Unity Slides From SIGGRAPH Are Up, Unity Not Doing Vulkan Just Yet

Yeah, they better deliver on OpenGL which I see to being around for quite some time.

From the slides (since there's now way currently to actually see the live presentation), it would seem their ONLY focus is DX12. That really sucks. DX12 will only benefit the Windows Desktop platform and possibly Xbox One.

This leaves out:
1. Android
2. iOS
3. Linux desktop
4. Mac OSX desktop

They write in the slides that DX12 forced them to cleanup code, which benefited all the other platforms as well. I doubt it's anything truly significant though.

This will mean near future versions will still have the hampered OpenGL 2.1 code they're using for Linux. This was a disappointment to me, since I make use of Unity3D almost every day. I was looking forward to more OpenGL pro-activeness with the recent announcement of the Linux IDE in the works.


Last edited by Sabun on 12 August 2015 at 9:44 am UTC

But this does not mean they won't implement a Vulkan export path for other platforms. Actually, the Vulkan and DX12 will be very similar, so the adoption from DX12 to Vulkan should be very painless and straight forward for them.

Anyway, most engines will support both, a DX12 and Vulkan export path. And I see nothing wrong with that.

Code cleanup will show very significant benefits. I think they're already moving away from GL2.1, unless I'm mistaken - or at least they use extensions better so that you basically get GL3.x out of it anyway. We've already seen a lot of this with Unity 5.x, which runs much nicer than previous versions.
I rather suspect that HLSL - > SPIR-V will block them implementing Vulkan for a little while. That seems to be a large concern for them, and justifiably so.

Significant to which platforms the most? What exactly are the benefits? They don't mention it in the slides as far as I can see which is why I'm skeptical. It's extremely vague. It focused almost entirely on DX12 thus we have nothing to go off. If they can show slide after slide of changes for DX12, why not for OGL too?

From my understanding, a post of theirs from May this year states they have experimental OGL support upwards to 4.5 in Unity 5.1. Quoting them:

desktop OpenGL: all versions from 2.1 to 4.5 (desktop OpenGL support is experimental in 5.1)

This is so far the only mention of it that I can find, and oddly enough it's in a post regarding mobile. While their documentation for the scripting part of their engine is very good, I find that much of the other information regarding their engine is very difficult to discover (lots of old links lead to dead pages).

So, at least in Unity 5.1 still, it will default to the legacy GL renderer which is OpenGL 2.1 in the final build as far as I can tell. I don't see a mention of change for this in Unity 5.2 either. It would seem anything greater than 2.1 is still Windows-only right now.

This will mean near future versions will still have the hampered OpenGL 2.1 code they're using for Linux.

It will? Unity 5.2 will introduce experimental support for newer OpenGL core profiles on Linux.

The in-talk focus is on DX12 and Metal because they exist today, so people can speak concretely about implementations, benefits, drawbacks, etc.

It will? Unity 5.2 will introduce experimental support for newer OpenGL core profiles on Linux.

Could you kindly point me to where you got this information regarding Unity 5.2? I'd like to read about it further.

I can only seem to find information that says the experimental support is still not yet ready for Linux or OS X, but is already running for Windows.

Unfortunately we have to admit it that Linux still needs a lot of work to be on par with Windows Gaming and things are not moving fast enough...
Maybe I am thinking like that because I am a bit disappointed from Gamescom , was expecting Darksouls III and some other AAA titles to be available on Linux as well.... :(

Lets hope in three Months we will see major improvements and major Gaming Companies will support Linux....

Right this moment I don't have time to find it, but it trawl through the comments from the unified GL rendering system. I think it might have been in there - someone from Unity3D actually commented about it.

While there might be a GL2.1 context right now, behind the scenes there are checks for extensions, etc, that mean you're not limited to GL2.1 in reality - and improvements to that have come out of the code cleanup efforts. While official GL.3x or GL4.x might be nicer, it's not as bad as being stuck with pure GL2.1.

Thank you mirv, I think I've found a mention of it in the release notes here.

Linux: Enable experimental GL core profile mode (via -force-glcore and friends)

It's also listed as full OGL 4.5 support for the Linux standalone in Unity 5.3 roadmap here, which is awesome!

OpenGL 4.5 support in Windows & Linux Standalone and Editor

I'm not sure how it's currently activated, but it looks like the default is definitely OGL 2.1. If the current Linux game is built with Unity 5.2.03B or newer, then us players should be able to force the experimental OGL support via Terminal or Steam's launcher I think (needs verification). Otherwise it will still remain OGL 2.1.

@wolfyrion, I understand your dismay. After so many awesome releases this year, I've become impatient haha.

From the slides (since there's now way currently to actually see the live presentation), it would seem their ONLY focus is DX12. That really sucks. DX12 will only benefit the Windows Desktop platform and possibly Xbox One.

This leaves out:
1. Android
2. iOS
3. Linux desktop
4. Mac OSX desktop

They write in the slides that DX12 forced them to cleanup code, which benefited all the other platforms as well. I doubt it's anything truly significant though.

This will mean near future versions will still have the hampered OpenGL 2.1 code they're using for Linux. This was a disappointment to me, since I make use of Unity3D almost every day. I was looking forward to more OpenGL pro-activeness with the recent announcement of the Linux IDE in the works.

no, it doesn't suck even the least. unlike previous where DX and OpenGL were different in basics like simple coordinate system, this time around they are both
- based on Mantle (according to DICE developer, porting between DX12 and Vulkan is much more trivial than it was from DX to OpenGL)
- they use almost same approaches all around
- DX12 final spec is out, Vulkan is not yet
- cleanup code is significant, mostly to the fact Unity was DX centric. even difference between DX11 and DX12 is huge compared to DX12 and Vulkan

best thing Linux could do is forget OpenGL and move to next big thing as fast as possible. just implementing OpenGL in Mesa with Vulkan would solve 99% of problems OpenGL has since it would be singular implementation across all vendors and cards that are Vulkan compatible, which is most of the cards out there. maybe not as fast as native driver, but in 2 years it won't matter anyway since hardware is getting faster and faster


Last edited by vulture on 12 August 2015 at 3:06 pm UTC

So none of the big engine developers have made commitments to Vulkan so far - no CryEngine, Unreal or Unity 5. Worrisome. At the same time DX12 games will begin coming out this month (well there was technically one last month... sort off). At the same time Vulkan is not released yet. The more they take their sweet time, the more developers will get comfy with DirectX12. I wonder when do we reach the point of no return. Valve will really have to pull an ace from their sleeve or the Steam Machine premiere will be quite anticlimactic.

From the slides (since there's now way currently to actually see the live presentation), it would seem their ONLY focus is DX12. That really sucks. DX12 will only benefit the Windows Desktop platform and possibly Xbox One.

This leaves out:
1. Android
2. iOS
3. Linux desktop
4. Mac OSX desktop

They talk about Metal support, so Apple is covered. And it looks like Apple is going Metal exclusively, at least their logo is missing from recent Khronos Vulkan announcements. On the other hand Google/Android is supporting Vulkan, hopefully that will help.

So none of the big engine developers have made commitments to Vulkan so far - no CryEngine, Unreal or Unity 5. Worrisome. At the same time DX12 games will begin coming out this month (well there was technically one last month... sort off). At the same time Vulkan is not released yet. The more they take their sweet time, the more developers will get comfy with DirectX12. I wonder when do we reach the point of no return. Valve will really have to pull an ace from their sleeve or the Steam Machine premiere will be quite anticlimactic.

according to Tim Sweeney, Vulkan on UE4 is already in full swing of development

update: also, it would make no sense at all to go with DX12 and Vulkan at once being that they are similar. just looking at their slides you can see how deep they are in DX9 and old principles. the slide, DX12 running in 1 thread says everything. multithreading is same important to Vulkan too and without it... neither DX12 nor Vulkan can work efficiently


Last edited by vulture on 12 August 2015 at 4:29 pm UTC

For now, making their OpenGL better and putting effort into the Linux Editor is far more I could wish for. When Vulkan arrives, I am sure they will start working on it (maybe even before).

Yet another reason I wish more devs would look at Godot. They plan to have Vulkan support as quickly as possible. The day the world stops revolving around Unity3D will be a win for everyone.

So none of the big engine developers have made commitments to Vulkan so far - no CryEngine, Unreal or Unity 5. Worrisome. At the same time DX12 games will begin coming out this month (well there was technically one last month... sort off). At the same time Vulkan is not released yet. The more they take their sweet time, the more developers will get comfy with DirectX12. I wonder when do we reach the point of no return. Valve will really have to pull an ace from their sleeve or the Steam Machine premiere will be quite anticlimactic.

according to Tim Sweeney, Vulkan on UE4 is already in full swing of development

update: also, it would make no sense at all to go with DX12 and Vulkan at once being that they are similar. just looking at their slides you can see how deep they are in DX9 and old principles. the slide, DX12 running in 1 thread says everything. multithreading is same important to Vulkan too and without it... neither DX12 nor Vulkan can work efficiently

My concerns are not so much the "if" but the "when". It's the middle of August already. Honestly - look at all of the basic Windows gaming features that Linux still misses. I don't know about Nvidia users, but the Catalyst in Linux is a joke compared to Windows. There is no RadeonPro, no MSI Afterburner, no Nexus Mod Manager, no SweetFX/ReShade/ENB. The OS lacks an easy way to control the hardware through GUI. Also no SLI or Crossfire (not really). And finally, the performance is sub par. Even on Nvidia - check a Shadow of Mordor comparison. I'm not even going to talk about AMD - I have a 290x Crossfire setup so you can imagine my opinion includes a lot of bad words :).
So you have this this giant coagulated mass (and more) of problems and the Vulakn API is delayed. And there are three months for them to fix it before the Steam Machines roll out on November 10th. Obviously not going to happen. What will be Valve's pitch - "Get a sub par performance and less games and features now and we'll try to fix it later"? It's a train wreck in the making.