Is it as bad if you change the color/material of the character?
Yes, even if I change the concrete to a red or purple concrete it is happening.
Also with any other color on a single colored material.
This is a bigger issue when just this wall …
This happens when you lay down grass, a lot of it. No matter what AA you are using, you get massive ghosting. I have tested this 100 ways and the results are the same. Doesnt matter the grass type, LOD, or, whatever we want to throw at it as an excuse. The AA methods mixed with , i believe, the lighting, are what causes this. Notice that when your in the shaded areas, the effect is a lot less, slightly noticeable. In the direct sun areas, the effect is easily seen, even with the video being compressed.
I have yet to have someone give a legit answer on this other then “lower the quality”. TX helps with the grass issue, but, the rest of everything else suffers. FX resolves a lot of the AA issues that are caused from TX, but, the large amount of items (grass i my case) cause that ugly ghosting. Its not singled to just the character, the trees will ghost as well when your running past (tree ghosts on the grass along with the player ghosts).
This is artefact of Temporal AA.(used for ssao and ssr too)
Basically ue4 use temporal AA algorithm that clamps last frame contribution using current frame 3x3 RGB bounding box.(neighborhood clamping) Worst case scenario is that you have 2x2 black and white checker pattern at background. Then algorithm just allow ghosting everywhere.
Actual implementation is pretty compex and high tech but you can see the code yourself and there is lot of presentations where you can get more information.
so if i read it right, ghosting is just a side effect that we have to deal with at this time …?
Yes. It’s really annoying side effect. There are some non general hacks that can be used for antighosting. Uncharted 4 marked some most artefact ridded object with stencil and then those mask bit’s can be used at TXAA shader to choose do you want aliasing or ghosting per pixel.
The ThirdPersonTemplate does this by default in 4.13.1
All should do this due to the AA shaders they use - TXAA “resolves” this, but, looks like im going to be digging in to see what i cna do to minimize this without 50 hours of work more into one thing (ghosting) …
The “Responsive AA” material checkbox does that object marking, disabling the temporal AA in that region using the stencil buffer.
However, it only works for translucent materials (they seem to use the stencil buffer for other things in the opaque pass), so you may have to add an extra copy of the mesh with a special translucent material that outputs nothing in order to use it in general.
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I only get ghosting that’s maybe a few inches of centimeters behind the character in the third person template, that easily looks like a bit of motion blur. I ran around the entire level and checked every wall. I wonder if there’s a driver issue or bug making it worse for some people.
Slower frame rate makes it more visible.
I would say MS + FPS on the low = more ghosting
As discussed - motion blur removed about 95% of my ghosting.
Setting the default 0.5 with an unbound PP … worked nice. Unless the players are whipping in circles while running at 200% normal speeds, its hardly noticeable.
With cough help cough ^^ … i made the decision to enable motion blur. Well worth the massive help in the ghosting.