Replace Perlin noise with Ruby-OpenGL2 for shader support; update Gemfile and remove related noise generation code.

Gemfile

@@ -1,4 +1,4 @@
 source "https://rubygems.org"
 
 gem "gosu"
-gem "perlin"
+gem "ruby-opengl2"

game/scene.rb

@@ -5,13 +5,10 @@ require_relative 'enemy/handler'
 require_relative 'weapons/handler'
 require_relative 'character'
 
-require 'perlin'
-
 class Game < Scene
   def initialize
     super
     @font = Gosu::Font.new(24)
-    @noise = Perlin::Generator.new(rand(1...1000), 1.0, 1)
     @floor_image = Gosu::Image.new("assets/images/floor.png", retro: true)
 
     @maze = Maze.new

run

@@ -2,6 +2,6 @@
 
 # Dependencies
 # Gosu for rendering and input
-# Perlin noise for fog effect
+# Ruby-OpenGL2 for shaders
 
 load 'main.rb'