Skip to content

Instantly share code, notes, and snippets.

@pkoch

pkoch/game.lua

Created Nov 3, 2020
Embed
What would you like to do?
-- From https://nerdyteachers.com/Explain/Platformer/#full_code
--variables
function _init()
player={
sp=1,
x=59,
y=59,
w=8,
h=8,
flp=false,
dx=0,
dy=0,
max_dx=2,
max_dy=3,
acc=0.5,
boost=4,
anim=0,
running=false,
jumping=false,
falling=false,
sliding=false,
landed=false
}
gravity=0.3
friction=0.85
--simple camera
cam_x=0
--map limits
map_start=0
map_end=1024
end
-->8
--update and draw
function _update()
player_update()
player_animate()
--simple camera
cam_x=player.x-64+(player.w/2)
if cam_x<map_start then
cam_x=map_start
end
if cam_x>map_end-128 then
cam_x=map_end-128
end
camera(cam_x,0)
end
function _draw()
cls()
map(0,0)
spr(player.sp,player.x,player.y,1,1,player.flp)
end
-->8
--collisions
function collide_map(obj,aim,flag)
--obj = table needs x,y,w,h
--aim = left,right,up,down
local x=obj.x local y=obj.y
local w=obj.w local h=obj.h
local x1=0 local y1=0
local x2=0 local y2=0
if aim=="left" then
x1=x-1 y1=y
x2=x y2=y+h-1
elseif aim=="right" then
x1=x+w-1 y1=y
x2=x+w y2=y+h-1
elseif aim=="up" then
x1=x+2 y1=y-1
x2=x+w-3 y2=y
elseif aim=="down" then
x1=x+2 y1=y+h
x2=x+w-3 y2=y+h
end
--pixels to tiles
x1/=8 y1/=8
x2/=8 y2/=8
if fget(mget(x1,y1), flag)
or fget(mget(x1,y2), flag)
or fget(mget(x2,y1), flag)
or fget(mget(x2,y2), flag) then
return true
else
return false
end
end
-->8
--player
function player_update()
--physics
player.dy+=gravity
player.dx*=friction
--controls
if btn(⬅️) then
player.dx-=player.acc
player.running=true
player.flp=true
end
if btn(➡️) then
player.dx+=player.acc
player.running=true
player.flp=false
end
--slide
if player.running
and not btn(⬅️)
and not btn(➡️)
and not player.falling
and not player.jumping then
player.running=false
player.sliding=true
end
--jump
if btnp(❎)
and player.landed then
player.dy-=player.boost
player.landed=false
end
--check collision up and down
if player.dy>0 then
player.falling=true
player.landed=false
player.jumping=false
player.dy=limit_speed(player.dy,player.max_dy)
if collide_map(player,"down",0) then
player.landed=true
player.falling=false
player.dy=0
player.y-=((player.y+player.h+1)%8)-1
end
elseif player.dy<0 then
player.jumping=true
if collide_map(player,"up",1) then
player.dy=0
end
end
--check collision left and right
if player.dx<0 then
player.dx=limit_speed(player.dx,player.max_dx)
if collide_map(player,"left",1) then
player.dx=0
end
elseif player.dx>0 then
player.dx=limit_speed(player.dx,player.max_dx)
if collide_map(player,"right",1) then
player.dx=0
end
end
--stop sliding
if player.sliding then
if abs(player.dx)<.2
or player.running then
player.dx=0
player.sliding=false
end
end
player.x+=player.dx
player.y+=player.dy
--limit player to map
if player.x<map_start then
player.x=map_start
end
if player.x>map_end-player.w then
player.x=map_end-player.w
end
end
function player_animate()
if player.jumping then
player.sp=7
elseif player.falling then
player.sp=8
elseif player.sliding then
player.sp=9
elseif player.running then
if time()-player.anim>.1 then
player.anim=time()
player.sp+=1
if player.sp>6 then
player.sp=3
end
end
else --player idle
if time()-player.anim>.3 then
player.anim=time()
player.sp+=1
if player.sp>2 then
player.sp=1
end
end
end
end
function limit_speed(num,maximum)
return mid(-maximum,num,maximum)
end
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment