// Distance to Plane(Point?)? WTF IS THIS!?
func d2p(tmat mathgl.Mat4, point, ray mathgl.Vec3) float32 {
var mat mathgl.Mat4
mat.Assign(&tmat)
var sub mathgl.Vec3
sub.X = mat[12]
sub.Y = mat[13]
sub.Z = mat[14]
mat[12], mat[13], mat[14] = 0, 0, 0
point.Subtract(&sub)
point.Scale(-1)
ray.Normalize()
dist := point.Dot(mat.GetForwardVec3())
var forward mathgl.Vec3
forward.Assign(mat.GetForwardVec3())
cos := float64(forward.Dot(&ray))
return dist / float32(cos)
}
