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MrChristopherSL
10-04-2005, 01:34 PM
I'm trying to figure something out and am not sure how to approach it in Lightwave.

I have an object and I have 2 surfaces for it. I have a surface that I want to go across the entire object, and then I have a surface is essentially a label that I want to sit over the other surface.

The label has rounded corners and some grunge which breaks up the edges. So I'm trying to make the rounded corners and grunge stenciled, like a layer mask in Photoshop.

So in Lightwave I have the object and it has 2 surfaces in the Surface Editor. But I can't figure out how to control the top (label) surface with an alpha so parts of the underlying base surface show through it.

How do you control a surface using an alpha channel? I know I can do this on a surface component basis (diffuse, color, etc) but I want to do it for the whole surface.

Thanks,

Chris

hrgiger
10-04-2005, 02:11 PM
The alpha layer goes above of the 'label' layer and where the alpha layer is white (or varying degrees of white), the layer that it rests above will show through. You have to copy and paste your settings into each different channel (there are copy and paste functions for layers). There is no apply to all channels fuction that I'm aware of. But, once you have it setup, you can create a preset from it and then apply it to other objects and all of the settings will be copied into each of the different channels of the surface you are applying it to.

MrChristopherSL
10-04-2005, 02:54 PM
Hmm. I'm finding LW's surving confusing.

Question. Is it possible to have one polygon share 2 different surfaces?

Chris

hrgiger
10-04-2005, 03:17 PM
If by that you mean, can a polygon in Lighwave be assigned more then one surface in the surface editor? Then no.

But you can blend textures in a multitude of ways over a single surface.

Lightwolf
10-04-2005, 03:22 PM
Question. Is it possible to have one polygon share 2 different surfaces?

Nope, they can only share the same surface. You can however copy single layers, or complete layers from the texture layers of one surface channel to another.
9.0 might be able to help there with the nodal system (if it allows for different surfaces to share a common nodal shading tree, which I hope it will do).
Cheers,
Mike

Lightwolf
10-04-2005, 03:24 PM
One more thing:
You can apply your label to both surfaces and use a common Null Object as a reference object for both instances of the image on each layer. This allows change the positioning, size and rotation on both surfaces at the same time by moving the reference object about.

Cheers,
Mike

MrChristopherSL
10-04-2005, 03:58 PM
Ok, thanks for clarifying that. It wasn't clear in the manuals. I'm a bit surprised of this limitation but at least it gives me an idea of how to proceed.

Thanks,

Chris

MonroePoteet
10-04-2005, 04:10 PM
I think what you're calling a "Surface" is what LW calls a "Layer". Any single polygon in an object has a single surface, but many "Layers" can be applied to that single surface.

Try experimenting with the "Add Layer" button in the upper left of the Texture Editor with an object that has a single surface. I think adding your Label is as simple as adding an Image layer to the Color Channel on top of your "Overall" texture and sizing/moving it to the position you want. The alpha channel in the image (i.e. the masked selection) should be respected in the color channel.

Then, if you wanted to grunge up your label some more, you can add a Procedural Fractal Noise on top of that. Or make it more luminescent toward the top, use a Gradient. LW's texture layers are very versatile.

mTp

MrChristopherSL
10-04-2005, 04:51 PM
Ok, I'm slowly figuring out how this works. I'm used to using another 3D app that easily allows you to throw many textures on the same piece of geometry.

I understand the difference between Layer and Surface. I just wasn't sure if LW could overlay multiple surfaces.

I've been trying to experiment with the reference object thing for texture placement and again am running into more frustration. I downloaded and watched the video demo from the video tutorials but for some reason it doesn't work quite so easily for me. I got it to work once, but the null object didn't correspond to the position on the object. The null was a ways away (not directly over it like in the video).

Now for some reason, when I try and select the null all I get is this little cross hair that move independently of it. When I try and select the Null object from the Object popup list, the list automatically pops me back to there sphere object.

I'm just confused what's going on.

Thanks,

Chris

MrChristopherSL
10-04-2005, 05:01 PM
Ok, so I opened a new file and am trying the reference object for texture placement thing. However, what I don't understand is why the texture is offset from the null object. The video shows it right above where the texture is. I have a sphere with a simple bitmap placed on top. When I hit the use reference object, the texture (set to Reset mode) disappears. If I move the reference object around I eventually see the bitmap appear but the null is no where near the object, much less right over where the texture is appearing.

Chris

gerry_g
10-04-2005, 06:38 PM
When I hit the use reference object, the texture (set to Reset mode) disappears. If I move the reference object around I eventually see the bitmap appear but the null is no where near the object, much less right over where the texture is appearing.

Chris


Positin the null over the object before you make it a reference object for the texture and give it a key or have autokey turned on

MrChristopherSL
10-04-2005, 08:08 PM
Ok, thanks. I'll try that.

Chris

Dodgy
10-05-2005, 05:22 AM
First of all, just using an image whicah already has an alpha channel will clip that image using the alpha, so you don't have to do any complex layering. Just add the 32 bit image above your base image, and it'll be composited on top (being transparent where the alpha channel is black).