//#endif
//#endfor instanced to '3Df'
#endregion
#region Triangle-Triangle Intersection
#endregion
#region Triangle-Ray Intersection
//#foreach instanced to '2Dd'
//#endfor instanced to '2Dd'
//#foreach instanced to '2Df'
//#endfor instanced to '2Df'
//#foreach instanced to '3Dd'
//#ifdef 3D
/// <summary>
/// Intersect triangle and ray, fast barycentric coordinate version.
/// </summary>
/// <param name="t">Triangle.</param>
/// <param name="Normal">Possibly precomputed normal.</param>
/// <param name="r">The ray.</param>
/// <param name="p">The output collision, valid if true is returned.</param>
/// <returns>Intersection result</returns>
public static bool Intersect(Triangle3d t, Ray3d r, double maxDist, out Vector3d p)
{
Vector3d Normal = t.Normal;
// We compute distance of ray of plane.
double d = -((r.Origin - t.A) * Normal) / (r.Direction * Normal);
// We exit quickly if intersection occurs behind ray, or if intersection does not
// exist.
if (d < 0.0 || d >= maxDist || double.IsNaN(d))
{
p = Vector3d.Zero;
return(false);
}
// We now compute the actual point on the plane.
p = r.Origin + d * r.Direction;
// We have to determine if point lies inside triangle. We do it using barycentric
// coordinates. We solve the system with two unknowns.
Vector2d uv = t.GetBarycentric(p);
// Is it inside.
if (Triangle3d.IsBaryCentricInside(uv))
{
return(true);
}
return(false);
}
//#endif
//#endfor instanced to '3Df'
#endregion
#region Triangle-Line Intersection
//#foreach instanced to '3Dd'
//#ifdef 3D
/// <summary>
/// Triangle-Line intersection helper (only 3D version).
/// </summary>
/// <param name="t">The triangle.</param>
/// <param name="r">The line.</param>
/// <param name="p">Point of intersection.</param>
/// <returns>Does intersection exist.</returns>
private static bool Intersect(Triangle3d t, Line3d r, out Vector3d p)
{
Vector3d Normal = t.Normal;
// We compute distance of line of plane.
double d = -((r.A - t.A) * Normal) / (r.Direction * Normal);
// We now compute the actual point on the plane.
p = r.A + d * r.Direction;
// We have to determine if point lies inside triangle. We do it using barycentric
// coordinates. We solve the system with two unknowns.
Vector2d uv = t.GetBarycentric(p);
// Is it inside.
return(Triangle3d.IsBaryCentricInside(uv));
}
//#endfor instanced to '3Df'
#endregion
#region LineSeg-Triangle Intersection
//#foreach instanced to '3Dd'
//#ifdef 3D
/// <summary>
/// A line-triangle intersection.
/// </summary>
/// <remarks>Only point is returned. In case of line segment lying on top of triangle, one
/// point is only returned.</remarks>
/// <param name="line">The line segment</param>
/// <param name="triangle">The triangle</param>
/// <param name="point">The intersection point.</param>
/// <returns>Does intersection occur</returns>
private static bool Intersect(LineSegment3d line, Triangle3d triangle, out Vector3d point)
{
// We compute distance of ray of plane.
double d = -((line.A - triangle.A) * triangle.Normal) / (line.Direction * triangle.Normal);
// We exit quickly if intersection does not occur on line.
if (d < 0.0 || d > 1.0)
{
point = Vector3d.Zero;
return(false);
}
// We now compute the actual point on the plane.
point = line.A + d * line.Direction;
// We have to determine if point lies inside triangle. We do it using barycentric
// coordinates. We solve the system with two unknowns.
Vector2d uv = triangle.GetBarycentric(point);
// Is it inside.
return(Triangle3d.IsBaryCentricInside(uv));
}
