Direct X or Open GL

[Ian_Coleman]

I have always run TRS2004 under Open GL, and I have never had any problems.
This morning, when I tried to reload a session that I had been working on, it came up with a screen telling me there had been a fatal exception.

I tried reloading, but the same thing happened again.

So I went to the Trainz configuration screen and changed from GL to Direct X, and then I reloaded the session and it ran perfectly.

I have never had this situation arise before, and it got me wondering -

What would normally govern the decision as to which one to use?

Ian

 

[Smileyman]

There are many reasons really.

I've found that OpenGL support on ATI cards is a joke, so always run DirectX on those (if I have to run ATI that is :hehe.

On Nvidia cards, both seem to run pretty well, although if you use old drivers on an NVidia card, OpenGL will usually show garbled graphics or give you a blue screen error.

I remember a few years ago that one of them used to run TRS2004 better than the other, but with the latest drivers it doesn't seem to be the case any more.

I can't imagine why you'd get an error suddenly from OpenGL with a session, and then have the session work in DirectX.
Have you installed any new content lately?
Maybe there's a piece of content that's tripping up OpenGL, that DirectX is dealing with.

Smiley.

 

[Ian_Coleman]

Thanks for your reply Smiley.

I do have an ATI card, and until today, had never used direct X.
There is no downloaded content in the layout.
Ian

 

[johnwhelan]

Thanks for your reply Smiley.

I do have an ATI card, and until today, had never used direct X.
There is no downloaded content in the layout.
Ian

DirectX is optimised for sims and games under Windows. OpenGL has many historical methods of doing things which has made it less than ideal for Windows and games. ATI went for the DirectX side of things so in general ATI cards run better in DirectX, nVidia tranditionally has been more OpenGL. Both companies now have reasonable drivers for DirectX and OpenGL.

Cheerio John

 

[NYCboy]

so is this basically saying ATI will work better with next next-gen games.

 

[johnwhelan]

so is this basically saying ATI will work better with next next-gen games.

No in fact nVidia is probably a better bet they have recently introduced CUDA which allows you to use the GPU for conventional processing, providing it is programmed using CUDA.

Having said that I think a researcher in Israel has been running CUDA code on ATI video cards.

Cheerio John

 

[BLueNeon]

No in fact nVidia is probably a better bet they have recently introduced CUBA
Cheerio John

Actually nVidia recently introduced CUDA , and despite nVidia's marketing blurb , uptake by Devs has been slow , and fixes and updates by nVidia even slower :hehe:

 

[johnwhelan]

Going to the nVidia site I agree it should be CUDA I happen to look at a different site.

http://www.google.ca/url?sa=t&sourc...L56r_OStWY8xVo04A&sig2=F004v8Uyc_M6UN9ag5dt7Q

This stuff is very new and it takes a couple of years to write a game but there are some applications that are already using it.

Larabee is the other interesting one apparently it can run 86 code on the gpu.

Cheerio John

 

[BLueNeon]

Going to the nVidia site I agree it should be CUDA I happen to look at a different site.

http://www.google.ca/url?sa=t&sourc...L56r_OStWY8xVo04A&sig2=F004v8Uyc_M6UN9ag5dt7Q

This stuff is very new and it takes a couple of years to write a game but there are some applications that are already using it.

Larabee is the other interesting one apparently it can run 86 code on the gpu.

Cheerio John

Hi

I was thinking more of game devs , who have indeed been slow to use CUDA , not surprising when you consider the potentional to lose a good portion of your sales if CUDA was fully utilized ... As for Intel , they took some of the best and brightest > Michael Abrash and John Carmack on board for Larabee , I'll bet the Red and Green teams are worried .Definiatley 2 titles to come on release of Larabee ... looking forward to it .

Not sure if you have seen this other Intel funded project that has the potentional to change everything for the consumer if/when .. Lucid Hydra http://www.lucidlogix.com/technology/index.html

Cheers

 

[duncanw]

For my 2 bobs worth - had a little fiddle in TRS2006 this morning between DirectX and OpenGL (beofre I found this thread) and DirectX appears to draw water with some realism whereas in OpenGL water is nothing short of pathetic. I'm running a new Asus laptop with 4gb RAM, Vista Ultimate and ATI Radeon HD3650 graphics with 512mb VRAM.

Cheers

Duncan

 

[tads1]

Hi,about 2 years ago (old forums)I posted a thread directX vs OpenGL,with the camera in exactly the same spot ran in both DX and openGL,all benchmarks ran,DX came out on top way ahead of openGL for frame rate,some were as much as 20 fps more in DX,than what GL could render,DX is more native to the card than what GL is.I always play in DX.

 

[johnwhelan]

Hi,about 2 years ago (old forums)I posted a thread directX vs OpenGL,with the camera in exactly the same spot ran in both DX and openGL,all benchmarks ran,DX came out on top way ahead of openGL for frame rate,some were as much as 20 fps more in DX,than what GL could render,DX is more native to the card than what GL is.I always play in DX.

But it does depend on the card. Some are better at Directx some are better at openGL.

Cheerio John

 

[tads1]

But it does depend on the card. Some are better at Directx some are better at openGL.

Cheerio John

Yes I would agree with you John,Iv'e only used Nvidia cards for the last 10 years or so,Never had the pleasure of running an ATI card,my bro had one and it was good from what I seen running.It could be time for a change

Daz

 

[Iced8383]

I highly recommend Direct X. It just seems to be better...