Rename kD splay trees to Bounding Volume Splay Trees.

1 files changed, 0 insertions, 464 deletions

diff --git a/libdimension/kD_splay_tree.c b/libdimension/kD_splay_tree.c
deleted file mode 100644
index b6be801..0000000
--- a/libdimension/kD_splay_tree.c
+++ /dev/null
@@ -1,464 +0,0 @@
-/*************************************************************************
- * Copyright (C) 2009 Tavian Barnes <tavianator@gmail.com>               *
- *                                                                       *
- * This file is part of The Dimension Library.                           *
- *                                                                       *
- * The Dimension Library is free software; you can redistribute it and/  *
- * or modify it under the terms of the GNU Lesser General Public License *
- * as published by the Free Software Foundation; either version 3 of the *
- * License, or (at your option) any later version.                       *
- *                                                                       *
- * The Dimension Library 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  *
- * Lesser General Public License for more details.                       *
- *                                                                       *
- * You should have received a copy of the GNU Lesser General Public      *
- * License along with this program.  If not, see                         *
- * <http://www.gnu.org/licenses/>.                                       *
- *************************************************************************/
-
-#include "dimension_impl.h"
-#include <stdlib.h>
-
-static dmnsn_kD_splay_node *dmnsn_new_kD_splay_node();
-static void dmnsn_delete_kD_splay_node(dmnsn_kD_splay_node *node);
-
-/* Return an empty tree */
-dmnsn_kD_splay_tree *
-dmnsn_new_kD_splay_tree()
-{
-  dmnsn_kD_splay_tree *tree = malloc(sizeof(dmnsn_kD_splay_tree));
-  if (tree) {
-    tree->root = NULL;
-  } else {
-    dmnsn_error(DMNSN_SEVERITY_HIGH, "kD splay tree allocation failed.");
-  }
-  return tree;
-}
-
-/* Recursively copy the nodes of a kD splay tree */
-static dmnsn_kD_splay_node *
-dmnsn_kD_splay_copy_recursive(dmnsn_kD_splay_node *root)
-{
-  dmnsn_kD_splay_node *node = dmnsn_new_kD_splay_node();
-  *node = *root;
-  if (node->contains) {
-    node->contains = dmnsn_kD_splay_copy_recursive(node->contains);
-    node->contains->parent = node;
-  }
-  if (node->container) {
-    node->container = dmnsn_kD_splay_copy_recursive(node->container);
-    node->container->parent = node;
-  }
-  return node;
-}
-
-/* Copy a kD splay tree */
-dmnsn_kD_splay_tree *
-dmnsn_kD_splay_copy(dmnsn_kD_splay_tree *tree)
-{
-  dmnsn_kD_splay_tree *copy = dmnsn_new_kD_splay_tree();
-  if (tree->root)
-    copy->root = dmnsn_kD_splay_copy_recursive(tree->root);
-  else
-    copy->root = NULL;
-  return copy;
-}
-
-/* Recursively free a kD splay tree */
-void
-dmnsn_delete_kD_splay_tree_recursive(dmnsn_kD_splay_node *node)
-{
-  if (node) {
-    dmnsn_delete_kD_splay_tree_recursive(node->contains);
-    dmnsn_delete_kD_splay_tree_recursive(node->container);
-    dmnsn_delete_kD_splay_node(node);
-  }
-}
-
-/* Free a kD splay tree */
-void
-dmnsn_delete_kD_splay_tree(dmnsn_kD_splay_tree *tree)
-{
-  if (tree) {
-    dmnsn_delete_kD_splay_tree_recursive(tree->root);
-    free(tree);
-  }
-}
-
-/* Return whether node1 contains node2 */
-static int dmnsn_box_contains(dmnsn_vector p,
-                              dmnsn_vector min, dmnsn_vector max);
-/* Expand node to contain the bounding box from min to max */
-static void dmnsn_kD_splay_node_swallow(dmnsn_kD_splay_node *node,
-                                        dmnsn_vector min, dmnsn_vector max);
-
-/* Insert an object into the tree */
-void
-dmnsn_kD_splay_insert(dmnsn_kD_splay_tree *tree, dmnsn_object *object)
-{
-  dmnsn_kD_splay_node *node = dmnsn_new_kD_splay_node(), *parent = tree->root;
-
-  /* Store the inverse of the transformation matrix */
-  object->trans_inv = dmnsn_matrix_inverse(object->trans);
-
-  node->contains = NULL;
-  node->container = NULL;
-  node->parent = NULL;
-  node->object = object;
-
-  /* Calculate the new bounding box by finding the minimum coordinate of the
-     transformed corners of the object's original bounding box */
-
-  node->min = dmnsn_matrix_vector_mul(object->trans, object->min);
-  node->max = node->min;
-
-  dmnsn_vector corner;
-  corner = dmnsn_new_vector(object->min.x, object->min.y, object->max.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  corner = dmnsn_new_vector(object->min.x, object->max.y, object->min.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  corner = dmnsn_new_vector(object->min.x, object->max.y, object->max.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  corner = dmnsn_new_vector(object->max.x, object->min.y, object->min.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  corner = dmnsn_new_vector(object->max.x, object->min.y, object->max.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  corner = dmnsn_new_vector(object->max.x, object->max.y, object->min.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  corner = dmnsn_new_vector(object->max.x, object->max.y, object->max.z);
-  corner = dmnsn_matrix_vector_mul(object->trans, corner);
-  dmnsn_kD_splay_node_swallow(node, corner, corner);
-
-  /* Now insert the node */
-
-  while (parent) {
-    if (dmnsn_box_contains(node->min, parent->min, parent->max)
-        && dmnsn_box_contains(node->max, parent->min, parent->max)) {
-      /* parent fully contains node */
-      if (parent->contains)
-        parent = parent->contains;
-      else {
-        /* We found our parent; insert node into the tree */
-        parent->contains = node;
-        node->parent = parent;
-        break;
-      }
-    } else {
-      /* Expand node's bounding box to fully contain parent's if it doesn't
-         already */
-      dmnsn_kD_splay_node_swallow(node, parent->min, parent->max);
-      /* node now fully contains parent */
-      if (parent->container)
-        parent = parent->container;
-      else {
-        /* We found our parent; insert node into the tree */
-        parent->container = node;
-        node->parent = parent;
-        break;
-      }
-    }
-  }
-
-  dmnsn_kD_splay(tree, node);
-}
-
-/* Return whether p is within the axis-aligned box with corners min and max */
-static int
-dmnsn_box_contains(dmnsn_vector p, dmnsn_vector min, dmnsn_vector max)
-{
-  return (p.x >= min.x && p.y >= min.y && p.z >= min.z)
-    && (p.x <= max.x && p.y <= max.y && p.z <= max.z);
-}
-
-/* Expand node to contain the bounding box from min to max */
-static void
-dmnsn_kD_splay_node_swallow(dmnsn_kD_splay_node *node,
-                            dmnsn_vector min, dmnsn_vector max)
-{
-  if (node->min.x > min.x) node->min.x = min.x;
-  if (node->min.y > min.y) node->min.y = min.y;
-  if (node->min.z > min.z) node->min.z = min.z;
-
-  if (node->max.x < max.x) node->max.x = max.x;
-  if (node->max.y < max.y) node->max.y = max.y;
-  if (node->max.z < max.z) node->max.z = max.z;
-}
-
-/* Tree rotations */
-static void dmnsn_kD_splay_rotate(dmnsn_kD_splay_node *node);
-
-/* Splay a node: move it to the root via tree rotations */
-void
-dmnsn_kD_splay(dmnsn_kD_splay_tree *tree, dmnsn_kD_splay_node *node)
-{
-  while (node->parent) {
-    if (!node->parent->parent) {
-      /* Zig step - we are a child of the root node */
-      dmnsn_kD_splay_rotate(node);
-      break;
-    } else if ((node == node->parent->contains
-                && node->parent == node->parent->parent->contains)
-               || (node == node->parent->container
-                   && node->parent == node->parent->parent->container)) {
-      /* Zig-zig step - we are a child on the same side as our parent */
-      dmnsn_kD_splay_rotate(node->parent);
-      dmnsn_kD_splay_rotate(node);
-    } else {
-      /* Zig-zag step - we are a child on a different side than our parent is */
-      dmnsn_kD_splay_rotate(node);
-      dmnsn_kD_splay_rotate(node);
-    }
-  }
-  tree->root = node;
-}
-
-/* Rotate a tree on the edge connecting node and node->parent */
-static void
-dmnsn_kD_splay_rotate(dmnsn_kD_splay_node *node)
-{
-  dmnsn_kD_splay_node *P, *Q, *B;
-  if (node == node->parent->contains) {
-    /* We are a left child; perform a right rotation:
-     *
-     *     Q            P
-     *    / \          / \
-     *   P   C  --->  A   Q
-     *  / \              / \
-     * A   B            B   C
-     */
-    Q = node->parent;
-    P = node;
-    /* A = node->contains; */
-    B = node->container;
-    /* C = node->parent->container; */
-
-    /* First fix up the parents */
-    if (Q->parent) {
-      if (Q->parent->contains == Q)
-        Q->parent->contains = P;
-      else
-        Q->parent->container = P;
-    }
-    P->parent = Q->parent;
-    Q->parent = P;
-    if (B) B->parent = Q;
-
-    /* Then the children */
-    P->container = Q;
-    Q->contains  = B;
-  } else {
-    /* We are a right child; perform a left rotation:
-     *
-     *    P                Q
-     *   / \              / \
-     *  A   Q    --->    P   C
-     *     / \          / \
-     *    B   C        A   B
-     */
-    P = node->parent;
-    Q = node;
-    /* A = node->parent->contains; */
-    B = node->contains;
-    /* C = node->container; */
-
-    /* First fix up the parents */
-    if (P->parent) {
-      if (P->parent->contains == P)
-        P->parent->contains = Q;
-      else
-        P->parent->container = Q;
-    }
-    Q->parent = P->parent;
-    P->parent = Q;
-    if (B) B->parent = P;
-
-    /* Then the children */
-    Q->contains  = P;
-    P->container = B;
-  }
-}
-
-typedef struct {
-  dmnsn_kD_splay_node *node;
-  dmnsn_intersection  *intersection;
-} dmnsn_kD_splay_search_result;
-
-static dmnsn_kD_splay_search_result
-dmnsn_kD_splay_search_recursive(dmnsn_kD_splay_node *node, dmnsn_line ray,
-                                double t);
-
-dmnsn_intersection *
-dmnsn_kD_splay_search(dmnsn_kD_splay_tree *tree, dmnsn_line ray)
-{
-  dmnsn_kD_splay_search_result result
-    = dmnsn_kD_splay_search_recursive(tree->root, ray, -1.0);
-
-  if (result.node)
-    dmnsn_kD_splay(tree, result.node);
-
-  return result.intersection;
-}
-
-static int dmnsn_ray_box_intersection(dmnsn_line ray, dmnsn_vector min,
-                                      dmnsn_vector max, double t);
-
-static dmnsn_kD_splay_search_result
-dmnsn_kD_splay_search_recursive(dmnsn_kD_splay_node *node, dmnsn_line ray,
-                                double t)
-{
-  dmnsn_line ray_trans;
-  dmnsn_kD_splay_search_result result = { NULL, NULL }, result_temp;
-
-  if (!node)
-    return result;
-
-  /* Go down the right subtree first because the closest object is more likely
-     to lie in the larger bounding boxes */
-  result_temp = dmnsn_kD_splay_search_recursive(node->container, ray, t);
-  if (result_temp.node && (t < 0.0 || result_temp.intersection->t < t)) {
-    result = result_temp;
-    t = result.intersection->t;
-  } else {
-    dmnsn_delete_intersection(result_temp.intersection);
-  }
-
-  if (dmnsn_box_contains(ray.x0, node->min, node->max)
-      || dmnsn_ray_box_intersection(ray, node->min, node->max, t))
-  {
-    /* Transform the ray according to the object */
-    ray_trans = dmnsn_matrix_line_mul(node->object->trans_inv, ray);
-
-    if (dmnsn_box_contains(ray_trans.x0, node->object->min, node->object->max)
-        || dmnsn_ray_box_intersection(ray_trans, node->object->min,
-                                      node->object->max, t))
-    {
-      result_temp.intersection =
-        (*node->object->intersection_fn)(node->object, ray_trans);
-
-      if (result_temp.intersection
-          && (t < 0.0 || result_temp.intersection->t < t)) {
-        dmnsn_delete_intersection(result.intersection);
-        result.node = node;
-        result.intersection = result_temp.intersection;
-        t = result.intersection->t;
-
-        /* Transform the intersection back to the observer's view */
-        result.intersection->ray = ray;
-        result.intersection->normal = dmnsn_vector_normalize(
-          dmnsn_vector_sub(
-            dmnsn_matrix_vector_mul(
-              node->object->trans,
-              result.intersection->normal
-            ),
-            dmnsn_matrix_vector_mul(
-              node->object->trans,
-              dmnsn_zero
-            )
-          )
-        );
-      } else {
-        dmnsn_delete_intersection(result_temp.intersection);
-      }
-    }
-
-    /* Go down the left subtree */
-    result_temp = dmnsn_kD_splay_search_recursive(node->contains, ray, t);
-    if (result_temp.node && (t < 0.0 || result_temp.intersection->t < t)) {
-      dmnsn_delete_intersection(result.intersection);
-      result = result_temp;
-      t = result.intersection->t;
-    } else {
-      dmnsn_delete_intersection(result_temp.intersection);
-    }
-  }
-
-  return result;
-}
-
-static int
-dmnsn_ray_box_intersection(dmnsn_line line, dmnsn_vector min, dmnsn_vector max,
-                           double t)
-{
-  double t_temp;
-  dmnsn_vector p;
-
-  if (line.n.x != 0.0) {
-    /* x == min.x */
-    t_temp = (min.x - line.x0.x)/line.n.x;
-    p = dmnsn_line_point(line, t_temp);
-    if (p.y >= min.y && p.y <= max.y && p.z >= min.z && p.z <= max.z
-        && t_temp >= 0.0 && (t < 0.0 || t_temp < t))
-      return 1;
-
-    /* x == max.x */
-    t_temp = (max.x - line.x0.x)/line.n.x;
-    p = dmnsn_line_point(line, t_temp);
-    if (p.y >= min.y && p.y <= max.y && p.z >= min.z && p.z <= max.z
-        && t_temp >= 0.0 && (t < 0.0 || t_temp < t))
-      return 1;
-  }
-
-  if (line.n.y != 0.0) {
-    /* y == -1.0 */
-    t_temp = (min.y - line.x0.y)/line.n.y;
-    p = dmnsn_line_point(line, t_temp);
-    if (p.x >= min.x && p.x <= max.x && p.z >= min.z && p.z <= max.z
-        && t_temp >= 0.0 && (t < 0.0 || t_temp < t))
-      return 1;
-
-    /* y == 1.0 */
-    t_temp = (max.y - line.x0.y)/line.n.y;
-    p = dmnsn_line_point(line, t_temp);
-    if (p.x >= min.x && p.x <= max.x && p.z >= min.z && p.z <= max.z
-        && t_temp >= 0.0 && (t < 0.0 || t_temp < t))
-      return 1;
-  }
-
-  if (line.n.z != 0.0) {
-    /* z == -1.0 */
-    t_temp = (min.z - line.x0.z)/line.n.z;
-    p = dmnsn_line_point(line, t_temp);
-    if (p.x >= min.x && p.x <= max.x && p.y >= min.y && p.y <= max.y
-        && t_temp >= 0.0 && (t < 0.0 || t_temp < t))
-      return 1;
-
-    /* z == 1.0 */
-    t_temp = (max.z - line.x0.z)/line.n.z;
-    p = dmnsn_line_point(line, t_temp);
-    if (p.x >= min.x && p.x <= max.x && p.y >= min.y && p.y <= max.y
-        && t_temp >= 0.0 && (t < 0.0 || t_temp < t))
-      return 1;
-  }
-
-  return 0;
-}
-
-static dmnsn_kD_splay_node *
-dmnsn_new_kD_splay_node()
-{
-  dmnsn_kD_splay_node *node = malloc(sizeof(dmnsn_kD_splay_node));
-  if (!node) {
-    dmnsn_error(DMNSN_SEVERITY_HIGH, "kD splay tree node allocation failed.");
-  }
-  return node;
-}
-
-static void
-dmnsn_delete_kD_splay_node(dmnsn_kD_splay_node *node)
-{
-  free(node);
-}