/**
* intersect checks for collisions between this collision tree and a provided Ray. Any collisions
* are stored in a provided list as primitive index values. The ray is assumed to have a
* normalized direction for accurate calculations.
*
* @param ray the ray to test for intersections.
* @param store a list to fill with the index values of the primitive hit. if null, a new List is
* created.
* @return the list.
*/
public List<PrimitiveKey> intersect(final Ray3 ray, final List<PrimitiveKey> store) {
List<PrimitiveKey> result = store;
if (result == null) {
result = new ArrayList<PrimitiveKey>();
}
// if our ray doesn't hit the bounds, then it must not hit a primitive.
if (!_worldBounds.intersects(ray)) {
return result;
}
// This is not a leaf node, therefore, check each child (left/right) for intersection with the
// ray.
if (_left != null) {
_left._worldBounds =
_left._bounds.transform(getMesh().getWorldTransform(), _left._worldBounds);
_left.intersect(ray, result);
}
if (_right != null) {
_right._worldBounds =
_right._bounds.transform(getMesh().getWorldTransform(), _right._worldBounds);
_right.intersect(ray, result);
} else if (_left == null) {
// This is a leaf node. We can therefore check each primitive this node contains. If an
// intersection occurs,
// place it in the list.
final MeshData data = getMesh().getMeshData();
final ReadOnlyTransform transform = getMesh().getWorldTransform();
Vector3[] points = null;
for (int i = _start; i < _end; i++) {
points = data.getPrimitiveVertices(_primitiveIndices[i], _section, points);
for (int t = 0; t < points.length; t++) {
transform.applyForward(points[t]);
}
if (ray.intersects(points, null)) {
result.add(new PrimitiveKey(_primitiveIndices[i], _section));
}
}
}
return result;
}
/**
* Determines if this Collision Tree intersects the given CollisionTree. If a collision occurs,
* true is returned, otherwise false is returned. If the provided collisionTree is invalid, false
* is returned. All collisions that occur are stored in lists as an integer index into the mesh's
* triangle buffer. where aList is the primitives for this mesh and bList is the primitives for
* the test tree.
*
* @param collisionTree The Tree to test.
* @param aList a list to contain the colliding primitives of this mesh.
* @param bList a list to contain the colliding primitives of the testing mesh.
* @return True if they intersect, false otherwise.
*/
public boolean intersect(
final CollisionTree collisionTree,
final List<PrimitiveKey> aList,
final List<PrimitiveKey> bList) {
if (collisionTree == null) {
return false;
}
collisionTree._worldBounds =
collisionTree._bounds.transform(
collisionTree.getMesh().getWorldTransform(), collisionTree._worldBounds);
// our two collision bounds do not intersect, therefore, our primitives
// must not intersect. Return false.
if (!intersectsBounding(collisionTree._worldBounds)) {
return false;
}
// if our node is not a leaf send the children (both left and right) to
// the test tree.
if (_left != null) { // This is not a leaf
boolean test = collisionTree.intersect(_left, bList, aList);
test = collisionTree.intersect(_right, bList, aList) || test;
return test;
}
// This node is a leaf, but the testing tree node is not. Therefore,
// continue processing the testing tree until we find its leaves.
if (collisionTree._left != null) {
boolean test = intersect(collisionTree._left, aList, bList);
test = intersect(collisionTree._right, aList, bList) || test;
return test;
}
// both this node and the testing node are leaves. Therefore, we can
// switch to checking the contained primitives with each other. Any
// that are found to intersect are placed in the appropriate list.
final ReadOnlyTransform transformA = getMesh().getWorldTransform();
final ReadOnlyTransform transformB = collisionTree.getMesh().getWorldTransform();
final MeshData dataA = getMesh().getMeshData();
final MeshData dataB = collisionTree.getMesh().getMeshData();
Vector3[] storeA = null;
Vector3[] storeB = null;
boolean test = false;
for (int i = _start; i < _end; i++) {
storeA = dataA.getPrimitiveVertices(_primitiveIndices[i], _section, storeA);
// to world space
for (int t = 0; t < storeA.length; t++) {
transformA.applyForward(storeA[t]);
}
for (int j = collisionTree._start; j < collisionTree._end; j++) {
storeB =
dataB.getPrimitiveVertices(
collisionTree._primitiveIndices[j], collisionTree._section, storeB);
// to world space
for (int t = 0; t < storeB.length; t++) {
transformB.applyForward(storeB[t]);
}
if (Intersection.intersection(storeA, storeB)) {
test = true;
aList.add(new PrimitiveKey(_primitiveIndices[i], _section));
bList.add(new PrimitiveKey(collisionTree._primitiveIndices[j], collisionTree._section));
}
}
}
return test;
}
/**
* Determines if this Collision Tree intersects the given CollisionTree. If a collision occurs,
* true is returned, otherwise false is returned. If the provided collisionTree is invalid, false
* is returned.
*
* @param collisionTree The Tree to test.
* @return True if they intersect, false otherwise.
*/
public boolean intersect(final CollisionTree collisionTree) {
if (collisionTree == null) {
return false;
}
collisionTree._worldBounds =
collisionTree._bounds.transform(
collisionTree.getMesh().getWorldTransform(), collisionTree._worldBounds);
// our two collision bounds do not intersect, therefore, our primitives
// must not intersect. Return false.
if (!intersectsBounding(collisionTree._worldBounds)) {
return false;
}
// check children
if (_left != null) { // This is not a leaf
if (collisionTree.intersect(_left)) {
return true;
}
if (collisionTree.intersect(_right)) {
return true;
}
return false;
}
// This is a leaf
if (collisionTree._left != null) {
// but collision isn't
if (intersect(collisionTree._left)) {
return true;
}
if (intersect(collisionTree._right)) {
return true;
}
return false;
}
// both are leaves
final ReadOnlyTransform transformA = getMesh().getWorldTransform();
final ReadOnlyTransform transformB = collisionTree.getMesh().getWorldTransform();
final MeshData dataA = getMesh().getMeshData();
final MeshData dataB = collisionTree.getMesh().getMeshData();
Vector3[] storeA = null;
Vector3[] storeB = null;
// for every primitive to compare, put them into world space and check for intersections
for (int i = _start; i < _end; i++) {
storeA = dataA.getPrimitiveVertices(_primitiveIndices[i], _section, storeA);
// to world space
for (int t = 0; t < storeA.length; t++) {
transformA.applyForward(storeA[t]);
}
for (int j = collisionTree._start; j < collisionTree._end; j++) {
storeB =
dataB.getPrimitiveVertices(
collisionTree._primitiveIndices[j], collisionTree._section, storeB);
// to world space
for (int t = 0; t < storeB.length; t++) {
transformB.applyForward(storeB[t]);
}
if (Intersection.intersection(storeA, storeB)) {
return true;
}
}
}
return false;
}