File:Latitude and longitude graticule on a sphere.svg

    depicted with perspective projection

    viewer distance from center: 10r
    line distancd: 10°
    line width: 2°
    axial tilt: 37.5°
    rotation: 7.5°
    base color: #22326b

    plotted with several adapted cubic bezier-curves
    The plotcurves were calculated by some fancy python code. The bezier-curve
    controlpoints are placed on tangents of the function-curve. They are
    furthermore positioned in a way to minimize the average quadratic distance
    between the bezier-curve and the function. This gives an accuracy, so that
    the deviation is in no point greater than 0.00001.

    about: http://commons.wikimedia.org/wiki/Image:Sphere_wireframe_10deg_10r.svg
    source: http://commons.wikimedia.org/
    rights: GNU Free Documentation license,