Pico-8 Hero - Breakout - End of Ep. 17

--goals
-- 4. levels

--    level finished detection
--    next level screen

-- 5. diffrent bricks
-- 6. (powerups)
-- 7. juicyness
--     arrow anim
--     text blinking
--     particles
--     screenshake
-- 8. high score

function _init()
 cls()
 mode="start"
 level=""
 debug=""
 levelnum = 1
 levels={}
 levels[1] = "x5b"
 levels[2] = "x4b"
 --levels[2] = "bxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxbxb"
end

function _update60()
 if mode=="game" then
  update_game()
 elseif mode=="start" then
  update_start()
 elseif mode=="gameover" then
  update_gameover()
 elseif mode=="levelover" then
  update_levelover()
 end
end

function update_start()
 if btnp(4) then
  startgame()
 end
end

function startgame()
 mode="game"
 ball_r=2
 ball_dr=0.5

 pad_x=52
 pad_y=120
 pad_dx=0
 pad_w=24
 pad_h=3
 pad_c=7

 brick_w=9
 brick_h=4

 levelnum = 1
 level = levels[levelnum]
 buildbricks(level)
 --brick_y=20

 lives=3
 points=0

 sticky=true

 chain=1 --combo chain multiplier

 serveball()
end

function nextlevel()
 mode="game"
 pad_x=52
 pad_y=120
 pad_dx=0

 levelnum+=1
 if levelnum > #levels then
  -- we've beaten the gane
  -- we need some kind of special
  -- screen here
  mode="start"
  return
 end
 level=levels[levelnum]
 buildbricks(level)

 sticky=true
 chain=1

 serveball()
end

function buildbricks(lvl)
 local i,j,o,chr,last
 brick_x={}
 brick_y={}
 brick_v={}

 j=0
 for i=1,#lvl do
  j+=1
  chr=sub(lvl,i,i)
  if chr=="b" then
   last="b"
   add(brick_x,4+((j-1)%11)*(brick_w+2))
   add(brick_y,20+flr((j-1)/11)*(brick_h+2))
   add(brick_v,true)
  elseif chr=="x" then
   last="x"
  elseif chr=="/" then
   j=(flr((j-1)/11)+1)*11
  elseif chr>="1" and chr<="9" then
   for o=1,chr+0 do
    if last=="b" then
     add(brick_x,4+((j-1)%11)*(brick_w+2))
     add(brick_y,20+flr((j-1)/11)*(brick_h+2))
     add(brick_v,true)
    elseif last=="x" then
     --nothing
    end
    j+=1
   end
   j-=1
  end
 end
end

function levelfinished()
 if #brick_v == 0 then return true end

 for i=1,#brick_v do
  if brick_v[i] == true then
   return false
  end
 end
 return true
end

function serveball()
 ball_x=pad_x+flr(pad_w/2)
 ball_y=pad_y-ball_r
 ball_dx=1
 ball_dy=-1
 ball_ang=1
 chain=1

 sticky=true
 --0.50
 --1.30
end

function setang(ang)
 ball_ang=ang
 if ang==2 then
  ball_dx=0.50*sign(ball_dx)
  ball_dy=1.30*sign(ball_dy)
 elseif ang==0 then
  ball_dx=1.30*sign(ball_dx)
  ball_dy=0.50*sign(ball_dy)
 else
  ball_dx=1*sign(ball_dx)
  ball_dy=1*sign(ball_dy)
 end
end

function sign(n)
 if n<0 then
  return -1
 elseif n>0 then
  return 1
 else
  return 0
 end
end

function gameover()
 mode="gameover"
end

function levelover()
 mode="levelover"
end

function update_gameover()
 if btnp(4) then
  startgame()
 end
end

function update_levelover()
 if btnp(4) then
  nextlevel()
 end
end

function update_game()
 local buttpress=false
 local nextx,nexty,brickhit

 if btn(0) then
  --left
  pad_dx=-2.5
  buttpress=true
  --pad_x-=5
  if sticky then
   ball_dx=-1
  end
 end
 if btn(1) then
  --right
  pad_dx=2.5
  buttpress=true
  --pad_x+=5
  if sticky then
   ball_dx=1
  end
 end
 if sticky and btn(4) then
  sticky=false
 end

 if not(buttpress) then
  pad_dx=pad_dx/1.3
 end
 pad_x+=pad_dx
 pad_x=mid(0,pad_x,127-pad_w)

 if sticky then
  ball_x=pad_x+flr(pad_w/2)
  ball_y=pad_y-ball_r-1
 else
  --regular ball physics
  nextx=ball_x+ball_dx
  nexty=ball_y+ball_dy

  if nextx > 124 or nextx < 3 then
   nextx=mid(0,nextx,127)
   ball_dx = -ball_dx
   sfx(0)
  end
  if nexty < 10 then
   nexty=mid(0,nexty,127)
   ball_dy = -ball_dy
   sfx(0)
  end

  -- check if ball hit pad
  if ball_box(nextx,nexty,pad_x,pad_y,pad_w,pad_h) then
   -- deal with collision
   if deflx_ball_box(ball_x,ball_y,ball_dx,ball_dy,pad_x,pad_y,pad_w,pad_h) then
    --ball hit paddle on the side
    ball_dx = -ball_dx
    if ball_x < pad_x+pad_w/2 then
     nextx=pad_x-ball_r
    else
     nextx=pad_x+pad_w+ball_r
    end
   else
    --ball hit paddle on the top/bottom
    ball_dy = -ball_dy
    if ball_y > pad_y then
     --bottom
     nexty=pad_y+pad_h+ball_r
    else
     --top
     nexty=pad_y-ball_r
     if abs(pad_dx)>2 then
      --change angle
      if sign(pad_dx)==sign(ball_dx) then
       --flatten angle
       setang(mid(0,ball_ang-1,2))
      else
       --raise angle
       if ball_ang==2 then
        ball_dx=-ball_dx
       else
        setang(mid(0,ball_ang+1,2))
       end
      end
     end
    end
   end
   sfx(1)
   chain=1
  end

  brickhit=false
  for i=1,#brick_x do
   -- check if ball hit brick
   if brick_v[i] and ball_box(nextx,nexty,brick_x[i],brick_y[i],brick_w,brick_h) then
    -- deal with collision
    if not(brickhit) then
     if deflx_ball_box(ball_x,ball_y,ball_dx,ball_dy,brick_x[i],brick_y[i],brick_w,brick_h) then
      ball_dx = -ball_dx
     else
      ball_dy = -ball_dy
     end
    end
    brickhit=true
    sfx(2+chain)
    brick_v[i]=false
    points+=10*chain
    chain+=1
    chain=mid(1,chain,7)
    if levelfinished() then
     _draw()
     levelover()
    end
   end
  end
  ball_x=nextx
  ball_y=nexty

  if nexty > 127 then
   sfx(2)
   lives-=1
   if lives<0 then
    gameover()
   else
    serveball()
   end
  end
 end
end


function _draw()
 if mode=="game" then
  draw_game()
 elseif mode=="start" then
  draw_start()
 elseif mode=="gameover" then
  draw_gameover()
 elseif mode=="levelover" then
  draw_levelover()
 end
end

function draw_start()
 cls()
 print("pico hero breakout",30,40,7)
 print("press \151 to start",32,80,11)
end

function draw_gameover()
 rectfill(0,60,128,75,0)
 print("game over",46,62,7)
 print("press \151 to restart",27,68,6)
end

function draw_levelover()
 rectfill(0,60,128,75,0)
 print("stage clear!",46,62,7)
 print("press \151 to continue",27,68,6)
end

function draw_game()
 local i

 cls(1)
 circfill(ball_x,ball_y,ball_r, 10)
 if sticky then
  -- serve preview
  line(ball_x+ball_dx*4,ball_y+ball_dy*4,ball_x+ball_dx*6,ball_y+ball_dy*6,10)
 end

 rectfill(pad_x,pad_y,pad_x+pad_w,pad_y+pad_h,pad_c)

 --draw bricks
 for i=1,#brick_x do
  if brick_v[i] then
   rectfill(brick_x[i],brick_y[i],brick_x[i]+brick_w,brick_y[i]+brick_h,14)
  end
 end

 rectfill(0,0,128,6,0)
 if debug!="" then
  print(debug,1,1,7)
 else
  print("lives:"..lives,1,1,7)
  print("score:"..points,40,1,7)
  print("chain:"..chain.."x",100,1,7)
 end
end

function ball_box(bx,by,box_x,box_y,box_w,box_h)
 -- checks for a collion of the ball with a rectangle
 if by-ball_r > box_y+box_h then return false end
 if by+ball_r < box_y then return false end
 if bx-ball_r > box_x+box_w then return false end
 if bx+ball_r < box_x then return false end
 return true
end

function deflx_ball_box(bx,by,bdx,bdy,tx,ty,tw,th)
    local slp = bdy / bdx
    local cx, cy
    if bdx == 0 then
        return false
    elseif bdy == 0 then
        return true
    elseif slp > 0 and bdx > 0 then
        cx = tx - bx
        cy = ty - by
        return cx > 0 and cy/cx < slp
    elseif slp < 0 and bdx > 0 then
        cx = tx - bx
        cy = ty + th - by
        return cx > 0 and cy/cx >= slp
    elseif slp > 0 and bdx < 0 then
        cx = tx + tw - bx
        cy = ty + th - by
        return cx < 0 and cy/cx <= slp
    else
        cx = tx + tw - bx
        cy = ty - by
        return cx < 0 and cy/cx >= slp
    end
end