Neon rendering is acting like it’s applying multiple glow layers every few frames. You end up with REALLY bright neon that has a ghosting effect as you move around. It only happens in Studio, not the Roblox Player, and it’s with any neon parts.
http://i.imgur.com/5QMlGXE.gif
I’m on the latest version of macOS, I’ve noticed it going on for the past few weeks, and I believe it only started after I updated.
Is this happening with any quality level where Neon is visible, or with some specific ones? What’s the exact macOS version that you have, and what are the specs of your Mac?
Too bad it’s not a feature, motion blur-esque effect would be cool
Apologies for the late reply, thanks for responding.
Yes it happens at even Quality Level 1.
I’m running a mid-2012 15" Retina Macbook Pro. It’s got the dedicated graphics (NVIDIA GeForce GT 650M), 2.3 GHz i7. 8 GB Ram.
I’m running macOS 10.12.1
At quality level 1 - so even if neon glow is inactive the ghosting still happens?
Does it happen for both transparent and opaque parts or only for transparent?
Does it happen for bright transparent non-neon parts or is this limited to Neon?
Yes, even without the neon glow, I’ve got ghosting.
Happens with transparent or solid neon parts. It is limited to only neon parts. Bright white plastic for example doesn’t do anything.
It makes usual neon colors brighter than normal too. Here’s a Really Black neon brick
Bonus Gif, you can see it’s a black part VERY briefly before the layers of neon stack on top. You can also see the tree branches from the previous frame.
Looks like I’m not alone!
https://twitter.com/DarthBlox/status/794372845916680192
Also, a new interesting gif. I haven’t seen this behavior before. The sides of the window are somehow impacting how the neon renders.
Any updates on this?
Still unclear what to do with this - we can only investigate this if it happens to somebody in the office basically, and we haven’t had anybody with that issue. I’m not sure OTOH how many of us are running Sierra, I know I am and haven’t ever seen this 
Is there anything I can do to help you guys find it? I’m finding myself not using neon in newer builds because I don’t know what it’s going to actually look like.
I’m not really sure. I’m trying to see if anybody at HQ can reproduce this but so far it does not seem like it.
So if you add a “really black” neon part, it doesn’t immediately become white, right? that is, it starts as black and quickly fades to pure white? What happens if you resize the window after it does - does the process of fading restart or does it stay pure white?
It’s only really black for a split second, before turning greyer and greyer until it’s eventually pure white with ghosting issues. This whole process happens in under a second. I’ll try to get a video later if you need it.
Resizing the window does nothing, HOWEVER, simply clicking the top of the roblox studio window (where the minimize, fullscreen, etc buttons are) will change the part back to Really Black once I release the click. This too only lasts for a split second though, before turning greyer to white.
Hmm, ok. I have a hunch.
If you have a Neon part and add Blur effect with the max blur size, does the outline of the part become clearly visible despite the blur?
Alright, cool. I now know what is happening, if not why. I have a few ideas for fixing this. I’ll try to get some Mac-specific fix together that may or may not help; if it doesn’t there’s a way to fix it in the color correction pipeline but this is kinda unfortunate because we’d need to special case something.
Of course the fun part is that since I can’t repro, we’ll have to iterate by me shipping fixes and you checking them… Oh well.
Just want to note here that we got a repro for the Neon issue in house thanks to @spotco. We’ll investigate and figure out how to fix it.
edit: damn it, the repro disappeared when the laptop with the repro got upgraded from OSX 10.10. Oh well. We’ll use the backup plan of shipping fixes that may or may not help and slowly iterating towards something that works, I guess
Since the issue is Studio-only it’s also possible that the coming-soon Qt5 upgrade will fix this.
I’m back zeuxcg, noticing different behavior. Neon brakelights are remembering what the studio website page was previously on. Panning around looks like this. The neon is at half transparency so it’s not blown out on my screen.
You thought I was done @zeuxcg?!? THINK AGAIN!
Except this time around I’ve got some good news,
Neon is almost working again!
One very important thing to note. I checked my Studio files and found Studio hadn’t been updated since January 20th 2017. I was never prompted. What made me check my version was when I realized I still had the old brick and plank textures. I deleted studio and reinstalled. Since then is when I’ve been getting better luck with Neon.
Anyways, I can still see the roblox website in all neon bricks like the gif I posted above. What has changed though is that sometimes opening a script will completely fix the problem. Strangely enough, it sometimes doesn’t fix the problem, but instead will turn my neon bricks black.
So I’ve spent today trying to narrow down why this happens only part of the time. How can I get around this neon bug until it’s 100% gone.
This is what I’ve found. If you have any questions please let me know! I’ve never been so excited to see neon, it’s as if the feature was just announced. I can finally build with it again!
Thank you for being so involved with this issue!
Uh oh, this is a persistent issue. I checked in some changes earlier this year but apparently they changed nothing; we also upgraded to Qt 5 but apparently that also didn’t fix the issue (but may be the reason why you now see different behavior).
Without being able to debug this I feel like the only step we can take now is to change the post effect pipeline to kill output alpha so that it’s impossible for the window to get transparency. Unfortunately we have to keep the alpha for thumbnails to work so this means forking some code a bit…
Ah, hmm, there’s one more thing I can try (which will ship in 1.5 weeks). If that doesn’t help either, we’ll use the nuclear option.
