UV wrapping

[cs00bren]

I've created a charator and i want to texture him. i haven't really played around with UV texturing that much. what i want to do is unwrap my charator import that in to photoshop, then paint an amazing skin and cloth texture then reimport that in to houdini.

i've haven't reallydone anything like this before so has anyone got any pointers. can Houdini export a uv texture imgae, I've tryed save texture map option but it doesn't unwarp ot very well i have attached the image it produces. and then how do i re-import it. do i just use a standard VEX super material.

I've also found so good little apps that unwrap .Obj wound it be better to use one of these programs rather then Houdini. if so can anyone suggest any.

Sorry for the long post bren.

[Mcronin]

I'd just use Houdini. If you head over to the Vislab site there's a couple texturing videos that will help you. The Watermelon tutorials mainly.

Basicly, the process you want to use is:

1. Use multiple group SOPs, group faces of your model so it'll be easier to work with. How you group the faces is going to be determined by how you intend to apply your UVs so you'll have to put some thought into it. For example: The leg from the groin to the ankle is one group because you want to use cylindrical UVs. Same with the arm from the shoulder to the wrist. You want to use planar for the torso from the shoulders to the waist maybe, so that's another group. You just continue until all the faces of your model are in one group or another. Make sure to give each group a unique name that makes sense to you.

2. Start applying UV Texture or UV Project operations to the groups. cntrl-rmb in a viewport and change a UV Viewport to lay out your UVs. You'll need to use some of the other UV Ops, like UV Edit and UV Fuse, etc. to get it all laid out.

3. Once you have the UVs laid out, you could just right click a SOP and select "Save Texture UV to Image", but this option is almost completely useless in Apprentice. You are limited to 640x480 and there will be a water mark. Instead, maximize your UV Viewport, and take a screen grab of it, and use that. Use the screengrab as your template in PS or Gimp or whatever to paint your maps.

4. Once you have the map painted, apply it to your model in Houdini and you are done. You can use a single shader and map if you want, or multiple if you need. I think the watermelon videos actually use two maps and two shaders. You can use Supermaterial if you want, but it's a very simple process to create a Shader in VEX Builder with the exact lighting model and options you want if all you need to do is apply a texture map to the model. When you get your model's UVs and textures all laid out, and the maps painted, post again and I or someone else here can help you build the shaders if you like.

[cs00bren]

Cheers for that reply i thought it was how you did it. thanks for the advice about the UV view port it makes the whole thing a bit easier i will have to spend a couple of nights trying to texture the man.

hopefully by the end of the week i can have the finished model done.

cheers bren.

[TheUsualAlex]

Ouch... Your sshot looks pretty painful...

Couldn't you just break them into separate parts to do UV editing and merge them afterward? It's been a long while since I"ve done any UV editing now... But of course, there's always that seam which I don't like to deal with. A friend of mine simply use the DeepPaint's 3D painting abilities to fix the seam...

[cs00bren]

Cheers for that

Two questions

One: in the watermelon tutorial in his view port he can see the textures on the object. i've tryed suing VEX view but all i get is a grey. any ideas.

second i can work out if he puts the UV texture before or after the shader. so does it maker of any of the UV's if it goes before or after.

cheers bren.

[Mcronin]

If you are using Supermaterial, just go to the shader's OpenGL tab and put the texture in the Texture map slot to see it real time in a viewport.

I'm pretty sure in most circumstances it doesn't matter if you apply the UVs or the shader first, however, it just makes more sense to apply the UVs first in most cases, especially when using 2D images for textures. Mostly because you'll probably be painting an image based on the UVs. Secondly, you may put together a VEX shader of your own that requires UVs, and I'm not sure how Houdini would handle it if you modified or added UVs after such a shader was applied.

[cs00bren]

Cheers it was in the Open GL bit

a question about VEX displacement maps. for some reson i get funny scan lines in the render an ideas.

cheers bren

[edward]

In the object you're rendering with displacement shaders, go to the Render tab of the parameters. Turn on Displace Bounds and set the number to the maximum amount of units that your geometry will be displaced by.

[Jason]

The SuperMaterial is a little cryptic - it's parameter names and the way it doesnt have a parameter name for the texture map file that automatically gets picked up by the OpenGL tab.

As for the displacement bounds, I once spoke to Mark Elendt about mantra being able to spit out a hint about the maximum displacement it encountered during a render. This would be so handy for achieving tightly fit displacement bounds. Let's hope he does this sometime!

[cs00bren]

i've been busy doing stuff so i've only got back to the uv stuff. what i still can't understand is why you can't uv wrap. i can UV unwrap so in theory it should be easy to do the opersite and wrap it up again.

maybe i could write it my self i need to know how to script.

bren

[edward]

What is uv wrap supposed to do?