Nathan Kopp wrote in message <38b68a04@news.povray.org>...
>
>Gail Shaw <gsh### [at] monotixcoza> wrote...
>>
>> That would make my life SO much easier. Difficult to
>> implement though (Think of the following:
>> difference {
>>  union {
>>   sphere {
>>     <0,0.5,0>,1
>>     pigment {Red}
>>    }
>>    sphere {
>>     <0,-0.5,0>,1
>>     pigment {Blue}
>>    }
>>   }
>>   box {
>>    <0,-2,-2>,<2,2,2>
>>   }
>>  }
>>
>> What colour should the overlapped area of the spheres be?
>> Red, Blue or Purple?
>
>None of those.  The overlapped area should be the color of the box.  The
>surface in question could either belong to the box or to the whole CSG, but
>it couldn't belong to either (or both) of the spheres.
>
>If the box has not texture and you don't specify one for the CSG, then
you'd
>get the default texture.
>


I was replying to Peter's suggestion and illustrating a possible problem.

Peter Popov wrote :
>>>When performing a CGS difference or intersection, any object with a
>>>non-specified texture is assumed to have a black pigment and ambient
>>>0. I think a more reasonable behaviour would be to ignore its texture
>>>and use the texture of whatever object the intersection point is in.

Gail
*******************************************************************
* gsh### [at] monotixcoza              * ERROR: COFFEE.COM not found  *
* http://www.rucus.ru.ac.za/~gail/ * Insert cup and press any key *
*******************************************************************
* Definition of an upgrade: Take the old bugs out, put new ones in*
*******************************************************************

Post a reply to this message