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Giacomo99
01-19-2007, 01:14 PM
Hello-

It's easy to get a procedural node to act as a displacement map:

http://home.earthlink.net/~bucket/ProcNode.jpg

But when I try the same thing with an image node, nothing happens:

http://home.earthlink.net/~bucket/ImageNode.jpg

What am I doing wrong? Please advise.

KillMe
01-19-2007, 03:57 PM
you need to use the spot info thing to determine the normal direction then have the image displaced along the normal - image textures aren't 3d so it doesn't know which way to displace without the additional info - sorry but i cant tell you exactly how its done though - but seem to recall the answer is given in one of the lightwave 9 demo vids on displacement

LightFreeze
01-19-2007, 04:21 PM
Try doing it this way, replace the procedural with your image

Giacomo99
01-19-2007, 06:48 PM
I watched the video again--it's very helpful, but it raises a few more questions. Mainly:

1. Why is node-based displacement still stuck off in its own window? How is node-based displacement in the displacement window different from node-based displacement in the shader window? Wouldn't it be easier to just do it in the shader window--that way the information would be available to other shader nodes (e.g, color).

2. Why do procedural textures require additional math to displace properly in the displacement window, but require none for the shader window? Why (as far as I can tell) do image maps require additional math ALL the time--they're an array of greyscale info, just like procedurals, so what's the difference?

Please advise. I don't have a specific assignment I'm applying this to--I'm just trying to get a handle on the underlying principles here.

Giacomo99
01-19-2007, 09:19 PM
Hello-

I tried the thing you posted, Lightfreeze (it's the same as in the NewTek video tutorial) and it didn't work. Weirdly, Layout displacement recognizes the image node as a *constant* (i.e, flat color)--it scales the object up based on the opacity of the map.

Anyone else out there?

Dave Jerrard
01-20-2007, 03:25 PM
Did you take the alpha output from the image or the color or Luma output? If there's no alpha in the image, you'll just get a constant value, which would look similar to scaling the object.


He Who Hasn't Done A Lot In Displacements Using Nodes Lately.

Giacomo99
01-20-2007, 05:51 PM
Hi Dave-

The solution, as it turned out, is that image nodes can only be used for displacement if MipMapping is turned off for that particular image node. The issue was finally resolved in the thread below (from the "Node Developer" area)--

http://www.newtek.com/forums/showthread.php?t=62117

--and I'll just restate my general rage that this "interesting quirk," like so many others, isn't mentioned anywhere in the LW documentation.