Source code for pico-8 version of Celeste

celeste.lua

-- ~celeste~
-- matt thorson + noel berry

-- globals --
-------------

room = { x=0, y=0 }
objects = {}
types = {}
freeze=0
shake=0
will_restart=false
delay_restart=0
got_fruit={}
has_dashed=false
sfx_timer=0
has_key=false
pause_player=false
flash_bg=false
music_timer=0

k_left=0
k_right=1
k_up=2
k_down=3
k_jump=4
k_dash=5

-- entry point --
-----------------

function _init()
	title_screen()
end

function title_screen()
	got_fruit = {}
	for i=0,29 do
		add(got_fruit,false) end
	frames=0
	deaths=0
	max_djump=1
	start_game=false
	start_game_flash=0
	music(40,0,7)
	
	load_room(7,3)
end

function begin_game()
	frames=0
	seconds=0
	minutes=0
	music_timer=0
	start_game=false
	music(0,0,7)
	load_room(0,0)
end

function level_index()
	return room.x%8+room.y*8
end

function is_title()
	return level_index()==31
end

-- effects --
-------------

clouds = {}
for i=0,16 do
	add(clouds,{
		x=rnd(128),
		y=rnd(128),
		spd=1+rnd(4),
		w=32+rnd(32)
	})
end

particles = {}
for i=0,24 do
	add(particles,{
		x=rnd(128),
		y=rnd(128),
		s=0+flr(rnd(5)/4),
		spd=0.25+rnd(5),
		off=rnd(1),
		c=6+flr(0.5+rnd(1))
	})
end

dead_particles = {}

-- player entity --
-------------------

player = 
{
	init=function(this) 
		this.p_jump=false
		this.p_dash=false
		this.grace=0
		this.jbuffer=0
		this.djump=max_djump
		this.dash_time=0
		this.dash_effect_time=0
		this.dash_target={x=0,y=0}
		this.dash_accel={x=0,y=0}
		this.hitbox = {x=1,y=3,w=6,h=5}
		this.spr_off=0
		this.was_on_ground=false
		create_hair(this)
	end,
	update=function(this)
		if (pause_player) return
		
		local input = btn(k_right) and 1 or (btn(k_left) and -1 or 0)
		
		-- spikes collide
		if spikes_at(this.x+this.hitbox.x,this.y+this.hitbox.y,this.hitbox.w,this.hitbox.h,this.spd.x,this.spd.y) then
		 kill_player(this) end
		 
		-- bottom death
		if this.y>128 then
			kill_player(this) end

		local on_ground=this.is_solid(0,1)
		local on_ice=this.is_ice(0,1)
		
		-- smoke particles
		if on_ground and not this.was_on_ground then
		 init_object(smoke,this.x,this.y+4)
		end

		local jump = btn(k_jump) and not this.p_jump
		this.p_jump = btn(k_jump)
		if (jump) then
			this.jbuffer=4
		elseif this.jbuffer>0 then
		 this.jbuffer-=1
		end
		
		local dash = btn(k_dash) and not this.p_dash
		this.p_dash = btn(k_dash)
		
		if on_ground then
			this.grace=6
			if this.djump<max_djump then
			 psfx(54)
			 this.djump=max_djump
			end
		elseif this.grace > 0 then
		 this.grace-=1
		end

		this.dash_effect_time -=1
  if this.dash_time > 0 then
   init_object(smoke,this.x,this.y)
  	this.dash_time-=1
  	this.spd.x=appr(this.spd.x,this.dash_target.x,this.dash_accel.x)
  	this.spd.y=appr(this.spd.y,this.dash_target.y,this.dash_accel.y)  
  else

			-- move
			local maxrun=1
			local accel=0.6
			local deccel=0.15
			
			if not on_ground then
				accel=0.4
			elseif on_ice then
				accel=0.05
				if input==(this.flip.x and -1 or 1) then
					accel=0.05
				end
			end
		
			if abs(this.spd.x) > maxrun then
		 	this.spd.x=appr(this.spd.x,sign(this.spd.x)*maxrun,deccel)
			else
				this.spd.x=appr(this.spd.x,input*maxrun,accel)
			end
			
			--facing
			if this.spd.x!=0 then
				this.flip.x=(this.spd.x<0)
			end

			-- gravity
			local maxfall=2
			local gravity=0.21

  	if abs(this.spd.y) <= 0.15 then
   	gravity*=0.5
			end
		
			-- wall slide
			if input!=0 and this.is_solid(input,0) and not this.is_ice(input,0) then
		 	maxfall=0.4
		 	if rnd(10)<2 then
		 		init_object(smoke,this.x+input*6,this.y)
				end
			end

			if not on_ground then
				this.spd.y=appr(this.spd.y,maxfall,gravity)
			end

			-- jump
			if this.jbuffer>0 then
		 	if this.grace>0 then
		  	-- normal jump
		  	psfx(1)
		  	this.jbuffer=0
		  	this.grace=0
					this.spd.y=-2
					init_object(smoke,this.x,this.y+4)
				else
					-- wall jump
					local wall_dir=(this.is_solid(-3,0) and -1 or this.is_solid(3,0) and 1 or 0)
					if wall_dir!=0 then
			 		psfx(2)
			 		this.jbuffer=0
			 		this.spd.y=-2
			 		this.spd.x=-wall_dir*(maxrun+1)
			 		if not this.is_ice(wall_dir*3,0) then
		 				init_object(smoke,this.x+wall_dir*6,this.y)
						end
					end
				end
			end
		
			-- dash
			local d_full=5
			local d_half=d_full*0.70710678118
		
			if this.djump>0 and dash then
		 	init_object(smoke,this.x,this.y)
		 	this.djump-=1		
		 	this.dash_time=4
		 	has_dashed=true
		 	this.dash_effect_time=10
		 	local v_input=(btn(k_up) and -1 or (btn(k_down) and 1 or 0))
		 	if input!=0 then
		  	if v_input!=0 then
		   	this.spd.x=input*d_half
		   	this.spd.y=v_input*d_half
		  	else
		   	this.spd.x=input*d_full
		   	this.spd.y=0
		  	end
		 	elseif v_input!=0 then
		 		this.spd.x=0
		 		this.spd.y=v_input*d_full
		 	else
		 		this.spd.x=(this.flip.x and -1 or 1)
		  	this.spd.y=0
		 	end
		 	
		 	psfx(3)
		 	freeze=2
		 	shake=6
		 	this.dash_target.x=2*sign(this.spd.x)
		 	this.dash_target.y=2*sign(this.spd.y)
		 	this.dash_accel.x=1.5
		 	this.dash_accel.y=1.5
		 	
		 	if this.spd.y<0 then
		 	 this.dash_target.y*=.75
		 	end
		 	
		 	if this.spd.y!=0 then
		 	 this.dash_accel.x*=0.70710678118
		 	end
		 	if this.spd.x!=0 then
		 	 this.dash_accel.y*=0.70710678118
		 	end	 	 
			elseif dash and this.djump<=0 then
			 psfx(9)
			 init_object(smoke,this.x,this.y)
			end
		
		end
		
		-- animation
		this.spr_off+=0.25
		if not on_ground then
			if this.is_solid(input,0) then
				this.spr=5
			else
				this.spr=3
			end
		elseif btn(k_down) then
			this.spr=6
		elseif btn(k_up) then
			this.spr=7
		elseif (this.spd.x==0) or (not btn(k_left) and not btn(k_right)) then
			this.spr=1
		else
			this.spr=1+this.spr_off%4
		end
		
		-- next level
		if this.y<-4 and level_index()<30 then next_room() end
		
		-- was on the ground
		this.was_on_ground=on_ground
		
	end, --<end update loop
	
	draw=function(this)
	
		-- clamp in screen
		if this.x<-1 or this.x>121 then 
			this.x=clamp(this.x,-1,121)
			this.spd.x=0
		end
		
		set_hair_color(this.djump)
		draw_hair(this,this.flip.x and -1 or 1)
		spr(this.spr,this.x,this.y,1,1,this.flip.x,this.flip.y)		
		unset_hair_color()
	end
}

psfx=function(num)
 if sfx_timer<=0 then
  sfx(num)
 end
end

create_hair=function(obj)
	obj.hair={}
	for i=0,4 do
		add(obj.hair,{x=obj.x,y=obj.y,size=max(1,min(2,3-i))})
	end
end

set_hair_color=function(djump)
	pal(8,(djump==1 and 8 or djump==2 and (7+flr((frames/3)%2)*4) or 12))
end

draw_hair=function(obj,facing)
	local last={x=obj.x+4-facing*2,y=obj.y+(btn(k_down) and 4 or 3)}
	foreach(obj.hair,function(h)
		h.x+=(last.x-h.x)/1.5
		h.y+=(last.y+0.5-h.y)/1.5
		circfill(h.x,h.y,h.size,8)
		last=h
	end)
end

unset_hair_color=function()
	pal(8,8)
end

player_spawn = {
	tile=1,
	init=function(this)
	 sfx(4)
		this.spr=3
		this.target= {x=this.x,y=this.y}
		this.y=128
		this.spd.y=-4
		this.state=0
		this.delay=0
		this.solids=false
		create_hair(this)
	end,
	update=function(this)
		-- jumping up
		if this.state==0 then
			if this.y < this.target.y+16 then
				this.state=1
				this.delay=3
			end
		-- falling
		elseif this.state==1 then
			this.spd.y+=0.5
			if this.spd.y>0 and this.delay>0 then
				this.spd.y=0
				this.delay-=1
			end
			if this.spd.y>0 and this.y > this.target.y then
				this.y=this.target.y
				this.spd = {x=0,y=0}
				this.state=2
				this.delay=5
				shake=5
				init_object(smoke,this.x,this.y+4)
				sfx(5)
			end
		-- landing
		elseif this.state==2 then
			this.delay-=1
			this.spr=6
			if this.delay<0 then
				destroy_object(this)
				init_object(player,this.x,this.y)
			end
		end
	end,
	draw=function(this)
		set_hair_color(max_djump)
		draw_hair(this,1)
		spr(this.spr,this.x,this.y,1,1,this.flip.x,this.flip.y)
		unset_hair_color()
	end
}
add(types,player_spawn)

spring = {
	tile=18,
	init=function(this)
		this.hide_in=0
		this.hide_for=0
	end,
	update=function(this)
		if this.hide_for>0 then
			this.hide_for-=1
			if this.hide_for<=0 then
				this.spr=18
				this.delay=0
			end
		elseif this.spr==18 then
			local hit = this.collide(player,0,0)
			if hit ~=nil and hit.spd.y>=0 then
				this.spr=19
				hit.y=this.y-4
				hit.spd.x*=0.2
				hit.spd.y=-3
				hit.djump=max_djump
				this.delay=10
				init_object(smoke,this.x,this.y)
				
				-- breakable below us
				local below=this.collide(fall_floor,0,1)
				if below~=nil then
					break_fall_floor(below)
				end
				
				psfx(8)
			end
		elseif this.delay>0 then
			this.delay-=1
			if this.delay<=0 then 
				this.spr=18 
			end
		end
		-- begin hiding
		if this.hide_in>0 then
			this.hide_in-=1
			if this.hide_in<=0 then
				this.hide_for=60
				this.spr=0
			end
		end
	end
}
add(types,spring)

function break_spring(obj)
	obj.hide_in=15
end

balloon = {
	tile=22,
	init=function(this) 
		this.offset=rnd(1)
		this.start=this.y
		this.timer=0
		this.hitbox={x=-1,y=-1,w=10,h=10}
	end,
	update=function(this) 
		if this.spr==22 then
			this.offset+=0.01
			this.y=this.start+sin(this.offset)*2
			local hit = this.collide(player,0,0)
			if hit~=nil and hit.djump<max_djump then
				psfx(6)
				init_object(smoke,this.x,this.y)
				hit.djump=max_djump
				this.spr=0
				this.timer=60
			end
		elseif this.timer>0 then
			this.timer-=1
		else 
		 psfx(7)
		 init_object(smoke,this.x,this.y)
			this.spr=22 
		end
	end,
	draw=function(this)
		if this.spr==22 then
			spr(13+(this.offset*8)%3,this.x,this.y+6)
			spr(this.spr,this.x,this.y)
		end
	end
}
add(types,balloon)

fall_floor = {
	tile=23,
	init=function(this)
		this.state=0
		this.solid=true
	end,
	update=function(this)
		-- idling
		if this.state == 0 then
			if this.check(player,0,-1) or this.check(player,-1,0) or this.check(player,1,0) then
				break_fall_floor(this)
			end
		-- shaking
		elseif this.state==1 then
			this.delay-=1
			if this.delay<=0 then
				this.state=2
				this.delay=60--how long it hides for
				this.collideable=false
			end
		-- invisible, waiting to reset
		elseif this.state==2 then
			this.delay-=1
			if this.delay<=0 and not this.check(player,0,0) then
				psfx(7)
				this.state=0
				this.collideable=true
				init_object(smoke,this.x,this.y)
			end
		end
	end,
	draw=function(this)
		if this.state!=2 then
			if this.state!=1 then
				spr(23,this.x,this.y)
			else
				spr(23+(15-this.delay)/5,this.x,this.y)
			end
		end
	end
}
add(types,fall_floor)

function break_fall_floor(obj)
 if obj.state==0 then
 	psfx(15)
		obj.state=1
		obj.delay=15--how long until it falls
		init_object(smoke,obj.x,obj.y)
		local hit=obj.collide(spring,0,-1)
		if hit~=nil then
			break_spring(hit)
		end
	end
end

smoke={
	init=function(this)
		this.spr=29
		this.spd.y=-0.1
		this.spd.x=0.3+rnd(0.2)
		this.x+=-1+rnd(2)
		this.y+=-1+rnd(2)
		this.flip.x=maybe()
		this.flip.y=maybe()
		this.solids=false
	end,
	update=function(this)
		this.spr+=0.2
		if this.spr>=32 then
			destroy_object(this)
		end
	end
}

fruit={
	tile=26,
	if_not_fruit=true,
	init=function(this) 
		this.start=this.y
		this.off=0
	end,
	update=function(this)
	 local hit=this.collide(player,0,0)
		if hit~=nil then
		 hit.djump=max_djump
			sfx_timer=20
			sfx(13)
			got_fruit[1+level_index()] = true
			init_object(lifeup,this.x,this.y)
			destroy_object(this)
		end
		this.off+=1
		this.y=this.start+sin(this.off/40)*2.5
	end
}
add(types,fruit)

fly_fruit={
	tile=28,
	if_not_fruit=true,
	init=function(this) 
		this.start=this.y
		this.fly=false
		this.step=0.5
		this.solids=false
		this.sfx_delay=8
	end,
	update=function(this)
		--fly away
		if this.fly then
		 if this.sfx_delay>0 then
		  this.sfx_delay-=1
		  if this.sfx_delay<=0 then
		   sfx_timer=20
		   sfx(14)
		  end
		 end
			this.spd.y=appr(this.spd.y,-3.5,0.25)
			if this.y<-16 then
				destroy_object(this)
			end
		-- wait
		else
			if has_dashed then
				this.fly=true
			end
			this.step+=0.05
			this.spd.y=sin(this.step)*0.5
		end
		-- collect
		local hit=this.collide(player,0,0)
		if hit~=nil then
		 hit.djump=max_djump
			sfx_timer=20
			sfx(13)
			got_fruit[1+level_index()] = true
			init_object(lifeup,this.x,this.y)
			destroy_object(this)
		end
	end,
	draw=function(this)
		local off=0
		if not this.fly then
			local dir=sin(this.step)
			if dir<0 then
				off=1+max(0,sign(this.y-this.start))
			end
		else
			off=(off+0.25)%3
		end
		spr(45+off,this.x-6,this.y-2,1,1,true,false)
		spr(this.spr,this.x,this.y)
		spr(45+off,this.x+6,this.y-2)
	end
}
add(types,fly_fruit)

lifeup = {
	init=function(this)
		this.spd.y=-0.25
		this.duration=30
		this.x-=2
		this.y-=4
		this.flash=0
		this.solids=false
	end,
	update=function(this)
		this.duration-=1
		if this.duration<= 0 then
			destroy_object(this)
		end
	end,
	draw=function(this)
		this.flash+=0.5

		print("1000",this.x-2,this.y,7+this.flash%2)
	end
}

fake_wall = {
	tile=64,
	if_not_fruit=true,
	update=function(this)
		this.hitbox={x=-1,y=-1,w=18,h=18}
		local hit = this.collide(player,0,0)
		if hit~=nil and hit.dash_effect_time>0 then
			hit.spd.x=-sign(hit.spd.x)*1.5
			hit.spd.y=-1.5
			hit.dash_time=-1
			sfx_timer=20
			sfx(16)
			destroy_object(this)
			init_object(smoke,this.x,this.y)
			init_object(smoke,this.x+8,this.y)
			init_object(smoke,this.x,this.y+8)
			init_object(smoke,this.x+8,this.y+8)
			init_object(fruit,this.x+4,this.y+4)
		end
		this.hitbox={x=0,y=0,w=16,h=16}
	end,
	draw=function(this)
		spr(64,this.x,this.y)
		spr(65,this.x+8,this.y)
		spr(80,this.x,this.y+8)
		spr(81,this.x+8,this.y+8)
	end
}
add(types,fake_wall)

key={
	tile=8,
	if_not_fruit=true,
	update=function(this)
		local was=flr(this.spr)
		this.spr=9+(sin(frames/30)+0.5)*1
		local is=flr(this.spr)
		if is==10 and is!=was then
			this.flip.x=not this.flip.x
		end
		if this.check(player,0,0) then
			sfx(23)
			sfx_timer=10
			destroy_object(this)
			has_key=true
		end
	end
}
add(types,key)

chest={
	tile=20,
	if_not_fruit=true,
	init=function(this)
		this.x-=4
		this.start=this.x
		this.timer=20
	end,
	update=function(this)
		if has_key then
			this.timer-=1
			this.x=this.start-1+rnd(3)
			if this.timer<=0 then
			 sfx_timer=20
			 sfx(16)
				init_object(fruit,this.x,this.y-4)
				destroy_object(this)
			end
		end
	end
}
add(types,chest)

platform={
	init=function(this)
		this.x-=4
		this.solids=false
		this.hitbox.w=16
		this.last=this.x
	end,
	update=function(this)
		this.spd.x=this.dir*0.65
		if this.x<-16 then this.x=128
		elseif this.x>128 then this.x=-16 end
		if not this.check(player,0,0) then
			local hit=this.collide(player,0,-1)
			if hit~=nil then
				hit.move_x(this.x-this.last,1)
			end
		end
		this.last=this.x
	end,
	draw=function(this)
		spr(11,this.x,this.y-1)
		spr(12,this.x+8,this.y-1)
	end
}

message={
	tile=86,
	last=0,
	draw=function(this)
		this.text="-- celeste mountain --#this memorial to those# perished on the climb"
		if this.check(player,4,0) then
			if this.index<#this.text then
			 this.index+=0.5
				if this.index>=this.last+1 then
				 this.last+=1
				 sfx(35)
				end
			end
			this.off={x=8,y=96}
			for i=1,this.index do
				if sub(this.text,i,i)~="#" then
					rectfill(this.off.x-2,this.off.y-2,this.off.x+7,this.off.y+6 ,7)
					print(sub(this.text,i,i),this.off.x,this.off.y,0)
					this.off.x+=5
				else
					this.off.x=8
					this.off.y+=7
				end
			end
		else
			this.index=0
			this.last=0
		end
	end
}
add(types,message)

big_chest={
	tile=96,
	init=function(this)
		this.state=0
		this.hitbox.w=16
	end,
	draw=function(this)
		if this.state==0 then
			local hit=this.collide(player,0,8)
			if hit~=nil and hit.is_solid(0,1) then
				music(-1,500,7)
				sfx(37)
				pause_player=true
				hit.spd.x=0
				hit.spd.y=0
				this.state=1
				init_object(smoke,this.x,this.y)
				init_object(smoke,this.x+8,this.y)
				this.timer=60
				this.particles={}
			end
			spr(96,this.x,this.y)
			spr(97,this.x+8,this.y)
		elseif this.state==1 then
			this.timer-=1
		 shake=5
		 flash_bg=true
			if this.timer<=45 and count(this.particles)<50 then
				add(this.particles,{
					x=1+rnd(14),
					y=0,
					h=32+rnd(32),
					spd=8+rnd(8)
				})
			end
			if this.timer<0 then
				this.state=2
				this.particles={}
				flash_bg=false
				new_bg=true
				init_object(orb,this.x+4,this.y+4)
				pause_player=false
			end
			foreach(this.particles,function(p)
				p.y+=p.spd
				line(this.x+p.x,this.y+8-p.y,this.x+p.x,min(this.y+8-p.y+p.h,this.y+8),7)
			end)
		end
		spr(112,this.x,this.y+8)
		spr(113,this.x+8,this.y+8)
	end
}
add(types,big_chest)

orb={
	init=function(this)
		this.spd.y=-4
		this.solids=false
		this.particles={}
	end,
	draw=function(this)
		this.spd.y=appr(this.spd.y,0,0.5)
		local hit=this.collide(player,0,0)
		if this.spd.y==0 and hit~=nil then
		 music_timer=45
			sfx(51)
			freeze=10
			shake=10
			destroy_object(this)
			max_djump=2
			hit.djump=2
		end
		
		spr(102,this.x,this.y)
		local off=frames/30
		for i=0,7 do
			circfill(this.x+4+cos(off+i/8)*8,this.y+4+sin(off+i/8)*8,1,7)
		end
	end
}

flag = {
	tile=118,
	init=function(this)
		this.x+=5
		this.score=0
		this.show=false
		for i=1,count(got_fruit) do
			if got_fruit[i] then
				this.score+=1
			end
		end
	end,
	draw=function(this)
		this.spr=118+(frames/5)%3
		spr(this.spr,this.x,this.y)
		if this.show then
			rectfill(32,2,96,31,0)
			spr(26,55,6)
			print("x"..this.score,64,9,7)
			draw_time(49,16)
			print("deaths:"..deaths,48,24,7)
		elseif this.check(player,0,0) then
			sfx(55)
	  sfx_timer=30
			this.show=true
		end
	end
}
add(types,flag)

room_title = {
	init=function(this)
		this.delay=5
 end,
	draw=function(this)
		this.delay-=1
		if this.delay<-30 then
			destroy_object(this)
		elseif this.delay<0 then
			
			rectfill(24,58,104,70,0)
			--rect(26,64-10,102,64+10,7)
			--print("---",31,64-2,13)
			if room.x==3 and room.y==1 then
				print("old site",48,62,7)
			elseif level_index()==30 then
				print("summit",52,62,7)
			else
				local level=(1+level_index())*100
				print(level.." m",52+(level<1000 and 2 or 0),62,7)
			end
			--print("---",86,64-2,13)
			
			draw_time(4,4)
		end
	end
}

-- object functions --
-----------------------

function init_object(type,x,y)
	if type.if_not_fruit~=nil and got_fruit[1+level_index()] then
		return
	end
	local obj = {}
	obj.type = type
	obj.collideable=true
	obj.solids=true

	obj.spr = type.tile
	obj.flip = {x=false,y=false}

	obj.x = x
	obj.y = y
	obj.hitbox = { x=0,y=0,w=8,h=8 }

	obj.spd = {x=0,y=0}
	obj.rem = {x=0,y=0}

	obj.is_solid=function(ox,oy)
		if oy>0 and not obj.check(platform,ox,0) and obj.check(platform,ox,oy) then
			return true
		end
		return solid_at(obj.x+obj.hitbox.x+ox,obj.y+obj.hitbox.y+oy,obj.hitbox.w,obj.hitbox.h)
		 or obj.check(fall_floor,ox,oy)
		 or obj.check(fake_wall,ox,oy)
	end
	
	obj.is_ice=function(ox,oy)
		return ice_at(obj.x+obj.hitbox.x+ox,obj.y+obj.hitbox.y+oy,obj.hitbox.w,obj.hitbox.h)
	end
	
	obj.collide=function(type,ox,oy)
		local other
		for i=1,count(objects) do
			other=objects[i]
			if other ~=nil and other.type == type and other != obj and other.collideable and
				other.x+other.hitbox.x+other.hitbox.w > obj.x+obj.hitbox.x+ox and 
				other.y+other.hitbox.y+other.hitbox.h > obj.y+obj.hitbox.y+oy and
				other.x+other.hitbox.x < obj.x+obj.hitbox.x+obj.hitbox.w+ox and 
				other.y+other.hitbox.y < obj.y+obj.hitbox.y+obj.hitbox.h+oy then
				return other
			end
		end
		return nil
	end
	
	obj.check=function(type,ox,oy)
		return obj.collide(type,ox,oy) ~=nil
	end
	
	obj.move=function(ox,oy)
		local amount
		-- [x] get move amount
 	obj.rem.x += ox
		amount = flr(obj.rem.x + 0.5)
		obj.rem.x -= amount
		obj.move_x(amount,0)
		
		-- [y] get move amount
		obj.rem.y += oy
		amount = flr(obj.rem.y + 0.5)
		obj.rem.y -= amount
		obj.move_y(amount)
	end
	
	obj.move_x=function(amount,start)
		if obj.solids then
			local step = sign(amount)
			for i=start,abs(amount) do
				if not obj.is_solid(step,0) then
					obj.x += step
				else
					obj.spd.x = 0
					obj.rem.x = 0
					break
				end
			end
		else
			obj.x += amount
		end
	end
	
	obj.move_y=function(amount)
		if obj.solids then
			local step = sign(amount)
			for i=0,abs(amount) do
	 		if not obj.is_solid(0,step) then
					obj.y += step
				else
					obj.spd.y = 0
					obj.rem.y = 0
					break
				end
			end
		else
			obj.y += amount
		end
	end

	add(objects,obj)
	if obj.type.init~=nil then
		obj.type.init(obj)
	end
	return obj
end

function destroy_object(obj)
	del(objects,obj)
end

function kill_player(obj)
	sfx_timer=12
	sfx(0)
	deaths+=1
	shake=10
	destroy_object(obj)
	dead_particles={}
	for dir=0,7 do
		local angle=(dir/8)
		add(dead_particles,{
			x=obj.x+4,
			y=obj.y+4,
			t=10,
			spd={
				x=sin(angle)*3,
				y=cos(angle)*3
			}
		})
		restart_room()
	end
end

-- room functions --
--------------------

function restart_room()
	will_restart=true
	delay_restart=15
end

function next_room()
 if room.x==2 and room.y==1 then
  music(30,500,7)
 elseif room.x==3 and room.y==1 then
  music(20,500,7)
 elseif room.x==4 and room.y==2 then
  music(30,500,7)
 elseif room.x==5 and room.y==3 then
  music(30,500,7)
 end

	if room.x==7 then
		load_room(0,room.y+1)
	else
		load_room(room.x+1,room.y)
	end
end

function load_room(x,y)
	has_dashed=false
	has_key=false

	--remove existing objects
	foreach(objects,destroy_object)

	--current room
	room.x = x
	room.y = y

	-- entities
	for tx=0,15 do
		for ty=0,15 do
			local tile = mget(room.x*16+tx,room.y*16+ty);
			if tile==11 then
				init_object(platform,tx*8,ty*8).dir=-1
			elseif tile==12 then
				init_object(platform,tx*8,ty*8).dir=1
			else
				foreach(types, 
				function(type) 
					if type.tile == tile then
						init_object(type,tx*8,ty*8) 
					end 
				end)
			end
		end
	end
	
	if not is_title() then
		init_object(room_title,0,0)
	end
end

-- update function --
-----------------------

function _update()
	frames=((frames+1)%30)
	if frames==0 and level_index()<30 then
		seconds=((seconds+1)%60)
		if seconds==0 then
			minutes+=1
		end
	end
	
	if music_timer>0 then
	 music_timer-=1
	 if music_timer<=0 then
	  music(10,0,7)
	 end
	end
	
	if sfx_timer>0 then
	 sfx_timer-=1
	end
	
	-- cancel if freeze
	if freeze>0 then freeze-=1 return end

	-- screenshake
	if shake>0 then
		shake-=1
		camera()
		if shake>0 then
			camera(-2+rnd(5),-2+rnd(5))
		end
	end
	
	-- restart (soon)
	if will_restart and delay_restart>0 then
		delay_restart-=1
		if delay_restart<=0 then
			will_restart=false
			load_room(room.x,room.y)
		end
	end

	-- update each object
	foreach(objects,function(obj)
		obj.move(obj.spd.x,obj.spd.y)
		if obj.type.update~=nil then
			obj.type.update(obj) 
		end
	end)
	
	-- start game
	if is_title() then
		if not start_game and (btn(k_jump) or btn(k_dash)) then
			music(-1)
			start_game_flash=50
			start_game=true
			sfx(38)
		end
		if start_game then
			start_game_flash-=1
			if start_game_flash<=-30 then
				begin_game()
			end
		end
	end
end

-- drawing functions --
-----------------------
function _draw()
	if freeze>0 then return end
	
	-- reset all palette values
	pal()
	
	-- start game flash
	if start_game then
		local c=10
		if start_game_flash>10 then
			if frames%10<5 then
				c=7
			end
		elseif start_game_flash>5 then
			c=2
		elseif start_game_flash>0 then
			c=1
		else 
			c=0
		end
		if c<10 then
			pal(6,c)
			pal(12,c)
			pal(13,c)
			pal(5,c)
			pal(1,c)
			pal(7,c)
		end
	end

	-- clear screen
	local bg_col = 0
	if flash_bg then
		bg_col = frames/5
	elseif new_bg~=nil then
		bg_col=2
	end
	rectfill(0,0,128,128,bg_col)

	-- clouds
	if not is_title() then
		foreach(clouds, function(c)
			c.x += c.spd
			rectfill(c.x,c.y,c.x+c.w,c.y+4+(1-c.w/64)*12,new_bg~=nil and 14 or 1)
			if c.x > 128 then
				c.x = -c.w
				c.y=rnd(128-8)
			end
		end)
	end

	-- draw bg terrain
	map(room.x * 16,room.y * 16,0,0,16,16,4)

	-- platforms/big chest
	foreach(objects, function(o)
		if o.type==platform or o.type==big_chest then
			draw_object(o)
		end
	end)

	-- draw terrain
	local off=is_title() and -4 or 0
	map(room.x*16,room.y * 16,off,0,16,16,2)
	
	-- draw objects
	foreach(objects, function(o)
		if o.type~=platform and o.type~=big_chest then
			draw_object(o)
		end
	end)
	
	-- draw fg terrain
	map(room.x * 16,room.y * 16,0,0,16,16,8)
	
	-- particles
	foreach(particles, function(p)
		p.x += p.spd
		p.y += sin(p.off)
		p.off+= min(0.05,p.spd/32)
		rectfill(p.x,p.y,p.x+p.s,p.y+p.s,p.c)
		if p.x>128+4 then 
			p.x=-4
			p.y=rnd(128)
		end
	end)
	
	-- dead particles
	foreach(dead_particles, function(p)
		p.x += p.spd.x
		p.y += p.spd.y
		p.t -=1
		if p.t <= 0 then del(dead_particles,p) end
		rectfill(p.x-p.t/5,p.y-p.t/5,p.x+p.t/5,p.y+p.t/5,14+p.t%2)
	end)
	
	-- draw outside of the screen for screenshake
	rectfill(-5,-5,-1,133,0)
	rectfill(-5,-5,133,-1,0)
	rectfill(-5,128,133,133,0)
	rectfill(128,-5,133,133,0)
	
	-- credits
	if is_title() then
		print("x+c",58,80,5)
		print("matt thorson",42,96,5)
		print("noel berry",46,102,5)
	end
	
	if level_index()==30 then
		local p
		for i=1,count(objects) do
			if objects[i].type==player then
				p = objects[i]
				break
			end
		end
		if p~=nil then
			local diff=min(24,40-abs(p.x+4-64))
			rectfill(0,0,diff,128,0)
			rectfill(128-diff,0,128,128,0)
		end
	end

end

function draw_object(obj)

	if obj.type.draw ~=nil then
		obj.type.draw(obj)
	elseif obj.spr > 0 then
		spr(obj.spr,obj.x,obj.y,1,1,obj.flip.x,obj.flip.y)
	end

end

function draw_time(x,y)

	local s=seconds
	local m=minutes%60
	local h=flr(minutes/60)
	
	rectfill(x,y,x+32,y+6,0)
	print((h<10 and "0"..h or h)..":"..(m<10 and "0"..m or m)..":"..(s<10 and "0"..s or s),x+1,y+1,7)

end

-- helper functions --
----------------------

function clamp(val,a,b)
	return max(a, min(b, val))
end

function appr(val,target,amount)
 return val > target 
 	and max(val - amount, target) 
 	or min(val + amount, target)
end

function sign(v)
	return v>0 and 1 or
								v<0 and -1 or 0
end

function maybe()
	return rnd(1)<0.5
end

function solid_at(x,y,w,h)
 return tile_flag_at(x,y,w,h,0)
end

function ice_at(x,y,w,h)
 return tile_flag_at(x,y,w,h,4)
end

function tile_flag_at(x,y,w,h,flag)
 for i=max(0,flr(x/8)),min(15,(x+w-1)/8) do
 	for j=max(0,flr(y/8)),min(15,(y+h-1)/8) do
 		if fget(tile_at(i,j),flag) then
 			return true
 		end
 	end
 end
	return false
end

function tile_at(x,y)
 return mget(room.x * 16 + x, room.y * 16 + y)
end

function spikes_at(x,y,w,h,xspd,yspd)
 for i=max(0,flr(x/8)),min(15,(x+w-1)/8) do
 	for j=max(0,flr(y/8)),min(15,(y+h-1)/8) do
 	 local tile=tile_at(i,j)
 	 if tile==17 and ((y+h-1)%8>=6 or y+h==j*8+8) and yspd>=0 then
 	  return true
 	 elseif tile==27 and y%8<=2 and yspd<=0 then
 	  return true
 		elseif tile==43 and x%8<=2 and xspd<=0 then
 		 return true
 		elseif tile==59 and ((x+w-1)%8>=6 or x+w==i*8+8) and xspd>=0 then
 		 return true
 		end
 	end
 end
	return false
end