MIN_VALID_M 0, or -1500

[tyrauber]

Instead of processing the terrain tiles to remove the oceans, wouldn't it make more since to handle that zeroing out of the ocean in software? Couldn't we just set height-tile MIN_VALID_M to 0, or -1500 (to account for the Dead Sea), and zero out any height less than the MIN_VALID_M?

maplibre-contour/src/height-tile.ts

Line 3 in 8962d7c

const MIN_VALID_M = -12000;

Additionally, the values could be passed as options, so that this library could work on other planets. 😂

[tyrauber]

Ok. Meters not feet. Also, setting the MIN_VALID_M is not enough. You need to use that value here:

maplibre-contour/src/height-tile.ts

Line 21 in 8962d7c

this.height = height;

For example:

 this.height =  defaultIsValid(height) ? height : 0;

Which, with 500 to account for the Dead Sea, produces the following behavior:

[msbarry]

That would work! Want to make a PR?

[tyrauber]

Actually! @msbarry, the library already supports this through filters. At least for contours!

filter: [">", ["get", "ele"], 0],.

Here is ele filter at 2200 ft.

Unfortunately, this same approach doesn't work for hillshade type (ele filtered at 2200 as well in the above image). It looks like the maplibre hillshade code doesn't accommodate filters.