mpri-graphics-project/spheroid.cpp
Théophile Bastian 7b374c70ae Surfaces now provide a location hint
This is supposed to be a point in space close to the surface
2018-02-13 18:42:15 +01:00

81 lines
2 KiB
C++

/**
* Implementation of a spheroid
**/
#include "spheroid.hpp"
#include <iostream>
Spheroid::Spheroid(const Point& _center, double _min_p, double _p, double _q) :
ImplicitSurface(_center), normal_vector(Point(0,0,1)), min_p(_min_p),
init_p(_p), p(_p), q(_q), stiffness(0)
{
_compute_volume();
}
void Spheroid::_compute_volume() {
V = (4./3.) * PI * p * q * q;
}
void Spheroid::update_radius() {
q = sqrt((3./4.) * V / PI / p);
}
void Spheroid::update_height() {
q = (3./4.) * V / PI / (p*p);
}
void Spheroid::update_center_pos(Point& _center) {
center = _center;
}
void Spheroid::check_horizontal_plan_collision(double height) {
if (((center.y - p) <= height) || (p < init_p)) {
p = fmin(init_p, center.y-height);
update_radius();
}
}
void Spheroid::check_vertical_plan_collision(double& abscissa) {
if (center.x <= abscissa) {
if ((center.x + q) >= abscissa) {
q = abscissa - center.x;
update_height();
}
} else {
if ((center.x - q) <= abscissa) {
q = center.x - abscissa;
update_height();
}
}
}
Cuboid Spheroid::max_bounding_box() const {
double max_radius = sqrt((3./4.) * V / PI / min_p);
double max_height = init_p;
Point _bd1(max_radius, max_height, max_radius);
Point _bd2(-max_radius, -max_height, -max_radius);
return Cuboid(_bd1, _bd2);
}
void Spheroid::check_perlin_collision(PerlinNoise perlin) {
double height = perlin.noise(center.x, center.z);
if ((center.y - p) <= height) {
p = fmin(init_p, center.z- height );
normal_vector = perlin.normal_vector(center.x, center.z);
update_radius();
}
}
double Spheroid::operator() (double _x, double _y, double _z) const {
return (pow(_x, 2) / pow(q, 2)
+ pow(_y, 2) / pow(p, 2)
+ pow(_z, 2) / pow(q, 2) -1);
}
Point Spheroid::location_hint() const {
return Point(0, p, 0);
}