This chapter will unfold the endless possibilities of a scene and its image-based effects, which are widely used in the field of data visualization and after effects. Practically, objects are represented as a set of vertices in the 3D space. As the number of vertices go higher, the time complexity of the scene increases. Moreover, representing the object in terms of an image has a time complexity proportional to the number of fragments in the scene. Additionally, many effects can only be efficiently possible in the image space rather than implementing in the vertex space, such as blurring, blooming, cloud rendering, and so on.
The term post screen processing is a texel manipulation technique applied on an OpenGL ES scene once it's rendered. To be more specific, the scene is first rendered to an offscreen surface where effects are applied. Then, this manipulated offscreen texture is rendered back to the screen surface.
In post processing, the outcome of a given texel is affected...