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View Full Version : Help! targa alpha = reflection map?!

modeling-man
08-10-2003, 10:07 AM
Hey, this shouldn't be hard...but for some reason it is for me. In both Maya, and Max I cannot for the life of me get my targa alpha channel to act as a reflective map. My surface is just a simple plane, and my map is just a 128x128 image with RGB and an added alpha channel with painted in areas to show reflection. I have placed another object above, and to the side. Essentially the plane has enough objects around it to reflect SOMETHING...yet it just shows the diffuse everytime.

Here is what I tried in Max, and Maya, as well l tried a ton of other trial and error stuff. The stuff below is what I figured SHOULD work?!

Max:
placed the targe file in diffuse and reflective map sections. I read up in the help and it refers to "flat mirror map" I cannot seem to find this anywhere in the material library, yet when I even tried applying the map to a sphere it still refused to reflect anything.

Maya:
I setup a Blinn material, then as its material I used my targe file. Under reflective I placed my targe file, and played with the sliders and saw no change.

I've searched like a mad man through help docs and cgtalk forums but to no avail. I'm pretty tight on time to get this to work, and I'm pulling my hair out trying to figure it out. I'm not a super bad ass at Maya, but I figure with Max my setup should work?!

ANY help is much appreciated!
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ghilbli
08-10-2003, 10:16 AM
i'm kind of new to maya too. have you check that raytrace is on for rendering. in order to reflect , raytrace has to be on..
hope this helps
modeling-man
08-10-2003, 10:19 AM
well from what I read raytrace will reflect objects. However, a reflect map replaces what raytrace does so to speak. So when using a reflect map raytrace does not need to be used. Thus freeing up rendering time. Am I wrong?:shrug:

Thanks for the FAST response though.
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modeling-man
08-10-2003, 11:00 AM
Ok so I found and got "flat mirror" to work...problem is it doesn't use the targe file. It's like a preset of sorts. I also tried raytrace...I can load a targa file but it doesn't seem to find the targe alpha.
HELP!
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Peter Ryskin
08-10-2003, 02:27 PM
As for Max: The Flat mirror is excellent at making Mirrors, dirty or not.

If you read the section in the help about Reflection Mapping, you'd see that Max divides Reflection into three groups (as far as the reflection Map goes); Basic (IE, a picture), Automatic (Auto-Generated Cubic Reflection) and Flat-Mirror (Again, Auto-generated, but flat reflection).

If you look at the top picture (in the help), you see the essence of what Basic reflection is/does.

Anyhow, you're on the way wrong track, since the reflection map does not have any sort of opacity control.

So, either use Blend to create the two materials you want to play with, or use Masks on your Diffuse and reflection maps.
modeling-man
08-10-2003, 07:06 PM
Ok this is what I need to do. Flat mirror, raytrace none of those will work for what I need to do. I've tried applying a map into the reflection map section and then tried using the alpha channel to represent what should be reflected and what shouldn't. Currently my alpha channel is just a big ol' white block in the cent er of my map. I figure I should be able to see a difference when I render out...but all it does is make the entire map lighter.
This is from the art test.

2) Weathered industrial wall with alpha channel, for a vertical poly grid, able to tile & rotate left/right only. Alpha indicates reflectivity level, white (value 255) in map indicates full environment map reflection (not needed), black (value 0) in map indicates no environment map reflection.

Is this something that is only possible in Maya?
Still completely lost.
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mr3dguy
08-11-2003, 01:32 AM
I dont have max with me but check you have applied a uvw.
Try using a bitmap for the reflection map. use the rgb channels instead of the alpha channel.
squib
08-11-2003, 02:14 AM
I just tried a quick test. Created a sphere and put a Raytrace material in the reflection map. In the Raytrace material there's a rollout called Basic Material Extensions, and I put the targa in the first slot there. Set the targa to output alpha as the mono channel output, and there you go! :D

As far as I can tell, you can only do this with the Raytrace material. The flat mirror and Reflect/Refract materials don't seem to have options for this. It'd probably still be possible to use those if you're using a layered composite material, though.

Enjoy!
modeling-man
08-11-2003, 03:01 AM
AWESOME:thumbsup:

I got it to work:)
Thanks so much guys...now to get this to work in Maya!:)
Couldn't have done it without your help!:buttrock:
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EricChadwick
08-11-2003, 03:11 PM
The Mask map type allows bitmap alpha to mask an effect in any kind of material in 3ds max. I use it all the time.

After you load the bitmap in the Mask slot, set Mono Channel Output to Alpha.
Tahl'eN
08-12-2003, 08:44 AM
In Maya, are you linking the alpha chanel of the targa to the ref chanel of the mat? Or are you just clicking the "image in" button?
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