SYNOPSIS:
    coordinate: Eccet uses multiple coordinate systems.

DESCRIPTION:
    As eccet can do multirendering, you usually have mutiple
    coordinate systems to work with at the same time.

    Voxel fields usually induce an intrinsic coordinate system that
    is defined by their voxel numbers in all of their dimensions.
    A voxel field that has an inplane resolution of 512x320 with
    200 slices thus induces a _local_ coordinate system win which
    coordinates are integer vectors in the range [0-511], [0-319], [0-199].
    When subvoxel precision is used, the vectors are double and
    ranges can be [0-512[, [0-320[, [0-200[. Voxel centers are assumed
    to be at x.5, y.5, z.5.
    [0-511[,

    As these local coordinates are not necessarily isotropous, a global
    coordinate system is introduced that is always isotropous and has
    a fixed mapping to real world sizes. 1 unit of the global coordinate
    system usually maps to 1mm, unless explicitly noted otherwise.
    (Some applications, like microtomography or laser-fluorescence
     microscopy work on a m scale, so using mm scaled coordinate
     systems would not be appropriate).

    Most Eccet commands take coordinates as appropriate for the object
    in question. Commands manipulating global objects like cameras,
    cutplanes, tristrips and splines work in the global coordinate
    system, while commands manipulating volumes usually work in
    the coordinate system local to the current volume.

SEE ALSO:
    camera, cutplane, tristrip, spline, volume, field
