bool triangle::intersect(ray const& Ray, intersection& Intersection) const
{
glm::vec3 w = Ray.get_position() - A;
glm::vec3 u = -(B - A);
glm::vec3 v = -(C - A);
float D = glm::dot(glm::cross(u, v), Ray.get_direction());
float a = -glm::dot(glm::cross(w, v), Ray.get_direction()) / D;
float b = -glm::dot(glm::cross(u, w), Ray.get_direction()) / D;
float t = glm::dot(glm::cross(u, v), w) / D;
if(a > 0.0f && b > 0.0f && a + b < 1.0)
return true;
return false;
}
bool plane::intersect(ray const& Ray, intersection& Intersection) const
{
bool hit = false;
if(glm::abs(Ray.get_direction().z) > 0.0f)
{
float t = -Ray.get_position().z / Ray.get_direction().z;
if(t > glm::epsilon<float>() * 100.f)
{
Intersection.set_local_position(Ray.get_position() + Ray.get_direction() * t);
hit = true;
}
}
return hit;
}
bool bounding_box::intersects(const ray & ray, intersection_data & out) const
{
float distance_max = std::numeric_limits<float>::max();
const box & aabb = bounding_box::get_box();
const point & min = aabb.get_min();
const point & max = aabb.get_max();
const float epsilon = 0.01f;
for (int i = 0; i < 3; i++)
{
if (std::abs(ray.get_direction()[i]) < epsilon)
{
if (ray.get_origin()[i] < min[i] || ray.get_origin()[i] > max[i])
return false;
}
else
{
float ood = 1.0f / ray.get_direction()[i];
float t1 = (min[i] - ray.get_origin()[i]) * ood;
float t2 = (max[i] - ray.get_origin()[i]) * ood;
if (t1 > t2) std::swap(t1, t2);
if (t1 > out.distance) out.distance = t1;
if (t2 > distance_max) distance_max = t2;
if (out.distance > distance_max)
return false;
}
}
out.coordinates = ray.get_origin() + float3(ray.get_direction());
out.coordinates = out.coordinates * out.distance;
return true;
}
bool bounding_sphere::intersects(const ray & ray, intersection_data & out) const
{
point m = ray.get_origin() - origin;
point b = point(XMVector3Dot(m, ray.get_direction()));
point c = point(XMVector3Dot(m, m)) - std::pow(get_radius(), 2);
if (c > 0.f && b > 0.f)
return false;
float disc = std::pow(b[axis::x], 2) - c[axis::x];
if (disc < 0.f)
return false;
out.distance = -b[axis::x] - std::sqrt(disc);
if (out.distance < 0.f)
out.distance = 0.f;
out.coordinates = ray.get_origin() + point(out.distance) * float3(ray.get_direction());
return true;
}
bool bounding_sphere::intersects(const ray & ray) const
{
point m = ray.get_origin() - origin;
point c = point(XMVector3Dot(m, m)) - std::pow(get_radius(), 2);
if (c <= 0.f)
return true;
point b = XMVector3Dot(m, ray.get_direction());
if (b > 0.f)
return false;
float disc = std::pow(b[axis::x], 2) - c[axis::x];
return disc >= 0.f;
}