-- title:  raster3
-- author: mieki256
-- desc:   short description
-- script: lua

t=0
x=64
y=32
sy=0

function TIC()
 local spd=2
 if btn(0) then y=y-spd end
 if btn(1) then y=y+spd end
 if btn(2) then x=x-spd end
 if btn(3) then x=x+spd end

 cls(0)
 map(0,0)
 local col=0
 local scale=2
 spr(1+t%60//30*2,x,y,col,scale,0,0,2,2)
 col=12
 print("HELLO WORLD!",84,28,col)
 t=t+1
 sy=math.floor((136*0.7)+16*math.sin(math.rad(t)))

 -- reset palette
 sync(1<<5)
end

--function SCN(row)
function BDR(row)
 local rx,ry=0,0
 
 if row==sy then
  -- palette change
  local PAL_ADDR=0x3FC0
  for i=PAL_ADDR,PAL_ADDR+16*3-1 do
   poke(i,peek(i)*0.5)
  end
 end
 
 if row<sy then
  rx=0
  ry=0
 else
  local dy=row-sy
  rx=1.5*math.cos(math.rad(4*t+55*dy))
  -- ry=-dy*2 -- TIC-80 0.70.6
  ry=dy*2 -- TIC-80 1.0.2164
 end
 
 local SCROFSX=0x3FF9
 local SCROFSY=0x3FFA
 poke(SCROFSX,rx)
 poke(SCROFSY,ry)
end