Memory City

press and hold the circle button to dissolve the city

Tweetcart Sourcecode (266 Characters):

poke(▒|▤,웃/●)memset(81-😐,170,8)s=●-웃 pal({0,0,-15,1,-4,12,13,12,-4,1,-15,1,-4,1,-15},1)pal({-15,1,-4,1,-15,1,-4,12,13,12,-4,1,-15,0,0},2)cls()r=rnd::_:: x=r(128)y=r(16)+56pset(x,y,r(16))d=r(8191)poke(s+d-tonum(btn(4))0.5,@(s+d-64(mid(1,(r()-.5)/0)*2-1)))
goto _

Explanation:

-- instruct the pico8 to use the second palette, for the top half of the screen only poke(▒|▤,웃/●) memset(81-😐,170,8)

-- save space by encoding the memory address for the display s=●-웃

-- set both palette one and two pal({0,0,-15,1,-4,12,13,12,-4,1,-15,1,-4,1,-15},1) pal({-15,1,-4,1,-15,1,-4,12,13,12,-4,1,-15,0,0},2)

-- clear the screen cls()

-- save characters when calling rnd r=rnd

-- mark the start of the draw loop ::_::

-- random position for x x=r(128) -- random position for y within narrow band y=r(16)+56 -- draw pixel of random color at that position pset(x,y,r(16))

-- choose a position in the display memory d=r(8191)

-- the part that makes the "city" poke( s+d-tonum(btn(4))0.5, -- write to this position, if the button is pressed shift by -0.5 @(s+d-64(mid(1,(r()-.5)/0)*2-1)) -- peek @ this position, last part is to get 1 or -1 )
goto _