public static Tuple <bool, Vector3> RayPlaneIntersect(Vector3 origin, Vector3 ray, Vector3 point, Vector3 norm)
{
Vector3 w = point - origin;
float k = Vector3.Dot(w, norm) / Vector3.Dot(ray, norm);
Vector3 intersect = origin + k * ray;
Tuple <bool, Vector3> _return = new Tuple <bool, Vector3>(k >= 0.0f && k <= 1.0f, intersect);
return(_return);
}
public static List <Tuple <float, Vector3i> > RayBlockIntersection(Vector3 origin, Vector3 ray)
{
int[] sign = new int[]
{
(Convert.ToInt32(ray.X <= 0) * 2) - 1,
(Convert.ToInt32(ray.Y <= 0) * 2) - 1,
(Convert.ToInt32(ray.Z <= 0) * 2) - 1,
};
//Search 5x5x5 area to intersect, order by distance
//assume ray starts at 0,0,0 +- origin % 1
Vector3 rayStart = new Vector3(origin.X % 1.0f, origin.Y % 1.0f, origin.Z % 1.0f);
Vector3 positiveRay = new Vector3(ray.X * sign[0], ray.Y * sign[1], ray.Z * sign[2]);
List <Tuple <float, Vector3i> > intersections = new List <Tuple <float, Vector3i> >();
//Vector3i intersectPosition;
for (int _y = 0; _y < 6; _y++)
{
for (int _z = 0; _z < 6; _z++)
{
for (int _x = 0; _x < 6; _x++)
{
Tuple <bool, Vector3> _result = new Tuple <bool, Vector3>(false, new Vector3(0, 0, 0));
foreach (var tup in CubePointNorm)
{
_result = RayPlaneIntersect(rayStart, positiveRay, tup.Item1, tup.Item2);
if (!_result.Item1)
{
break;
}
}
//If we looped through all these we have a hit for this block!
//Recreate block position in worldorigin() +
Vector3i blockHit = new Vector3i(_x * sign[0] + (int)origin.X, _y * sign[1] + (int)origin.Y, _z * sign[2] + (int)origin.Z);
intersections.Add(Tuple.Create((origin - _result.Item2).LengthSquared, new Vector3i(_x, _y, _z)));
}
}
}
return(intersections);
}
