I'm working on a project that will use an enormous terrain generated from heightmaps, so I want to divide that terrain up into squares and only load the squares that are immediately visible by the viewer into memory. The problem is that even with "seamless" terrain, the edges of the squares are visible unless the height values for any two adjoining edges are identical, because no faces are created to span the difference in height between the two edges. I suppose that when I set the height values from the heightmaps I could check for vertices that are on the edge of a square and change it's height value to equal the heightvalue of it's counterpart vertice on the adjoining edge, but there must be a better way. I would be interested in any articles, tutorials, ideas, techniques, how-to's, or other resources for accomplishing this. Thanks.