Whats the difference between OpenGL & DirectX ?

[shawnwulff]

Whats the difference between OpenGL & DirectX ?

Whenever I run trainz 2009 in OpenGL it crashes. When I run it in DirectX it runs fine? What is the difference between the to?

 

[SuperFudd]

I'd like that answered.
I know one is from Microsoft and one is not.

 

[johnwhelan]

Whats the difference between OpenGL & DirectX ?

Whenever I run trainz 2009 in OpenGL it crashes. When I run it in DirectX it runs fine? What is the difference between the to?

OpenGL is an open standard for graphics on many operating systems. Unfortunately it takes about five years for something to get through the standards process so they allow extensions by manufacturers. This means it is no longer a standard but could even be considered propitiatory. ie you can only use nVidia graphics cards to run this program.

Because it includes a lot of older out dated requirements OpenGL 3.0 is practically dead for game performance on windows, there was a write up about this in tomshardware.com

DirectX was created by Microsoft by looking at the requirements for games on Windows computers in consultation with graphic card manufacturers. ATI actually coded their graphics cards so they ran DirectX instructions in hardware giving much better price performance than nVidia. These days I think nVidia also has much of the directX instruction set in hardware. Basically it was created specifically for Windows games etc. OpenGL has its roots in CAD programs on Unix.

Most game engines are looking at Directx 11 rather than 10. 10 doesn't give much improvement over 9 and there are a lot of 9 cards out there.

Basically why does one work and the other not, it comes down to the quality of the drivers.

Cheerio John

 

[shawnwulff]

Thanks John. It makes sense know.