Issue with alpha blended/additive shader

[dimitar.tsaprev]

Hello!
I've been using Amplify Motion for quite a while now and it has served me well until today when I noticed something.
I have a big tube model which has a material that uses an alpha blended shader. I found out that amplify motion did not work when translating the camera backwards and forwards as well as sideways. There was no blur effect at all. I tried rotating the camera and when I rotated, I got motion blur but translation did not produce any motion blur at all. I switched the shader to an alpha cutout and I immediately got motion blur on translation.
I fiddled a lot with the settings of amplify motion and also the shader that I'm using but I couldn't get the blur to work properly.
Can this be fixed or amplify motion is not supposed to work with alpha blended or additive materials ?

Thanks!

[Ricardo Teixeira]

Hello Dimitar,

Thank you for using Amplify Motion, we really appreciate it.

AM relies on the "_Cutoff" shader property name for the alpha-test reference value, only opaque and alpha-test surfaces are currently supported. What kind of asset are you using it on? Screenshots would be great, we are always looking for news ways to improve Amplify Motion.

Thanks!

[dimitar.tsaprev]

Hi and thank you for the reply! Amplify motion is a wonderful plugin.
I'm using it on a procedurally generated wormhole tunnel. The player is inside that tunnel and flies around it really fast.
This is a screenshot of how it looks:

If I do a barrel roll, I would get a perfect blur but just flying forward in the wormhole will not produce any blur. I'm currently not at the office but I have an idea: I could try applying another material to the wormhole renderer which is a fully transparent alpha cutoff material. I've seen the plugin produce blur on surfaces that are right behind a surface with an alpha cutoff shader. I'll report the results when I do it!

[dimitar.tsaprev]

I tried adding a cutoff material which is fully transparent but sadly it didn't work. I will have to keep looking for a workaround for this. Are there any plans for updating the plugin to support alpha blended and additive shaders in the near future ?

[Ricardo Teixeira]

Hello,

That is unfortunate. We do have a few major improvements currently in development for Amplify Motion but they are still a couple of months away. We do intend to offer more control over the actual blur effect, I will register you interest and get in touch as soon as we have any updates.

In the meantime I recommend using a combination of standard Radial Blur (an amount based on the ship velocity) and Amplify Motion for all other blur effects, let us know if that works for your project we would love to hear from you.

Thanks!

[dimitar.tsaprev]

Thank you very much! Indeed, I was thinking about using radial blur if all else fails. I'm happy that you registered my interest in this and I would really love to see it working with alpha blended shaders some time in the future

[Ricardo Teixeira]

Awesome, we will be in touch as soon as we have any updates.

Thanks!