Unreal Development Kit - UDK - World Position Offset

This is an example of how to use the `world space offset`in the unreal (UDK) shader. This will consist of a mixture between the `Mesh Painting`function and the shader set up a certain way to give you the desired result.

You can use this for fog or mist as shown in this video, but also to offset certain aspects of different materials as they move around the level.

If you want to see more of my tutorials, please visit my web page at:
http://www.chrisalbeluhn.com/3D_Tutorials.html

Hope you enjoy.

Category:

Education

Tags:

• UDK
• Unreal Development Kit
• World Space Offset
• UDK Materials
• Vertex painting
• Mesh painting

[AngelThearZ]

So it seems like I can but blend to translucent and add the time move thingy in so the fog will move but when i start using my Mesh editor and use my eraser wich is 0 then it won't stop the fog from moving.. it will slow it down but not stop it, can you help me with this too? Hope you respond soon and thank you very much man!

[seescruffyrun]

@AngelThearZ The shader doesn't have a rhythm to it.. With the way i have the shader set up, each vert loops, but it is on a different time length. This causes some irregularity in the animation. If you would like a different feel to the shader, adding 0 won't change anything, but multiplying by 0 will. You can set up your shader so painting the verts with red will add to the time (offsetting the time of the wave) and painting with blue will multiply ( which will stop the animation if set to 0.)

[AngelThearZ]

Hey man I followed you UDK Mist guide on your page and I just copy pasted your picture wich you made in photoshop and I reduced it's size to 128x128. My result was kind of blocky-ish fog. Now can you help me with that? And the fog material I've made has it's blend set to additive but now you're telling me I should put it to translucent, wich one should I do? Please respond and thanx for your help so far:)!

[seescruffyrun]

@AngelThearZ Additive will give a different feel to your fog than translucent. It doesn't really matter which you use since it's entirely up to you to make it how you want it to look. The guide i have is simply that, a guide. Never hesitate to experiment to see what works and what doesn't, and why. As for the blocky texture, that could be anything form the pixel density of your shader, or a bad texture compression. E-mail me with a pic if it continues and I'll take a look at it.

[seescruffyrun]

yes, There is no limit to how big the geometry can be, and if you want to make the edges soft, well, it depends on what you mean by that.

If it's through the material, just alpha it out. If you mean 'soft' as in slower, just make the vertex colour value less and it will wave slower. If you mean the edges where it connects with geometry, there's a tutorial for that on my site. look for the 'UDK Mist/Fog' tutorial.

fog/mist, flags, clouds. this method can be used for a LOT of things in game.

[AshleyLesnie]

It can be used for fluid surface with any method? I tried it, but I can't paint fluid surfaces with the Mesh Paint Tool... There are any other method that I can use for simulate long waves? Thanks for your help.

[nathanb117]

Thanks dude, awesome tutorial, helped a lot

[PuLsE0o0]

@ncshuriken It isn't necessarily the "Best" engine though it is widely used for it simplicity of use. And it has moderate graphics and sometimes if the artist is good enough quite nice graphics still with some very good performance.

[videoGunZ]

cool, thanks :) its like a fluid surface info in ut 2004! ... just better :D

[wyldhunt]

Perfect. I was about halfway finished re-inventing this very thing for clouds. You just saved me a weeks worth of re-inventing your wheel.

Thanks.