💿🐜 Antkeeper source code
https://antkeeper.com
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
111 lines
2.9 KiB
111 lines
2.9 KiB
/*
|
|
* Copyright (C) 2023 Christopher J. Howard
|
|
*
|
|
* This file is part of Antkeeper source code.
|
|
*
|
|
* Antkeeper source code is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* Antkeeper source code 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 General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with Antkeeper source code. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <engine/physics/kinematics/colliders/mesh-collider.hpp>
|
|
#include <engine/debug/log.hpp>
|
|
#include <engine/geom/intersection.hpp>
|
|
#include <limits>
|
|
|
|
namespace physics {
|
|
|
|
mesh_collider::mesh_collider(std::shared_ptr<mesh_type> mesh)
|
|
{
|
|
set_mesh(mesh);
|
|
}
|
|
|
|
void mesh_collider::set_mesh(std::shared_ptr<mesh_type> mesh)
|
|
{
|
|
m_mesh = mesh;
|
|
if (m_mesh)
|
|
{
|
|
m_vertex_positions = &m_mesh->vertices().attributes().at<math::fvec3>("position");
|
|
}
|
|
else
|
|
{
|
|
m_vertex_positions = nullptr;
|
|
}
|
|
|
|
rebuild_bvh();
|
|
}
|
|
|
|
void mesh_collider::rebuild_bvh()
|
|
{
|
|
if (m_mesh)
|
|
{
|
|
m_bvh.build(*m_mesh);
|
|
}
|
|
else
|
|
{
|
|
m_bvh.clear();
|
|
}
|
|
}
|
|
|
|
std::optional<std::tuple<float, std::uint32_t>> mesh_collider::intersection(const math::transform<float>& mesh_transform, const geom::ray<float, 3>& ray) const
|
|
{
|
|
// Transform ray into mesh space
|
|
const auto inv_mesh_transform = math::inverse(mesh_transform);
|
|
const geom::ray<float, 3> mesh_space_ray =
|
|
{
|
|
inv_mesh_transform * ray.origin,
|
|
inv_mesh_transform.rotation * ray.direction
|
|
};
|
|
|
|
std::size_t box_hit_count = 0;
|
|
std::size_t triangle_hit_count = 0;
|
|
float nearest_face_distance = std::numeric_limits<float>::infinity();
|
|
std::uint32_t nearest_face_index;
|
|
|
|
m_bvh.visit
|
|
(
|
|
mesh_space_ray,
|
|
[&](std::uint32_t index)
|
|
{
|
|
++box_hit_count;
|
|
|
|
geom::brep_face* face = m_mesh->faces()[index];
|
|
auto loop = face->loops().begin();
|
|
const auto& a = (*m_vertex_positions)[loop->vertex()->index()];
|
|
const auto& b = (*m_vertex_positions)[(++loop)->vertex()->index()];
|
|
const auto& c = (*m_vertex_positions)[(++loop)->vertex()->index()];
|
|
|
|
if (auto intersection = geom::intersection(mesh_space_ray, a, b, c))
|
|
{
|
|
++triangle_hit_count;
|
|
|
|
float t = std::get<0>(*intersection);
|
|
if (t < nearest_face_distance)
|
|
{
|
|
nearest_face_distance = t;
|
|
nearest_face_index = index;
|
|
}
|
|
}
|
|
}
|
|
);
|
|
|
|
debug::log::info("mesh collider intersection test:\n\tboxes hit: {}\n\ttriangles hit: {}", box_hit_count, triangle_hit_count);
|
|
|
|
if (!triangle_hit_count)
|
|
{
|
|
return std::nullopt;
|
|
}
|
|
|
|
return std::make_tuple(nearest_face_distance, nearest_face_index);
|
|
}
|
|
|
|
} // namespace physics
|