How do you make decals?

[Dram]

Could someone help me out and explain what exactly decals are, and how you create them? Are decals just separate texture alphas, you place on top of your 3d models?

[Zanrok]

Decals are essentially "stickers" you place over an object to give it the effect of dirt, color, whatever.

You can do achieve this many different ways, depending on the game engine you are using of course.

Essentially, you need to create another texture with an alpha in it, to get the best effect you want to blend or gradient the alpha so that there are no hard cuts when placing your decal on your object.


1. So create a texture with an alpha blend on it.
2. Make a plane
3. Apply the texture to the plane
2. Place that plane over the object you want the decal on.

And your done, let me know if you still have any questions.

[Autocon]

When you say an alpha blend on it do you mean not full white? like some grey to make the whole decal kinda overlayish? If not then how exactly do you make and alpha blend?

Also if you are going to use a decal that you plan on using on multiple objects such as some graffiti would you have to include that that decal in your presentation sheet of the model? I see lots of people use decals in models but they always seem to be on the same texture sheet as there model.

Thanks for the info though

[Cryrid]

When you say an alpha blend on it do you mean not full white? like some grey to make the whole decal kinda overlayish? If not then how exactly do you make and alpha blend?

I believe that is what he meant, though there are some times when you may wish to have a hard edge. Power outlets in Half Life 2 for example.

[Tiros]

Hmm, I think he might actually have ment adding a small gradient to the edges so it fades out a little, and not giving a very hard pixelated look

Cheers