Dirt: How?

[AJLynn]

I've seen a lot of talk about dirt mapping, and understand the concept, but I'm not really clear on exactly how to do it. Anybody got tutorials or pointers? For example, I want to do a wood drafting desk like you might see in an architecture school - 10-20 years old, been abused by undergrads with Olfa knives, all dirty and warped with metal ends plates that have peeled and scratched paint.

 

Say I'm using VRay, might move it to Maxwell later. Am I best off trying to do a procedural texture, or Photoshopping a wood map?

 

My textures are usually pretty boring, so I'd like to learn a lot more about this.

[DennisHolland]

You could use a specular map for scratches in the original map, in combination with an applied blendmap and set blending to 50%.

 

In a lot of situations you can brush a dirty texture in Photoshop by putting a new layer on top of the original and scratch it up, save. After that you can save a bump by deleting the original layer and set the left over scratchlayer to grayscale and invert to get the scratchy look. This way you have the same dimensions and locations bump/scratch. Try to put the same bumpmap in the specularmap slot for a finishing touch...

 

Quickdirt from Digimation is a very good option to dirt up things but the most relaxed way to have dirt all over is getting an aged texturepack from Totaltextures or Marlins'...

 

Good luck,

Dennis

[3dp]

just to add

yes quickdirt works but can be a little sketchy in the stability from my experience and would give you a result similar to the look of the ambient occulsions shaders in mental ray

if you have mr give that a try and reuse the maps as a good place to start

[STRAT]

does Vray have an AO shader?

[Chad Warner]

version 1.5 will have it.

[ShaunDon]

Chad, are you referring to that mythical winged beast that Chaos promised us for May of '04? I'm not bitter or anything, it's just a little fantastic that it's still in beta a year and a half later.

 

Oh wait, the DR controls are crappy. Maybe I am bitter. ;-)

 

Shaun

[Chad Warner]

I guess what I should have written was "eventually 1.5 will have it"

[AJLynn]

Thanks guys. I'm not looking to buy anything so I think I'll try Dennis's suggestion. But I looked at the 3dtotal aged textures and they look pretty sweet... maybe I'll have to copy their style

[vizwhiz]

AJ

 

some info

 

**

 

http://vray.info/features/vray1.5_preview/

 

V-Ray 1.5 Technology preview

 

Here are some of the recent developments for V-Ray 1.5 for 3ds Max, expected this fall. Some of these features were shown at SIGGRAPH. Thanks to Vlado for sending us this preview!

 

Motion blur for Particle Flow systems

Image-based lighting (IBL)

Improved rQMC sampling

Improved photon mapping

Sun and sky system

Dirt shader and ambient occlusion

Fast SSS approximation

Physically based camera

 

**

 

hope This helps

 

randy

[AJLynn]

Dirt shader and ambient occlusion with the same tech. Huh. Never would have thought of that. I hope that works out well.

[William Alexander]

www.dvgarage.com has some free dirt / grunge images and tutorials in those regards, last I knew.

 

Take pictures and through the channels extract what looks like dirt

 

A couple more thoughts

Cheers

WDA