How can I select multiple Plane edge vertex that overlap and average their possitions


To explain this a little better. I have 6 separate plane surfaces each with it’s own UV, Displacement, The 6 plane are set up in a grid so the edge vertex of each plane that have another plane next to it overlap.

Basicly i have 6 terrain sections, but the height map for each of the 6 are different. So of course none of the edges between the terrain section match. How can I select the edge vertex of the terrain sections that overlap each other and merge the vertex positions on the Z axis to an average position between those vertex that overlap on the Z axis (edge verts of separate terrain sections).

Also is there a way to do this without having to apply the subdiv and displace to each section and join into one mesh, id like each of the section to remain separate objects with their own UV and materials maps etc.

Urgent help needed PLEASE. Cheers J

If I’m understanding you correctly, you should try the Shrinkwrap modifier, using the “Project” Mode, both Negative and Positive directions. Set up your targets right, and you can get one mesh to basically match up with the geometry of the other where the overlap happens.

Better yet, build a small bit of terrain that runs along the seams, then use a Shrinkwrap modifier with some Vertex Groups to gradually merge each edge with the seam terrains. In the end, you won’t render the seam terrains, rather they guide the shapes of where the terrains meet up.

Here’s a sample blend of the terrains-joined-with-a-seam-terrain process: matchTerrainWithSeam.blend (615 KB)

Note that there will be some competition for space as the two surfaces are perfectly on top of each other (or nearly perfectly, depending on the placement of the vertices of each terrain object), which can result in some flickering or other unsightly results. You can mitigate that by tweaking the “Offset” value in the Shrinkwrap modifier, and/or deleting a few conflicting edges, and/or using an Object Projection for texture that both terrains share.