CPP Coordinate System

A CPP (Carte Parallelo-Grammatique Projection) system is a local system. The origin of the system must be defined in latitude/longitude decimal degrees.

The conversion from of a point from latitude/longitude to CPP is:

${\text{newpoint}}_{x}=R*{\Big (}{\text{point}}_{\text{longitude}}-{\text{origin}}_{\text{longitude}}{\Big )}*\cos {\Big (}{\text{origin}}_{\text{latitude}}{\Big )}$

$\ {\text{newpoint}}_{y}={\text{point}}_{\text{longitude}}*R$

The conversion of a point from CPP to latitude/longitude is:

${\text{newpoint}}_{\text{longitude}}={\frac {{\text{origin}}_{\text{longitude}}+{\text{point}}_{x}}{R*\cos {\big (}{\text{origin}}_{\text{latitude}}{\big )}}}$

$\ {\text{newpoint}}_{\text{latitude}}={\frac {{\text{point}}_{y}}{R}}$

R = 6378206.4 m. (Clarke 1866 major spheroid radius)

See also

• Coordinate Systems