On 01/06/2014 at 15:50, xxxxxxxx wrote:
I'm creating a shader and I need to know what face is being rendered (the index of the face).
I already have the object that is being rendered (the shader works in junction with a tag and it is easy to get the object that is using the tag) and the object must ALWAYS be polygonal.
So, inside my shader I already have the object and I'm sure it is polygonal.
But I want to know how to be able to find what face is being rendered.
I tried using something like this:
def Output(self, sh, cd) :
op=None
the_tag=sh[VMAP_OBJECT]
if the_tag is not None:
op=the_tag.GetObject()
op_type=op.GetType()
if op_type != c4d.Opolygon: return c4d.Vector(0) # return black if it isn't a polygonal object
if cd.vd: #if shader is computated in 3d space
volumedata=cd.vd
ray=volumedata.ray
collision=c4d.utils.GeRayCollider()
collision.Init(op,False)
hit=collision.Intersect(ray.p,ray.v,volumedata.dist+1.0,False)
if hit is True:
print collision.GetIntersection(0)["face_id"]
return c4d.Vector(1.0,0,.5)
else: #if shader is computated in 2d space
return c4d.Vector(0.0,1.0,0.0)
But it is not detecting any intersection.
Am I doing it wrong?