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Added regular polygons and started implementation of arbitrary (general)

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polygons
This commit is contained in:
Karma Riuk 2023-04-25 12:01:51 +02:00
parent 4a7e5834d3
commit bf9545a7a0
2 changed files with 35 additions and 0 deletions
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31
polygon_generator.cc
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@ -46,3 +46,34 @@ polygon poly_generate::triangle(
one_over_36 * mass * base * std::pow(height, 3),
mass};
}
polygon poly_generate::regular(double radius, uint n_sides, double mass) {
assert(n_sides > 2);
std::vector<vec2d> points;
points.reserve(n_sides);
double theta = 2 * M_PI / n_sides;
for (uint i = 0; i < n_sides; i++)
points.push_back({radius * cos(i * theta), radius * sin(i * theta)});
double l = vec2d::norm(points[1] - points[0]);
double sin_, cos_;
sincos(M_PI / n_sides, &sin_, &cos_);
double cot = cos_ / sin_;
double inertia = mass * l * l / 24 * (1 + 3 * cot * cot);
return polygon{{0, 0}, 0, points, inertia, mass};
}
static double intertia_of_polygon_subtriangle(
vec2d& centroid, vec2d& p1, vec2d& p2) {
double base, height;
if (vec2d::norm(p1 - centroid) > vec2d::norm(p2 - centroid))
base = vec2d::norm(p1 - centroid);
}
polygon poly_generate::general(std::vector<vec2d>& points, double mass) {
double intertia = 0;
return polygon{{0, 0}, 0, points, intertia, mass};
}

4
polygon_generator.h
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@ -16,5 +16,9 @@ namespace poly_generate {
polygon triangle(double side1, double side2, double angle, double mass = 1);
polygon regular(double radius, uint n_sides, double mass = 1);
polygon general(std::vector<vec2d>& points, double mass = 1);
}; // namespace poly_generate
#endif