Slope — per-pixel terrain steepness via Horn's method (gdaldem's slope algorithm), computed in pure
JS on the decoded grid. unit:'degrees'|'percent'; zFactor scales elevation before the gradient
(vertical exaggeration / unit conversion, e.g. feet→metres).
Slope — per-pixel terrain steepness via Horn's method (gdaldem's slope algorithm), computed in pure JS on the decoded grid.
unit:'degrees'|'percent';zFactorscales elevation before the gradient (vertical exaggeration / unit conversion, e.g. feet→metres).