Blurred environment reflection

Here is a shader that is intended for real time usage. It takes advantage of passing custom derivatives to the texture lookup function. This is quite useful to produce blurred environment lookups. This enables you to produce more realistic looking surfaces because it allows you to mimic real-world surfaces in a much better way.

Since it is the 31st of December and I am about to dive into the next new year's party I will keep this post short... ;)

Idea:
Create an shader for real time usage that blurs the reflection based on the incident viewing direction.

Different Blurs of the reflection:

• From inner to outer 
• from outer to inner 
• controlled by another texture

Observation:

• If you take a look at a blurry surface, the reflection gets crisper when you look at it from a grazing angle. I observated this in detail a couple of years ago when I was working at a post production company and we were doing a promotion video for a big steel industry company.
  My colleagues back then told me that I was too meticulous. Maybe I was, but when your passion is building shader graphs its the observation and implementation of these small details that give the extra punch to your shader.
• Also, reflections appear to have less saturation which, depending on the surface is not true. However, I added a control to the shader that allows you to drive the saturation of the lookup.

Other features:

• The environment blur can be inverted
• A constant blur can be applied too
• Amount of the incident blur can be controlled

Tip:

• Use the constant blur to shift the incident blur

Find the shader code on the mental images forum

Increasing the intensity of the constant blur (controlled by a texture) can yield
stunning looking corrosion effects. Also the reflection saturation has been
reduced for these screenshots.

Happy New Year Everyone!