custom bump maps

[TwizardT]

i made some custom textures for my track and i want to make a bump map for them but i dont know how.
could someone tell me or maybe even make a tutorial for it? that would be awesome.

thanks,

TwizardT

[al167]

look at the stock sample files in the wiki and look at each channel of the image. try your best to copy these for your texture. in photoshop just use levels, brightness, and blur so you get each channel of your image to like the stock track bump maps. Also black alpha makes the wheel sit below surface, white alpha sits on top.(or was it the other way around, it been a while).

good luck

[al167]

also don't forget to make your textures seamless first. search seamless texture tutorial on youtube!

[JamieT]

Also black alpha makes the wheel sit below surface, white alpha sits on top.(or was it the other way around, it been a while).

Actually it's the blue channel that adjusts how deep the dirt is, and how far your wheel sinks into it.  If you make the alpha channel black, it will essentially turn off the depth in the blue channel.  Anything other than black makes no difference, therefore the alpha channel should be ignored on bump maps.

So a quick run down of each of the 3 channels...

Red - This is what a tradional bump map is used for, which is the lighting.

Green - This changes the colour of your dirt.  It allows you to blend the diffuse texture of the dirt with "Dirt Color" which is specified in the "Scene" tab of DE.

Blue - As described above, it adjusts the height of the dirt, and how much your wheel sinks in.  White would be like sand, black would be like tarmac.

Alpha - nothing.

[TwizardT]

thanks to both of you i think i figured it out now