Slopewall transfer
As @Nev3r wants. Go along a slope, hit a wall? LAUNCH! Well, I mean. He wants it slightly less weak. I have already made it less weak than P_SlopeLaunch.
Also also I made the trail that goes behind the player when they're rolling take into account vertical momentum as well as horizontal, so that being launched directly up didn't leave you trailless.
Test with <root>/!LatestSRB2Files/srb2win_branch_transfer.exe and <root>/Nev3r/ACZMaster.wad (roll down slope directly in front of you).
See merge request !66
* Seriously reworked a lot of stuff behind the scenes, thanks to Red's comments.
* More consistent behaviour.
* Launching power is now scaled to the slope's angle relative to the wall you hit, so no massive launches when you hit the side of a steep slope.
* The code is a lot messier and the function name doesn't make any sense any more, so I need to clean that up in the morning.
* Need to figure out how to prevent tiny launches that uncurl you when spindashing up against walls.
* Spindashing trails now takes into account vertical momentum as well as horizontal - it was stupid not seeing your spintrail just because you weren't moving very fast horizontally!
No exe uploaded because it's almost 2am.
Spindash dust
Charging a spindash kicks up dust, we all know this feature was dying to get in at some point. Bubble and flame forms of spin dust are included from FSonic, for underwater and elemental respectively.
Oh, and as a bonus I reorganised the spindash/spinning/other ability2 stuff code to look a bit neater and more organised.
New resources:
* MT_SPINDUST - the object
* S_SPINDUST1 to 4 - the normal form's states
* S_SPINDUST_BUBBLE1 to 4 - the bubble form's states
* S_SPINDUST_FIRE1 to 4 - the bubble form's states
* SPR_DUST - the normal form's sprite set (uses frames A to D, just pinch FSonic's sprites really)
* SPR_FPRT - the flame form's sprite set (frame A only)
SF_NOSPINDASHDUST disables spindash dust for a character
See merge request !52
* Space sector support complete, bounds of drowning now altered slightly.
* Knuckles climb now has symmetrical slope support for both normal and reverse gravity.
* All slope-determining topheight and bottomheight code is now identical in form.
* Camera postimages now support slopes properly.
Moved the handling of P_PlayerInSpecialSector to P_PlayerAfterThink from P_PlayerThink.
* This allows the player to get hurt on sloped lava surfaces that are moving downwards.
* Also prevents the player from standing on death pits for 1 tic.
* Prevents the player moving 1 extra tic's worth of movement of pain when hit by sector.
* Thankfully, no consequences re conveyors.
* Like, the only consequences I've found have been positive. However, this DOES need to be thoroughly investigated before it can be allowed anywhere near Next itself.
(neither does P_CanRunOnWater, but I don't think it's necessary to make that check more complicated as you probably shouldn't be able to waterrun up steep surfaces anyways)
