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Kvaalen
12-24-2003, 03:01 PM
I'm trying to make the Z depth of an image the RBG value of the image. I thought the best way would be using a Channel Boolean tool, but when I apply the Z buffer to any of the channels it applies a black and white image that is the same as the Alpha channel. Am I doing something wrong? Is there another way to do it?

Thanks for any help. :)

Robert Zeltsch
12-27-2003, 05:14 PM
Hm... I`m not sure if I understand you. Do you want to create a Z-Buffer from the RGB values?
If yes, then it is easy with the Channel Boolean Tool (Bol).
Simply enable the Auxilary Channels and apply the desired channel to the Z-Buffer.
If you want to create RGB-Values from the Z-Buffer (the result should be a greyscale image) then the Channel Boolean Tool should also works. (Apply the Z-Buffer to the RGB Channels)
But your problem sounds strange, so try the following "workarounds":

1. Use a AutoGain Tool (AG) to "expand" the Z-Buffer. It is included in module 2 of DFX+
Since you are a LightWave user, I assume that you are using DFX+. (I have seen your avatar in the newtek forum... ;) )

2. Use the Depth Fog Tool with a Black Color on a white BG-Tool
by applying your Z-Buffer on the green input node. The Background tool goes into the brown node.

Good luck!!
:)

Kvaalen
12-27-2003, 05:58 PM
Thanks for the help.

Yes I do have the LightWave + DFX+ deal. :)

My problem is the later: "If you want to create RGB-Values from the Z-Buffer (the result should be a greyscale image)".

But as I said and you mentioned, it gives me a black and white image the resembles the alpha channel instead of the greyscale image I see when I look at the Z Depth in the viewport.

For the time being I've been doing the second seggestion. Using black fog on the black and white image the Channel Boolean tool gives. It works fine and suites my needs, but I suppose it probably takes a little longer to render per frame.

Has anyone else tried this and had the same problem?

m.d.
12-31-2003, 06:23 AM
hey Kvaalen,
ya I have the same problem Zbuffer is just black and white not greyscale...I thought i was doing something wrong?

PolyMangler
08-27-2004, 02:55 PM
I thought the best way would be using a Channel Boolean tool, but when I apply the Z buffer to any of the channels it applies a black and white image that is the same as the Alpha channel.

could this be because the z-buffer isn't scaled in the same 255 range as normal rgb? If so you'd have to find a way to normalize the z-buffer. I think a dfx tool has that exact option in the color modual

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