Learn how to add a joystick element to your mobile game. Learn how to create the movement illusion of a joystick and how a joystick can be constructed from a stationary image and a movable image.

Learn how to change the appearance of a button when pressed. Learn how to load multiple image-textures in OpenGL ES and how to activate different textures when a button is pressed.

Learn how to add realism to a 3D model by using Normal Mapping techniques. Learn how to calculate the tangent and bitagent vectors necessary to create a Normal Map space.

A skybox is a panoramic view representing a scenery. It can add realism to your game at a low performance cost. Learn what a skybox is, how it works and how to implement it using OpenGL ES.