ZDoom

[quote="_mental_"]I guess you need [url=https://github.com/coelckers/gzdoom/blob/d6396e79fba71de0167e618d265c1b91f7930f9d/wadsrc/static/zscript/level_compatibility.zs#L1433]LevelCompatibility.OffsetSectorPlane()[/url] method. As for the initial report, correctly used or not, the crash must be to fixed.[/quote]

This. The compatibility handler should only use its own interface.

What should I do then? Those ceilings in particular need to be adjusted somehow or that map will never allow for 100% kills.

You do that from the compatibility handler? No wonder it crashes, at that point the level isn't fully initialized, and adding checks for that to every function imaginable is way too much work. In particular the lines array in the sector is still empty at this time, because line properties can be changed from compatibility handlers, including the sector reference.
These functions are not for raising the ceiling but for creating a ceiling movement thinker.

If I could I'd just block off access to the level there, but that'd render the class useless. Unfortunately that exposes all of Level's functions to the handler, even though most of them would probably crash.

double val = 64;
level.CreateCeiling(level.sectors[3044], Ceiling.ceilRaiseByValue,	level.lines[28656], val, 0, val);
level.CreateCeiling(level.sectors[245], Ceiling.ceilRaiseByValue,	level.lines[28664], val, 0, val);
level.CreateCeiling(level.sectors[990], Ceiling.ceilRaiseByValue,	level.lines[28660], val, 0, val);
level.CreateCeiling(level.sectors[3045], Ceiling.ceilRaiseByValue,	level.lines[28652], val, 0, val);
level.CreateCeiling(level.sectors[3239], Ceiling.ceilRaiseByValue,	level.lines[28327], val, 0, val);
level.CreateCeiling(level.sectors[3251], Ceiling.ceilRaiseByValue,	level.lines[28335], val, 0, val);
level.CreateCeiling(level.sectors[3235], Ceiling.ceilRaiseByValue,	level.lines[28331], val, 0, val);
level.CreateCeiling(level.sectors[3243], Ceiling.ceilRaiseByValue,	level.lines[28323], val, 0, val);

[code]double val = 64;
level.CreateCeiling(level.sectors[3044], Ceiling.ceilRaiseByValue, level.lines[28656], val, 0, val);
level.CreateCeiling(level.sectors[245], Ceiling.ceilRaiseByValue, level.lines[28664], val, 0, val);
level.CreateCeiling(level.sectors[990], Ceiling.ceilRaiseByValue, level.lines[28660], val, 0, val);
level.CreateCeiling(level.sectors[3045], Ceiling.ceilRaiseByValue, level.lines[28652], val, 0, val);
level.CreateCeiling(level.sectors[3239], Ceiling.ceilRaiseByValue, level.lines[28327], val, 0, val);
level.CreateCeiling(level.sectors[3251], Ceiling.ceilRaiseByValue, level.lines[28335], val, 0, val);
level.CreateCeiling(level.sectors[3235], Ceiling.ceilRaiseByValue, level.lines[28331], val, 0, val);
level.CreateCeiling(level.sectors[3243], Ceiling.ceilRaiseByValue, level.lines[28323], val, 0, val);
[/code]

Even this crashed though, with the same thing. Lines was turning out null.

It shouldn't be able to crash there, unless the function was used in a catastrophically wrong way. And therefore I can't fix it without seeing what was done wrong here.

I guess you need [url=https://github.com/coelckers/gzdoom/blob/d6396e79fba71de0167e618d265c1b91f7930f9d/wadsrc/static/zscript/level_compatibility.zs#L1433]LevelCompatibility.OffsetSectorPlane()[/url] method. As for the initial report, correctly used or not, the crash must be to fixed.

What are you trying to do? You cannot call map thinker functions from the compatibility code. Please post your code.

I'm currently attempting to create compatibility with Hellbound Map29 as several ceilings are too low, blocking cyberdemons from teleporting. However, if you set the line parameter to null, the game instantly crashes at a_ceiling.cpp, line 248 due to a null pointer.

CreateFloor, on the other hand, has a safeguard in place in the event it's null. CreateCeiling just assumes it's there.

Note, it doesn't do a VM abort, the game just outright closes out completely, instantly shutting down.