/* Java3DModel.java Representation of a 3D model as a wire frame of line
segments tailored for use in a Java3D environment.
History:
12 Jun 2008 Delete construction from InputStream.
10 Jun 2008 Adapted from JModel3D.java.
To do:
Use standard constructs for managing LineSegment and Point3f lists.
*/
import java.io.*;
import javax.vecmath.*;
/**
The representation of a 3D model as a wire frame of line segments.
*/
public class Java3DModel extends Model3D {
/**
Radius of the figure's bounding sphere.
*/
public double m_radius = 1.0;
/**
Center of the figure's bounding sphere.
*/
public Point3d m_center = new Point3d();
/**
Origin for computations.
*/
public static final Point3d m_origin = new Point3d();
/**
Minimum size for point and line segment arrays.
*/
public static final int M_MIN_BUFFSIZE = 50;
/**
Coordinates for all points.
*/
public Point3d m_points[];
/**
Size of used portion of vertex arrays.
*/
public int m_npoints;
/**
Class for storing LineSegment data.
*/
public class LineSegment {
public final int m_p1, m_p2; // end points (indices into m_points)
public final int m_type;
LineSegment(int p1, int p2, int type)
{
m_p1 = p1;
m_p2 = p2;
m_type = type;
}
/**
Get first end point.
*/
Point3d p1() { return m_points[m_p1]; }
/**
Get second end point.
*/
Point3d p2() { return m_points[m_p2]; }
}
public LineSegment m_lineSegments[];
public int m_nlineSegments;
public Java3DModel() { }
/**
Zero vertex and lineSegment counts.
*/
public void reset()
{
m_npoints = 0;
m_nlineSegments = 0;
m_center.set(m_origin);
m_radius = 1.0;
}
/**
Add a point to the model's geometry.
@param x x coordinate of point
@param y y coordinate of point
@param z z coordinate of point
*/
void addPoint(double x, double y, double z) {
Point3d point = new Point3d(x, y, z);
if (m_points == null) m_points = new Point3d[M_MIN_BUFFSIZE];
else if (m_npoints >= m_points.length) {
Point3d points[] = new Point3d[m_points.length*2];
System.arraycopy(m_points, 0, points, 0, m_points.length);
m_points = points;
}
m_points[m_npoints++] = point;
}
/**
Add a LineSegment with endpoints p1 and p2 to the model's geometry.
@param p1 zero-based index of first endpoint
@param p2 zero-based index of second endpoint
@param type type value for this line segment
*/
void addLineSegment(int p1, int p2, int type) {
LineSegment lineSegment = new LineSegment(p1, p2, type);
if (lineSegment.m_p1 >= m_npoints || lineSegment.m_p2 >= m_npoints) return;
if (m_lineSegments == null)
m_lineSegments = new LineSegment[M_MIN_BUFFSIZE];
else if (m_nlineSegments >= m_lineSegments.length) {
LineSegment lineSegments[] = new LineSegment[m_lineSegments.length*2];
System.arraycopy(m_lineSegments, 0, lineSegments,
0, m_lineSegments.length);
m_lineSegments = lineSegments;
}
m_lineSegments[m_nlineSegments++] = lineSegment;
}
void computeBoundingSphere() {
// find model center and bounding radius
Vector3d vec = new Vector3d();
for (int i = 0; i < m_npoints; i++) m_center.add(m_points[i]);
m_center.scale(1.0f/m_npoints);
m_radius = 0.0;
for (int i = 0; i < m_npoints; i++) {
vec.sub(m_points[i], m_center);
double length = vec.length();
if (length > m_radius) m_radius = length;
}
}
}