maya additive and multiplicitive materials

noritsune

Hey guys -

Out of the box in Maya, it seems impossible to make a purely additive or multiplicitive material (such as one that might make light rays when applied to some planes).

a) am I wrong?

and b) if I'm not wrong, do any of you good people have workarounds, suggestions, or anything like that.

At work I get around this using proprietary shaders, but am faced with this problem on home/personal stuff.

Thanks!

Zergxes

Straight up there are add and multiply utility nodes that can be applied to any attribute of a shader in the hypershade.

There are a ton of Maya shaders on highend3d.com, I think all of them are free.

The glow attribute (under special effects tab in the shader) works roughly like what you are describing. You could also tweak with the ambient color. You could play around with light linking, and there are environment glow and environment fog attributes.

I guess the other question is do you want this to render in Maya or do you want it to play nice with other programs? For straight Maya stuff you can get lots of great answers on CGTalk.

Luck!

Daz

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At work I get around this using proprietary shaders, but am faced with this problem on home/personal stuff.

[/ QUOTE ]

Yeah, the big question here is shaders for what? Viewport, rendering in software, hardware, mental ray, some kind of engine? Either way, I'm not sure what's impossible about making an additive material, but I might be missing something.

noritsune

Sure let me try to clarify a bit. I want a maya shader that can make a texture like this show up like this in both maya software renderer and mental ray.

Seeing it correctly in viewport would also be great, though maybe getting a shader that does that is a separate solution? If there's a catch-all way to build your shader so that it will render correctly in hardware, software, mental ray, and most engines, then that's what I'm after.

It sounds (from the tone of your guys' posts) that this is an easy problem to tackle. I'm a bit noobish with the Hypershade beyond basic stuff, so maybe there's an quick solution there?

Thanks in advance!

ps: the shader I mentioned at work is entirely hw-based, so it does the job in viewport and in engine.

Daz

Ah ok. Well, exactly how important is it to you that what you get in a render is replicated in the viewport? 'cos (as Im sure you know) mayas viewport rendering capabilities just about suck.

I think that when I die I will still be angry about the fact that I need 3 entirely different shaders for normal mapping for rendering with either mray, software or viewport.

As for the effect you want to achieve, as with anything in maya, there really are umpteen different ways to go about it. Personally I would probably go for the simplest which might be (as Zergxes says) to simply play with the ambient colour channel or incandesence, and add a glow (under the special fx tab of your material) but you might want something a little more sophisticated I don't know.

Zergxes

Sorry if my answer was obtuse, I think your question sent me down memory lane. Hypershade is just nuts. Some people use it to rig with!

Yeah, I would do what Daz said or just dump it into the glow and turn off 'primary visibity' so you at least have something to start with. Glow responds to the lights in your scene.

Here's hoping that under the new flag they get Maya to play well with others.

Luck!

malcolm

Looks like you want a standard game additive which is different then a glow or incandescense or ambient. Not really sure how you get this in a render. The only way I know is to render out your sprites as seperate passes and comp them later as linear dodge in photoshop, we had to do this for the intro video of nba street3 with a tonne of render passes in after effects. Layer textures have the ability to multiply and add so perhaps there is a way to get it working on a material basis?

pyromania

If you make a lambert material thats completly transparent and plug the color from your file texture into the incandescence slot. You can get something like additive blending. Play around with the alpha gain on the file node, and add some glow on the lambert material for interesting effects.

noritsune

awesome guys! thanks for the responses. I'm looking forward to trying out some fo these methods soon. will perhaps post results...