1. A process for optimizing a tile mesh for a surface in a level-of-detail hierarchy, comprising: obtaining a plurality of elevation values for an elevation grid of the surface; downsampling the elevation grid to a resolution based on a minimum edge size for triangles of the tile mesh as determined by a level-of-detail parameter; encoding the elevation grid into a linearized quadtree of virtual nodes; iteratively optimizing the quadtree according to an adaptive sampling pattern based on one or more prioritized split tests; and converting the optimized linearized quadtree into a tile mesh.