Return air instead of __reserved__ when reading non-cuboid clipboard

[SirYwell]

Overview

Fixes #3065

Description

Returning the __reserved__ block state results in clipboards containing that block state, means they can't be loaded by other tools correctly and FAWE won't place air correctly.

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[dordsor21]

Can we potentially add a flag somewhere for allowing the reserved? If we set a clipboard within FAWE it might be wanted not to set outside the original copy region, but still set air within. Presumably this is also an issue for the other FAWE implementations as well?

[SirYwell]

Can we potentially add a flag somewhere for allowing the reserved? If we set a clipboard within FAWE it might be wanted not to set outside the original copy region, but still set air within.

This just mirrors the behavior of WE. Manually checking if the point is in the region when needed sounds more appropriate.

Presumably this is also an issue for the other FAWE implementations as well?

It seems like WorldCopyClipboard will just return the actual blocks outside of its region, so that's wrong in a different way. The memory clipboard seems to work correctly from a quick test, not sure why though.

[dordsor21]

Can we potentially add a flag somewhere for allowing the reserved? If we set a clipboard within FAWE it might be wanted not to set outside the original copy region, but still set air within.

This just mirrors the behavior of WE. Manually checking if the point is in the region when needed sounds more appropriate.

We won't necessarily have the selection when pasting - it could have changed between the copy and paste, or have been made before a restart

Presumably this is also an issue for the other FAWE implementations as well?

It seems like WorldCopyClipboard will just return the actual blocks outside of its region, so that's wrong in a different way. The memory clipboard seems to work correctly from a quick test, not sure why though.

memory optimized doesn't "store" air so I believe would assume reserved is just normal air. CPU optimized is potentially problematic as it'd read a char of 0 from the array

[SirYwell]

We won't necessarily have the selection when pasting - it could have changed between the copy and paste, or have been made before a restart

Hm, that's an interesting scenario. I guess SimpleRegion always returning a CuboidRegion is wrong then in first place, and we need to somehow improve on that?

[dordsor21]

Hm, that's an interesting scenario. I guess SimpleRegion always returning a CuboidRegion is wrong then in first place, and we need to somehow improve on that?

Yeah potentially some more thought to that. I do think it's a feature to allow "non-rectangular" clipboards to have air without overwriting a selection