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benthroop
02-07-2002, 03:06 AM
Hey All,

Just curious as to different people's ideas on the best way to vertex light worlds. We use Max, so the obvious method is placing Max lights and using the Assign to Vertex Colors utility. This has the obvious limitations of being direct illumination only, and also not casting shadows properly. As I understand it, the utility won't cast shadows within a single object, it will only cast from one object to another... so if you're dealing with a single mesh, you might as well forget about shadows.

I've checked out Luminaire and it seems like it's _this_ close to being the perfect tool. Is anyone else using it for vertex lighting? I've talked to the author and he's a super nice guy, but apparently his day job has taken him away from the project. Regardless, it does nice radiosity lighting. Getting that data onto the actual verts seems to be hit and miss... if anyone has a surefire technique for using this tool I'd love to hear about it.

bit

jakehh
02-07-2002, 03:39 AM
have you tried final render?...you can create light maps and bake vertex colors into the texure..
-j

The Magic Pen
02-07-2002, 04:55 AM
Light maps are a much better result but it uses a lot of memory if you have it all over the place. We use luminare and it is about the best that is out there that I have found anyways never tried that othr thing though ..but baking the lighting into the texture sounds good if you dont have to reuse the texture over and over again. I am not a technical artist by any means does someone know how they did the lighting in Luigi's mansion ?? That was some damn good lighting !!

jakehh
02-07-2002, 05:00 AM
you can do it by matreial i.d. and you can also crak out the light info sepratly.....and later combine the texture and light map if needed...yeah in our game we use lightmaps sparingly...but some of the results are fantastic..

benthroop
02-07-2002, 07:10 AM
Well lightmaps are great but they eat up VRAM... vertex coloring is essentially free when it is precalculated, so for many game engines it is a wise choice.

I know that Maya has some vertex lighting tools but I'm not familiar with them. Anyone know how they compare to Max's?

bit

bclark
02-07-2002, 10:49 PM
For our vertex lighting in max we had a programer make a utility for us that is a faster more acureate version of the max assign vertex colors. We would place our lights and then bake in the colors and shadows for a rough pass.

Then using a custom maxscript that uses soft selection to affect vertex color falloff and let us do additive vertex coloring we fine tune the lighting by hand.

Light maps are used to some extent but not as much as vert lighting.

later,
Brad

subagio
02-08-2002, 05:11 AM
We're doing a whole hodgepodge of vc, pregenerated lightmaps, and realtime lightmaps in this game. Almost everything needs vertex colors though, so we generally start by cutting in our shadow geometry, giving everything a quick once over with the assign tool, then I have a small script I coded that lets us do a hsv/rgb style control on selected vertices with falloff. This gets us close enough :)

--C

jakehh
02-08-2002, 05:29 AM
do you have any screen shots you can show...thats shows the results ?..id be interested in checking it out...
-j

benthroop
02-09-2002, 01:12 AM
chris,

any chance you could make that script public? there arent any vertex color adjustment scripts out there that support falloff. if it's company property, though, i completely understand.

ben

subagio
02-09-2002, 02:22 PM
Sorry. I was waiting to hear from the big wigs, but at this point it's no material out the company at all, so no wip screenshots, and definitely no scripts :( Life was simpler when I worked for myself... sigh.

It wasn't too hard though. Maxscript support is decent (though it could use more work in the vertex data handling dept.). I've managed to code quite a few tools in that category. The main ones are the rgb/hsv with falloff tool and a lighting tool that's similar to assign VCs, but takes as it's input the angle of the main light we use in game (the 'sun') as default, a bunch of color swatches and options and calculates a lighting model that has clamped overbright values, indirect, ambient and shadowing. Get your tools boys to do the same.

--C

CADster
02-13-2002, 12:56 AM
I do it the old school way ...

I made a tutorial here -
http://www.rvcc.cadster.com/tutorials/vertex/vertex.html
for shading cars .


CADster

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