Converting "reaper object" pointers to strings and back

[juliansader]

Does anyone perhaps know if it is possible to convert "reaper object" pointers (to MIDI editors or takes, for example) to strings and back?

This is to save the pointers as ExtState strings that can be recalled later.

Turning a pointer into a string is easy: tostring(editor) gives something like "userdata: 0000DA3EF". But can this string be turned back into a pointer?

[X-Raym]

I don't think there is a reaperobject = toreaperobject("string") kinf of function,

A dirty solution would be to chck your string against all other object of the same type also converted to string, and if there is a match, then get the object.

[planetnine]

Might be a useless exercise anyway, saving them in ExtState, as the IDs of object pointers change between project instantiations.

I saved take GUIDs in Project Marker descriptions so that they reconnected after project reloads. There was no Project ExtState at the time and I needed an "Item Marker" script to track the markers to user moved items -this allowed marker<==>take association data to survive project reloads and even be stored in REAPER's marker/region manager

If I read your intentions correctly, Julian, I'd go for saving GUIDs as strings in ExtState/ProjectExtState and building back to (newly ID'd) objects from there.

Hope this is relevant and we're not at cross-purposes



>

[Xenakios]

Originally Posted by planetnine

Might be a useless exercise anyway, saving them in ExtState, as the IDs of object pointers change between project instantiations.

Not just "might", serializing and deserializing pointers is in 99% of cases useless to do. (I've maybe once done that in some C++ code, because the code didn't depend on the pointers being the same later when the program was quit and restarted. And I think I later changed that to use a "unique identifier" system anyway.)

[juliansader]

Thanks for the replies!

Originally Posted by X-Raym

A dirty solution would be to chck your string against all other object of the same type also converted to string, and if there is a match, then get the object.

Would it be possible to access a list of all objects of type "HWND midieditor"? (I doubt it, but I hope so!)

The reason why I asked about saving pointers as ExtStates, is so that I can access all pointers to all MIDI editors, in order to apply and coordinate actions (such as zooming) between multiple editors.

[Xenakios]

Originally Posted by juliansader

The reason why I asked about saving pointers as ExtStates, is so that I can access all pointers to all MIDI editors, in order to apply and coordinate actions (such as zooming) between multiple editors.

This would appear to be a legitimate use case for serializing pointers/object handles, you just need to take care the pointers/handles don't stick around in the persistent storage, causing confusion after Reaper has been quit and restarted.

[juliansader]

In C++, converting the "userdata" to a HWND requires nothing more than a typecast!

It seems that, in REAPER's ""userdata: 0000000590C44"", the hex numbers are the actual address, so this works:

void* JS_CastAddressToHWND(int address)
{
    return (HWND)address;
}

[Xenakios]

Originally Posted by juliansader

In C++, converting the "userdata" to a HWND requires nothing more than a typecast!

It seems that, in REAPER's ""userdata: 0000000590C44"", the hex numbers are the actual address, so this works:

void* JS_CastAddressToHWND(int address)
{
    return (HWND)address;
}

Be extremely careful with that kind of stuff. ints are 32 bit, HWNDs and void*'s (and pointers in general) are 64 bit in 64 bit builds.