+
+/*******************************************************************************
+
+ Copyright (c) 2009, Charles McGarvey
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice,
+ this list of conditions and the following disclaimer in the documentation
+ and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*******************************************************************************/
+
+#include "Camera.hh"
+#include "Octree.hh"
+
+
+namespace Mf {
+
+
+void Octree::sort()
+{
+ stlplus::ntree<OctreeNode>::prefix_iterator it;
+
+ for (it = tree_.prefix_begin(); it != tree_.prefix_end(); ++it)
+ {
+ it->sort();
+ }
+}
+
+
+stlplus::ntree<OctreeNode>::iterator Octree::insert(stlplus::ntree<OctreeNode>::iterator node,
+ EntityPtr entity)
+{
+ Plane::Halfspace halfspace;
+ int octantNum = -1;
+
+ if (!node.valid())
+ {
+ std::cerr << "cannot insert into invalid node" << std::endl;
+ return stlplus::ntree<OctreeNode>::iterator();
+ }
+
+ Plane xy = node->getAabb().getPlaneXY();
+ halfspace = xy.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = xy.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ Plane xz = node->getAabb().getPlaneXZ();
+ halfspace = xz.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = xz.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ Plane yz = node->getAabb().getPlaneYZ();
+ halfspace = yz.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = yz.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ octantNum = 2;
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ octantNum = 3;
+ }
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ Plane yz = node->getAabb().getPlaneYZ();
+ halfspace = yz.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = yz.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ octantNum = 1;
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ octantNum = 0;
+ }
+ }
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ Plane xz = node->getAabb().getPlaneXZ();
+ halfspace = xz.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = xz.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ Plane yz = node->getAabb().getPlaneYZ();
+ halfspace = yz.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = yz.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ octantNum = 6;
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ octantNum = 7;
+ }
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ Plane yz = node->getAabb().getPlaneYZ();
+ halfspace = yz.intersectsSphere(entity->getSphere());
+ if (halfspace == Plane::INTERSECT)
+ {
+ halfspace = yz.intersectsAabb(entity->getAabb());
+ }
+
+ if (halfspace == Plane::POSITIVE)
+ {
+ octantNum = 5;
+ }
+ else if (halfspace == Plane::NEGATIVE)
+ {
+ octantNum = 4;
+ }
+ }
+ }
+
+ if (octantNum == -1)
+ {
+ node->objects.push_front(entity);
+ return node;
+ }
+ else
+ {
+ if ((int)tree_.children(node) <= octantNum)
+ {
+ addChild(node, octantNum);
+ }
+
+ stlplus::ntree<OctreeNode>::iterator child = tree_.child(node, octantNum);
+
+ if (child.valid())
+ {
+ return insert(child, entity);
+ }
+ else
+ {
+ std::cerr << "expected but found no child at index " << octantNum << std::endl;
+ return stlplus::ntree<OctreeNode>::iterator();
+ }
+ }
+}
+
+stlplus::ntree<OctreeNode>::iterator Octree::reinsert(EntityPtr entity,
+ stlplus::ntree<OctreeNode>::iterator node)
+{
+ if (!node.valid())
+ {
+ std::cerr << "cannot move entity from invalid node" << std::endl;
+ return stlplus::ntree<OctreeNode>::iterator();
+ }
+
+ std::list<EntityPtr>::iterator it;
+ it = std::find(node->objects.begin(), node->objects.end(), entity);
+
+ if (it != node->objects.end())
+ {
+ node->objects.erase(it);
+ }
+
+ return insert(entity);
+}
+
+
+void Octree::addChild(stlplus::ntree<OctreeNode>::iterator node, int index)
+{
+ Aabb octant;
+
+ if (!node.valid())
+ {
+ std::cerr << "cannot add children to invalid node" << std::endl;
+ return;
+ }
+
+ for (int i = tree_.children(node); i <= index; ++i)
+ {
+ node->getAabb().getOctant(octant, i);
+ tree_.append(node, octant);
+ }
+}
+
+
+void Octree::draw(stlplus::ntree<OctreeNode>::iterator node, Scalar alpha)
+{
+ if (!node.valid())
+ {
+ std::cerr << "cannot draw null child node :-(" << std::endl;
+ return;
+ }
+
+ node->draw(alpha);
+
+ for (unsigned i = 0; i < tree_.children(node); ++i)
+ {
+ stlplus::ntree<OctreeNode>::iterator child = tree_.child(node, i);
+
+ if (child.valid())
+ {
+ draw(child, alpha);
+ }
+ else
+ {
+ std::cerr << "node is not a leaf, but has an invalid child" << std::endl;
+ }
+
+ }
+}
+
+void Octree::drawIfVisible(stlplus::ntree<OctreeNode>::iterator node,
+ Scalar alpha, const Camera& cam)
+{
+ //node.drawIfVisible(alpha, cam);
+
+ if (!node.valid())
+ {
+ std::cerr << "invalid child while drawing :-(" << std::endl;
+ return;
+ }
+
+ Frustum::Collision collision =
+ cam.getFrustum().containsSphere(node->getSphere());
+ if (collision == Frustum::OUTSIDE) return;
+
+ collision = cam.getFrustum().containsAabb(node->getAabb());
+ if (collision == Frustum::OUTSIDE) return;
+
+
+ if (collision == Frustum::INSIDE)
+ {
+ node->draw(alpha);
+ }
+ else // collision == Frustum::INTERSECT
+ {
+ node->drawIfVisible(alpha, cam);
+ }
+
+ if (tree_.children(node) > 0)
+ {
+ if (collision == Frustum::INSIDE)
+ {
+ for (unsigned i = 0; i < tree_.children(node); ++i)
+ {
+ stlplus::ntree<OctreeNode>::iterator child = tree_.child(node, i);
+
+ if (child.valid())
+ {
+ draw(child, alpha);
+ }
+ else
+ {
+ std::cerr << "node is not a leaf, but has an invalid child" << std::endl;
+ }
+
+ }
+ }
+ else // collision == Frustum::INTERSECT
+ {
+ for (unsigned i = 0; i < tree_.children(node); ++i)
+ {
+ stlplus::ntree<OctreeNode>::iterator child = tree_.child(node, i);
+
+ if (child.valid())
+ {
+ drawIfVisible(child, alpha, cam);
+ }
+ else
+ {
+ std::cerr << "node is not a leaf, but has an invalid child" << std::endl;
+ }
+ }
+ }
+ }
+}
+
+
+} // namespace Mf
+
+/** vim: set ts=4 sw=4 tw=80: *************************************************/
+