0f, 10000.0f,
                backClipDist);
        final LogFloatLabelJSlider backClipRatioSlider = new LogFloatLabelJSlider("Back Clip Ratio", 1.0f, 10000.0f,
                backClipRatio);

        frontClipSlider.addFloatListener(new FloatListener() {
            public void floatChanged(FloatEvent e) {
                frontClipDist = e.getValue();
                view.setFrontClipDistance(frontClipDist);
                backClipRatio = backClipDist / frontClipDist;
                backClipRatioSlider.setValue(backClipRatio);
                updateViewWindows();
            }
        });
        guiPanel.add(frontClipSlider);

        backClipSlider.addFloatListener(new FloatListener() {
            public void floatChanged(FloatEvent e) {
                backClipDist = e.getValue();
                backClipRatio = backClipDist / frontClipDist;
                backClipRatioSlider.setValue(backClipRatio);
                view.setBackClipDistance(backClipDist);
                updateViewWindows();
            }
        });
        guiPanel.add(backClipSlider);

        backClipRatioSlider.addFloatListener(new FloatListener() {
            public void floatChanged(FloatEvent e) {
                backClipRatio = e.getValue();
                backClipDist = backClipRatio * frontClipDist;
                backClipSlider.setValue(backClipDist);
                updateViewWindows();
            }
        });
        guiPanel.add(backClipRatioSlider);
        FloatLabelJSlider innerSphereSlider = new FloatLabelJSlider("Inner Sphere Scale", 0.001f, 0.90f, 1.0f,
                innerScale);
        innerSphereSlider.addFloatListener(new FloatListener() {
            public void floatChanged(FloatEvent e) {
                innerScale = e.getValue();
                updateInnerScale();
            }
        });
        guiPanel.add(innerSphereSlider);

        JButton mainSnap = new JButton(snapImageString);
        mainSnap.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                Point loc = canvas.getLocationOnScreen();
                offScreenCanvas.setOffScreenLocation(loc);
                Dimension dim = canvas.getSize();
                dim.width *= offScreenScale;
                dim.height *= offScreenScale;
                nf.setMinimumIntegerDigits(3);
                offScreenCanvas.snapImageFile(outFileBase + nf.format(outFileSeq++), dim.width, dim.height);
                nf.setMinimumIntegerDigits(0);
            }
        });
        guiPanel.add(mainSnap);

        JButton urSnap = new JButton(urSnapImageString);
        urSnap.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.out.println("Snap UR");
                Point loc = urCanvas.getLocationOnScreen();
                urOffScreenCanvas.setOffScreenLocation(loc);
                Dimension dim = urCanvas.getSize();
                dim.width *= urOffScreenScale;
                dim.height *= urOffScreenScale;
                nf.setMinimumIntegerDigits(3);
                urOffScreenCanvas.snapImageFile(urOutFileBase + nf.format(urOutFileSeq++), dim.width, dim.height);
                nf.setMinimumIntegerDigits(0);
            }
        });
        guiPanel.add(urSnap);

        JButton lrSnap = new JButton(lrSnapImageString);
        lrSnap.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.out.println("Snap LR");
                Point loc = lrCanvas.getLocationOnScreen();
                lrOffScreenCanvas.setOffScreenLocation(loc);
                Dimension dim = lrCanvas.getSize();
                dim.width *= lrOffScreenScale;
                dim.height *= lrOffScreenScale;
                nf.setMinimumIntegerDigits(3);
                lrOffScreenCanvas.snapImageFile(lrOutFileBase + nf.format(lrOutFileSeq++), dim.width, dim.height);
                nf.setMinimumIntegerDigits(0);
            }
        });
        guiPanel.add(lrSnap);
        add(guiPanel, BorderLayout.SOUTH);
    }

    //
    // The following allows ViewProj to be run as an application
    // as well as an applet
    //
    public static void main(String[] args) {
        new MainFrame(new ViewProj(true), 700, 600);
    }
}

interface Java3DExplorerConstants {

    // colors
    static Color3f black = new Color3f(0.0f, 0.0f, 0.0f);

    static Color3f red = new Color3f(1.0f, 0.0f, 0.0f);

    static Color3f green = new Color3f(0.0f, 1.0f, 0.0f);

    static Color3f blue = new Color3f(0.0f, 0.0f, 1.0f);

    static Color3f skyBlue = new Color3f(0.6f, 0.7f, 0.9f);

    static Color3f cyan = new Color3f(0.0f, 1.0f, 1.0f);

    static Color3f magenta = new Color3f(1.0f, 0.0f, 1.0f);

    static Color3f yellow = new Color3f(1.0f, 1.0f, 0.0f);

    static Color3f brightWhite = new Color3f(1.0f, 1.5f, 1.5f);

    static Color3f white = new Color3f(1.0f, 1.0f, 1.0f);

    static Color3f darkGrey = new Color3f(0.15f, 0.15f, 0.15f);

    static Color3f medGrey = new Color3f(0.3f, 0.3f, 0.3f);

    static Color3f grey = new Color3f(0.5f, 0.5f, 0.5f);

    static Color3f lightGrey = new Color3f(0.75f, 0.75f, 0.75f);

    // infinite bounding region, used to make env nodes active everywhere
    BoundingSphere infiniteBounds = new BoundingSphere(new Point3d(), Double.MAX_VALUE);

    // common values
    static final String nicestString = "NICEST";

    static final String fastestString = "FASTEST";

    static final String antiAliasString = "Anti-Aliasing";

    static final String noneString = "NONE";

    // light type constants
    static int LIGHT_AMBIENT = 1;

    static int LIGHT_DIRECTIONAL = 2;

    static int LIGHT_POSITIONAL = 3;

    static int LIGHT_SPOT = 4;

    // screen capture constants
    static final int USE_COLOR = 1;

    static final int USE_BLACK_AND_WHITE = 2;

    // number formatter
    NumberFormat nf = NumberFormat.getInstance();

}

class OffScreenCanvas3D extends Canvas3D {

    OffScreenCanvas3D(GraphicsConfiguration graphicsConfiguration, boolean offScreen) {

        super(graphicsConfiguration, offScreen);
    }

    private BufferedImage doRender(int width, int height) {

        BufferedImage bImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

        ImageComponent2D buffer = new ImageComponent2D(ImageComponent.FORMAT_RGB, bImage);
        //buffer.setYUp(true);

        setOffScreenBuffer(buffer);
        renderOffScreenBuffer();
        waitForOffScreenRendering();
        bImage = getOffScreenBuffer().getImage();
        return bImage;
    }

    void snapImageFile(String filename, int width, int height) {
        BufferedImage bImage = doRender(width, height);

        /*
         * JAI: RenderedImage fImage = JAI.create("format", bImage,
         * DataBuffer.TYPE_BYTE); JAI.create("filestore", fImage, filename +
         * ".tif", "tiff", null);
         */

        /* No JAI: */
        try {
            FileOutputStream fos = new FileOutputStream(filename + ".jpg");
            BufferedOutputStream bos = new BufferedOutputStream(fos);

            JPEGImageEncoder jie = JPEGCodec.createJPEGEncoder(bos);
            JPEGEncodeParam param = jie.getDefaultJPEGEncodeParam(bImage);
            param.setQuality(1.0f, true);
            jie.setJPEGEncodeParam(param);
            jie.encode(bImage);

            bos.flush();
            fos.close();
        } catch (Exception e) {
            System.out.println(e);
        }
    }
}

class FloatLabelJSlider extends JPanel implements ChangeListener, Java3DExplorerConstants {

    JSlider slider;

    JLabel valueLabel;

    Vector listeners = new Vector();

    float min, max, resolution, current, scale;

    int minInt, maxInt, curInt;;

    int intDigits, fractDigits;

    float minResolution = 0.001f;

    // default slider with name, resolution = 0.1, min = 0.0, max = 1.0 inital
    // 0.5
    FloatLabelJSlider(String name) {
        this(name, 0.1f, 0.0f, 1.0f, 0.5f);
    }

    FloatLabelJSlider(String name, float resolution, float min, float max, float current) {

        this.resolution = resolution;
        this.min = min;
        this.max = max;
        this.current = current;

        if (resolution < minResolution) {
            resolution = minResolution;
        }

        // round scale to nearest integer fraction. i.e. 0.3 => 1/3 = 0.33
        scale = (float) Math.round(1.0f / resolution);
        resolution = 1.0f / scale;

        // get the integer versions of max, min, current
        minInt = Math.round(min * scale);
        maxInt = Math.round(max * scale);
        curInt = Math.round(current * scale);

        // sliders use integers, so scale our floating point value by "scale"
        // to make each slider "notch" be "resolution". We will scale the
        // value down by "scale" when we get the event.
        slider = new JSlider(JSlider.HORIZONTAL, minInt, maxInt, curInt);
        slider.addChangeListener(this);

        valueLabel = new JLabel(" ");

        // set the initial value label
        setLabelString();

        // add min and max labels to the slider
        Hashtable labelTable = new Hashtable();
        labelTable.put(new Integer(minInt), new JLabel(nf.format(min)));
        labelTable.put(new Integer(maxInt), new JLabel(nf.format(max)));
        slider.setLabelTable(labelTable);
        slider.setPaintLabels(true);

        /* layout to align left */
        setLayout(new BorderLayout());
        Box box = new Box(BoxLayout.X_AXIS);
        add(box, BorderLayout.WEST);

        box.add(new JLabel(name));
        box.add(slider);
        box.add(valueLabel);
    }

    public void setMinorTickSpacing(float spacing) {
        int intSpacing = Math.round(spacing * scale);
        slider.setMinorTickSpacing(intSpacing);
    }

    public void setMajorTickSpacing(float spacing) {
        int intSpacing = Math.round(spacing * scale);
        slider.setMajorTickSpacing(intSpacing);
    }

    public void setPaintTicks(boolean paint) {
        slider.setPaintTicks(paint);
    }

    public void addFloatListener(FloatListener listener) {
        listeners.add(listener);
    }

    public void removeFloatListener(FloatListener listener) {
        listeners.remove(listener);
    }

    public void stateChanged(ChangeEvent e) {
        JSlider source = (JSlider) e.getSource();
        // get the event type, set the corresponding value.
        // Sliders use integers, handle floating point values by scaling the
        // values by "scale" to allow settings at "resolution" intervals.
        // Divide by "scale" to get back to the real value.
        curInt = source.getValue();
        current = curInt / scale;

        valueChanged();
    }

    public void setValue(float newValue) {
        boolean changed = (newValue != current);
        current = newValue;
        if (changed) {
            valueChanged();
        }
    }

    private void valueChanged() {
        // update the label
        setLabelString();

        // notify the listeners
        FloatEvent event = new FloatEvent(this, current);
        for (Enumeration e = listeners.elements(); e.hasMoreElements();) {
            FloatListener listener = (FloatListener) e.nextElement();
            listener.floatChanged(event);
        }
    }

    void setLabelString() {
        // Need to muck around to try to make sure that the width of the label
        // is wide enough for the largest value. Pad the string
        // be large enough to hold the largest value.
        int pad = 5; // fudge to make up for variable width fonts
        float maxVal = Math.max(Math.abs(min), Math.abs(max));
        intDigits = Math.round((float) (Math.log(maxVal) / Math.log(10))) + pad;
        if (min < 0) {
            intDigits++; // add one for the '-'
        }
        // fractDigits is num digits of resolution for fraction. Use base 10 log
        // of scale, rounded up, + 2.
        fractDigits = (int) Math.ceil((Math.log(scale) / Math.log(10)));
        nf.setMinimumFractionDigits(fractDigits);
        nf.setMaximumFractionDigits(fractDigits);
        String value = nf.format(current);
        while (value.length() < (intDigits + fractDigits)) {
            value = value + "  ";
        }
        valueLabel.setText(value);
    }

}

class FloatEvent extends EventObject {

    float value;

    FloatEvent(Object source, float newValue) {
        super(source);
        value = newValue;
    }

    float getValue() {
        return value;
    }
}

interface FloatListener extends EventListener {
    void floatChanged(FloatEvent e);
}

class LogFloatLabelJSlider extends JPanel implements ChangeListener, Java3DExplorerConstants {

    JSlider slider;

    JLabel valueLabel;

    Vector listeners = new Vector();

    float min, max, resolution, current, scale;

    double minLog, maxLog, curLog;

    int minInt, maxInt, curInt;;

    int intDigits, fractDigits;

    NumberFormat nf = NumberFormat.getInstance();

    float minResolution = 0.001f;

    double logBase = Math.log(10);

    // default slider with name, resolution = 0.1, min = 0.0, max = 1.0 inital
    // 0.5
    LogFloatLabelJSlider(String name) {
        this(name, 0.1f, 100.0f, 10.0f);
    }

    LogFloatLabelJSlider(String name, float min, float max, float current) {

        this.resolution = resolution;
        this.min = min;
        this.max = max;
        this.current = current;

        if (resolution < minResolution) {
            resolution = minResolution;
        }

        minLog = log10(min);
        maxLog = log10(max);
        curLog = log10(current);

        // resolution is 100 steps from min to max
        scale = 100.0f;
        resolution = 1.0f / scale;

        // get the integer versions of max, min, current
        minInt = (int) Math.round(minLog * scale);
        maxInt = (int) Math.round(maxLog * scale);
        curInt = (int) Math.round(curLog * scale);

        slider = new JSlider(JSlider.HORIZONTAL, minInt, maxInt, curInt);
        slider.addChangeListener(this);

        valueLabel = new JLabel(" ");

        // Need to muck around to make sure that the width of the label
        // is wide enough for the largest value. Pad the initial string
        // be large enough to hold the largest value.
        int pad = 5; // fudge to make up for variable width fonts
        intDigits = (int) Math.ceil(maxLog) + pad;
        if (min < 0) {
            intDigits++; // add one for the '-'
        }
        if (minLog < 0) {
            fractDigits = (int) Math.ceil(-minLog);
        } else {
            fractDigits = 0;
        }
        nf.setMinimumFractionDigits(fractDigits);
        nf.setMaximumFractionDigits(fractDigits);
        String value = nf.format(current);
        while (value.length() < (intDigits + fractDigits)) {
            value = value + " ";
        }
        valueLabel.setText(value);

        // add min and max labels to the slider
        Hashtable labelTable = new Hashtable();
        labelTable.put(new Integer(minInt), new JLabel(nf.format(min)));
        labelTable.put(new Integer(maxInt), new JLabel(nf.format(max)));
        slider.setLabelTable(labelTable);
        slider.setPaintLabels(true);

        // layout to align left
        setLayout(new BorderLayout());
        Box box = new Box(BoxLayout.X_AXIS);
        add(box, BorderLayout.WEST);

        box.add(new JLabel(name));
        box.add(slider);
        box.add(valueLabel);
    }

    public void setMinorTickSpacing(float spacing) {
        int intSpacing = Math.round(spacing * scale);
        slider.setMinorTickSpacing(intSpacing);
    }

    public void setMajorTickSpacing(float spacing) {
        int intSpacing = Math.round(spacing * scale);
        slider.setMajorTickSpacing(intSpacing);
    }

    public void setPaintTicks(boolean paint) {
        slider.setPaintTicks(paint);
    }

    public void addFloatListener(FloatListener listener) {
        listeners.add(listener);
    }

    public void removeFloatListener(FloatListener listener) {
        listeners.remove(listener);
    }

    public void stateChanged(ChangeEvent e) {
        JSlider source = (JSlider) e.getSource();
        curInt = source.getValue();
        curLog = curInt / scale;
        current = (float) exp10(curLog);

        valueChanged();
    }

    public void setValue(float newValue) {
        boolean changed = (newValue != current);
        current = newValue;
        if (changed) {
            valueChanged();
        }
    }

    private void valueChanged() {
        String value = nf.format(current);
        valueLabel.setText(value);

        // notify the listeners
        FloatEvent event = new FloatEvent(this, current);
        for (Enumeration e = listeners.elements(); e.hasMoreElements();) {
            FloatListener listener = (FloatListener) e.nextElement();
            listener.floatChanged(event);
        }
    }

    double log10(double value) {
        return Math.log(value) / logBase;
    }

    double exp10(double value) {
        return Math.exp(value * logBase);
    }

}