Modularize the libdimension codebase.

1 files changed, 0 insertions, 404 deletions

diff --git a/libdimension/bvh.c b/libdimension/bvh.c
deleted file mode 100644
index d1bd0fc..0000000
--- a/libdimension/bvh.c
+++ /dev/null
@@ -1,404 +0,0 @@
-/*************************************************************************
- * Copyright (C) 2012-2014 Tavian Barnes <tavianator@tavianator.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/>.                                       *
- *************************************************************************/
-
-/**
- * @file
- * BVH implementation.  These are the hottest code paths in libdimension.
- */
-
-#include "dimension-internal.h"
-
-/// Implementation for DMNSN_BVH_NONE: just stick all objects in one node.
-static dmnsn_bvh_node *
-dmnsn_new_stupid_bvh(const dmnsn_array *objects)
-{
-  dmnsn_bvh_node *root = dmnsn_new_bvh_node(dmnsn_array_size(objects));
-
-  DMNSN_ARRAY_FOREACH (dmnsn_object **, object, objects) {
-    dmnsn_bvh_node *leaf = dmnsn_new_bvh_leaf_node(*object);
-    dmnsn_bvh_node_add(root, leaf);
-  }
-
-  return root;
-}
-
-// Implementation of opaque dmnsn_bvh type.
-struct dmnsn_bvh {
-  dmnsn_array *unbounded;           ///< The unbounded objects.
-  dmnsn_array *bounded;             ///< The BVH of the bounded objects.
-  pthread_key_t intersection_cache; ///< The thread-local intersection cache.
-};
-
-/// A flat BVH node for storing in an array for fast pre-order traversal.
-typedef struct dmnsn_flat_bvh_node {
-  dmnsn_bounding_box bounding_box; // The bounding box of this node.
-  dmnsn_object *object;            // The referenced object, for leaf nodes.
-  ptrdiff_t skip;                  // Displacement to the next sibling.
-} dmnsn_flat_bvh_node;
-
-/// Add an object or its children, if any, to an array.
-static void
-dmnsn_split_add_object(dmnsn_array *objects, const dmnsn_object *object)
-{
-  if (object->split_children) {
-    DMNSN_ARRAY_FOREACH (const dmnsn_object **, child, object->children) {
-      dmnsn_split_add_object(objects, *child);
-    }
-  } else {
-    dmnsn_array_push(objects, &object);
-  }
-}
-
-/// Split unions to create the input for the BVH.
-static dmnsn_array *
-dmnsn_split_objects(const dmnsn_array *objects)
-{
-  dmnsn_array *split = DMNSN_NEW_ARRAY(dmnsn_object *);
-  DMNSN_ARRAY_FOREACH (const dmnsn_object **, object, objects) {
-    dmnsn_split_add_object(split, *object);
-  }
-  return split;
-}
-
-/// Split unbounded objects into a new array.
-static dmnsn_array *
-dmnsn_split_unbounded(dmnsn_array *objects)
-{
-  dmnsn_array *unbounded = DMNSN_NEW_ARRAY(dmnsn_object *);
-
-  dmnsn_object **array = dmnsn_array_first(objects);
-  size_t i, skip;
-  for (i = 0, skip = 0; i < dmnsn_array_size(objects); ++i) {
-    if (dmnsn_bounding_box_is_infinite(array[i]->bounding_box)) {
-      dmnsn_array_push(unbounded, &array[i]);
-      ++skip;
-    } else {
-      array[i - skip] = array[i];
-    }
-  }
-  dmnsn_array_resize(objects, i - skip);
-
-  return unbounded;
-}
-
-/// Recursively flatten a BVH into an array of flat nodes.
-static void
-dmnsn_flatten_bvh_recursive(dmnsn_bvh_node *node, dmnsn_array *flat)
-{
-  size_t currenti = dmnsn_array_size(flat);
-  dmnsn_array_resize(flat, currenti + 1);
-  dmnsn_flat_bvh_node *flatnode = dmnsn_array_at(flat, currenti);
-
-  flatnode->bounding_box = node->bounding_box;
-  flatnode->object       = node->object;
-
-  for (size_t i = 0; i < node->nchildren && node->children[i]; ++i) {
-    dmnsn_flatten_bvh_recursive(node->children[i], flat);
-  }
-
-  // Array could have been realloc()'d somewhere else above
-  flatnode = dmnsn_array_at(flat, currenti);
-  flatnode->skip = dmnsn_array_size(flat) - currenti;
-}
-
-/// Flatten a BVH into an array of flat nodes.
-static dmnsn_array *
-dmnsn_flatten_bvh(dmnsn_bvh_node *root)
-{
-  dmnsn_array *flat = DMNSN_NEW_ARRAY(dmnsn_flat_bvh_node);
-  if (root) {
-    dmnsn_flatten_bvh_recursive(root, flat);
-  }
-  return flat;
-}
-
-dmnsn_bvh *dmnsn_new_bvh(const dmnsn_array *objects, dmnsn_bvh_kind kind)
-{
-  dmnsn_bvh *bvh = DMNSN_MALLOC(dmnsn_bvh);
-
-  dmnsn_array *bounded = dmnsn_split_objects(objects);
-  bvh->unbounded = dmnsn_split_unbounded(bounded);
-
-  dmnsn_bvh_node *root = NULL;
-  if (dmnsn_array_size(bounded) > 0) {
-    switch (kind) {
-    case DMNSN_BVH_NONE:
-      root = dmnsn_new_stupid_bvh(bounded);
-      break;
-    case DMNSN_BVH_PRTREE:
-      root = dmnsn_new_prtree(bounded);
-      break;
-    default:
-      dmnsn_unreachable("Invalid BVH kind.");
-    }
-  }
-  bvh->bounded = dmnsn_flatten_bvh(root);
-
-  dmnsn_delete_bvh_node(root);
-  dmnsn_delete_array(bounded);
-
-  dmnsn_key_create(&bvh->intersection_cache, dmnsn_free);
-
-  return bvh;
-}
-
-void
-dmnsn_delete_bvh(dmnsn_bvh *bvh)
-{
-  if (bvh) {
-    dmnsn_free(pthread_getspecific(bvh->intersection_cache));
-    dmnsn_key_delete(bvh->intersection_cache);
-    dmnsn_delete_array(bvh->bounded);
-    dmnsn_delete_array(bvh->unbounded);
-    dmnsn_free(bvh);
-  }
-}
-
-/// A line with pre-calculated reciprocals to avoid divisions.
-typedef struct dmnsn_optimized_line {
-  dmnsn_vector x0;    ///< The origin of the line.
-  dmnsn_vector n_inv; ///< The inverse of each component of the line's slope
-} dmnsn_optimized_line;
-
-/// Precompute inverses for faster ray-box intersection tests.
-static inline dmnsn_optimized_line
-dmnsn_optimize_line(dmnsn_line line)
-{
-  dmnsn_optimized_line optline = {
-    .x0    = line.x0,
-    .n_inv = dmnsn_new_vector(1.0/line.n.x, 1.0/line.n.y, 1.0/line.n.z)
-  };
-  return optline;
-}
-
-/// Ray-AABB intersection test, by the slab method.  Highly optimized.
-static inline bool
-dmnsn_ray_box_intersection(dmnsn_optimized_line optline,
-                           dmnsn_bounding_box box, double t)
-{
-  // This is actually correct, even though it appears not to handle edge cases
-  // (line.n.{x,y,z} == 0).  It works because the infinities that result from
-  // dividing by zero will still behave correctly in the comparisons.  Lines
-  // which are parallel to an axis and outside the box will have tmin == inf
-  // or tmax == -inf, while lines inside the box will have tmin and tmax
-  // unchanged.
-
-  double tx1 = (box.min.x - optline.x0.x)*optline.n_inv.x;
-  double tx2 = (box.max.x - optline.x0.x)*optline.n_inv.x;
-
-  double tmin = dmnsn_min(tx1, tx2);
-  double tmax = dmnsn_max(tx1, tx2);
-
-  double ty1 = (box.min.y - optline.x0.y)*optline.n_inv.y;
-  double ty2 = (box.max.y - optline.x0.y)*optline.n_inv.y;
-
-  tmin = dmnsn_max(tmin, dmnsn_min(ty1, ty2));
-  tmax = dmnsn_min(tmax, dmnsn_max(ty1, ty2));
-
-  double tz1 = (box.min.z - optline.x0.z)*optline.n_inv.z;
-  double tz2 = (box.max.z - optline.x0.z)*optline.n_inv.z;
-
-  tmin = dmnsn_max(tmin, dmnsn_min(tz1, tz2));
-  tmax = dmnsn_min(tmax, dmnsn_max(tz1, tz2));
-
-  return tmax >= dmnsn_max(0.0, tmin) && tmin < t;
-}
-
-/// The number of intersections to cache.
-#define DMNSN_INTERSECTION_CACHE_SIZE 32
-
-/// An array of cached intersections.
-typedef struct dmnsn_intersection_cache {
-  size_t i;
-  dmnsn_object *objects[DMNSN_INTERSECTION_CACHE_SIZE];
-} dmnsn_intersection_cache;
-
-static dmnsn_intersection_cache *
-dmnsn_get_intersection_cache(const dmnsn_bvh *bvh)
-{
-  dmnsn_intersection_cache *cache
-    = pthread_getspecific(bvh->intersection_cache);
-
-  if (!cache) {
-    cache = DMNSN_MALLOC(dmnsn_intersection_cache);
-    cache->i = 0;
-    for (size_t i = 0; i < DMNSN_INTERSECTION_CACHE_SIZE; ++i) {
-      cache->objects[i] = NULL;
-    }
-    dmnsn_setspecific(bvh->intersection_cache, cache);
-  }
-
-  return cache;
-}
-
-/// Test for a closer object intersection than we've found so far.
-static inline bool
-dmnsn_closer_intersection(dmnsn_object *object, dmnsn_line ray,
-                          dmnsn_intersection *intersection, double *t)
-{
-  dmnsn_intersection local_intersection;
-  if (dmnsn_object_intersection(object, ray, &local_intersection)) {
-    if (local_intersection.t < *t) {
-      *intersection = local_intersection;
-      *t = local_intersection.t;
-      return true;
-    }
-  }
-  return false;
-}
-
-DMNSN_HOT bool
-dmnsn_bvh_intersection(const dmnsn_bvh *bvh, dmnsn_line ray,
-                       dmnsn_intersection *intersection, bool reset)
-{
-  double t = INFINITY;
-
-  // Search the unbounded objects
-  DMNSN_ARRAY_FOREACH (dmnsn_object **, object, bvh->unbounded) {
-    dmnsn_closer_intersection(*object, ray, intersection, &t);
-  }
-
-  // Precalculate 1.0/ray.n.{x,y,z} to save time in intersection tests
-  dmnsn_optimized_line optline = dmnsn_optimize_line(ray);
-
-  // Search the intersection cache
-  dmnsn_intersection_cache *cache = dmnsn_get_intersection_cache(bvh);
-  if (dmnsn_unlikely(reset)) {
-    cache->i = 0;
-  }
-  dmnsn_object *cached = NULL, *found = NULL;
-  if (dmnsn_likely(cache->i < DMNSN_INTERSECTION_CACHE_SIZE)) {
-    cached = cache->objects[cache->i];
-  }
-  if (cached && dmnsn_ray_box_intersection(optline, cached->bounding_box, t)) {
-    if (dmnsn_closer_intersection(cached, ray, intersection, &t)) {
-      found = cached;
-    }
-  }
-
-  // Search the bounded objects
-  dmnsn_flat_bvh_node *node = dmnsn_array_first(bvh->bounded);
-  dmnsn_flat_bvh_node *last = dmnsn_array_last(bvh->bounded);
-  while (node <= last) {
-    if (dmnsn_ray_box_intersection(optline, node->bounding_box, t)) {
-      if (node->object && node->object != cached) {
-        if (dmnsn_closer_intersection(node->object, ray, intersection, &t)) {
-          found = node->object;
-        }
-      }
-      ++node;
-    } else {
-      node += node->skip;
-    }
-  }
-
-  // Update the cache
-  if (dmnsn_likely(cache->i < DMNSN_INTERSECTION_CACHE_SIZE)) {
-    cache->objects[cache->i] = found;
-    ++cache->i;
-  }
-
-  return !isinf(t);
-}
-
-DMNSN_HOT bool
-dmnsn_bvh_inside(const dmnsn_bvh *bvh, dmnsn_vector point)
-{
-  // Search the unbounded objects
-  DMNSN_ARRAY_FOREACH (dmnsn_object **, object, bvh->unbounded) {
-    if (dmnsn_object_inside(*object, point))
-      return true;
-  }
-
-  // Search the bounded objects
-  dmnsn_flat_bvh_node *node = dmnsn_array_first(bvh->bounded);
-  dmnsn_flat_bvh_node *last = dmnsn_array_last(bvh->bounded);
-  while (node <= last) {
-    if (dmnsn_bounding_box_contains(node->bounding_box, point)) {
-      if (node->object && dmnsn_object_inside(node->object, point)) {
-        return true;
-      }
-      ++node;
-    } else {
-      node += node->skip;
-    }
-  }
-
-  return false;
-}
-
-dmnsn_bounding_box
-dmnsn_bvh_bounding_box(const dmnsn_bvh *bvh)
-{
-  if (dmnsn_array_size(bvh->unbounded) > 0) {
-    return dmnsn_infinite_bounding_box();
-  } else if (dmnsn_array_size(bvh->bounded) > 0) {
-    dmnsn_flat_bvh_node *root = dmnsn_array_first(bvh->bounded);
-    return root->bounding_box;
-  } else {
-    return dmnsn_zero_bounding_box();
-  }
-}
-
-dmnsn_bvh_node *
-dmnsn_new_bvh_node(unsigned int max_children)
-{
-  dmnsn_bvh_node *node = dmnsn_malloc(sizeof(dmnsn_bvh_node) + max_children*sizeof(dmnsn_bvh_node *));
-  node->bounding_box = dmnsn_zero_bounding_box();
-  node->object = NULL;
-  node->nchildren = 0;
-  node->max_children = max_children;
-  return node;
-}
-
-dmnsn_bvh_node *
-dmnsn_new_bvh_leaf_node(dmnsn_object *object)
-{
-  dmnsn_bvh_node *node = DMNSN_MALLOC(dmnsn_bvh_node);
-  node->bounding_box = object->bounding_box;
-  node->object = object;
-  node->nchildren = 0;
-  node->max_children = 0;
-  return node;
-}
-
-void
-dmnsn_delete_bvh_node(dmnsn_bvh_node *node)
-{
-  if (node) {
-    for (size_t i = 0; i < node->nchildren; ++i) {
-      dmnsn_delete_bvh_node(node->children[i]);
-    }
-    dmnsn_free(node);
-  }
-}
-
-void
-dmnsn_bvh_node_add(dmnsn_bvh_node *parent, dmnsn_bvh_node *child)
-{
-  dmnsn_assert(parent->nchildren < parent->max_children,
-               "Too many BVH children inserted.");
-
-  parent->bounding_box.min = dmnsn_vector_min(parent->bounding_box.min,
-                                              child->bounding_box.min);
-  parent->bounding_box.max = dmnsn_vector_max(parent->bounding_box.max,
-                                              child->bounding_box.max);
-  parent->children[parent->nchildren++] = child;
-}