Why Open GL and Not DirectX should be the API of Choice for AAA Games

Gregster · 12 Oct 2013 at 13:28

OpenGL Vs DirectX is Perhaps One of the most underrated debates of all time. Many people dont even completely understand the difference between the two, i am sure some of you will be surprised to learn that you can get Games, with just as good graphics as DX on Open GL.

First of all let me say this: Open GL is basically an API called Open Graphics Library. You can think of an API as the basic pipeline through which your games are run. OpenGL and DirectX are basically the same thing except the fact that the latter is proprietary (Microsoft). Linux based systems and Mac OS based systems currently utilize Open GL while nearly all Windows Based systems utilize Direct X.
Thing is the world is moving towards an Open Source future, where literally everything is non-proprietary.
A common example is Android which is insanely popular since it is open source. Another very important fact is that Open GL is basically thought to be a more stable API than Direct X. Consider the following benchmarks of a GTX Titan Running Grid 2 (Direct X) and Rage (Open GL).

Notice how the GTX Titan has an absolutely rocksolid-stable FPS in Rage? You can thank Open GL (The AMD Bumps are because of Drivers) for that.
And you know what i am not the only one who thinks so:
Valve: OpenGL is faster than DirectX — even on Windows

”As for why OpenGL is faster than DirectX/Direct3D, the simple answer is that OpenGL seems to have a smoother, more efficient pipeline. At 303.4 fps, OpenGL is rendering a frame every 3.29 milliseconds; at 270.6 fps, DirectX is rendering a frame in 3.69 milliseconds. That 0.4 millisecond difference is down to how fast the DirectX pipeline can process and draw 3D data.” – ExtremeTech
The sad part is however that currently OpenGL is being utilized more by the Video Industry than Game Makers, Rage is one of the ONLY completely Open GL games around. Blizzard is another example, their games always are both Open GL AND Direct X based and tests revealed that they run FASTER on Open GL. Why? Because Open GL as a pipeline is simply better, that’s why.

A good read and I for one hope to see OpenGL used more by devs in the future. Is DX finished?

arc@css · 12 Oct 2013 at 13:31

I.D.Software is the only dev I'm aware of that use it. What others?

Martini1991 · 12 Oct 2013 at 13:32

I'd rather see OpenGL used over DirectX, that'd make Linux and Mac gaming a reality.

Gregster · 12 Oct 2013 at 13:32

arc@css said:
I.D.Software is the only dev I'm aware of that use it. What others?

Interested also and could do with some of Rroffs knowledge on this.

arc@css · 12 Oct 2013 at 13:33

Gregster said:
Interested also and could do with some of Rroffs knowledge on this.

Good to have you back btw, Gregster.

Gregster · 12 Oct 2013 at 13:35

arc@css said:
Good to have you back btw, Gregster.

Thanks Arcy

andybird123 · 12 Oct 2013 at 13:41

+1

From what i've seen of performance improvements on Linux, OpenGL is in the order of what they are talking with Mantle... devs supporting a single, truely open, cross OS api will benefit all gamers regardless of brand as well as making games easier to support for devs and drivers

LtMatt · 12 Oct 2013 at 13:49

Any link to the article Greg?

Whenever i think of Rage i think of this.

N19h7m4r3 · 12 Oct 2013 at 13:50

arc@css said:
I.D.Software is the only dev I'm aware of that use it. What others?

Every multi-platform game that uses the Unity engine uses OpenGL. There are more every day, and they're amazing.

Indies love OpenGL, as they can easily get multi/cross-platform games and gameplay.

http://www.gamasutra.com/blogs/Davi...Why_You_Should_Use_OpenGL_And_Not_DirectX.php

shankly1985 · 12 Oct 2013 at 14:05

Nvidia = OpenGL
AMD = Mantle

Would be the end of DirectX

But would removing DirectX out the game be a good thing?

N19h7m4r3 · 12 Oct 2013 at 14:11

shankly1985 said:
Nvidia = OpenGL
AMD = Mantle

Would be the end of DirectX

But would removing DirectX out the game be a good thing?

AMD has been increasing their OpenGL Support, especially on OS X for Apple, along with furthering their OpenCL lead.

Apple's new upcoming Mac Pro uses Dual AMD cards as standard to take advantage of those capabilities.
At the moment AMD is still lacking OpenGL 4.4 Conformance with the Khronos Group though.

LtMatt · 12 Oct 2013 at 14:12

I can't see DX being redundant all of a sudden. More choices is always a good thing though, especially if it improves performance. Its all if and buts at the moment though, need to wait and see some evidence, starting with Mantle.

Orangey · 12 Oct 2013 at 14:13

It's far easier to get started with DX. With OGL it's very daunting and fragmented, hard to figure out what you need, hard to find decent tutorials that are actually up to date, etc etc.

shankly1985 · 12 Oct 2013 at 14:17

This could work better for us more games using different API pick and choose witch is best for what platform you running.

Windows
SteamOS
Linux
MacOS

Microsoft would need to start stepping up there game and maybe stop forcing people to upgrade OS for a new DirectX, why Upgrade if Mantle or OpenGL does a better job?

But then again it could bring a end to Windows as a gaming platform, if so then good by DirectX.

teppic · 12 Oct 2013 at 14:27

shankly1985 said:
This could work better for us more games using different API pick and choose witch is best for what platform you running.

Windows
SteamOS
Linux
MacOS

The OS shouldn't matter. All of these support OpenGL, and games written with OpenGL can be ported between them easily. DirectX benefits only Microsoft, but the signs are that DirectX has no real future, and Microsoft has no interest in PC gaming.

shankly1985 · 12 Oct 2013 at 14:43

teppic said:
The OS shouldn't matter. All of these support OpenGL, and games written with OpenGL can be ported between them easily. DirectX benefits only Microsoft, but the signs are that DirectX has no real future, and Microsoft has no interest in PC gaming.

That is true... But just say every game from next year was OpenGL and Mantle, would people still go out and buy Windows 9 say

teppic · 12 Oct 2013 at 14:56

shankly1985 said:
That is true... But just say every game from next year was OpenGL and Mantle, would people still go out and buy Windows 9 say

That'd make Valve very happy. At the moment the DirectX drivers are better optimised in Windows, not surprisingly since almost all games use it. But if games began to switch to OpenGL (obviously Mantle with be optimised by AMD drivers) then you'd get no benefits in terms of features by upgrading from Windows 7 or 8 in those games.

Orangey · 12 Oct 2013 at 14:58

shankly1985 said:
That is true... But just say every game from next year was OpenGL and Mantle, would people still go out and buy Windows 9 say

It depends if/how MS react. These big changes don't happen in a vacuum, MS could entice people to stay on Windows somehow.

humbug · 12 Oct 2013 at 15:08

The Problem with OpenGL is not OpenGL, its that it can only run on Unix based systems, all of which are buggy and unstable, they seriously lack support.

Its saving grace maybe Steam. But, and there is a but. If Steam make a stable well supported OS then they may want to keep it lock to their pre-build "Steam Box"
Be that as it may, OpenGL PC gaming may become very expensive and locked.

If thats so then Mantle will be the choice for gamers, provided Nvidia chose to support it on their GPU's.

teppic · 12 Oct 2013 at 15:14

humbug said:
The Problem with OpenGL is not OpenGL, its that it can only run on Unix based systems, all of which are buggy and unstable, they seriously lack support.

Its saving grace maybe Steam. But, and there is a but. If Steam make a stable well supported OS then they may want to keep it lock to their pre-build "Steam Box"
Be that as it may, OpenGL PC gaming may become very expensive and locked.

If thats so then Mantle will be the choice for gamers, provided Nvidia chose to support it on their GPU's.

Eh? Unix systems are buggy and unstable? Think again...

OpenGL runs on anything, it's an open API.