SpaceImpact

Flow description

# @name Space Impact
# @desc Tiny self-playing retro shooter animation
# @version 0.4
# @author mckdoubleu

class SpaceImpact
  var w
  var h
  var py
  var ex
  var ey
  var bullet
  var by
  var boom
  var boomx
  var boomy
  var frame
  var wait
  var wave
  var last

  def init()
    self.w=width()
    self.h=height()
    self.py=self.h/2
    self.ex=self.w-2
    self.ey=2
    self.bullet=-1
    self.by=0
    self.boom=0
    self.boomx=0
    self.boomy=0
    self.frame=0
    self.wait=0
    self.wave=0
    self.last=now_ms()
  end

  def spawn()
    self.wave+=1
    self.ex=self.w-2
    self.ey=1+((self.wave*3)%(self.h-2))
  end

  def update()
    var t=now_ms()
    if t-self.last<90
      return
    end
    self.last=t
    self.frame+=1

    if self.boom>0
      self.boom-=1
    end

    if self.bullet>=0
      self.bullet+=2
      if self.bullet>=self.w
        self.bullet=-1
      end
    end

    if self.ex>=0
      if self.frame%2==0
        self.ex-=1
      end

      if self.frame%2==0
        if self.ey<self.py && self.py>1
          self.py-=1
        elif self.ey>self.py && self.py<self.h-2
          self.py+=1
        end
      end

      if self.bullet<0 && self.frame%5==0
        self.bullet=7
        self.by=self.py
      end

      if self.bullet>=self.ex-1 && self.bullet<=self.ex+1
        if self.by==self.ey
          self.bullet=-1
          self.boom=3
          self.boomx=self.ex
          self.boomy=self.ey
          self.ex=-1
          self.wait=5
        end
      end

      if self.ex<1
        self.ex=-1
        self.wait=5
      end
    else
      if self.wait>0
        self.wait-=1
      else
        self.spawn()
      end
    end
  end

  def draw_stars()
    var shift=self.frame%self.w
    for i : 0 .. 7
      var x=(i*5+self.w-shift)%self.w
      var y=(i*3+1)%self.h
      var c=0x26364D
      if i%3==0
        c=0xA8CFFF
      end
      pixel(x,y,c)
    end
  end

  def draw_enemy()
    if self.ex<1
      return
    end
    var x=self.ex
    var y=self.ey
    pixel(x,y,0xFF416C)
    if x>0
      pixel(x-1,y,0xB51F43)
    end
    if x+1<self.w
      pixel(x+1,y,0xFF416C)
    end
    pixel(x,y-1,0xFF94AA)
    pixel(x,y+1,0xFF94AA)
  end

  def draw_ship()
    var y=self.py
    pixel(2,y,0x44DFFF)
    pixel(3,y,0x44DFFF)
    pixel(4,y,0x44DFFF)
    pixel(5,y,0xC8FAFF)
    pixel(3,y-1,0x44DFFF)
    pixel(3,y+1,0x44DFFF)

    if self.frame%2==0
      pixel(1,y,0xFFB12B)
    else
      pixel(1,y,0xFF5722)
    end
  end

  def draw_bullet()
    if self.bullet>=0 && self.bullet<self.w
      pixel(self.bullet,self.by,0xFFF36B)
      if self.bullet>0
        pixel(self.bullet-1,self.by,0xFF9F2F)
      end
    end
  end

  def draw_boom()
    if self.boom<=0
      return
    end
    var x=self.boomx
    var y=self.boomy
    pixel(x,y,0xFFFFFF)

    if x>0
      pixel(x-1,y,0xFFD23F)
    end
    if x+1<self.w
      pixel(x+1,y,0xFFD23F)
    end
    if y>0
      pixel(x,y-1,0xFF6A20)
    end
    if y+1<self.h
      pixel(x,y+1,0xFF6A20)
    end
  end

  def draw()
    self.update()
    clear(0)
    self.draw_stars()
    self.draw_enemy()
    self.draw_bullet()
    self.draw_boom()
    self.draw_ship()
  end

  def duration()
    return 30000
  end
end

return SpaceImpact()