CompuServe Messages

Bones in LWPro

    09-Oct-94 01:44:19
Sb: #92105-Bones in LWPro
Fm: Wayne Cole 76370,621
To: John Gross 71740,2357
John, This is the old glass table problem I sent you the files for a while back. The glass top is 1.5 inches thick. I have tried modelling that as a simple box, with only outward facing polygons, (normals going into the air) duping and flipping a copy to get a surface normals in each direction, (going into the glass and into the air). I kept the simple approach. Now, the problem is that with a 1.5 IR, the distortion is orders of magnitude off from what I see looking at the table in real life that I modelled. (I ven measured my viewing position and set the camera accordingly during one "trial". In order to get the rendered fram to look like "real-life" I had to drop the glass IR to 1.01. And it appears the same in every version of LW I've owned up to 3.5 (haven't tried it in 3.5 yet. Oops – that's not true – I didn't make the model until the first "free" update to those who orignally paid like $1395 list for the Toaster, but before 2.0. Now regarding the bugs. How is air handled? The legs are sitting in space (I have no model air in the scene). Is empty space RI 1.0? Is it subject to the ignored 1.0 medium problem you mentioned? (Sounds stupid, but I have obviously missed something as all LW Versions have given the same erroneous result.) It sounds like, from your comment on 3.5 that I have to create an "air box" around the glass table top with a pocket in it, faces not quite touching, and face its normals into that glass, giving it an IR of 1.001 and transparency 100%. Let me try that… Holy Mackerel!!! That was it!! (LW 3.1 – My 3.5 is on another machine and the net is not up at the moment. I'll try it there later). Sheesh! It never dawned on me that I would have to model the air as well. Stupid!! I just sorta assumed 'virtual reality' came with it pre-installed! Man!! So dad-burned obvious and I've spent years 'in the dark'. &*^%$#@!! Anyway, that leaves me with an enhancement request. Why not have a "Universe" setting that defines your empty space with IR being one element. That way whether its ocean, deep space, a liquid Nitogen atmosphere or inside a glass paperweight you can set the objects' environment to get the correct response for light passing through the objects. wmc – via Autopilot!