Re: Bug in E3Triangle_InterpolateHit

[Roger H. <rog...@mi...>]

On Tuesday, August 3, 2004, at 11:22  pm, Dair Grant wrote:

>
>> Our tester has given my changes to E3Triangle_InterpolateHit a few
>> hours testing in Microspot Modeller and it seems to be pretty solid
>> now. We will be making the golden master of Modeller this week.
>>
>> Any objections to me checking in the changes to Quesa?
>
> This solution would be a step forward for the short term anyway, as 
> it'd
> mean we would return the correct result if you're just doing a
> rotation/translation/uniform scale as your transform.
>
> So I'd go with that for now (unless you want to do the general fix 
> too),
> but could you log a bug indicating that this isn't going to be 100%
> correct?


Perhaps you missed one of my e-mails. I think it is the general fix we
were testing, it certainly was much better than simply multiplying by
local to world. I have checked it in as it is definitely much better 
than
before. I used some code I wrote for my renderer for getting the right
normal for the lighting calculations.

I presume the interactive renderer does something similar otherwise
the lighting would look a little weird as a surface in world coordinates
gives different lighting to a parallel surface in local coordinates 
with a
rotation and non uniform scale transform applied.

Roger.