More slope fixes (aka sorry guys I made another quick SUGOI fix)
Another slopes fix branch!
This branch currently includes a fix for:
* Knuckles gliding into a slope while in 2D mode causes him to try to "climb" on air above them, if the original non-sloped height is higher. Unfortunately he still tries to grab onto places that he can't really climb on, but at least now it's on the slope itself and not in mid-air lol. This issue is encountered in SUGOI's Retro Hill Zone, if you want to check for yourselves.
* Bustable FOF-busting code for both players AND pushables not accounting for slopes
* (Unrelated to slopes): Fix FF_SHATTERBOTTOM FOFs acting like THZ goop when stood on; I added this fix as a bonus because I encountered it in a test map of mine for the bustables fix
(Other fixes may or may not appear here in the near future, I haven't decided yet. Don't wait on me to get in any further fixes before merging, that said)
See merge request !110
Last-minute NiGHTS exiting bugfix
One single-line fix concerning the end of NiGHTS maps. Extremely small, literally zero side effects here, the only reason I'm not committing directly to master (aside from ettiquette) is that I don't have the ability to do so.
* The NiGHTS drone had a single tic of visibility when you hit the goal, which is evident stepping frame by frame through http://gfycat.com/ComplicatedComposedAoudad (the contents of which may or may not make it into 2.2). This is no longer the case.
See merge request !100
Readme rewrite
Our readme.txt is outdated as hell, so I took it upon myself to rewrite it in Markdown. For the sake of simplicity, it links to the wiki for compile instructions. Feel free to commit to the readmerewrite branch if anything should be done differently.
See merge request !111
Optimisation of P_GetMobjGravity (relevant for slopes)
Cleaned up some performance issues in Skytop Zone (2.1.16: THE SUGOI UPDATE) arising from some inefficiencies with P_GetMobjGravity. FPS drops only occasionally to 34 now, which is a big improvement when I was frequently getting 27 in Salt's 15andahalf.exe.
(I also tested in a build of 2.1.16's first release candidate, and was getting drops to 16! So SOMETHING improved since then, but this was the major issue.)
See merge request !109
Also, the particles made via spindashing in shallow water are now located behind the player. This does move the running particles too, but that's okay.
