Post Processing Primer for Unity
What is post processing?
“Post-processing is a generic term for a full-screen image processing effect that occurs after the camera draws the scene but before the scene is rendered on the screen. Post-processing can drastically improve the visuals of your product with little setup time.
You can use post-processing effects to simulate physical camera and film properties.”
Essentially, post processing are visual effects that generally speaking, are applied to the entire screen in a scene.
These effects allow us to give our games more “feel” to suit the circumstance and have in-depth optionality for us to customize to taste.
A thousand developers can use Color Grading and all wind up with vastly different results.
Combining various post processing effects is an even more powerful tool for achieving the desired feel or look of your game.
Additional post processing effects can be made by the game developer, or purchased from the Unity Asset Store courtesy of game developers who have focused on this important aspect of game development.
This is especially advantageous for indie developers due to their low cost-of-entry.
The large customer base pushes down the price to be extremely affordable!
Beautify, Prism, and Scion are all popular Unity Asset Store post processing packages for Unity.
Unity Post Processing Package
There are a variety of post processing effects out there, and Unity’s post processing package provides the most popular and useful.
We’ll briefly go over each one.
Ambient Occlusion
“The Ambient Occlusion effect calculates points in your scene that are exposed to ambient lighting. It then darkens areas that are hidden from the ambient light, such as creases, holes, and spaces between objects which are close together.”
Anti-aliasing
“The Anti-aliasing effect softens the appearance of edges in your scene. To do this, it surrounds the edge with similar points of color. This reduces the jagged effect caused by aliasing.”
Auto Exposure
“The Auto Exposure effect simulates how the human eye adjusts to changes in brightness in real-time. To do this, it dynamically adjusts the exposure of an image to match its mid-tone.”
Bloom
“The Bloom effect makes bright areas in your image glow. To do this, it creates fringes of light that extend from bright areas in your image. This simulates the effect a real-world camera gives when light overwhelms the lens.
The Bloom effect also has a Dirtiness feature, which you can use to apply a full-screen layer of smudges or dust to diffract the Bloom effect.”
Chromatic Aberration
“The Chromatic Aberration effect splits color along boundaries in an image into their red, green, and blue channels. This reproduces the effect a real-world camera produces when light refracts and causes the wavelengths to disperse in the lens.”
Color Grading
“The Color Grading effect alters or corrects the color and luminance of the final image that Unity produces. You can use this to alter the look and feel of your application.”
Deferred Fog
“The Deferred Fog effect simulates the look of fog or mist in outdoor environments. To do this, it overlays a color onto objects depending on how far away they are from the Camera.”
Depth of Field
“The Depth of Field effect blurs the background of your image while the objects in the foreground stay in focus. This simulates the focal properties of a real-world camera lens.”
Grain
“The Grain effect overlays film noise onto your image. Film noise is the effect that real-world cameras produce when small particles in the camera’s film give the image a coarse, unprocessed effect. Unity’s Grain effect is based on a coherent gradient noise. This gives your game a gritty effect that simulates the imperfections of film.”
Lens Distortion
“The Lens Distortion effect simulates distortion caused by the shape of a real-world camera lens. You can adjust the intensity of this effect between barrel distortion and pincushion distortion.”
Motion Blur
“The Motion Blur effect blurs the image in the direction of the Camera’s movement. This simulates the blur effect a real-world camera creates when it moves with the lens aperture open, or when it captures an object moving faster than the camera’s exposure time.”
Screen Space Reflections
“The Screen Space Reflection effect creates subtle reflections that simulate wet floor surfaces or puddles. It reflects both static and dynamic GameObjects to create realistic reflections.
Screen Space Reflection replaces specular highlights on a surface, which makes it an ideal effect to limit the amount of specular light leaking.”
Vignette
“The Vignette effect darkens the edges of an image. This simulates the effect in a real-world camera lens caused by thick or stacked filters, secondary lenses, or an improper lens hood. You can use the Vignette effect to draw attention to the center of an image.”
In the next article, we’ll install and apply Unity’s Post Processing package in our prototype project.
