cad3d and export from Aven should produce identical .dxf files

[Duncan Collis]

There are two ways to produce .dxf files from a .3d file, producing different results:

cad3d produces a .dxf file which preserves the absolute co-ordinates used in the .3d file

export from Aven produces a .dxf file in which the origin of the co-ordinate system has been moved (probably to the centre of the network, haven't checked...)

Both are valid .dxf files, but the difference seems arbitrary and confusing. Perhaps both methods should give a choice of outputs.

[Olly Betts]

This wasn't really intended - aven just feeds coordinates from its internal structures into the export code, and it happens to have moved the origin to the centre of those coordinates (though that may not be the same as the centre of what appears in the DXF export).

[bc1fac5] (which will be in 1.2.8) adds the ability to choose whether Aven's DXF export has the full coordinates or the origin at the lower left - origin at the lower left seems more useful than at the centre, but it's easy to change this, or to offer both (if both are actually useful).

Currently aven and cad3d have parallel versions of what was originally the same code, which isn't very sensible, so I'm planning to deprecate cad3d in favour of the aven export, and possibly provide a way to work the aven export from the command line if people would find that useful. Hence I'm not planning to add this choice to cad3d too, so closing this ticket.