For me pd64 gives more chances of confusion than pdd or pdpd.
(...)
Starting with a new name of the app seems the most sane.
Funnily, my personal feeling is the opposite :-)
I feel that Pd64 clearly describes Pd working with 64 bit data.
I think that confusion with 64 bit architectures will become less present, since nowadays most (all?) major platforms are based on 64 bit CPUs. So "64 bit" is just a particular taste of CPUs, as in x86_64 or arm64, which has no direct impact from the user's point of view. If you want to work with 64bit-wide data on a 32bit PPC, you just need Pd64-PPC32, on arm64 it will be Pd64-arm64.
To me, "pdd" or "pdpd" really sound like different apps, which I find a bit strange (it's actually the same app, only different options).
I quite like Pd² or even Pd2, though.
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