* introducing the new friend, SH_FORCEHP (which is used as a bitmask to get the extra hitpoints of a force-shield user)
* P_DamageMobj now considers the unimplemented shield constants as well as the implemented ones.
* When not pressing any direction, you now go backwards by default - to emphasise that this is primarily for defensive, not offensive, purposes.
* The camera can now handle the player going backwards without them going completely off-screen.
* Fixed some overzealous checks.
* The spinfire ring is now capable of damaging enemies. (god, what a terrible hack this is)
* When ground pounding, you now bounce off the floor a little bit to make the ability less spammable.
* The Dodge Dash
* Allows you to dash - no control, no falling, no key response - for 2 + (number of extra shield hitpoints) tics.
* If you're holding movement keys down, you dash in the direction you're holding - otherwise, you dash directly forward.
* You're spinning (spindash spin, not jump spin) until your dash is over, then your momentum is cut down significantly and you end up in falling frames.
* It may not necessarily be super useful for Sonic, but it helps the other characters.
* http://gfycat.com/BogusFailingFritillarybutterfly
* http://gfycat.com/PoliticalIdealisticBallpython (outdated speed, shows any direction)
* Camerascale, shieldscale, height and spinheight are now player attributes which are set to the skin attribute on skin change, not read directly from the skin.
* P_GetPlayerHeight and P_GetPlayerSpinHeight are now macros instead of functions.
* Extra protection against switching to a locked skin.
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.
* Fixed bug where being pushed off a platform whilst charging a spindash would leave you in your charging frames instead of your rolling ones when you hit the ground (http://gfycat.com/MassiveThreadbareItalianbrownbear for how it works now, http://gfycat.com/MarvelousEnlightenedAuk is how it used to work)
* Fixed bug where spindashing on top of a bubble spawnpoint led to you being able to move around in spindash frames (no gif since obvious desired behaviour is obvious)
* Spindash animation speeds up the faster you'll shoot off.
* The spin charging mechanism is now scale-independent, and only multiplies by scale when shooting off - less FixedMul calls, and potentially deals with weird quirks of changing scale whilst spindashing that nobody's discovered because there's no place to find that in the main game!
Also:
* Climbing animation defaults to rolling instead of walking, because what.
* MF_AMBUSH is now MF2_AMBUSH, because it's something you turn on in a map editor, not with a SOC definition.
* Where MF_AMBUSH was is now MF_PAPER.
* MF_PAPER accesses all the stuff I did previously in this branch...
* ...as well as turn on paper-thin collision detection between mobjs, which I've gotten working but isn't perfect but it's still good enough for non-solid objects!!
I DID make some steps towards re-implementing PIT_CheckThing for solids only in order to replace the hack long-term and hopefully use less CPU, but is currently disabled via #if 0 since I'm not comfortable changing the function signature of P_CheckPosition right now.