my alpha channel doesnt work

hi there… got some problems with uv map.
i have already unwraped my model, and painted the texture. but they are like car stickers. i need to make some parts of my map transparent. i make a targa with alpha channel, load the image as texture (not directly in uv map with texface and stuff), and choose USE ALPHA from the texture options. then at the material settings i map with to UV. it renders with the map, but not with the transparent areas…

i cant just use the alpha options in the map_to menu (materials tab), cos i have black and white in my “stickers”, and AFAIK that option uses full black or full white for the alpha (or i am wrong ??)

maybe i can use some stencil stuff (read about this at elysiun) if its possible anyone can link to a tut about this or just explain how it works??

thanks in advance. (and sorry if you cant undestand some parts :expressionless: english is not my native language)

i suppose you mean a normal render, not game engine?

i think you can use “Alpha” mapping, it should use the textures alpha channel it there is one instead of black/white
also try setting the materials alpha channel to 0 and turn on ZTransp or Ray Transp
i can’t try it now so i hope this is not wrong, maybe you have to try on your own a bit :expressionless:


I’m confused

well anyway, I bet you frogot to press the ztransp button [and I guess set the alpha value of the rest of the material to 0]

you would probably be able to tell the alpha of the texture was working if it properly covered up thing below it, then you’d press the alpha button in the “map to” buttons, and also make sure you have ztransp pressed if you want your material to be transparent. Also, the reason you’d set the alpha value to 0 for the material, is because the default mixing mode [“mix”] would combine the color of the texure with the textures below it by mixing using the alpha value

haha, first

soryy dudes… but i cant understand the way you talked. i will post a picture, so you can understand better.
this is how its suposed to look (with just the color map). i painted the map yellow to give the car color. this is the result i want, but what i was asking was: can i remove the yellow part of the map in the render, so it shows just the white and the drawings??

thanks for taking the time to help a noob blender user %|

sorry, don’t understand :expressionless:

z3r0 d ??? do you ?

try this to see if wath im talking is possible:
make a uber pretty cube. then unwrap it, and apply to it a texture (think about some dice) but instead of painting the color for your dice in the map, you use some crazy alpha settings, so you can leave the dots of the dice at render time, but you can change the color of the dice with blender internal material editor… does it makes sense?? if so, its possilble?

Yes it is possible. Just create your original texture with an alpha background (use a tga or png image). Then where you load your texture image (F6) depress the “use alpha” button. “Map input” set to UV and “Map to” set to color.

Note that there are other methods as well – using a black and white image as a stencil, or usung a decal so you don’t have to UV map.


and press ‘ztransp’.