1.1 --- a/liberebus/src/geomobj.cc	Sat May 24 02:27:08 2014 +0300
     1.2 +++ b/liberebus/src/geomobj.cc	Sat May 24 06:12:57 2014 +0300
     1.3 @@ -18,6 +18,22 @@
     1.4  	return false;
     1.5  }
     1.6  
     1.7 +Vector3 GeomObject::calc_normal(const RayHit &hit) const
     1.8 +{
     1.9 +	// when you look at singularities, the singularities always look back at you :)
    1.10 +	return -(hit.world_ray.dir).normalized();
    1.11 +}
    1.12 +
    1.13 +Vector3 GeomObject::calc_tangent(const RayHit &hit) const
    1.14 +{
    1.15 +	return Vector3(1, 0, 0);	// whatever...
    1.16 +}
    1.17 +
    1.18 +Vector2 GeomObject::calc_texcoords(const RayHit &hit) const
    1.19 +{
    1.20 +	return Vector2();
    1.21 +}
    1.22 +
    1.23  // --- class Sphere ---
    1.24  
    1.25  bool Sphere::intersect(const Ray &ray, RayHit *hit) const
    1.26 @@ -47,6 +63,40 @@
    1.27  	return true;
    1.28  }
    1.29  
    1.30 +Vector3 Sphere::calc_normal(const RayHit &hit) const
    1.31 +{
    1.32 +	Vector3 pt = hit.world_ray.origin + hit.world_ray.dir * hit.dist;
    1.33 +	return pt.normalized();
    1.34 +}
    1.35 +
    1.36 +static inline Vector3 sphvec(float u, float v)
    1.37 +{
    1.38 +	float theta = u * M_PI * 2.0;
    1.39 +	float phi = v * M_PI;
    1.40 +
    1.41 +	return Vector3(sin(theta) * sin(phi), cos(phi), cos(theta) * sin(phi));
    1.42 +}
    1.43 +
    1.44 +Vector3 Sphere::calc_tangent(const RayHit &hit) const
    1.45 +{
    1.46 +	Vector2 uv = calc_texcoords(hit);
    1.47 +	Vector3 pnext = sphvec(uv.x + 0.05, 0.5);
    1.48 +	Vector3 pprev = sphvec(uv.y - 0.05, 0.5);
    1.49 +	return (pnext - pprev).normalized();
    1.50 +}
    1.51 +
    1.52 +Vector2 Sphere::calc_texcoords(const RayHit &hit) const
    1.53 +{
    1.54 +	Vector3 pt = hit.world_ray.origin + hit.world_ray.dir * hit.dist;
    1.55 +	pt.normalize();
    1.56 +
    1.57 +	float theta = atan2(pt.z, pt.x);
    1.58 +	float phi = acos(pt.y);
    1.59 +
    1.60 +	return Vector2(theta / M_PI + 0.5, phi / M_PI);
    1.61 +}
    1.62 +
    1.63 +
    1.64  // --- class Box ---
    1.65  
    1.66  bool Box::intersect(const Ray &ray, RayHit *hit) const