Some questions on the benefits of the Mesh Paint tool

[seenooh]

Hi,

I just want to know what's the difference, in terms of performance, when I create a material that blends between say two diffuse textures using a mask (traditional way) and when I use the Mesh Paint tool to do that? I want to also understand when do I use the traditional way and when do I use that tool?

Thanks.

[ambershee]

Mesh painting uses the "colour" of the vertices of the mesh, whereas doing it in the material shader uses the pixels in the textures.

I'd assume that mesh painting is more efficient, as you will be processing considerably less data (unless your have fewer pixels in your mask than verts in your mesh - which is possible of course).

Doing it in the material however will give you per-pixel control, instead of per-vertex, so it will be more accurate.

[seenooh]

Where does the colors get stored? I thought it paints over the UV map....

[ambershee]

It will effectively (or literally) be in the actual vertices of the mesh.

[seenooh]

I see, thanks alot ambershee.

What about the overhead it creates when you have color information stored in the vertices? Or there is none because perhaps every vertex already has color information but set to black/white/null?

[ambershee]

I believe colour information is stored in leftover bytes in each vertex, so as a result there is no real cost in meshes having it.

[Solid Snake]

It's also cheaper than using textures in the majority of cases. However, it's accuracy is dependent on the vertex density. Much like vertex lighting back in the old days. If you wanted better lighting and shadowing then, you just had to increase the polygon counts.

Now a days, we can reduce the polygon count since we use per pixel lighting.

[seenooh]

Alright, thanks alot guys. I understand much better now.

[EFF]

General tendency is to keep as small number of texture samplers in shader as possible(switching textures is relatively expensive). So if I can achieve same result, I'd choose mesh painting.

Besides texture masks are practically useless if you want to have huge variety inside your level.