Mike Williams wrote:
> Wasn't it Timwi who wrote:
>>
>> Try rendering this with use_iso set to 0 and then with it set to 1. I 
>> would have thought the two should produce pretty much the same result, 
>> since the isosurface is equivalent to the cylinder.
>>
>> But the result I get is this: with the cylinder everything works as 
>> expected, but with the isosurface, the inside of the object is 
>> completely black, even though there is a light source right next to it.
> 
> There's two things going on. One of them is you doing something wrong 
> and one could possibly be a bug.
> 
> When you perform CSG with an isosurface you must either set max_trace 
> appropriately or use all_intersections.

Thanks a lot... although it raises the question: why is that not the 
default? Why is the default something that is, apparently, broken by 
definition (because it doesn't calculate all intersections it needs to 
generate the correct result)?

> That still leaves the bottom of the hole darker when you use the 
> isosurface.

Yeah. Should I report that as a bug?

In my case, I worked around it by having the isosurface cut a little bit 
deeper and then filling up the bottom of the hole with another box... 
but ideally, of course, I shouldn't have to do that.

Thanks
Timwi

Post a reply to this message