Tile2R function

simple utility to offset and scale XY coordinates with respect to the center

Tile2R(points, center)

Arguments

• points: XY coordinates returned by e.g. LatLon2XY
• center: XY coordinates of center returned by e.g. LatLon2XY

Details

mainly used for shrinking the size of a tile to the minimum size.

Returns

list with X and Y pixel values

Author(s)

Markus Loecher

Examples

latR <- c(34.5,34.9);
 lonR <- c(-100.3, -100);
 lat.center <- 34.7;
 lon.center <- -100.2;
 zoom = 10;
 ll <- LatLon2XY(latR[1], lonR[1], zoom);#lower left corner
 ur <- LatLon2XY(latR[2], lonR[2], zoom );#upper right corner
 cr <- LatLon2XY(lat.center, lon.center, zoom );#center
 ll.Rcoords <- Tile2R(ll, cr);
 ur.Rcoords <- Tile2R(ur, cr);