scaleDenominator method
The map scale denominator at zoom
and screenPPI
.
This is a nominal scale denominator that may be accurate only in some positions like along the equator or a meridian depending on a projection.
By default screenPPI
of ~ 90.7 ppi is used (based on a screen pixel of
0.28 mm defined by OGC). Another common value is 96 ppi.
Implementation
@override
double scaleDenominator(
int zoom, {
double screenPPI = screenPPIbyOGC,
}) =>
pixelGroundResolution(zoom) * screenPPI / 0.0254;