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ackees
03-15-2007, 01:52 PM
Is there a way to texture an object with the object not visible but the texture on the object visible?
Thanks

Lewis
03-15-2007, 03:03 PM
Can you explain it better ? I don't understand how would you see it if is not visible :)? You always can make complete textured man with cloth and then dissolve "man" layer and leave cloth visible or even model just cloth and don't bother with invisible :).

toby
03-15-2007, 03:43 PM
Make the part with the texture a different surface in modeler, then make the other surface transparent. Or make a texture map for the transparency channel that's the opposite of the texture you want visible.

stib
03-15-2007, 10:33 PM
You can just render out the diffraction, without any reflection specularity or diffuse. So set up a surface with an index of refraction > 1, and no diffuse, 100% transparent, 0 spec and reflection. render with ray trace refraction turned on. Makes a good invisble surface.

ackees
03-16-2007, 03:49 AM
I don't know about this there is something weird about it.

The object becomes the texture when you add texture,
and the alpha seems to tell the object where there is no texture so then you see object and not texture in those places. But if you say you do not want to see the object you also do not see the texture (light properties - exclude).

A clip map does it (make an alpha of the areas to be clipped from the model leaving the parts with texture intact) but it's very harsh (works on 50, 50) chops everything like late 70's 3D.

Lewis,
if I have a complex texture over the object (a torn garment) I would have to make an exact replica of the object with all the tears etc. but then the client walks in and says "Oh, lets move that that over to the other side because the logo goes here - you would have to go and remodel instead of simply doing a quick paint job in Photoshop.

Toby, same problem as above.

Stib,
I cannot use ray tracing, it's an animation.

Something like this should be a simple button click.
I am sure I have missed a trick somewhere because it's too simple to have been left out of LW.

stib
03-16-2007, 04:41 AM
[QUOTE=ackees
Stib,
I cannot use ray tracing, it's an animation.
[/QUOTE]
huh? I do plenty of animations with ray tracing, (sometimes even with reflection, transparency shadows AND difraction..)*

Anyway, are you trying to make a lacy texture? Why not just use transparency. If your're using layers, just use an image on your transparency channel. For that it needs to be white where you want it to be transparent. Now to stop the material looking like glass or clear plastic over the transparent bis you also have to turn off the specular and relfections in the transparent bits. Copy your transparency image to he specular and reflection channel, but heck the box that says invert, because you want no specularity on the transparent areas, ie they need to be black.

A great way to do this is just to choose "copy selected layers" and paste to another property in the layers part of the texture editor, or even better you can pipe the alpha channel from an image node to the speculr and reflection channels.if you're using nodes.

If that doesn't answer your question, maybe you need to think about what it actually is you want to see, and how to explain it to those of us who don't know the project.
HTH
-stib
*I'd probably split it into passes though

mattclary
03-16-2007, 07:31 AM
huh?

LMAO! My thoughts exactly. :thumbsup:

Surrealist.
03-16-2007, 11:52 AM
I think what you want is simply a texture what has holes in it from what I can understand. You don't want it glassy or refractive, all you want is to make it look like there is a cloth around the object that has volume - like the invisible man. Stib pointed out using and image map on the transparency channel. You can do this with layers or with nodes.

But the point is, all you need to do is have an apha image that maches the logo - black and white. It can be gray scale and this way you can have it be less sharp - not like the clip map. . You use this to create a transparency map so that whatever is not the logo or whatever it is, will be "invisible".

If you want it to move over the surface of the object. An easy way to do that is use the "reference object" feature. this is a good way to use a null in real time to position the texture. You can do it right in Layout without rendering as the texture will show up. This way you could move it around the object and test different positons.

Now to really do it right you may have to create a UV map - that's anbother story - but you will loose the reference null option.

Sounds like an interesting porject. Let us know how it comes out.

ackees
03-16-2007, 04:09 PM
Stib, Surrealist,
The transparency map does work fine on UV textures (texture UV then alpha UV to transparency - no nodes for backwards etc), it seems a little heavy on processing though considering the simplicity, LW seems to run over the render twice so everything with transparency takes twice as long, logically it should take half the time.
Thanks all

toby
03-16-2007, 09:56 PM
LW seems to run over the render twice so everything with transparency takes twice as long, logically it should take half the time.

How will the LW render engine know it's transparent if it doesn't render it? :) And rendering everything behind it adds time too

Stooch
03-16-2007, 10:15 PM
i textured an invisible man before, i would show you but he is invisible...

eagleeyed
03-17-2007, 12:37 AM
i textured an invisible man before, i would show you but he is invisible...
Ha Ha Ha, You made a funny.

Seriously, that cracked me up.

ackees
03-17-2007, 09:37 AM
i textured an invisible man before, i would show you but he is invisible...

I've seen him!
He's got texture all over him but invisible otherwise.
Got caught in a bank job I herd, he thought no one would see him but forgot about the texture, he got caught texture handed. Hollywood has bought the rights.

Sensei
03-17-2007, 09:06 PM
Stib, Surrealist,
The transparency map does work fine on UV textures (texture UV then alpha UV to transparency - no nodes for backwards etc), it seems a little heavy on processing though considering the simplicity, LW seems to run over the render twice so everything with transparency takes twice as long, logically it should take half the time.
Thanks all

You must understand that ray-tracing stops after hitting the first closest geometry, then surface attributes are evaluated.. If you need to know what is behind of your object ray-tracing must be continued using the same direction, but inside of object.. When ray-tracing does not hit any more geometry it returns color from backdrop image and/or environment mapping..

If you have backdrop that must be seen behind of your transparent object you can try rendering without backdrop without transparency, but render also special channel which will be used as alpha in post-processing software where you will do composition of LightWave and backdrop image/sequence..

Thomas M.
03-19-2007, 02:39 PM
Setting transparency to 100% is for sure a good start ...