PDA

View Full Version : Masking a tiled texture


boxy
09-11-2007, 01:01 PM
Hello
I have a feeling this comes under 'basics I never learned!' But I'm having trouble figuring out how to make a transition from the snow texture on the left to grass on the right using the black and white alpha map shown below. The complication is that the grass needs to be a flat projection so I can tile it, otherwise I wouldn't get enough detail on a single large map.
Any solutions would be much appreciated
Thanks
Boxy

http://www.savbox.pwp.blueyonder.co.uk/posts/1a.jpg

http://www.savbox.pwp.blueyonder.co.uk/posts/2a.jpg

davesink
09-11-2007, 02:05 PM
Load your alpha map into the grass textures Alpha channel and set it to "projector" using the dropdown menu. Set it to UV and that should do it. Here's an example using procedural shaders, but it should work the same with bitmaps.

slouchcorp
09-11-2007, 02:29 PM
or paint the area for snow or grass with a vector map on the polys, then use the vector map option in the alpha of what ever shader, drop the vector map in the link and itll be constrained to that.
its in shaders, texture. effects menue.

Mike

boxy
09-11-2007, 03:16 PM
Thanks both
Dave that has worked for now but I would like to try Mikes' way too. Now that I have discovered how to do this I can think of a number of uses :)
Cheers
Boxy

govinda
09-11-2007, 06:36 PM
If you can tile it, great, but most of the time this is one biiiig texture so as not to have it fall apart. I just take a shot of my plane from the top down, go into photoshop and paint the path, and then remap it back on as 'flat' with a -90 degree rotation on the P axis in the texture tag coordinates. It'll be pretty big, like 4k and maybe 16 bit if there's displacement, and use the mograph displace deformer so that the displacement is flexible. After a few iterations of changes, if the path isn't changed, I might bake it (thus the mograph displace deformer, and by 'bake' I just mean 'current state to object,' though you can do a real baking also). So that's the alpha channel. In other channels, using 'Projector' is a real help as you can have those channels (color, diffusion, bump, etc) tile while your alpha stays as one block.

boxy
09-11-2007, 07:03 PM
Ah right, sort of the other way round to Dave's suggestion. I'll play with that one too, thanks Govinda :)
Boxy

georgedrakakis
09-12-2007, 06:59 AM
hi boxy,
you could also use c4d's powerfull fusion.
set blend channell to ice mat,
set base channel to grass mat,
enable mask, and set mask channel using you alpha map, or a gradient with a bit turbulence
http://i122.photobucket.com/albums/o271/studiomoccoro/111.png

http://i122.photobucket.com/albums/o271/studiomoccoro/222.png

CGTalk Moderation
09-12-2007, 06:59 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.