690e07b509
Complete rewrite of spatial partitioning using a bounding volume hierarchy rather than octree. Switchable in project settings between using octree or BVH for rendering and physics.
253 lines
7.6 KiB
C++
253 lines
7.6 KiB
C++
/*************************************************************************/
|
|
/* bvh_abb.h */
|
|
/*************************************************************************/
|
|
/* This file is part of: */
|
|
/* GODOT ENGINE */
|
|
/* https://godotengine.org */
|
|
/*************************************************************************/
|
|
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
|
|
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md). */
|
|
/* */
|
|
/* Permission is hereby granted, free of charge, to any person obtaining */
|
|
/* a copy of this software and associated documentation files (the */
|
|
/* "Software"), to deal in the Software without restriction, including */
|
|
/* without limitation the rights to use, copy, modify, merge, publish, */
|
|
/* distribute, sublicense, and/or sell copies of the Software, and to */
|
|
/* permit persons to whom the Software is furnished to do so, subject to */
|
|
/* the following conditions: */
|
|
/* */
|
|
/* The above copyright notice and this permission notice shall be */
|
|
/* included in all copies or substantial portions of the Software. */
|
|
/* */
|
|
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
|
|
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
|
|
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
|
|
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
|
|
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
|
|
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
|
|
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
|
|
/*************************************************************************/
|
|
|
|
#ifndef BVH_ABB_H
|
|
#define BVH_ABB_H
|
|
|
|
// special optimized version of axis aligned bounding box
|
|
struct BVH_ABB {
|
|
struct ConvexHull {
|
|
// convex hulls (optional)
|
|
const Plane *planes;
|
|
int num_planes;
|
|
const Vector3 *points;
|
|
int num_points;
|
|
};
|
|
|
|
struct Segment {
|
|
Vector3 from;
|
|
Vector3 to;
|
|
};
|
|
|
|
enum IntersectResult {
|
|
IR_MISS = 0,
|
|
IR_PARTIAL,
|
|
IR_FULL,
|
|
};
|
|
|
|
// we store mins with a negative value in order to test them with SIMD
|
|
Vector3 min;
|
|
Vector3 neg_max;
|
|
|
|
bool operator==(const BVH_ABB &o) const { return (min == o.min) && (neg_max == o.neg_max); }
|
|
bool operator!=(const BVH_ABB &o) const { return (*this == o) == false; }
|
|
|
|
void set(const Vector3 &_min, const Vector3 &_max) {
|
|
min = _min;
|
|
neg_max = -_max;
|
|
}
|
|
|
|
// to and from standard AABB
|
|
void from(const AABB &p_aabb) {
|
|
min = p_aabb.position;
|
|
neg_max = -(p_aabb.position + p_aabb.size);
|
|
}
|
|
|
|
void to(AABB &r_aabb) const {
|
|
r_aabb.position = min;
|
|
r_aabb.size = calculate_size();
|
|
}
|
|
|
|
void merge(const BVH_ABB &p_o) {
|
|
neg_max.x = MIN(neg_max.x, p_o.neg_max.x);
|
|
neg_max.y = MIN(neg_max.y, p_o.neg_max.y);
|
|
neg_max.z = MIN(neg_max.z, p_o.neg_max.z);
|
|
|
|
min.x = MIN(min.x, p_o.min.x);
|
|
min.y = MIN(min.y, p_o.min.y);
|
|
min.z = MIN(min.z, p_o.min.z);
|
|
}
|
|
|
|
Vector3 calculate_size() const {
|
|
return -neg_max - min;
|
|
}
|
|
|
|
Vector3 calculate_centre() const {
|
|
return Vector3((calculate_size() * 0.5) + min);
|
|
}
|
|
|
|
real_t get_proximity_to(const BVH_ABB &p_b) const {
|
|
const Vector3 d = (min - neg_max) - (p_b.min - p_b.neg_max);
|
|
return (Math::abs(d.x) + Math::abs(d.y) + Math::abs(d.z));
|
|
}
|
|
|
|
int select_by_proximity(const BVH_ABB &p_a, const BVH_ABB &p_b) const {
|
|
return (get_proximity_to(p_a) < get_proximity_to(p_b) ? 0 : 1);
|
|
}
|
|
|
|
uint32_t find_cutting_planes(const BVH_ABB::ConvexHull &p_hull, uint32_t *p_plane_ids) const {
|
|
uint32_t count = 0;
|
|
|
|
for (int n = 0; n < p_hull.num_planes; n++) {
|
|
const Plane &p = p_hull.planes[n];
|
|
if (intersects_plane(p)) {
|
|
p_plane_ids[count++] = n;
|
|
}
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
bool intersects_plane(const Plane &p_p) const {
|
|
Vector3 size = calculate_size();
|
|
Vector3 half_extents = size * 0.5;
|
|
Vector3 ofs = min + half_extents;
|
|
|
|
// forward side of plane?
|
|
Vector3 point_offset(
|
|
(p_p.normal.x < 0) ? -half_extents.x : half_extents.x,
|
|
(p_p.normal.y < 0) ? -half_extents.y : half_extents.y,
|
|
(p_p.normal.z < 0) ? -half_extents.z : half_extents.z);
|
|
Vector3 point = point_offset + ofs;
|
|
|
|
if (!p_p.is_point_over(point))
|
|
return false;
|
|
|
|
point = -point_offset + ofs;
|
|
if (p_p.is_point_over(point))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool intersects_convex_optimized(const ConvexHull &p_hull, const uint32_t *p_plane_ids, uint32_t p_num_planes) const {
|
|
Vector3 size = calculate_size();
|
|
Vector3 half_extents = size * 0.5;
|
|
Vector3 ofs = min + half_extents;
|
|
|
|
for (unsigned int i = 0; i < p_num_planes; i++) {
|
|
|
|
const Plane &p = p_hull.planes[p_plane_ids[i]];
|
|
Vector3 point(
|
|
(p.normal.x > 0) ? -half_extents.x : half_extents.x,
|
|
(p.normal.y > 0) ? -half_extents.y : half_extents.y,
|
|
(p.normal.z > 0) ? -half_extents.z : half_extents.z);
|
|
point += ofs;
|
|
if (p.is_point_over(point))
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool intersects_convex_partial(const ConvexHull &p_hull) const {
|
|
AABB bb;
|
|
to(bb);
|
|
return bb.intersects_convex_shape(p_hull.planes, p_hull.num_planes, p_hull.points, p_hull.num_points);
|
|
}
|
|
|
|
IntersectResult intersects_convex(const ConvexHull &p_hull) const {
|
|
if (intersects_convex_partial(p_hull)) {
|
|
// fully within? very important for tree checks
|
|
if (is_within_convex(p_hull)) {
|
|
return IR_FULL;
|
|
}
|
|
|
|
return IR_PARTIAL;
|
|
}
|
|
|
|
return IR_MISS;
|
|
}
|
|
|
|
bool is_within_convex(const ConvexHull &p_hull) const {
|
|
// use half extents routine
|
|
AABB bb;
|
|
to(bb);
|
|
return bb.inside_convex_shape(p_hull.planes, p_hull.num_planes);
|
|
}
|
|
|
|
bool is_point_within_hull(const ConvexHull &p_hull, const Vector3 &p_pt) const {
|
|
for (int n = 0; n < p_hull.num_planes; n++) {
|
|
if (p_hull.planes[n].distance_to(p_pt) > 0.0f)
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool intersects_segment(const Segment &p_s) const {
|
|
AABB bb;
|
|
to(bb);
|
|
return bb.intersects_segment(p_s.from, p_s.to);
|
|
}
|
|
|
|
bool intersects_point(const Vector3 &p_pt) const {
|
|
if (_vector3_any_lessthan(-p_pt, neg_max)) return false;
|
|
if (_vector3_any_lessthan(p_pt, min)) return false;
|
|
return true;
|
|
}
|
|
|
|
bool intersects(const BVH_ABB &p_o) const {
|
|
if (_vector3_any_morethan(p_o.min, -neg_max)) return false;
|
|
if (_vector3_any_morethan(min, -p_o.neg_max)) return false;
|
|
return true;
|
|
}
|
|
|
|
bool is_other_within(const BVH_ABB &p_o) const {
|
|
if (_vector3_any_lessthan(p_o.neg_max, neg_max)) return false;
|
|
if (_vector3_any_lessthan(p_o.min, min)) return false;
|
|
return true;
|
|
}
|
|
|
|
void grow(const Vector3 &p_change) {
|
|
neg_max -= p_change;
|
|
min -= p_change;
|
|
}
|
|
|
|
void expand(real_t p_change) {
|
|
grow(Vector3(p_change, p_change, p_change));
|
|
}
|
|
|
|
float get_area() const // actually surface area metric
|
|
{
|
|
Vector3 d = calculate_size();
|
|
return 2.0f * (d.x * d.y + d.y * d.z + d.z * d.x);
|
|
}
|
|
void set_to_max_opposite_extents() {
|
|
neg_max = Vector3(FLT_MAX, FLT_MAX, FLT_MAX);
|
|
min = neg_max;
|
|
}
|
|
|
|
bool _vector3_any_morethan(const Vector3 &p_a, const Vector3 &p_b) const {
|
|
if (p_a.x > p_b.x) return true;
|
|
if (p_a.y > p_b.y) return true;
|
|
if (p_a.z > p_b.z) return true;
|
|
return false;
|
|
}
|
|
|
|
bool _vector3_any_lessthan(const Vector3 &p_a, const Vector3 &p_b) const {
|
|
if (p_a.x < p_b.x) return true;
|
|
if (p_a.y < p_b.y) return true;
|
|
if (p_a.z < p_b.z) return true;
|
|
return false;
|
|
}
|
|
};
|
|
|
|
#endif // BVH_ABB_H
|