LET OP: mapnaam in de video is fout, moet zijn: 03_badeend_layers https://www.youtube.com/watch?v=2JizIFo-MCE&index=1&list=PLOlTG69MDgfy1AuGPm7yKxeGs1clUvOW_
https://www.youtube.com/watch?v=k0WZpYp7lgM&index=2&list=PLOlTG69MDgfy1AuGPm7yKxeGs1clUvOW_
https://www.youtube.com/watch?v=rpOzg7KMSmw&list=PLOlTG69MDgfy1AuGPm7yKxeGs1clUvOW_&index=3