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function _init() 
   -- allow mouse :)
   poke(0x5f2d, 1)

   cur_init()
   ants_init()
   food_init()
end

function _update60()
   cur_update()
   local click=stat(34)
   --left click
   if(1==click) then
      sfx(0,-1,4)
      ants_add(cur_x,cur_y)
   end
   --right click
   if(2==click) then
      food_add(cur_x,cur_y)
   end
   
   food_update()
   ants_update()
end

function _draw()
   cls(4)
   food_draw()
   ants_draw()
   --ants_count()
   cur_draw()
end

function cur_init()
   cur_spr=1
   cur_x=60
   cur_y=60
end

function cur_draw()
   spr(cur_spr,cur_x,cur_y)
end

function cur_update()
   --mouse loc
   cur_x=stat(32)-1
   cur_y=stat(33)-1
end

function ants_init()
   ants={}
end

function ants_add(x,y)
   ants[#ants+1]={x=x,y=y,age=0}
end

function ants_loop(func)
   loop_pixels(ants,func)
end

function ants_draw()
   ants_loop(
      function(ant)
         pset(ant.x,ant.y,0)
      end
   )
end

function ants_move()
   ants_loop(ant_move)
end

function ant_move(ant)
   local movement=rnd(100)
   
   if(95<movement) then
      ant.x=ant.x+1
   elseif(90<movement) then
      ant.y=ant.y+1
   elseif(85<movement) then
      ant.x=ant.x-1
   elseif(80<movement) then
      ant.y=ant.y-1
   end
   
   ant.x=loop_screen(ant.x)
   ant.y=loop_screen(ant.y)
end

function ants_age()
   ants_loop(function(ant)
         -- basic rand change to die
         if(ant) then
			local dead=
               flr(rnd(2000-ant.age))
			if(0==dead) then
               del(ants,ant)
			else
               ant.age = ant.age+1
			end
         end
   end)
end

function ants_count()
   local text="ants: " .. #ants
   print(text,2,120,6)
end

function ants_eat()
   -- we actually loop the food
   -- to easy unset it
   food_loop(function(food)
         if(food) then
			local eat=pget(food.x,food.y)
			if(eat==0) -- has ant on it
			then
               --make ant live longer
               foreach(ants, function(ant)
                          if(ant.x==food.x and 
                             ant.y==food.y) then
                             ant.age=ant.age-100
                          end
               end)
               --remove the food
               del(foods,food)
               sfx(1)
			end
         end
   end)
end

function ants_update()
   ants_move()
   ants_eat()
   ants_age()
end

function loop_screen(pos)
   if(128<pos) return 0
   if(0>pos) return 128

   return pos
   end

function loop_pixels(arr,func)
   for i=1,#arr do
      func(arr[i])
   end
end

function food_init()
   f_sprite={2,3}
   foods={}
   food_can_add=0
end

function food_add(c_x,c_y)
   --only add if not delayed
   if(0<=food_can_add) return
   
   sfx(2)
   --reset delay
   food_can_add=25
   local s_offset=
      rnd(f_sprite) * 8
   
   -- loop the sprite to add
   -- pixels
   for x=0,7 do
      for y=0,7 do
         local pix=sget(x+s_offset,y)
         if(0!=pix) then
            foods[#foods+1]=
               {x=c_x+x,y=c_y+y,col=pix}
         end
      end
   end
end

function food_draw()
   food_loop(
      function(food)
         pset(food.x,food.y,food.col)
      end
   )
end

function food_loop(func)
   loop_pixels(foods,func)
end

function food_update()
   food_can_add=food_can_add-1
end

this one's mostly straightforward: call the init, update, and draw functions of further tabs. in init, we poke to enable mouse use, in update we handle clicks, and in draw we clear the screen.

another simple one. in `init`, we set our cursor sprite, in `update` we pull in the x and y position of our cursor with inexplicable functions even _i_ dont understand (minus 1, for some sweet visual alignment tricks: it makes sure we dont hide our single pixel ants), and draw draws a sprite to the screen at that position. i think its neat. its simple. its a software sort of thing

now we're doing something! we've got a lot here. if you've noticed, i have a tendency to order functions in a sort of least-to-most order, aka 'reverse', so let's describe them in reverse also, starting at the bottom of our code:

ants_update

the simple one: we call all the functions we write above. our ants will move, eat, then age and possibly die

ants_eat

our first hard one, in part reliable on some functions in our food tab (so read ahead!). in short, we have an array of pixels of ‘food’ as well as their x and y positions. we then read the screen data of the foods x and y coords: if its palette is 0, which is an ant, we 1) make the ant live longer by subtracting from its age value and 2) delete the food from the food array (see that tab bb). we also play a sound effect

ants_count

debug func: prints the count of ants to the screen

ants_age

we loop through our ants via the to-be-described ants_loop function and try to kill them via rng. essentially: the closer their age gets to 2000, the higher the chance they die. if they live, we age them by one, increasing their chance to die later

ants_move and ant_move

loop through and move our ants. this parts lame as hell right now, just randomizing the direction and checking to loop the screen. this’ll be a HUGE change point in our shared future

ants_draw

loop our ants and set their pixels on the screen. simple as hell

ants_loop

and you thought you might learn? no! we call a loop pixels functions on our ant, described elsewhere!

ants_add and ants_init

simple: we add an ant object at x and y in ants_add, we create a global ants array in init. this is real simple stuff, unfortunately

aint the most complicated things so simple also? `loop_screen` makes sure our position is on the 128x128 screen, `loop_pixels` takes in an array and runs a function on every member of it

why is these together, if so different? i dont’ know. i wrote this months ago

our last little bit of complexity, then we're through. You've got this, reader. I've got this, writer, too.

in init, we set up three variables. f_sprite holds a list of sprites that we can produce as food, foods holds all the food pixels we’ve set on screen (the same way we’ve set pixels for ants), and food_can_add helps us set a little delay so that we can’t just paint food across our screen

food_add adds food to the x+y off the cursor: first we made sure our food can be added by checking if our food_can_add is zero (or less---so we don’t have to worry about keeping the addable time to zero); if we’re good, we play a little sound, reset our food delay to 25 frames, then pick a sprite at random from our f_sprite variable set above. with that in place, we loop through the pixels of our food sprite and add them to our food array at the cursor location

food_draw loops these pixels to add them to the screen; food_loop makes looping these pixels easier

finally, on food_update, we count our food adding counter down one tick per frame