Rock Face / Cliff modeling

[meshfx]

Hey all,

I am just looking for modeling tips for rock face and cliff etc. In Max I have tried making a plane and dragging the verts around, and then a box and doing the same. I always end up with sharpish looking edges and well items that do not look like a convincing cliff.
Is there a standard that people adhere to where making cliffs, should I stick to a certain number of faces, how much is too much and can be hidden with a decent texture etc.

Like I said, just looking for tips / techniques.

Here is the sort of thing I am knocking out.



Thanks

S.

[MadV]

I'd go for Zbrush or Mudbox, get the basic scale and form down first in Max, and export to Zbrush, do the rest of the work there, make a normal map out of it. Maybe I'd have to make a new low poly, but the end result should turn out pretty nice.

But, if you're only option is Max, which isn't a bad one of course, check out these two posts:

http://boards.polycount.net/showpost...5&postcount=73
http://boards.polycount.net/showpost...2&postcount=74

In fact, check out that whole thread, should be something to learn there for most.

I don't think you should worry too much about hard edges either, unless they're really ugly. After all, it's not unheard of for rocks to have hard egdes There's a lot more rock faces (in games) that look dull because they're too smooth looking.

[robin1232]

another reason why it doesn't look realistic is because you won't build a dock pointing to a cliff

[Xendance]

another reason why it doesn't look realistic is because you won't build a dock pointing to a cliff

River in a canyon?

[meshfx]

yeh it is just placement and testing of imports and the like. In that scene now I have a road segment a couple of columns and a big steel door.. none of which are final placement.

[Nawrot]

Do you have ZBrush or something similar? Well this method can be also done in max with use of soft selection, but its more work. I think i make some picture howto soon, this question pops every month or so.

Here is my workflow (i use max and zbrush)

1 - make CSG model of your cliff, then export as t3d and get it into max. Recreate in max. This step is only if you want to make mesh that fits exactly your level. If it is not needed then just make boxy mesh in max.

2 - to start with max you need very boxy mesh, but keep in mind that you need to split its surface into squares, density of vertextes when splitting is crucial to good effect. Keep it evenly split. When you have that boxy mesh, convert it into poly. Then use Ring, loop and connect to split all surfaces into nice boxes. Keep checking for open edges and loose vertexes inside, ZBrush dislikes them. When you have your whole mesh split evenly, its time to export it into zbrush,

3 - get it to zbrush then subdivide (up to 100-200k), smooth and make more randomly looking. I usually work on higher resolution meshes, then export one above very low poly orginal. I repeat this step after tormenting my mesh a bit in zbrush i get it back to max, add geometry holes etc. I do it in zbrush and max until i am happy with all. You can do it all in max with softselection, but it takes much longer tilme.

4 - time to uv unwarp in max. I uv unwaarp whole mesh so it has seamless texture (this is important for rocks, because seams on rock look ugly). When i have whole surface nicely unwarped, I split that mesh into sections. I do not modify UV mapping (1st chanel) from previous step. This is diffuse mapping and it is final for textures, i resize textures in udk material later.

5 - for each mesh after split i make second UV and copy/stretch 1st uv to fill whole space for lightmapping in second uv chanell.

Few tips about material:
-split all meshes along floor horizontal surfaces, then use world position node to mask those seams with worldmapped ground texture (that does not use uv mapping from meshes)
-use linearinterpolation with vertex color or RGB texture mask to blend different textures and paint meshes.
- when uv mapping diffuse chanel think about how you cut your mesh later, make it so cuts on mesh are same as those on uvs.
- if you use vertex color then optimizing mesh will make it harder to paint, so leave that square structure, becausee it begs for vertex colors. But if you want to save polycount you can add colored RGB mask instead of vertex color. And use DECIMATOR plugin from zbrush to lower polycount.


Ps. i really need to make some picture howto for all this.

[meshfx]

Thanks for the breakdown. I can try and use Mudbox 2010 or 2011 as one of the artists where I work is going to let me install the beta on my work machine.

I used ZBrush previously but just for adding some details to some meshes but never working a flow between max and ZB. I am hoping to be able to create the blocked out version in Max and throw that to MB for some detailing and knock out a Normal map from there (fingers crossed) or bring back the detailed version into max and bake on the textures from the high to the low (this is all in theory so far!!).

Thanks for the info, I will post an update soonish.

[Nawrot]

I made it with pictures: How to make rocks
When i get some time i write second part about vertex color and material for this kind of meshes. But that info is already available in various tutorials.

[danimal']

Off the top of my links list, here's two tuts describing rock workflow:
http://stephenjameson.com/tutorials/...rock-tutorial/
http://picasaweb.google.com/TheEnola...25054373907330

Ultimately, the work flow for anything 3d is pretty much the same. You either start low poly, likely UV it at that point, go high poly and sculpt then either polypaint or UV paint. Or, you start high (or with a super simple low then immediately to high), sculpt away, retopology, and UV the low (same options for texturing as other work flow).

[zoltanjr]

If you have vue can do some pretty good erosion etc in there

[Orindoomhammer]

what i like to do is use a plane with 12 x 12 and start there. i add more as needed. if your looking for textures then i cant really help with that as i use a combonation of photo shop and mapzone2 as well as genetica viewer for textures. but the models are quite easy when you get the hang of it. as far as rocks go i just make a box tessalate it and then applay a noise modifer and then tessalate it again. use small values or it gets really distorted. its abit more complex and involved then that but its the basic workflow i go threw.