Sorry if this is a repeated question,

How can I determine the front and back of a bicubic patch? I want to use an
interior_texture in combination with a uv mapped image and things are
looking like they are backwards. I get the impression that the +z direction
is the back. Is this right? I am actually using the patch which is in the
manual (in the bicubic patch tutorial).

-paul

--



===========================
Paul Daniel Jones
Ph.D. Candidate
The Pennsylvania State University
(814) 865-2090
===========================

Post a reply to this message

never mind!

paul



"paul jones" <pdj### [at] psuedu> wrote in message
news:3e38469b$1@news.povray.org...
> Sorry if this is a repeated question,
>
> How can I determine the front and back of a bicubic patch? I want to use
an
> interior_texture in combination with a uv mapped image and things are
> looking like they are backwards. I get the impression that the +z
direction
> is the back. Is this right? I am actually using the patch which is in the
> manual (in the bicubic patch tutorial).
>
> -paul
>
> --
>
>
>
> ===========================
> Paul Daniel Jones
> Ph.D. Candidate
> The Pennsylvania State University
> (814) 865-2090
> ===========================
>
>

Post a reply to this message

I don't know, but I suppose that it has something to do with the order
in which you give the control points. Reverse the order and you reverse
insideness.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

Post a reply to this message