psemek/libs/vecr/source/path.cpp

46 lines
979 B
C++

#include <psemek/vecr/path.hpp>
#include <psemek/math/interval.hpp>
#include <psemek/math/math.hpp>
namespace psemek::vecr
{
path closed(path path)
{
path.points.push_back(path.points.front());
return path;
}
sdf_sample sdf(path const & s, math::point<float, 2> const & p, bool closed)
{
sdf_sample result;
for (std::size_t i = 0; i + (closed ? 0 : 1) < s.points.size(); ++i)
{
auto const j = (i + 1) % s.points.size();
auto const e = s.points[j] - s.points[i];
auto const v = p - s.points[i];
auto const t = math::clamp(math::dot(v, e) / math::dot(e, e), {0.f, 1.f});
auto const q = v - t * e;
auto const l = math::length(q);
if (math::make_min(result.value, l))
{
if (l > 0.f)
result.gradient = q / l;
else
result.gradient = {0.f, 0.f};
}
}
return result;
}
math::box<float, 2> bbox(path const & s)
{
math::box<float, 2> result;
for (auto const & p : s.points)
result |= p;
return result;
}
}