How to create a 100% custom map projection?

[Exciteomapo]

Hello cartographers and mathematicians.

Can anyone help me get to grips with creating a 100% custom map projection? I want to be able to define these things:

• The formula used to unwrap/project the map, in a standardised notation (possibly Python).
  The position of datums - such as where the map splits and location of fixed point(s) such as poles (in the case of Earth).

I am speculating that any map projection can be generated with these two things, and that there's probably already a way of getting a computer to do it for me. That might be completely wrong.

I feel like QGIS or MatLab might be a good tool for this. G.Projector was looking viable, but I don't think it lets you define your own rules for the projections.

Thanks

[Atarimaster]

I don’t know if this is helpful to you, but…

I’ve mentioned d3js before, in other threads. Since it renderes map projections from formulae written in JavaScript and already offers a lot of different projections (see here) which you can use to figure out how it works, it might be worth looking at.
Alas, it »only« creates vector graphic images. There is a raster reprojection plugin but currently, it’s labeled as demo, »not ready for production«.

Then, there is a Windows application called Vimage. It’s able to open RTA (Reduced Transliteration Assembler) files which describe the projections, but of course, Assembler might not be what you want… Worse, while its german documentation is extensive, there’s only sparse information in English, and it’s quite expensive, too (600 Euro).

Regards,
Tobias

[daan]

Can anyone help me get to grips with creating a 100% custom map projection? I want to be able to define these things:

• The formula used to unwrap/project the map, in a standardised notation (possibly Python).
  The position of datums - such as where the map splits and location of fixed point(s) such as poles (in the case of Earth).

I am speculating that any map projection can be generated with these two things, and that there's probably already a way of getting a computer to do it for me.

You would also need a complete description of the the path that defines the projection’s perimeter. That is trivial for some projections in some aspects, but can get quite complicated in the general case.

Good luck!
— daan