public override IntersectionInfo Intersect(Ray ray)
{
IntersectionInfo info = new IntersectionInfo();
info.hit_object = this;
Vector dst = ray.Position - this.Position;
double b = dst.dot(ray.Direction);
double c = dst.dot(dst) - (radius * radius);
double d = b * b - c;
if (d > 0) // hit
{
info.is_hit = true;
info.dist = -b - (double)Math.Sqrt(d);
info.pos = ray.Position + ray.Direction * info.dist;
info.Color = this.Material.color;
info.normal = (info.pos - Position).normalize();
}
else
{
info.is_hit = false;
}
return(info);
}
public Color CalculateColor(Ray ray, Scene scene)
{
IntersectionInfo info = TestIntersection(ray, scene, null);
if (info.is_hit)
{
Color c = RayTrace(info, ray, scene, 0).toStandart();
return(c);
}
return(scene.backColor.toStandart());
}
public IntersectionInfo IntersectRay(Ray ray)
{
int hitCount = 0;
IntersectionInfo res = new IntersectionInfo();
res.dist = double.MaxValue;
foreach (IObject o in objects)
{
IntersectionInfo i = o.Intersect(ray);
if (i.is_hit && i.dist < res.dist && i.dist > 0)
{
res = i;
hitCount++;
}
}
return(res);
}
private Color_dbl RayTrace(IntersectionInfo info, Ray ray, Scene scene, int depth)
{
Color_dbl color = info.Color * scene.ambience;
foreach (Light l in scene.lights)
{
Vector v = (l.Position - info.pos).normalize(); // diffuse
double L = v.dot(info.normal);
if (L > 0.0f)
{
color += info.Color * l.Color * L;
}
if (depth < 5)
{
//shadows
IntersectionInfo shadow_info = new IntersectionInfo();
Ray toLight = new Ray(info.pos, v);
shadow_info = TestIntersection(toLight, scene, info.hit_object);
if (shadow_info.is_hit && shadow_info.hit_object != info.hit_object)
{
color *= 0.5;
}
//reflections
if (info.hit_object.Material.Reflection > 0)
{
Ray reflectionray = new Ray(info.pos, ray.Direction + info.normal * 2 * -info.normal.dot(ray.Direction));
IntersectionInfo ref_info = TestIntersection(reflectionray, scene, info.hit_object);
if (ref_info.is_hit && ref_info.dist > 0)
{
ref_info.Color = RayTrace(ref_info, reflectionray, scene, depth + 1);
}
else
{
ref_info.Color = scene.backColor;
}
color = color.Blend(ref_info.Color, info.hit_object.Material.Reflection);
}
}
}
color.Correct();
return(color);
}
private IntersectionInfo TestIntersection(Ray ray, Scene scene, IObject ignore)
{
int hitcount = 0;
IntersectionInfo best = new IntersectionInfo();
best.dist = double.MaxValue;
foreach (IObject o in scene.objects)
{
if (o == ignore)
{
continue;
}
IntersectionInfo info = o.Intersect(ray);
if (info.is_hit && info.dist < best.dist && info.dist >= 0)
{
best = info;
hitcount++;
}
}
best.hit_count = hitcount;
return(best);
}
public override IntersectionInfo Intersect(Ray ray)
{
IntersectionInfo info = new IntersectionInfo();
double Vd = Position.dot(ray.Direction);
if (Vd == 0)
{
return(info); // no intersection
}
double t = -(Position.dot(ray.Position) + D) / Vd;
if (t <= 0)
{
return(info);
}
info.hit_object = this;
info.is_hit = true;
info.pos = ray.Position + ray.Direction * t;
info.dist = t;
info.Color = Material.color;
info.normal = Position;
return(info);
}
