require 'gosu'

require 'opengl'
require 'glu'
require 'glut'


include OpenGL
include GLUT
# OpenGL.load_lib()
# GLUT.load_lib()

class ExecuteOpenGl
  # def self.init_scene
  #   glEnable(GL_TEXTURE_2D)
  #   glShadeModel(GL_SMOOTH)
  #   glClearColor(0,0,0,0.5)
  #   glClearDepth(1)
  #   glBlendFunc(GL_SRC_ALPHA,GL_ONE) #see nehe08
  #   glEnable(GL_BLEND)
  # end

  # def self.add_perspective_to_scene
  #   glMatrixMode(GL_PROJECTION)
  #   glLoadIdentity
  #   gluPerspective(45.0, width / height, 0.1, 100.0)
  #   glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST) #see nehe07
  # end

  # include Gl
  # include Glu 
  # include Glut

  def draw background, projectiles, player
    # @zoom = -14
    Gosu.gl do
      # init_scene
      # glEnable(GL_TEXTURE_2D)
      # glShadeModel(GL_SMOOTH)
      # glClearColor(0.0, 0.2, 0.5, 1.0)
      glClearColor(0.0, 0.0, 0.0, 0.0)
      glClearDepth(0)
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
      # glBlendFunc(GL_SRC_ALPHA,GL_ONE) #see nehe08
      # glEnable(GL_BLEND)

      # glMatrixMode(GL_MODELVIEW)  #see lesson 01
      # glLoadIdentity              #see lesson 01
      # glTranslatef(0, 0, -13)   #see lesson 01
      background.exec_gl

      glShadeModel(GL_SMOOTH) # selects smooth shading
      glLoadIdentity              #see lesson 01
      # puts "-projectile.get_draw_ordering - 10: #{-projectile.get_draw_ordering - 10}"
      glTranslatef(0, 0, -13)   #see lesson 01
      @ambient_light = [0.5, 0.5, 0.5, 1]
      mat_shininess = [50]
      glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess)
      glLightfv(GL_LIGHT1, GL_AMBIENT, @ambient_light) # sets ambient light for light source
      glEnable(GL_LIGHT1)


      projectiles.each_with_index do |projectile, i|
        glMatrixMode(GL_MODELVIEW)  #see lesson 01
        glLoadIdentity              #see lesson 01
        # puts "-projectile.get_draw_ordering - 10: #{-projectile.get_draw_ordering - 10}"
        glTranslatef(0, 0, -13)   #see lesson 01
        # glTranslatef(0, 0, -14)   #see lesson 01
        projectile.draw_gl
      end
      player.draw_gl_list.each do |item|
        glMatrixMode(GL_MODELVIEW)  #see lesson 01
        glLoadIdentity              #see lesson 01
        glTranslatef(0, 0, -13)   #see lesson 01
        item.draw_gl
      end

    end
  end
end