/*
* Copyright 1999-2008 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
package javax.media.j3d;
import javax.vecmath.Point3d;
import javax.vecmath.Point4d;
/**
* PickCylinderSegment is a finite cylindrical segment pick shape. It can
* be used as an argument to the picking methods in BranchGroup and Locale.
*
* @see BranchGroup#pickAll
* @see Locale#pickAll
*
* @since Java 3D 1.2
*/
public final class PickCylinderSegment extends PickCylinder {
Point3d end;
/**
* Constructs an empty PickCylinderSegment.
* The origin and end points of the cylindrical segment are
* initialized to (0,0,0). The radius is initialized
* to 0.
*/
public PickCylinderSegment() {
this.end = new Point3d();
}
/**
* Constructs a finite cylindrical segment pick shape from the specified
* parameters.
* @param origin the origin point of the cylindrical segment.
* @param end the end point of the cylindrical segment.
* @param radius the radius of the cylindrical segment.
*/
public PickCylinderSegment(Point3d origin, Point3d end, double radius) {
this.origin = new Point3d(origin);
this.end = new Point3d(end);
this.radius = radius;
calcDirection(); // calculate direction, based on start and end
}
/**
* Sets the parameters of this PickCylinderSegment to the specified values.
* @param origin the origin point of the cylindrical segment.
* @param end the end point of the cylindrical segment.
* @param radius the radius of the cylindrical segment.
*/
public void set(Point3d origin, Point3d end, double radius) {
this.origin.set(origin);
this.end.set(end);
this.radius = radius;
calcDirection(); // calculate direction, based on start and end
}
/** Calculates the direction for this PickCylinderSegment, based on start
and end points.
*/
private void calcDirection() {
this.direction.x = end.x - origin.x;
this.direction.y = end.y - origin.y;
this.direction.z = end.z - origin.z;
}
/**
* Gets the end point of this PickCylinderSegment.
* @param end the Point3d object into which the end point
* will be copied.
*/
public void getEnd(Point3d end) {
end.set(this.end);
}
/**
* Returns true if shape intersect with bounds.
* The point of intersection is stored in pickPos.
* @param bounds the bounds object to check
* @param pickPos the location of the point of intersection (not used for
* method. Provided for compatibility).
*/
@Override
final boolean intersect(Bounds bounds, Point4d pickPos) {
Point4d iPnt = new Point4d();
//
// ================ BOUNDING SPHERE ================
//
if (bounds instanceof BoundingSphere) {
Point3d sphCenter = ((BoundingSphere)bounds).getCenter();
double sphRadius = ((BoundingSphere)bounds).getRadius();
double sqDist = Utils.ptToSegSquare(sphCenter, origin, end, null);
if (sqDist <= (sphRadius+radius)*(sphRadius+radius)) {
return true;
}
return false; // we are too far to intersect
}
//
// ================ BOUNDING BOX ================
//
else if (bounds instanceof BoundingBox) {
// Calculate radius of BoundingBox
Point3d lower = new Point3d();
((BoundingBox)bounds).getLower (lower);
Point3d center = ((BoundingBox)bounds).getCenter ();
double temp = (center.x - lower.x + radius);
double boxRadiusSquared = temp*temp;
temp = (center.y - lower.y + radius);
boxRadiusSquared += temp*temp;
temp = (center.z - lower.z + radius);
boxRadiusSquared += temp*temp;
// First, see if cylinder is too far away from BoundingBox
double sqDist = Utils.ptToSegSquare(center, origin, end, null);
if (sqDist > boxRadiusSquared) {
return false; // we are too far to intersect
}
else if (sqDist < (radius*radius)) {
return true; // center is in cylinder
}
// Then, see if ray intersects
if (((BoundingBox)bounds).intersect (origin, end, iPnt)) {
return true;
}
// Ray does not intersect, test for distance with each edge
Point3d upper = new Point3d();
((BoundingBox)bounds).getUpper (upper);
Point3d[][] edges = {
// Top horizontal 4
{upper, new Point3d (lower.x, upper.y, upper.z)},
{new Point3d(lower.x, upper.y, upper.z), new Point3d(lower.x, lower.y, upper.z)},
{new Point3d(lower.x, lower.y, upper.z), new Point3d(upper.x, lower.y, upper.z)},
{new Point3d(upper.x, lower.y, upper.z), upper},
// Bottom horizontal 4
{lower, new Point3d(lower.x, upper.y, lower.z)},
{new Point3d(lower.x, upper.y, lower.z), new Point3d(upper.x, upper.y, lower.z)},
{new Point3d(upper.x, upper.y, lower.z), new Point3d(upper.x, lower.y, lower.z)},
{new Point3d(upper.x, lower.y, lower.z), lower},
// Vertical 4
{lower, new Point3d(lower.x, lower.y, upper.z)},
{new Point3d(lower.x, upper.y, lower.z), new Point3d(lower.x, upper.y, upper.z)},
{new Point3d(upper.x, upper.y, lower.z), new Point3d(upper.x, upper.y, upper.z)},
{new Point3d(upper.x, lower.y, lower.z), new Point3d(upper.x, lower.y, upper.z)}
};
for (int i=0;i<edges.length;i++) {
// System.err.println ("Testing edge: "+edges[i][0]+" - "+edges[i][1]);
double distToEdge =
Utils.segmentToSegment (origin, end,
edges[i][0], edges[i][1], null, null, null);
if (distToEdge <= radius*radius) {
// System.err.println ("Intersects!");
return true;
}
}
return false; // Not close enough
}
//
// ================ BOUNDING POLYTOPE ================
//
else if (bounds instanceof BoundingPolytope) {
int i, j;
// First, check to see if we are too far to intersect the polytope's
// bounding sphere
Point3d sphCenter = new Point3d();
BoundingSphere bsphere = new BoundingSphere (bounds);
bsphere.getCenter (sphCenter);
double sphRadius = bsphere.getRadius();
double sqDist = Utils.ptToSegSquare(sphCenter, origin, end, null);
if (sqDist > (sphRadius+radius)*(sphRadius+radius)) {
return false; // we are too far to intersect
}
// Now check to see if ray intersects with polytope
if (bounds.intersect (origin, direction, iPnt)) {
return true;
}
// Now check distance to edges. Since we don't know a priori how
// the polytope is structured, we will cycle through. We discard edges
// when their center is not on the polytope surface.
BoundingPolytope ptope = (BoundingPolytope)bounds;
Point3d midpt = new Point3d();
double distToEdge;
for (i=0;i<ptope.nVerts;i++) {
for (j=i;i<ptope.nVerts;i++) {
// XXXX: make BoundingPolytope.pointInPolytope available to package
// scope
midpt.x = (ptope.verts[i].x + ptope.verts[j].x) * 0.5;
midpt.y = (ptope.verts[i].y + ptope.verts[j].y) * 0.5;
midpt.z = (ptope.verts[i].z + ptope.verts[j].z) * 0.5;
if (! PickCylinder.pointInPolytope (ptope,
midpt.x, midpt.y, midpt.z)) {
continue;
}
distToEdge =
Utils.segmentToSegment (origin, end,
ptope.verts[i], ptope.verts[j], null, null, null);
if (distToEdge <= radius*radius) {
return true;
}
}
}
return false;
}
/*
else {
throw new RuntimeException("intersect method not implemented");
}
*/
return false;
}
// Only use within J3D.
// Return a new PickCylinderSegment that is the transformed (t3d) of this
// pickCylinderSegment.
@Override
PickShape transform(Transform3D t3d) {
PickCylinderSegment newPCS = new PickCylinderSegment();
newPCS.origin.x = origin.x;
newPCS.origin.y = origin.y;
newPCS.origin.z = origin.z;
newPCS.radius = radius * t3d.getScale();
newPCS.end.x = end.x;
newPCS.end.y = end.y;
newPCS.end.z = end.z;
t3d.transform(newPCS.origin);
t3d.transform(newPCS.end);
newPCS.direction.x = newPCS.end.x - newPCS.origin.x;
newPCS.direction.y = newPCS.end.y - newPCS.origin.y;
newPCS.direction.z = newPCS.end.z - newPCS.origin.z;
newPCS.direction.normalize();
return newPCS;
}
}