UDK Tessellated Roof Troubles

Daedalus51

Hey Guys

Iam working on a japanese inspired environment in udk and want to add some nice dx11 features to some assets. Iam currently building a shrine gate and the goal is to have nice tessellated roof tilings. Everything worked fine with some testmaterials, testmeshes and tiling textures. So now, I unwrapped the roof of the shrinegate, put everything into udk, but I get some really strange results.

Problem is...the roof on one site tessellates fine, but the roof on the other site stays nearly flat. So it looks like Tessellation is applied from a specific angle, but I think that shouldnt be the case. Ive tried finding some tips here in the forum, but wasnt able to find something related to this problem.

This is the Shrinegate:


First, the uvs were overlapping, but I thought that could maybe the problem, so my new uv looks like this:


This is my shader network:


And this is what the tessellation looks like on the mesh (its just the roof for testing):


As you can see, the right side of the roof looks finne, while the left side stays nearly flat. I really dont know whats the issue here, so maybe one of you guys might have an idea what could be the problem. It would be very great to find out whats going on

THX

-Daedalus-

Angry Beaver

it almost looks to me like they're both being tessellated but that their "up" is at an angle that produces a good result on one face but not the other. have you tried this shader on other geometry to test it yet?

VelvetElvis

Did you mirror that roof plane? If so, that may be flipping the UV coordinates and causing your directions to be all wrong. If you are in Max, a simple Reset Xform after you get your UV's set usually does the trick as well as flipping your UV shell in the editor.

You shouldn't see any backwards text on your roof place, which a numbered checker texture comes in handy.

Daedalus51

@AngryBeaver: Yeah....it looks the same to me I tried the shader on the roof testmeshes you can see crawling in the back of my screens^^ it worked well with these exept one problem: the tessellateion gets flatter the higher you go on the mesh...or....should i say the steeper the angle, the flatter the tessellation gets on those meshes.

@VelvetElvis: Argh...thx man, totally forgot that.^^ Yeah I will try it later and post some results if iam able to fix this problem And yes....the roof was mirrored, but collapsed before doing the uv...so i think everything should be fine with the uv.

Thx for your help so far!

-Daedalus-

righteousouka

Try multiplying you height map against the world normals.



The image is from a tessellation and displacement Tutorial I wrote a while back.
Tessellation Tutorial

I find that using world normals gives a more consistent result than vector transform.

Daedalus51

righteousouka wrote: »

Try multiplying you height map against the world normals.



The image is from a tessellation and displacement Tutorial I wrote a while back.
Tessellation Tutorial

I find that using world normals gives a more consistent result than vector transform.

Aw Man! That totally did it! Thank you very much for the hint with the world normals Now everything works fine and it looks really nice. Once Iam done with some more assets Iam going to start a thread about my environment so you guys can check out there what this stuff looks like

Thank you again for your help! (I will also try the stuff you mentioned about baking the heightmap in 16 bit an doing some photoshop magic to get cleaner results^^)

-Daedalus-

darthwilson

@righteousouka Nice fix!

@Daedalus The tessellation looks great!! Really nice example you made! Keep it up!