Object collision check

//Custom Glider Script By TSDude
//A lua based version of an air glider inspired by chi.miru's air glider wad on MB.

//NOTES:
//1) Checking for "P_IsObjectOnGround" and "P_IsObjectInGoop" is not used on the player, this is because the player is often unable to interact with the ground,
//when using the glider. Hence why their interaction is done indirectly through checking if the glider touching the ground.
//2) If you plan on making or using different sprites for the air glider, make sure that you modify the vertical offsets of those sprites. That way you can
//make it look like the player is hanging off of an object rather than cling their whole body to one.

freeslot (
"MT_GLIDESPAWNER",
"MT_VULTUREGLIDER",
"S_GLIDE_SPAWN",
"S_VULTURE_SPAWN",
"S_VULTURE_MOVE",
"S_VULTURE_DIE"
)

mobjinfo[MT_GLIDESPAWNER] = {
	doomednum = 455,
	spawnstate = S_GLIDE_SPAWN,
	spawnhealth = 1,
	reactiontime = 8,
	deathstate = S_XPLD1,
	speed = 2,
	radius = 16*FRACUNIT,
	height = 48*FRACUNIT,
	dispoffset = 0,
	mass = 100,
	flags = MF_SPECIAL|MF_NOBLOCKMAP|MF_NOGRAVITY
}

mobjinfo[MT_VULTUREGLIDER] = {
	doomednum = -1,
	spawnstate = S_VULTURE_SPAWN,
	spawnhealth = 1,
	reactiontime = 8,
	deathstate = S_VULTURE_DIE,
	speed = 2,
	radius = 16*FRACUNIT,
	height = 16*FRACUNIT,
	dispoffset = 0,
	mass = 100,
	flags = MF_NOGRAVITY|MF_FLOAT|MF_NOCLIPTHING
}

//You can modify the values in these states to your hearts content.
//For example, changing the A_Thrust value from "20" to a higher number, would make the glider move faster,
//whereas a lower value would make the glider move slower.

states[S_GLIDE_SPAWN] = {SPR_VLTR, TR_TRANS50|A, 1, nil, 0, 0, S_GLIDE_SPAWN} //Glide Spawner object spawn state
states[S_VULTURE_SPAWN] = {SPR_VLTR, A, 1, nil, 0, 0, S_VULTURE_SPAWN} //Glider object spawn state
states[S_VULTURE_MOVE] = {SPR_VLTR, A, 1, A_Thrust, 15, 1, S_VULTURE_MOVE} //This state determines the horizontal speed of the air glider.
states[S_VULTURE_DIE] = {SPR_VLTR, A, 1, nil, 0, 0, S_XPLD1} //Death state of air glider.

local function SpawnGlider(mobj)
	A_SpawnObjectRelative(mobj, (64*65536)+-64, (100*65536)+MT_GLIDESPAWNER) //Spawns a Glide Spawner object above the player at the start of a level.
end
addHook("MobjSpawn", SpawnGlider, MT_PLAYER)

local startglide = 0

local function GlideStart(gldr, plyr)
	for player in players.iterate
		A_SpawnObjectRelative(plyr, (0*65536)+0, (0*65536)+MT_VULTUREGLIDER) //Spawn the air glider relative to the player.
		A_SetObjectTypeState(plyr, 1965, MT_VULTUREGLIDER+(0<<16)) //Set the air glider's state to its movement state.
		P_ResetPlayer(player) 	//Necessary for making sure that the player cannot damage enemies while gliding, thus they are not semi-invulnerable.
		player.pflags = $1 | PF_ITEMHANG //Player is hanging from an object.
		A_SetObjectTypeState(gldr, 49, MT_PLAYER+(0<<16)) //Put the player into their hanging state.
		startglide = 1
	end
end
addHook("TouchSpecial", GlideStart, MT_GLIDESPAWNER)

addHook("ThinkFrame", do
	for player in players.iterate
		if startglide == 1
			A_FindTarget(player.mo, 418, 0) //Player finds the air glider object. You can change the target if necessary.
			A_CapeChase(player.mo, 0, 0) //Player's position will continuously be set to the air glider's position.
			A_SetObjectFlags(player.mo, MF_NOGRAVITY, 2) //Player has no gravity.
			A_SetObjectFlags(player.mo, MF_FLOAT, 2) //Player can float.
		else
			A_SetObjectFlags(player.mo, MF_NOGRAVITY, 1) //Player has gravity.
			A_SetObjectFlags(player.mo, MF_FLOAT, 1) //Player can no longer float. :(
		return
		end
	end
end)

local aboveceiling = 0

local function GlideThinker(mobj)
	for sector in sectors.iterate
		if (mobj.subsector.sector.ceilingheight < mobj.height+(mobj.z+2*FRACUNIT))
			aboveceiling = 1
		end
	end
	for player in players.iterate
		mobj.angle = player.mo.angle //Sets the air glider's angle to the player's angle, so whenever the player turns, the glider turns.
		//The glider's vertical momentum values can be changed if necessary.
		if mobj.momz > 10*FRACUNIT
			mobj.momz = 10*FRACUNIT //Air glider's upward vertical momentum has been set to not exceed "10*FRACUNIT".
		elseif mobj.momz < -10*FRACUNIT
			mobj.momz = -10*FRACUNIT //Air glider's downward vertical momentum has been set to not exceed "-10*FRACUNIT".
		end
		if player.cmd.forwardmove > 0 //Is the player pressing the forwardmove key?
			A_ZThrust(mobj, 1, 0) //If so then make the glider move upwards.
		elseif player.cmd.forwardmove < 0 //Is the player pressing the backwardmove key?
			A_ZThrust(mobj, -1, 0) //If so then make the glider move downwards.
		end
		if (player.pflags & PF_USEDOWN) //Is the player pressing the spin button while using the glider?
			A_Thrust(mobj, 30, 1) //GIVE HIM SOME BOOST!!!
			player.boost = 1
		else
			player.boost = 0
		end
		if startglide == 1 then
			if (player.pflags & PF_JUMPDOWN) //Has the player jumped?
			or P_IsObjectOnGround(mobj) or P_IsObjectInGoop(mobj) //Using the glider mobj instead of the player's, see notes.
			or P_PlayerInPain(player) //Did the player get hurt?
			or player.exiting == 1 //Has the player finished the level?
			or (player.playerstate & PST_DEAD)
			or aboveceiling == 1
				//If any of these are true then stop using the air glider.
				A_ForceStop(player.mo, 1)
				if not P_PlayerInPain(player) and not (player.playerstate & PST_DEAD) then
					if player.boost == 0
						A_Thrust(player.mo, 10, 1)
					elseif player.boost == 1
						A_Thrust(player.mo, 20, 1)
						player.boost = 0
					end
				end
				P_KillMobj(mobj, mobj, mobj)
				startglide = 0 //Reset "startglide" value
				aboveceiling = 0
				if (player.pflags & PF_ITEMHANG) //Was the player hanging onto an object?
					player.pflags = $1 ^^ PF_ITEMHANG //Reset the player flag for hanging on an object.
				end
			end
		end
	end
end
addHook("MobjThinker", GlideThinker, MT_VULTUREGLIDER)