xp bug :D

[Stirling.]

is this a bug? Can someone explain what happened

When I press TAB I see my xp normally, but on the hud is reset

[Kepar]

Yep it's a bug.

[Reborn]

Always after around 65k exp gained, you get to -600~xp on hud

[RedBaird]

The ET authors probably didn't forsee xp-saving mods.  

[FireWienie]

Makes sense, I was about to file a complaint when I got negative xp

[CheepHeep]

Haha lst tome that happened to me was like 6years ago xD. Was banned from their servers after a while for another reason lol.

[Radoria]

Not really a bug as much as a design feature. Can save memory by using a smaller container. The HUD exp is stored as a 16 bit integer. It'll reset every 2¹⁶ or 65,535. If they would have used a 32 bit integer instead, it would reset at 2³² or 4,294,967,295.

[RedBaird]

Not really a bug as much as a design feature. Can save memory by using a smaller container. The HUD exp is stored as a 16 bit integer. It'll reset every 2¹⁶ or 65,535. If they would have used a 32 bit integer instead, it would reset at 2³² or 4,294,967,295.

I figured something like that.  The mystery to me is why it shows negative numbers for a while after it overflows the 64k.  2s-complement won't explain it, else they would need 4 bytes to express the 64k.  I suspect that whatever operator they used to increment the number uses an intermediate variable of more than 2 bytes which it perhaps then reduces to 2 bytes BCD for display.  The overflow bit is taken to be a negative sign.  

[Stirling.]

thank you for your answers

[Olykiller]

Negative XP gives me nightmares