direct X / Open GL ?

dzien50

New member
Hi
What is the difference between these two, in fact I don't even know what they are or what they do ? and how do they affect trainz ?

Cheers
PJ
 
Hi PJ,

DirectX and OpenGL are pieces of software that are used by graphics cards to make the display that you see on your screen. Most graphics cards will support either and OpenGL is considered to give better results. That said DirectX seems to perform better with 'older' or low end systems. Its worth changing between the on your machine to see which works best

Andy
 
Hi
What is the difference between these two, in fact I don't even know what they are or what they do ? and how do they affect trainz ?

Cheers
PJ

OpenGL is a "Conventional" standards based standard, DirectX is a "standard" defined by Microsoft specifically for games.

So it takes about five years for something new to enter the formal standard for OpenGL and five minutes for something new to enter the DirectX standard. OpenGL has its origins in CAD programs and thus carries a fair amount of historical baggage.

However life is never simple so in order to allow companies to use features that are more relevant today the OpenGL standard allows companies to add extensions. nVidia has added a lot of extensions. nVidia also provides a lot of support to games companies such as Auran on how to get the best performance out of their cards so Auran are using nVidia code for example in the new texture compression of TRS2009.

In general you get better performance using DirectX but it does depend on the individual graphics card, motherboard and driver combination.

Cheerio John
 
OpenGL is a "Conventional" standards based standard, DirectX is a "standard" defined by Microsoft specifically for games.

So it takes about five years for something new to enter the formal standard for OpenGL and five minutes for something new to enter the DirectX standard. OpenGL has its origins in CAD programs and thus carries a fair amount of historical baggage.

However life is never simple so in order to allow companies to use features that are more relevant today the OpenGL standard allows companies to add extensions. nVidia has added a lot of extensions. nVidia also provides a lot of support to games companies such as Auran on how to get the best performance out of their cards so Auran are using nVidia code for example in the new texture compression of TRS2009.

In general you get better performance using DirectX but it does depend on the individual graphics card, motherboard and driver combination.

Cheerio John

John,

So, if my computer's video card is using nVidia, I should be using DirectX ?
 
I have a nVidia card and oddly enough find that on the same machine TRS04 is significantly better running in DirectX while TRS06 is better with GL. Experiment with the settings on your machine, you won't break anything ;)
 
John,

So, if my computer's video card is using nVidia, I should be using DirectX ?

The early nVidia cards and driver combination worked better with OpenGL but nVidia's drivers matured and you may find that DirectX performance is better, which has not always been the case.

Also different versions of Trainz may work better in one or the other.

Cheerio John
 
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