Note about A_SkelMissile: The direct change of the missile's position was changed to use SetOrigin. If this is later supposed to be portal-aware, such direct coordinate changes are a no-go to ensure that everything is properly maintained.
This contains some advance work for handling line-to-line portals in A_PainShootSkull.
This function is special because it performs a map check itself instead of using one of the common functions from p_map.cpp, like most of the rest of the game code.
This commit is just preparation for upcoming changes to completely encapsulate the coordinate info in AActor because I'm going to have to work with an altered version of actor.h that cannot be committed without breaking the engine.
With this file present in the repo before work is started the changes can be committed piece by piece.
There is no need to close (and thus deallocate) console window explicitly
This will be done by autorelease pool in application controller event loop
OS X with GC and/or ARC was not affected by this issue
Older versions like 10.4 or 10.5 crashed because of double deallocation
Because frac variable has fixed_t type it must be compared with fixed one
Test case: try to break stained glass windows or open door at the beginning of Hexen's MAP01
* since we can trivially decide whether a line crosses the trace behind the end point from checking the return value of P_InterceptVector, there is no need to add those to the list of intercepts as they get discarded anyway in t
* maxfrac is always FRACUNIT so there's no need to waste some variable for a constant value.
Updated version of Return to Hadron (dated 2016.01.03) has new version of E1M9: Prototype
This map requires vanilla's P_PointOnLineSide() function to avoid issue with sleepy shotgun guys
http://forum.zdoom.org/viewtopic.php?t=49544
* the sight checking code needs to be as precise as possible and should not depend on some old semi-broken routines. (This is more a precision issue of these routines - P_PointOnDivlineSide removes the lower 8 bits of each value - than having an issue with returning the wrong side in some cases.)
* for slope creations it is flat out wrong to use the old routines at all.
* also ignore this in the modern (box-shaped) case of FPathTraverse::AddLineIntercepts. This functionality is new to ZDoom and therefore not subject to compatibility concerns.
* the line-to-line teleporter. It seems the hideous fudging code was just there to work around the design issues of these functions, so let's better not ever call them here in the first place.
* A_PainShootSkull: Its usage here does not depend on these issues.
* P_ExplodeMissile: New code exclusive to ZDoom.
* FPolyObj::CheckMobjBlocking
All occurences in p_map.cpp have been left alone although most of them probably won't need the compatibility option either.
