rednering elements to alpha

Ruz

when rendering to texture, I am using multiple objects baked on to a low poly mesh and would like have an alpha for each element without separating the high res mesh. ie a high res torso might have 12 different elements , but they are all attached.
I am renderig out a diffuse, so can use the magic wand to select the different colours in pshop, but would like the cleaner alphas rendered out also.
is there an easy way to do this or am I missing the point and approaching it wrong?

Ruz

problem is luke if you select each colour with the magic wand you get horrible ragged edges. is there a better way to select your colours and get clean edges like the alpha channel does?
select by colour range still gives me slightly weird edges

Mark Dygert

What about color select? I think it would suffer from some of the same problems as the wand... humm.

OR what about output it with alpha, hold shift and click the alpha channel to get better selection? Remember you can toss a bunch of alpha channels in the channels menu and use that method to house various selections. The trick is knowing the file format you save/export to and how it will handle all the extra alpha channels. I think most formats ignore all but the first one?

Ruz

yeah the thing is Mark I will then have to separate all my high poly objects, which is doable , but a bit inconvenient as some of my meshes have a lot of subobjects
BTW I recently discovered 'paste in place' in photoshop. what a godsend:)



Mark did you mean copy the diffuse in to the alpha channel, then shift select to gte a clean slection. perhaps I misunderstood what you were getting at

edit
refine edges really helps. I think I can just about manage to get what I am after using magic wand+refine edges

Mark Dygert

ToTex has a render material ID feature, I haven't used it so I'm not sure what it gives you, but if its able to render out a single material ID or send each ID to a separate file, without much fuss it might be worth downloading.
http://www.scriptspot.com/3ds-max/scripts/totex-render-to-texture

Also, it requires some work and it might already have been scripted, but if you separate out each material ID to its own UV channel you can select each UV channel and render out just that? It's too bad RTT doesn't have a way to selectively render out material ID's... or if it does I haven't ever found it.

rollin

Ruz wrote: »

BTW I recently discovered 'paste in place' in photoshop. what a godsend:)

lol me too ruz

Mark Dygert

I didn't know about paste in place, I'll have to look that up.

I would hold down ctrl+alt and drag one layer from a file into another and it will land in the correct position in the new file, provided you don't have anything selected which I think might do the same thing?

Ruz

yup its the same thing Mark. I used to do that in pshop 7, but it didn't always work
ha rollin, I could have kicked myself
anyway I will try 'totex' - cheers for the link

edit - yeah that script is fantastic, did just what i wanted and knocks out nice AO maps too