Understanding the Basics of Post Processing [Unity]

This article explains post-effects, which are effects that are applied to video and images, and Post Processing, which is an asset for implementing post-effects in Unity.

Post-Effects refers to applying effects (filters) to “the result of rendering the information (3D model, lights, etc.) that is reflected in the camera”.

Think of a camera application such as “SNOW” or an image editing software such as “Photoshop”.

In Unity, you can use its Post Processing Stack by downloading and importing it from the Package Manager.

In summary:

  • post-effect
    • The filters and effects themselves
  • Post Processing Stack v2
    • Assets needed to recreate post-effects in Unity and STYLY

I think it’s easier to understand if you imagine it as

To be more specific, you can add a screen effect like the one in the image below.

Post Effect None

Post-Effects Yes

(The 3D model of the trees is a free asset from Unity, Dream Forest Tree)

 

Master the simple steps that will instantly improve the quality of your graphics!

Sample

This is a space that uses Post Processing. Experience it.

 

Import to Project

Import using the Package Manager.

First, import the Post Processing Stack v2 into our project.

Click on the Package Manager from the Window tab at the top of Unity.

(Select Package Manager from the Window tab)

When the Package Manager opens, select Post Processing from All Packages and click the Install button at the bottom right corner to install it.

(Select Post Processing from All Packages)

When the installation is completed, a check mark will appear on the screen.

(When the check mark appears, the installation has completed successfully)

Try the Post Processing Stack in action

Requirements in advance

Introduce the Post Processing Stack v2 into our scene.

Select MainCamera on the Hierarchy window (hereinafter referred to as the Hierarchy).

Click on Layer at the top of the MainCamera inspector window (“Inspector”) and then click Default from the list that appears (Default is selected by default).

(Select “Default” for Layer and click on it)

Return to the MainCamera inspector, click on add Component at the bottom, type Post in the search bar that appears, and then click Post-Process Layer.

Post Processing Layer only.

This will add a Post Process Layer component to the inspector.

Change the Layer tab in the Post-Process Layer to Default.

(*2020/05/18 Generally, it is best to prepare a separate layer for Post Process, but due to STYLY specifications, it is not possible for users to create a new layer. However, there is a good chance that STYLY will provide a new layer for PostProcess layers in the future with an update. In that case, we will add a note).

(Set to “Default” because the default value is nothing)

The next step is to create an object to manage the screen effects for PostProcess.

Right-click on the hierarchy and select Create Empty to place the new GameObject

 

Click on add Component in the Inspector of the generated GameObject.

Type Post in the search bar to add the Post-Process Volume component.

(Add Post-Process Volume only)

Check the “Is Global” checkbox in the Post-Process Volume you added.

Click the New button on the right side of the Profile item.

(Clicking the NEW button will create a new profile for Post-Process)

That’s all the prep work done.

Now let’s add some post effects!

Introduction to Effects

The Post Processing Stack v2 has several on-screen effects: in the Post-Process Volume, click “add effect… in the Post-Processing Volume, and then select Unity to see the various effects.

There are some profiles that are incompatible with VR, as I will show you one by one.

 

  • Depth Of Field
  • Motion Blur
  • Chromatic Aberration
  • Grain
  • Vignett

 

Note that some settings are not compatible with VR.

Also, you can’t use ‘Screen Space Reflection’ in STYLY.

Let’s see the effect of each effect keeping the above in mind!

【Ambient Occlusion】

It is a screen effect that casts a shadow on the corner of an object to make it look like “reality”.

This effect is useful for recreating a real space in VR, such as a school classroom or town.

 

Ambient Occlusion None

 

Ambient Occlusion Yes

【Auto Exposure】

This effect is capable of automatic exposure adjustment. This effect can express the dark and light acclimation that occurs when moving from a dark room to a light room.

【Bloom】

This is an effect that can emphasize light. This effect is good for making certain objects glow in dark spaces and “neon” effects.

It’s probably one of the most frequently used effects, and once you master it, any space can look pretty good.

(*More on this later)

Bloom None

 

Bloom Yes

【Chromatic Aberration】

Chromatic Aberration effect

Chromatic Aberration None

 

Chromatic Aberration Yes

【Color Grading】

This is a color correction function. You can add a reddish tint to the screen in the sunset space and a blackish tint in the night space.

【Depth of Field】

It can represent the “focus” of an image taken with a real camera, also known as “depth of field”.

(*It is not recommended to use it in VR)

Depth of Field None

 

Depth of Field Yes

Grain

This effect can add noise to the screen. This effect replicates the noise that real cameras make in dark places.

 

Grain None

 

Grain Yes

【LensDistortion】

This effect can reproduce the distortion of the lens. You can create a fisheye lens-like effect.

(*It is not recommended to use this effect in VR)

LensDistoriton None

 

LensDistoriton Yes

【Motion Blur】

An effect that adds blur to a moving part of the image. This effect is used to express a sense of speed.

(*It is not recommended not to use this effect in VR)

Motion Blur None

 

Motion Blur Yes

【Screen Space Reflection】

(*Not available in STYLY)

This effect is designed to create a “reflection” of an object in real time.

Note that this effect can only be used when the rendering setting is DeferredRendering, and objects that are not reflected in the camera will not be reflected.

Screen Space Reflection None

 

Screen Space Reflection Yes

Vignette

This effect darkens the edges of the screen. You can use this effect to create a slightly retro look or to blend in with a space.

Vignette None

 

Vignette Yes

This is a brief introduction to the effects available in PostProcessing Stack v2.

These effects can improve the look and feel of your images, so make sure to use them!

Introduction to Bloom

Let’s take a look at the actual effect settings.
Select the Bloom with the best screen effect.

When you add Bloom to PostProcessVolume, it looks like this.

First of all, check the checkboxes in the red frame.

(*You don’t have to turn on all the checkboxes in the red frame. You can lighten the load by turning on only the items you want to use.)

The following is an overview of the “Intensity” settings, starting with “Intensity” at the top.

【Intensity】

The intensity of the light. You can increase the intensity of the Bloom by raising this value. Set the value to your liking.

(Note that raising the Intensity value too high will cause the image to become blurry)

【Threshold】

This is the threshold item. Bloom will not be applied to light whose brightness is less than the value you set here.

(Change the Threshold with Intensity 20)

Soft Knee

This is called “Soft Knee” and the value can be changed between 0 and 1.

The closer the value is to 1, the closer the effect is to the threshold even if it doesn’t exceed the threshold, the more the effect is applied.

(*The default value of 0.5 is not a problem in most cases)

Clamp

This is the item to set up the amount of Bloom per pixel.

(*If you don’t have any problems, you can use the default value.)

Diffusion

It can be adjusted on a scale of 1 to 10. The closer to 1, the less diffuse the light is, and the closer to 10, the more it spreads across the screen.

【Anamorphic Ratio】

You can set up the distortion rate of Bloom, with -1 to 0 being the vertical direction and 0 to 1 being the horizontal direction.

(The default value “0” is fine unless you need it)

Color

You can set up the color of Bloom, which uses HDR color picker to give the specified color tone.

Fast Mode

 Diminishes Bloom’s rendering quality and prioritizes performance.

 

【Dirtiness】

It expresses the dirt and dust on the lens.

You can refer to the image file with Texture and adjust the intensity of the dirt with Intensity.

That’s all about Bloom.

Upload to STYLY

Upload the Post Processing scene you created, pre-fab, to STYLY.

Create a STYLY account

Here’s how to create a STYLY account

Here’s how to upload a pre-fab from Unity to STYLY

Here’s how to upload a scene from Unity to STYLY

What to do when a scene or prefab is too heavy to upload to STYLY