Position

• Position, for rendering, is calculated as a vector.
• Note that things are usually tiled with triangles to give an arbitrary degree of precision.
• Position is also calculated for physics.
• This is typically done as the centre of mass of the body being measured.
• In real physics, this can lead to problems.
• The centre of the earth is fair enough and the calculation for two body problems like the moon going around the earth works.
• However, for 3 body problems, the physics is not precise.
• There are also issues of bodies being differentially weighted, e.g. the watery bits are lighter than the iron core of the earth.
• However, the approximations work pretty well.
• (It's not just game developers who approximate.)