View Full Version : Roads over terrain - BG conform

11-15-2008, 04:59 AM
I see by past posts that this is a recurring topic. However, I've found no workable solution. I have a mesh representing a rather hilly terrain. The road path and such have already been worked out in AutoCad and exported as this mesh which I brought into LW 9.5. I have roads and paths (at Y=0) in another layer. How can I "drape," wrap, however you want to characterize it, the roads and paths onto/over the topo? This seems to be a major problem in doing this type of visualization in LW -- I've run into this issue many times before. I understand that SU has a function what will do this, however I don't want to use SU.

I tried the old plugin POINTFIT, which, by its description, would have work perfectly. However it's no longer supported and simply crashes my modeler.

Any suggestions?



11-15-2008, 06:20 PM
There are modern versions of background snapping tools, that work with LW v9.5 perfectly:
Look at videos..

11-15-2008, 06:23 PM
Maybe cloth effects? Make the roads a cloth object and the landscape the collision object, add gravity and let the roads drop onto the landscape.

Another solution might be rendering a hightmap from the terain (give it a gradient material with the gradient working on the y-axis, white is top, black is bottom). Render also a map from your roads. Then bring those into Photoshop and add, subtrackt or multiply your roads onto the hightmap. Export the new height map and use it as a displacement map on a new plane (which gives a mesh which includes the roads).
Otherwise you coud mask the heightmap with the roads so that the new heightmap only displaces on the roads and use that map to displace the roads.

Stunt Pixels
11-15-2008, 06:31 PM
Stencil it on?

11-15-2008, 07:38 PM
I agree with stenciling.
You can also copy the landcape, stencil, cut out the stencil, extrude it a very tiny amount up and paste back on the original landcap.
Another point conform tool that works well is this one:

11-15-2008, 08:22 PM
Problem with just stencil though is that the road will conform to the landscape contour rather than being horizontal at every point along. Here's what I'd suggest:

Copy the stenciled road, undo stencil, and paste the road to another layer
Isolate outer points of the road, create a poly, and bevel it inside so you get a road that's flat at each point
Extrude it upwards
Boolean subtract the extruded road from the orginal terrain

Voila. A road that winds up/down, but one that's ready to ride. If you're going to animate a vehicle, this should work OK with sticky surface in Layout.