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A.Russell
05-01-2006, 05:56 AM
I've had trouble with this before, though I can't find threads any more.

Basically, Lightwave will not allow simply adding an alpha map for transparency, you must give it an alpha image in the transparency channel.

Unfortunatley this is not working for me. In the surface editor I click on the "T" next to Transparency and select the appropriete UV map and black and white alpha image. However, it doesn't work.

This is very frustrating. How do you get transparency based on a B&W image?

Fozz
05-01-2006, 06:10 AM
Well, looks like you are doing it right. Using a simple black and white image in the transparancy channel should adjust the surface transparancy based on the image. Note that the image layer should NOT be set to Alpha though, that only makes it an alpha layer for the other texture layers in that channel. Also, might wanna make sure you dont have an alpha channel in the image you're using as an alpha :) Many alphas.

A.Russell
05-01-2006, 06:33 AM
Thanks Fozz. For good measure I saved both the rgb image and the B&W alpha image as 24 bit bitmaps.

Still no transparency! I'm using Lightwave 8.5

Fozz
05-01-2006, 06:42 AM
Ok then...uhm. Perhaps the Ray Recursion setting in Render options are too low? That can mess up the transparency rendering. You could also try using the image as a clipmap instead, see if that works. Or invert the image, since LW's transparancy works inverted compared to alpha, ie white will render transparent.

A.Russell
05-01-2006, 07:49 AM
In the Colour chanel I have a 24 bit bitmap of the colour image. In the Transparency chanel I have a 24 bit b&w image for the transparency with the white areas for where I want to mask.

Nothing has happened. The transparency image does nothing whatsoever. Even without rendering, I can see in Modeler that nothing has cvhanged.

This is with LIghtwave 8.5

toby
05-01-2006, 02:53 PM
See if it works as a cubic map instead of the uv. You need to judge it by the render and not how it displays, they can be very different. If it works with cubic projection, there's something wrong with the uv map.

If that doesn't do it, can you post an object and image map so we can check it out?

Dodgy
05-01-2006, 03:07 PM
You won't see any difference in modeler, you'll only see a difference in layout, either in opengl if transparency is switched on, or in the render.

A.Russell
05-02-2006, 01:30 AM
It seems Modeler and Layout weren't connected at the time, and that was why all the changes I was making in Modeler weren't having any effect. There should be something to indidctate a conncetion, I think.

Are there any settings I can apply so that transparency is rendered in Modeler's 3d view? That would be very helpful. I went through the options menus, but couldn't find anything.

Dodgy
05-02-2006, 03:21 AM
Nope, hopefully that'll come when modeler gets layout's opengl, as layout's ogl is so much faster.

lion111
05-05-2006, 10:59 AM
hi
i think you should turn transparency to 100 % and with alphamap in "T" you should see a difference also play with the settings (muli,diff.substr. etc)

it works for me
may be it helps
good luck