Best approach for midpoly road & terrain?

Mr_Drayton

Hi Polycounters, I need your help today.

I'm not very sure about finding the best solution to model a simple terrain with some integrated roads in Cinema4D.
In particular, roads must not be polygon strip overlays, but part of the terrain geometry itself. Target device is iPhone3GS/4, so I can't put too much detail in the terrain, but at least I want something not too spiky.

This is my actual road layout:

Probably a bit too much polygons, but that's fine for now (I will reduce them a bit, they're Sweep objects).
So, I need to fill the 4 empty areas with something like a polygon grid, wich must also be welded to the road edges, in order to have a coninuous mesh.

At the beginning I tried to make the terrain polygon by polygon, extruding road edges repeatedly until everything was filled up, but the result were not so good. Probably I must do things with just more precision.
I also tried to create a Landscape mesh and then projecting the road splines above it, but road overlays are not what I'm looking for.
What would you suggest at this point? Thanks for your help.

Mr_Drayton

Yes, I already did a search here, but as far as I read, solutions were different from my needs (there was something related to projectors and special shaders, that I don't mind to use on iPhone).

By the way, probably the manual method is the better trade-off for this task...

leechdemon

I just got done working on a scene that had a ton of dirt roads going through some hills. Basically, I modeled the hills and the roads separately, rendered an overhead projection, then applied the result to the hills. The result was that the hills had roads going over top of them, and there wasn't any wasted geometry. For an extra effect, I went through and used the roads to deform the hills, creating a subtle groove that the road texture sat on in the hills. Was a much easier process than anything spline-based or otherwise that I'd seen.

Joshua Stubbles

You can just build a really rough mesh in your app, then (if you have it) import that into Zbrush and do a simple sculpt on the mesh. Run decimation master to get the vert range in check, then run UV master and export the mesh. You'll have to stitch the terrain to the road, but there's a script for quickly doing that, with Matt Lichy's Turbotools "stitch" function:

Mr_Drayton

leechdemon wrote: »

I just got done working on a scene that had a ton of dirt roads going through some hills. Basically, I modeled the hills and the roads separately, rendered an overhead projection, then applied the result to the hills. The result was that the hills had roads going over top of them, and there wasn't any wasted geometry. For an extra effect, I went through and used the roads to deform the hills, creating a subtle groove that the road texture sat on in the hills. Was a much easier process than anything spline-based or otherwise that I'd seen.

So, something like in Reckless Racing, wich was using a big texture for all the racetrack... Good idea.
What resolution was the final texture you got?
iPhone supports up to 1024*1024, but I guess using more than one for the terrain could be a good choice.

@Joshua: looks a bit more tedious, considering I don't have/use Zbrush now...