Clean up dead sprites properly.

src/bullet.lua

@@ -38,7 +38,11 @@ function Bullet:update()
       obj:damage(self.damage)
    end
 
-   if #collisions >= 1 then
+   if #collisions >= 1 or self:outOfBounds() then
       self:remove()
    end
 end
+
+function Bullet:outOfBounds()
+   return self.x < 0 or self.y < 0 or self.x > 400 or self.y > 240
+end

src/enemy/ebi.lua

@@ -17,9 +17,17 @@ function Ebi:init()
    if math.random(2) == 1 then
       dir = -1
    end
+
    self.vector = {x=0, y=dir}
 
-   self:weaponTimer()
+   self.weaponTimer = playdate.timer.new(2500,
+      function()
+         local b = Bullet(2, 1, {x=-1, y=0}, 0x2)
+         b:moveTo(self.x - (self.width/2) - 1, self.y)
+         b:add()
+      end
+   )
+   self.weaponTimer.repeats = true
 end
 
 function Ebi:update()
@@ -31,13 +39,7 @@ function Ebi:update()
    end
 end
 
-function Ebi:weaponTimer()
+function Ebi:delete()
-   local t = playdate.timer.new(1000,
+   Ebi.super.delete(self)
-      function()
+   self.weaponTimer:remove()
-         local b = Bullet(2, 1, {x=-1, y=0}, 0x2)
-         b:moveTo(self.x - (self.width/2) - 1, self.y)
-         b:add()
-      end
-   )
-   t.repeats = true
 end

src/entity.lua

@@ -30,7 +30,7 @@ function Entity:damage(amount)
    self.health = math.max(self.health - (amount - self.armor), 0)
 
    if self.health == 0 then
-      self:remove()
+      self:delete()
    end
 end
 
@@ -38,3 +38,8 @@ function Entity:update()
    local collisions = select(3, self:moveWithCollisions(self.x + self.vector.x, self.y + self.vector.y))
    return collisions
 end
+
+-- override this if you create timers
+function Entity:delete()
+   self:remove()
+end

src/main.lua

@@ -46,8 +46,14 @@ function setup()
    enemy:add()
 
    makeWalls()
-   
    drawBackground()
+
+   -- debug, TODO remove this code
+   playdate.inputHandlers.push({
+         BButtonUp = function()
+            print(gfx.sprite.spriteCount())
+         end
+   })
 end
 
 function makeWalls()