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jasonazure
02-04-2010, 12:50 PM
Hi Community

Can someone please confirm that vertex normals don't render correctly with the classic camera in version 9.6.

I've imported some Polytrans files (originally Pro/E) into Lightwave that all use vertex normals and even though the polygons are pretty rough, the models look and render lovely and smooth with the Perspective camera.

I just decided to try the Classic Camera to see if I could get faster rendering times and all the elements using vertex normals render as though they are inside-out / very dark!

If this is the way it is, then that's fine, I just wanted to make sure I'm not doing something wrong!

Thanks

Jason

jasonazure
02-05-2010, 02:31 AM
Hasn't anybody experienced this?

Sensei
02-05-2010, 02:38 AM
Classic fail, Perspective ok? no.. Never saw such situation.. If it fails it's usually in both.. ;)
Because of source object not right and/or LW built-in OBJ importer is broken, or both. If you have TrueOBJImport, you can try instead of LW built-in.
http://www.newtek.com/forums/showthread.php?t=60529&highlight=trueobjimport

lansd
02-05-2010, 07:06 AM
I've imported some PolyTrans files (originally Pro/E) into Lightwave that all use vertex normals and even though the polygons are pretty rough, the models look and render lovely and smooth with the Perspective camera.

I won't comment on this directly, but keep in mind that when I export to LW 9.6 I can and do embed the real vertex normals of the ProE data. From 1993 through to 1997 I could only output one smoothing angle per material and no original vertex normals. LW users are now generally starting to use this "new" 9.6 method to import the proper vertex normals as of 2009 and later (it always takes people time to migrate to new concepts). I could only guess that the classic camera may still only use the original smoothing groups and not the new MODO/LW9.6 "vert_normals" chunk data.

Also, as per my other posting I made about 3 months ago, you need to make sure to get my 2009/2010 release which allows you to toggle between the incorrect MODO "vert_normals" chunk and the proper LW 9.6 "vert_normals" chunk. MODO had defined this new .lwo file chunk in 2007, which I implemented, but I found out they were using the RHCS and not LHCS for their normals definition. I modified our LW exporter and importer to provide freedom of choice in this situation. The toggle will allow the vertex normals to be inverted from RHCS to LHCS, as they should be.

jasonazure
02-05-2010, 07:23 AM
Hi Robert

Thanks for the heads up. I've actually been using the OBJ route to get my models into Lightwave to test this, and it seems pretty solid in 9.6 with the perspective camera.

I'm probably going to upgrade my copy of PolyTrans now anyway as I've just won a contract to animate loads of diesel engines, and all the files will be coming to me in .prt and .asm format, so I'm really going to need the lws/lwo export method!

Just wish Lightwave had this years ago. If you knew how many weeks I've spent in the past splitting up and stitching meshes to get them to render acceptably!

lansd
02-05-2010, 07:33 AM
Just wish Lightwave had this years ago. If you knew how many weeks I've spent in the past splitting up and stitching meshes to get them to render acceptably!

The story I repeat often is that I had been asking the original Lightwave layout program developer to add vertex normals actively from 1997 onwards. I really wanted it badly in 1997. I then had to endure 12 years of explaining "smoothing groups" to all of my CAD to LW users almost daily -- it's a core aspect of my "CAD FAQs" which come with the download of our software. I was very happy when the same LW developers finally defined the "vert_normals" chunk for MODO in 2007, and then LW 9.6 finally got it implemented around Jan 2009.

Historically, all "modern and expensive" animation systems were written around 1987 +- 2 years. At that time "smoothing groups" were all the norm and rage, from a lack of understanding of how to properly write 3D software. Only Alias got it right with the release of Alias 3.0 around 1988, and then Softimage-3D a few years later. 3ds Max is based on CAD-3D of the Atari ST realm and it still continues to use smoothing groups. Ditto for trueSpace, Maya and Cinema-4D. For Maya 2.51, I finally had Alias add in vertex normals, but now imports take 10x longer due to that code change (Maya still uses smoothing groups as well). It is always interesting to see how today's animation software is still bogged down with decisions made in the mid 80's. At least LW finally has the greatest "missing piece" of the geometry puzzle.