Actually here's a similar demo I put together in 2017 using heightmap only .. it's low-res, stitching together higher-altitude DEMs, but actually fairly perform

Actually here's a similar demo I put together in 2017 using heightmap only .. it's low-res, stitching together higher-altitude DEMs, but actually fairly performant without any trickery. You can zoom in on a section by drawing on the rendered tile on the left. https://codepen.io/theprojectsomething/details/rmmePG https://codepen.io/theprojectsomething/details/rmmePG