fart/util/Transform.cc

85 lines
1.8 KiB
C++

#include "Transform.h"
#include <math.h>
Transform::Transform()
{
}
Transform Transform::getInverse()
{
Transform inv;
inv.m_matrix = m_matrix.getInverse();
return inv;
}
void Transform::translate(double x, double y, double z)
{
Matrix t = Matrix::identity();
t[0][3] = x;
t[1][3] = y;
t[2][3] = z;
m_matrix *= t;
}
void Transform::rotate(double angle, double xv, double yv, double zv)
{
/* formula from http://en.wikipedia.org/wiki/Rotation_matrix */
Vector l(xv, yv, zv);
l.normalize();
double c = cos(M_PI * angle / 180.0);
double s = sin(M_PI * angle / 180.0);
double lx2 = l[0] * l[0];
double ly2 = l[1] * l[1];
double lz2 = l[2] * l[2];
Matrix t = Matrix::identity();
t[0][0] = lx2 + (1 - lx2) * c;
t[0][1] = l[0] * l[1] * (1 - c) - l[2] * s;
t[0][2] = l[0] * l[2] * (1 - c) + l[1] * s;
t[1][0] = l[0] * l[1] * (1 - c) + l[2] * s;
t[1][1] = ly2 + (1 - ly2) * c;
t[1][2] = l[1] * l[2] * (1 - c) - l[0] * s;
t[2][0] = l[0] * l[2] * (1 - c) - l[1] * s;
t[2][1] = l[1] * l[2] * (1 - c) + l[0] * s;
t[2][2] = lz2 + (1 - lz2) * c;
m_matrix *= t;
}
void Transform::scale(double xs, double ys, double zs)
{
Matrix t = Matrix::identity();
t[0][0] = xs;
t[1][1] = ys;
t[2][2] = zs;
m_matrix *= t;
}
Vector Transform::transform_point(const Vector & v)
{
return m_matrix * v;
}
Vector Transform::transform_direction(const Vector & v)
{
return m_matrix % v;
}
Vector Transform::transform_normal(const Vector & v)
{
return (m_matrix % v).normalize();
}
Ray Transform::transform_ray(const Ray & r)
{
Vector newPosition = m_matrix * r.getOrigin();
Vector newDirection = m_matrix % r.getDirection();
Ray res(newPosition, newDirection);
return res;
}