Difference Between DX9 and OpenGl

[Levan]

I really want to know what is the difference between Open Gl and Direct X9 Renderer in PPSSPP??

I understand most of the platforms that PPSSPP is avilable on can not use DX9 but is there a difference between selecting one on windows version ??

Thank you in advance

[Bigpet]

Driver support on Windows can be really spotty, so some people have better performance with D3D and some with OpenGL. There also may still be some bugs that make things look different. Of course there's also various tools that hook into Direct3D or OpenGL.

Also, the postprocessing shaders aren't translated to hlsl, so you can't run them in D3D

[fivefeet8]

For AMD video cards, there is a nominal increase in performance switching to D3d.

[Levan]

(01-02-2015 03:06 PM)Bigpet Wrote:  Driver support on Windows can be really spotty, so some people have better performance with D3D and some with OpenGL. There also may still be some bugs that make things look different. Of course there's also various tools that hook into Direct3D or OpenGL.

Also, the postprocessing shaders aren't translated to hlsl, so you can't run them in D3D

So is it safe to say that openGl is being prioritized by developers ?? and it is getting more work done on it ?? Or is it both versions have something going for it ?

(01-02-2015 03:56 PM)fivefeet8 Wrote:  For AMD video cards, there is a nominal increase in performance switching to D3d.

Well interesting are they really that different ?? It is so interesting why did the dev team decided to make two different versions ?

[cybercjt]

Open GL is much more accurate on emulation.

D3D is just implemented recently so it's a bit buggy by now but from time to time it gets updates and later on it will be stable as Open GL. Also another good thing for D3D is it also supports low end / old gen GPU that doesn't support OP GL 2.0 above so good thing for those users who use PC with that kind of GPU .

[Bigpet]

For the longest time the OpenGL backend was the only renderer. The Direct3D one was only recently added because of some of the shitty OpenGL drivers on Windows.

The obvious reason is that OpenGL is available on all platforms whereas Direct3D is only available on Windows.

And the difference in performance shouldn't be big if people wrote decent drivers but AMD apparently does not want to or cannot spend those resources, so they decided to prioritize what most people use, Windows and D3D.

(01-02-2015 04:49 PM)cybercjt Wrote:  Also another good thing for D3D is it also supports low end / old gen GPU that doesn't support OP GL 2.0

... on Windows. Many of those devices have OpenGL 2.0 drivers on Linux, it's not always a hardware limitation, sometimes it's just software.

[Levan]

(01-02-2015 04:53 PM)Bigpet Wrote:  For the longest time the OpenGL backend was the only renderer. The Direct3D one was only recently added because of some of the shitty OpenGL drivers on Windows.

The obvious reason is that OpenGL is available on all platforms whereas Direct3D is only available on Windows.

And the difference in performance shouldn't be big if people wrote decent drivers but AMD apparently does not want to or cannot spend those resources, so they decided to prioritize what most people use, Windows and D3D.

(01-02-2015 04:49 PM)cybercjt Wrote:  Also another good thing for D3D is it also supports low end / old gen GPU that doesn't support OP GL 2.0

... on Windows. Many of those devices have OpenGL 2.0 drivers on Linux, it's not always a hardware limitation, sometimes it's just software.

Wow thank you and every one else who replied, you have been huge help

It is sad is not it that AMD has such pure support for every thing (even for windows drivers) On my linux pc I always stayed away from AMD hardware but now I think i will stay away from AMD even on my Windows pc Even though i feel their hardware is really good and wary well priced

[LunaMoo]

Actually on the performance topic, as an AMD user I just tested both in few games, without shaders since d3d doesn't have them and I would say OGL is usually a few times faster than d3d for me when very high res is used, so maybe other people just forgot to turn off shaders hence OGL was slower for them, or my gpu just has a lucky drivers(it's pretty old from hd5000 series, but still getting driver updates;3).

PPSSPP is pretty light anyway, so it doesn't really matter for me, but worth mention it's quite likely the first windows app using this backend which I don't have problems with. Not sure, if it's because drivers improved alot recently or simply ppsspp is much better coded than commercial products/games using OGL on windows which terrorized me in the past.;]

[Levan]

(01-02-2015 05:38 PM)LunaMoo Wrote:  Actually on the performance topic, as an AMD user I just tested both in few games, without shaders since d3d doesn't have them and I would say OGL is usually a few times faster than d3d for me when very high res is used, so maybe other people just forgot to turn off shaders hence OGL was slower for them, or my gpu just has a lucky drivers(it's pretty old from hd5000 series, but still getting driver updates;3).

PPSSPP is pretty light anyway, so it doesn't really matter for me, but worth mention it's quite likely the first windows app using this backend which I don't have problems with. Not sure, if it's because drivers improved alot recently or simply ppsspp is much better coded than commercial products/games using OGL on windows which terrorized me in the past.;]

This might be because I am mostly a linux user and I might be bashing AMD because of it too much but nvidia GeForce 8 Series from 2006 are still getting updates and on linux they are good drivers and AMD driver support is just horrendous on linux.
Any way thank you for the information .

[LunaMoo]

If I ever sound in this forum like a fanboy, it's certainly about ppsspp<3 and not any big corporation/hardware manufacturer/brand, so as for me, anyone can bash any of them as much as they like. I just shared my personal experience since it was different.:3

Older pre dx11 amd gpu's doesn't get driver updates for windows either, so yeah, not everyone is in the same situation:3.

[Accel]

My laptop (see sig) is quite good enough to play game at full speed with opengl backend and some speed boost option turned on
except for Resistance: Retribution, that game lag like hell. God of War games run better than it

[GuilhermeGS2]

My GTX 650 works better on OpenGL, on D3D the performance is limited, but I didn't test much the D3D. Anyway on OpenGL I can run GoW in 60 fps with FXAA and all texture filters in full screen, I have some FPS drops because my processor is poor (Celeron Dual Core E3300).