diff --git a/docs/camera-shaking.md b/docs/camera-shaking.md
deleted file mode 100644
index 92dadd9..0000000
--- a/docs/camera-shaking.md
+++ /dev/null
@@ -1,43 +0,0 @@
-backup camera shaking.
-
-```lua
-function Camera:start(options)
-  _G.log('🔴 Camera is DEPRECATED! use App.game.camera instead.')
-  self.options = _.extend(self.options, options)
-  transition.cancel(self.display)
-  self.display.alpha = 1
-  App.hud:toFront()
-
-  self.moveDisplay = function()
-    if (self.shakeCount % shakePeriod == 0) then
-      self.display.x = self.display.x0 + math.random(-xShake, xShake)
-      self.display.y = self.display.y0 + math.random(-yShake, yShake)
-    end
-    self.shakeCount = self.shakeCount + 1
-  end
-
-  self.startShake = function()
-    self.display.x0 = self.display.x
-    self.display.y0 = self.display.y
-    self.shakeCount = 0
-    Runtime:addEventListener('enterFrame', self.moveDisplay)
-  end
-
-  self.stopShake = function()
-    Runtime:removeEventListener('enterFrame', self.moveDisplay)
-    self.display.x = INIT_X
-    self.display.y = INIT_Y
-    self.shaking = false
-  end
-end
-
-function Camera:shake()
-  if (self.shaking) then
-    timer.cancel(self.shaking)
-    self.stopShake()
-  end
-
-  self.startShake()
-  self.shaking = timer.performWithDelay(250, self.stopShake)
-end
-```