#ifndef BVH_H
#define BVH_H
#include "common.h"
+#include "distq.h"
/*
* Usage:
bh_system *system;
void *user;
+ u32 max_per_leaf;
struct bh_node
{
boxf bbx;
/* if il is 0, this is a leaf */
- u32 il, count;
- union{ u32 ir, start; };
+ int il, count;
+ union{ int ir, start; };
}
nodes[];
};
{
void (*expand_bound)( void *user, boxf bound, u32 item_index );
float (*item_centroid)( void *user, u32 item_index, int axis );
+ void (*item_closest)( void *user, u32 item_index, v3f point, v3f closest );
void (*item_swap)( void *user, u32 ia, u32 ib );
/*
{
bh_node *node = &bh->nodes[ inode ];
+ if( node->count <= bh->max_per_leaf )
+ return;
+
v3f extent;
v3_sub( node->bbx[1], node->bbx[0], extent );
}
VG_STATIC bh_tree *bh_create( void *lin_alloc, bh_system *system,
- void *user, u32 item_count )
+ void *user, u32 item_count, u32 max_per_leaf )
{
+ assert( max_per_leaf > 0 );
+
if( item_count == 0 )
{
bh_tree *bh = vg_linear_alloc( lin_alloc, sizeof(bh_tree) );
bh_tree *bh = vg_linear_alloc( lin_alloc, totsize );
bh->system = system;
bh->user = user;
+ bh->max_per_leaf = max_per_leaf;
bh_node *root = &bh->nodes[0];
bh->node_count = 1;
return count;
}
-VG_STATIC int bh_select( bh_tree *bh, boxf box, u32 *buffer, int len )
+typedef struct bh_iter bh_iter;
+struct bh_iter
{
- if( bh->node_count < 2 )
- return 0;
+ struct
+ {
+ int id, depth;
+ }
+ stack[64];
- int count = 0;
- u32 stack[100];
- u32 depth = 2;
+ int depth, i;
+};
- stack[0] = 0;
- stack[1] = bh->nodes[0].il;
- stack[2] = bh->nodes[0].ir;
-
- while(depth)
+VG_STATIC void bh_iter_init( int root, bh_iter *it )
+{
+ it->stack[0].id = root;
+ it->stack[0].depth = 0;
+ it->depth = 0;
+ it->i = 0;
+}
+
+VG_STATIC int bh_next( bh_tree *bh, bh_iter *it, boxf box, int *em )
+{
+ while( it->depth >= 0 )
{
- bh_node *inode = &bh->nodes[ stack[depth] ];
+ bh_node *inode = &bh->nodes[ it->stack[it->depth].id ];
+
if( box_overlap( inode->bbx, box ) )
{
if( inode->count )
{
- if( count + inode->count >= len )
- return count;
-
- for( u32 i=0; i<inode->count; i++ )
- buffer[ count ++ ] = inode->start+i;
-
- depth --;
+ if( it->i < inode->count )
+ {
+ *em = inode->start+it->i;
+ it->i ++;
+ return 1;
+ }
+ else
+ {
+ it->depth --;
+ it->i = 0;
+ }
}
else
{
- if( depth+1 >= vg_list_size(stack) )
+ if( it->depth+1 >= vg_list_size(it->stack) )
{
vg_error( "Maximum stack reached!\n" );
- return count;
+ return 0;
}
- stack[depth] = inode->il;
- stack[depth+1] = inode->ir;
- depth ++;
+ it->stack[it->depth ].id = inode->il;
+ it->stack[it->depth+1].id = inode->ir;
+ it->depth ++;
+ it->i = 0;
}
}
else
{
- depth --;
+ it->depth --;
}
}
- return count;
+ return 0;
+}
+
+VG_STATIC int bh_closest_point( bh_tree *bh, v3f pos,
+ v3f closest, float max_dist )
+{
+ if( bh->node_count < 2 )
+ return -1;
+
+ max_dist = max_dist*max_dist;
+
+ int queue[ 128 ],
+ depth = 0,
+ best_item = -1;
+
+ queue[0] = 0;
+
+ while( depth >= 0 )
+ {
+ bh_node *inode = &bh->nodes[ queue[depth] ];
+
+ v3f p1;
+ closest_point_aabb( pos, inode->bbx, p1 );
+
+ /* branch into node if its closer than current best */
+ float node_dist = v3_dist2( pos, p1 );
+ if( node_dist < max_dist )
+ {
+ if( inode->count )
+ {
+ for( int i=0; i<inode->count; i++ )
+ {
+ v3f p2;
+ bh->system->item_closest( bh->user, inode->start+i, pos, p2 );
+
+ float item_dist = v3_dist2( pos, p2 );
+ if( item_dist < max_dist )
+ {
+ max_dist = item_dist;
+ v3_copy( p2, closest );
+ best_item = inode->start+i;
+ }
+ }
+
+ depth --;
+ }
+ else
+ {
+ queue[depth] = inode->il;
+ queue[depth+1] = inode->ir;
+
+ depth ++;
+ }
+ }
+ else
+ depth --;
+ }
+
+ return best_item;
}
#endif /* BVH_H */