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Add crude point-convex body distance to cg

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This commit is contained in:
Nikita Lisitsa 2024-03-14 08:42:58 +03:00
parent d179ef65a2
commit 47d3156c57
1 changed files with 70 additions and 0 deletions
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libs/cg/include/psemek/cg/convex/distance.hpp Normal file
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#pragma once
#include <psemek/cg/body/body.hpp>
#include <psemek/geom/interval.hpp>
#include <psemek/geom/math.hpp>
namespace psemek::cg
{
namespace detail
{
template <typename Body, typename T>
T distance_fast_2d(Body const & b, geom::point<T, 2> const & p)
{
T result = geom::limits<T>::min();
auto const & vs = vertices(b);
for (auto const & e : edges(b))
{
auto n = geom::ort(geom::normalized(vs[e[0]] - vs[e[1]]));
geom::make_max(result, geom::dot(n, p - vs[e[0]]));
}
return result;
}
template <typename Body, typename T>
T distance_fast_3d(Body const & b, geom::point<T, 3> const & p)
{
T result = geom::limits<T>::min();
auto const & vs = vertices(b);
for (auto const & f : faces(b))
{
auto n = geom::normal(vs[f[0]], vs[f[1]], vs[f[2]]);
geom::make_max(result, geom::dot(n, p - vs[f[0]]));
}
return result;
}
}
// Returns an upper bound of the distance between b and p
// using only edge/face normals
template <typename Body, typename Point>
auto distance_fast(Body const & b, Point const & p)
{
constexpr auto dim = dimension<Body>;
static_assert(dim == 2 || dim == 3);
if constexpr (dim == 2)
{
return detail::distance_fast_2d(b, p);
}
else if constexpr (dim == 3)
{
return detail::distance_fast_3d(b, p);
}
else
{
return;
}
}
}