added missing files

slider.lua

@@ -0,0 +1,66 @@
+local Object = require "classic"
+local Slider = Object:extend()
+
+active = false
+
+function Slider:new(x, y, w, h, limit)
+    self.x = x or 0
+    self.y = y or 0
+    self.w = w or 0
+    self.h = h or 0
+    self.knobw = 8
+    self.knobh = 16
+    self.knobx = self.x
+    self.knoby = self.y
+    self.active = false
+    self.level = 0
+    self.limit = 255
+end
+
+function round(n)
+  return math.floor(n + 0.5)
+end
+
+function Slider:update(dt)
+    mousex, mousey = love.mouse.getPosition()
+    self.level = round(((self.knobx-self.x)/self.w)*255)
+    
+    if self.level < 0 then
+        self.knobx = self.x
+        self.level = 0
+    elseif self.level > 255 then
+        self.knobx = self.x+self.w
+        self.level = 255
+    end
+    
+    if love.mouse.isDown(1)
+    and mousex >= self.x
+    and mousex <= self.x+self.w
+    and mousey >= self.y
+    and mousey <= self.y+self.h
+    and not active
+    and self.active == false then
+        self.active = true
+        active = true
+    elseif love.mouse.isDown(1) == false then
+        self.active = false
+        active = false
+    end
+    if self.active then
+        self.knobx = round(
+            (math.min (math.max(self.x, mousex), self.x+self.w)
+        )/(self.w/255)
+        )*(self.w/255)
+    end
+end
+
+function Slider:draw()
+    love.graphics.setColor(1, 1, 1)
+    love.graphics.rectangle("line", self.x, self.y, self.w, self.h)
+    love.graphics.setColor(237/255, 86/255, 83/255)
+    love.graphics.rectangle("fill", self.knobx-(self.knobw/2), self.knoby-(self.knobh/3), self.knobw, self.knobh)
+    love.graphics.setColor(1, 1, 1)
+    love.graphics.print(self.level, self.knobx-4, self.knoby-20)
+end
+
+return Slider