This is my PICO-1k jam entry. The entire source code is 1024 characters in PICO-8, including the comment at the top. Arrows to fly, button (z on keyboard) to fire.

--top*burn a=48n=32k=64_={}camera(-k,-k)c=16x=0y=0t=0o=0g=0q,b,r,s,h=sqrt,btn,rnd,spr,sspr::a::l=t%8/4map(0,0,-k,-k,c,c)for j=3,k do z=j/4h(q(q(z))*c-l,1,k+k,1,-j*n,j,k*4*z,1)end l=l<1o=max(o-1,0)f=b(4)and o<n if f then m(r(3))o+=2 if(o>n)o=98 end i=l and o>n and s(124,-k,-40,4,1)or h(0,56,min(o,n),6,-k,-a),l and t>650or h(a,n,n-t/n,8,n,-a) i=b(1)p=24m=sfx if(i and x<c)x+=2 p=c if(b(0)and-k<x)x-=2 p=c if(b(2)and y<n)y+=1 p=k if(b(3)and-n<y)y-=1 p=74 s(86,x+8,a,4,2) for e in all(_)do e.x+=e.d e.z+=.1 j=e.d<0w=88z=4/e.z if(e.l==0or e.z>k)del(_,e) if(e.l)e.l-=1 j=r(2)>1goto e h(56,k,c,c,e.x*z+24*z,a*z,c*z,c*z,j)w=k if(f and max(abs(u/z-e.x-21),abs(v/z-e.y-8))<8)e.l=8m(3)g+=.75 ::e::h(0,w,56,24,e.x*z,e.y*z,56*z,24*z,j)end if(r(98)<1)d=sgn(r(2)-1)add(_,{x=r(n)-d*k-c,d=d,y=r(k)-a,z=1}) z=.7u=x*z+13v=y*z-8s(2,u,v) if(f and l)s(c,u*.9,v*z)s(17,u,y*z-5)z+=.1 s(38,x*z+10,y*z-2,2,1)z+=.1 s(46,x*z+14,y*z+1,2,1) s(p,x,y,6,3,i)s(240,-30,-41,g,1)flip()t+=1 if(t<999)goto a ::g::s(137+t%2*k,t%192-140,-n,7,1)flip()t+=1 goto g |

This entire cart is 243 characters (plus six sprites). The code is just:

k,f,q,b=64,0,sqrt,btn x,y=k,k::a::cls(12)for j=3,k do s=j/4 sspr(q(q(s))*16-f%8/4,1,k+k,1,k-j*32,k+j,k*4*s,1)end r=b(1)p=22 if(r)x+=2,p=16 if(b(0))x-=2,p=16 if(b(2))y+=1,p=k if(b(3))y-=1,p=70 spr(28,x+8,99,4,2)spr(p,x,y,6,3,r)flip()f+=1 goto a |

It was a successful attempt to code the basics of a game in two tweets. There's actually enough room to clamp x and y to the screen. I hope someone will use this as a starter to make a real game.

The bottom part is the waterfall demo and some generic particle emitter code.

You can save a few more cycles if you hardcode the gravity constant. Otherwise I believe that this is close to optimal.

More information at my github

I wrote Brick Breaker as a full-featured, polished PICO-8 sample program. It was an opportunity for me to learn the PICO-8 Lua variant and now stands as a good example program for other programmers new to PICO-8.

It demonstrates (commented) use of:

- loops
- create & destroy objects
- local vars
- text
- multiple levels
- sprite animation
- powerups
- particles
- map usage
- title screen & game over
- sound effects
- music
- sprite packing
- basic physics
- assertions

as well as some techniques for reducing token count, a limited resource on PICO-8.

I did most of this work in parallel with the 2017 Global Game Jam. The PICO-8 version of Brick Breaker is based on my JavaScript Brick Breaker sample program, which you can play here.

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