protected void splitMesh(
final Mesh mesh, final int sectionStart, final int sectionEnd, final boolean doSort) {
_mesh = makeRef(mesh);
// Split range in half
final int rangeSize = sectionEnd - sectionStart;
final int halfRange = rangeSize / 2; // odd number will give +1 to right.
// left half:
// if half size == 1, create as regular CollisionTree
if (halfRange == 1) {
// compute section
final int section = sectionStart;
// create the left child
_left = new CollisionTree(_type);
_left._primitiveIndices = new int[mesh.getMeshData().getPrimitiveCount(section)];
for (int i = 0; i < _left._primitiveIndices.length; i++) {
_left._primitiveIndices[i] = i;
}
_left._mesh = _mesh;
_left.createTree(section, 0, _left._primitiveIndices.length, doSort);
} else {
// otherwise, make an empty collision tree and call split with new range
_left = new CollisionTree(_type);
_left.splitMesh(mesh, sectionStart, sectionStart + halfRange, doSort);
}
// right half:
// if rangeSize - half size == 1, create as regular CollisionTree
if (rangeSize - halfRange == 1) {
// compute section
final int section = sectionStart + 1;
// create the left child
_right = new CollisionTree(_type);
_right._primitiveIndices = new int[mesh.getMeshData().getPrimitiveCount(section)];
for (int i = 0; i < _right._primitiveIndices.length; i++) {
_right._primitiveIndices[i] = i;
}
_right._mesh = _mesh;
_right.createTree(section, 0, _right._primitiveIndices.length, doSort);
} else {
// otherwise, make an empty collision tree and call split with new range
_right = new CollisionTree(_type);
_right.splitMesh(mesh, sectionStart + halfRange, sectionEnd, doSort);
}
// Ok, now since we technically have no primitives, we need our bounds to be the merging of our
// children bounds
// instead:
_bounds = _left._bounds.clone(_bounds);
_bounds.mergeLocal(_right._bounds);
_worldBounds = _bounds.clone(_worldBounds);
}
/**
* Creates a Collision Tree by recursively creating children nodes, splitting the primitives this
* node is responsible for in half until the desired primitive count is reached.
*
* @param start The start index of the primitivesArray, inclusive.
* @param end The end index of the primitivesArray, exclusive.
* @param doSort True if the primitives should be sorted at each level, false otherwise.
*/
public void createTree(final int section, final int start, final int end, final boolean doSort) {
_section = section;
_start = start;
_end = end;
if (_primitiveIndices == null) {
return;
}
createBounds();
// the bounds at this level should contain all the primitives this level is responsible for.
_bounds.computeFromPrimitives(
getMesh().getMeshData(), _section, _primitiveIndices, _start, _end);
// check to see if we are a leaf, if the number of primitives we reference is less than or equal
// to the maximum
// defined by the CollisionTreeManager we are done.
if (_end - _start + 1 <= CollisionTreeManager.getInstance().getMaxPrimitivesPerLeaf()) {
return;
}
// if doSort is set we need to attempt to optimize the referenced primitives. optimizing the
// sorting of the
// primitives will help group them spatially in the left/right children better.
if (doSort) {
sortPrimitives();
}
// create the left child
if (_left == null) {
_left = new CollisionTree(_type);
}
_left._primitiveIndices = _primitiveIndices;
_left._mesh = _mesh;
_left.createTree(_section, _start, (_start + _end) / 2, doSort);
// create the right child
if (_right == null) {
_right = new CollisionTree(_type);
}
_right._primitiveIndices = _primitiveIndices;
_right._mesh = _mesh;
_right.createTree(_section, (_start + _end) / 2, _end, doSort);
}