Post Process Blend Weight acts as Boolean, no fade in/out
Well, after 5 hours of researching various threads and posts, I've exhausted myself trying to come up with a solution, and so I must ask for assistance.
I'm using UE4.12.5.
I'm creating an infinite hallway in one direction, and in order to hide the teleport I need to fade the background to a solid color. It's an extremely harsh transition without the ability to fade in the post process effect.
You can see my setup here:
The blueprint above holds the Post Process and a trigger box. When the player enters the box it would fade in the Post Process effect shown below using the timeline and a float track.
Here's the fade out material I used:
Here's screenshots of the issue:
But no matter what values are set, it acts as a Boolean, only on/off.
Okay I just spent another hour doing research before posting. I think I narrowed down the problem.
I tested blend weight and blend radius on a simple post process volume (I just made the screen tint blue) and it worked flawlessly.
So it seems the problem is more specifically located in the Blendables Array weight. I found threads with a similar issues:
Any solutions? If I've been unclear or can provide any additional information that may be useful, please let me know. This post was my last resort :(
Thanks in advance.
I have been running some tests and am not getting the same results you are reporting. I believe the issue you are experiencing has to do with your set up. Essentially if you want to blend from one post process volume to another with a clean linear fade, you need to have and unbound (global post process), and a bound post process volume.
You would then want to move towards the bound post process volume, and either use the Blend Radius to blend linearly to the bounding box, or use the Blend Weight to blend from 0 to 1 while inside the bounds. Below is an example of the scene I tested with the results of my blending.
Blend Weight 0.0
Blend Weight 0.5
Blend Weight 1.0
Notice how I am inside the volume, it has a higher priority than the Unbound Post Process volume, and when sliding the Blend Weight, I get a gradual and linear change between the Unbound effect and the Bound effect.
Post Process Material
For my material I simply multiply the scene by a color to get the color shifts. I then instance my material and assign a unique instance into the blendable for each volume. Now I am free to use the Blend Radius, Blend Wight, or the Color Overlay scalar parameter to properly blend in the desired effect/color.
Let me know if you have further questions or need additional assistance.
answered Sep 01 '16 at 02:40 PM
I ran into the same problem, but in the editor. The sliders to blend/fade Post Process Materials inside the Post Process Volume Details panel acted as Boolean (0 = off, !0 = full effect) on most of my Post Process Materials.
and finally figured out how to get the Slider and general PP-Material Blending to work:
[rant] This is a usability nightmare [/rant] While experimenting with PP Materials I noticed that some other Scalar Parameters magically hooked themselves to the blend weight. I have yet to figure out the pattern, because they are neither 0 to 1 ranges, nor default to 0.0, nor did they influence the Vanilla Input at all (And I don't even want the #%&$ blend weight to control my texture scale parameter!) ... So there are other ways to get the blend weight going correctly...
Follow this question
Once you sign in you will be able to subscribe for any updates here