public SpinningTopSpaceView(SpinningTop rigidBody) {
this.rigidBody = rigidBody;
frame.setSize(600, 600);
// panel.setDisplayMode(VisualizationHints.DISPLAY_NO_PERSPECTIVE);
double d = 4;
frame.setPreferredMinMax(-d, d, -d, d, -d, d);
frame.setDecorationType(
org.opensourcephysics.display3d.core.VisualizationHints.DECORATION_AXES);
orientation.getStyle().setFillColor(java.awt.Color.RED);
orientationTrace.getStyle().setLineColor(java.awt.Color.BLACK);
base.setSizeXYZ(2, 2, 0.15);
base.getStyle().setResolution(new Resolution(4, 12, 1));
base.getStyle().setFillColor(java.awt.Color.RED);
base.setZ(-3);
post.setSizeXYZ(0.2, 0.2, 3);
post.getStyle().setResolution(new Resolution(2, 10, 15));
post.setZ(-1.5); // shift by half the length
post.getStyle().setFillColor(java.awt.Color.RED);
shaft.setSizeXYZ(0.2, 0.2, 3);
shaft.setXYZ(0, 0, 1.5);
shaft.getStyle().setResolution(new Resolution(1, 10, 15));
disk.setSizeXYZ(1.75, 1.75, 0.25);
disk.setXYZ(0, 0, 2.0);
disk.getStyle().setResolution(new Resolution(4, 12, 1));
topGroup.addElement(shaft);
topGroup.addElement(disk);
topGroup.setTransformation(rigidBody.getTransformation());
frame.addElement(base);
frame.addElement(post);
frame.addElement(orientation);
frame.addElement(orientationTrace);
frame.addElement(topGroup);
}
void update() {
Transformation transformation = rigidBody.getTransformation();
topGroup.setTransformation(transformation);
double s = 1.5 * shaft.getSizeZ();
double[] vec = topGroup.toSpaceFrame(new double[] {0, 0, 1});
orientation.setSizeXYZ(s * vec[0], s * vec[1], s * vec[2]);
orientationTrace.addPoint(s * vec[0], s * vec[1], s * vec[2]);
frame.render();
}
void initialize() {
double dx = 1 / Math.sqrt(rigidBody.I1); // dimension of ellipsoid is inverse to inertia
double dy = 1 / Math.sqrt(rigidBody.I2);
double dz = 1 / Math.sqrt(rigidBody.I3);
double scale = Math.max(Math.max(4 * dx, 4 * dy), 4 * dz); // bounding dimension
frame.setPreferredMinMax(-scale, scale, -scale, scale, -scale, scale);
orientationTrace.clear();
update();
}