Unreal engine 4 wiki
If you're in the Northern Hemisphere, the equator has a northing value of 0 meters. All easting values will be greater than this central value, and all westing values will be lower, but all values will be positive. This central meridian is an arbitrary value convenient for avoiding any negative coordinates. Specific assumptions are necessary to make sure that all coordinates are positive.Įach 6°-wide UTM zone has a central meridian located by definition at X=500,000 meters.
This is a Cartesian coordinate system, but on top of the XYZ coordinates, we need a Zone and Hemisphere identifier to define the origin. This CRS divides Earth into 60 parts, or zones, and projects each of these north/south-oriented zones using a cylindrical projection that is tangent to the central meridian of each zone. One of the most frequently used projections is the Mercator projection, which has several variants.įor instance, we have the Universal Transverse Mercator projection that is widely used in the Simulation Industry. Most basic projections are using planar, conical or cylindrical shapes. There are different ways to project a sphere to a plane, so there are lots of possible map projections, with more or less deformation, depending on the area mapped. This is what we have always used when looking at paper maps. Y Axis is orthogonal to the former two axes.Ī projected coordinate system is a Geographic Coordinate System in which the planet has been "flattened" using a map projection. Z Axis aligns with the Earth's axis of rotation. X Axis points to the Equator/Prime Meridian (Greenwich) intersection.