Highlights now support Outlines on Mobile [Client Beta]

I feel like there should be an option for outline thickness only visible in desktop, that way you won’t have to deal with the optimizations of mobile


I find it less intuitive to only highlight the head of a character than using highlight as groups.
It isn’t possible to remove the limit unless you want to play games at <30FPS.

Everything can’t always be pre-built, without any limit and super easy to use, every game engine have their own limitations and constraints, developing around these is a part of our job.


I don’t think you understood. I don’t care if you think that highlighting only the head of a character is intuitive or not; I’m saying that you can’t even accomplish that with the current limit that is being forced upon us.

About your point with the FPS, obviously every developer has to watch out that their game runs well; however, this is what I also mentioned in my original comment…


You can. I told you how. It’s pretty easy and have little to no impact about physics or memory.

Maybe your example wasn’t the best though. A more impacting example would be to have a different highlight with a different color on over 31 characters which isn’t possible.

Every developers don’t put efforts to optimize their game on low end or mobile devices, everyone do not have the same computer than you, it can run very well on your pc but badly on other.


Hah… what do you imagine that we are doing? :sweat_smile:

We are doing exactly that! Changing rendering engine piece by piece. Pretty much constantly. Roblox graphics engine used to be developed by 3 people and now there is ~20.

Some changes may not be that visible, but engine is more stable and faster every month. Roblox is not an engine that you ship version 1 and then version 2. It is one engine that is evolving and changing.


I’ve heard plans of Roblox deprecating OpenGL 2.X devices; would this deprecation lead to a reconsideration of the minimum constraints?

I’ve no idea as to the actual statistics and this is just me spitballing, but from the android statistics, it seems that 4.1% of the android users are still on OpenGL ES 2.0:

I’ve been unable to find similar statistics for iPhones and other iOS devices, however assuming they’re both 4.1%, it would lead to a significant drop of devices that Roblox supports. Due to this, I can imagine OpenGL ES 2.0 support won’t be dropped anytime soon? It’s understandable if this isn’t anything you can comment on, I’m simply just sharing statistics for the curious.


We dont need to deprecated gles2 to increase highlight limits. It is also not only gles2 that has the issue. It would be mostly a some work to support it as it is tad more complex. And that is it. More important are overall performance consideration.

I dont want to make any promises at this point, but we are really considering unlocking it. Including doing the extra work for low end devices to support it. But this is not an official promise :slight_smile:


I do have one question. I’m not sure if you guys are already using it but I don’t think you are so if you aren’t, is it possible to use a JIT compiler for Luau to make it run even faster in game?

If it is, I think it would be a really good update for pretty much everybody. While it may not be very beneficial to small scripts, things like terrain generation algorithms would be so much faster, and in most cases, actually usable in a game.

You could generate data for, lets say, terrain chunks and calculate cell materials based on the biome/terrain/conditions or whatever you want it to be based off of SO much faster, and in MUCH larger quantities.

Luau native code was definitely a step forward, but I still don’t think it’s quite fast enough :confused:
If it is possible to add Luau JIT I and probably quite a few others would love to see it!

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Both increasing the highlight limit and allowing us to change it to per highlight visible would be amazing changes! Per highlight visible alone would pretty much solve most of my personal* issues regarding the limit

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These are some bugs present in the recent highlights update. The two bugs I discovered occur on mobile.

highlightInvertRepro.rbxl (55.2 KB)

Here’s the place on PC:

This is the same place on mobile:

For the sphere on the right, basically, when layering meshes, occluded highlights are rendering on top of neon parts within unhighlighted meshes

For the sphere on the left, a part layered within three layers of occluded highlighted inverted meshes renders underneath the occluded layers.

Woah, you seriously added something useful! But highlight still work with bugs.
But why it update has been didn’t added before?
Well now i can use highlight outline and don’t bother for moblie user!

Thank you for flagging this issue @700000002!
We’ll look into it and follow up!

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It was not added before because it is actually really hard thing to do. Just so you get an idea: running the “basic” PC/desktop highlights on mobile it would cost around 8ms on a decent device (say 4 years old ipad). We invented a new way to compute highlights just to support it on mobile.

We care. But in case of highlights this was way more complicated than it may look like from the outside.

What bugs? Please report. In past 6 months we fixed 17 highlights related bugs

Bug with Highlight even on computer, i had highlight is was shown where it shouldn’t show even just in the roblox studio, i unselected object but still show. (it more like it happens random) i don’t report because i can’t tell more details.

I believe those selection related issues have been fixed already, lmk if there’s any other issues still present today!

I understand what you’re saying, and I wish more people understood. Though I am not an engineer, I know it is very challenging and complex, especially when you’re trying to design future-proof frameworks that are performant, work across low-to-high end devices, work across platforms, all whilst attempting to carefully not ruin the millions of other components that make up the Roblox visual engine. Hopefully this isn’t off-topic but great job Team, and I’m really looking forward to what’s to come!

There have been a flag for a few years now to increase the range limit to 120. Recently their have been some fixes to fix the flicker that the long range causes.

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