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Vilem Otte

OpenGL OpenGL and DirectX10

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Hi everyone, I've got a game engine build in C++, but it's not the question - the question is: It's rendering using OpenGL and my OtteRT(realtime raytracing), I'm thinking about to support OpenGL/Direct3D10 + OtteRT, what do you think about that? I know, that it is possible, but has it any reason to support both api's?

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Not really worth the trouble, IMO. Depends on what you need. OpenGL is cross-platform, but Direct3D10 is more advanced and has more features.

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I'd say stick with OpenGL unless you want to make full use of directX. Using cross platform API's like OpenGL should make your program portable to linux and macs with out to much trouble which will make all those microsoft haters happy as your not forcing them to boot into windows to use your software.

Support for both is really unnecessary if it's going to require windows to play maybe you should of started with directX or XNA for vista but since you've already started in OpenGL adding support for Direct3D is going to take a lot of time wth out that much gain.

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Quote:
Original post by Sc4Freak
Not really worth the trouble, IMO. Depends on what you need. OpenGL is cross-platform, but Direct3D10 is more advanced and has more features.


Wow, so not true. OpenGL can use all D3D10 features in XP, where as D3D10 is Vista only. It's called extensions. It's a bit more of a pain but opens SOOOOO many more doors. Especially if you're already familiar with OpenGL, stick with it. Depending on how you write your engine you can make the OpenGL features just as easy to access also.

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Quote:
Original post by Mike2343
Wow, so not true. OpenGL can use all D3D10 features in XP,

Not entirely true. The currently available OpenGL versions can use most D3D10 features on XP, but not all, and only on NVidia. This will be different with the upcoming 'Mount Evans', but we're not there yet. Then again, D3D10 won't run at all under XP, so you don't have much choice there.

Anyway, supporting multiple APIs in an engine is a waste of time. Select one and stick with it. Later on, start a new project using the other API. Then you know both.

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Thank you,
i'm gonna to use my own realtime raytracing api, but not now - in 3 maybe 2 years (Everyone hasn't got Quad core CPU at 4 GHz now), this time i'll release my game engine with OpenGL (probably, i don't wanna to write a direct3D port - it would take two years and then realtime raytracing - it's quite stupid). I've got OpenGL rendering (well it uses a little raytracing) completed, but D3D10 - i haven't got any line in my engine of DirectX. I'm gonna support Mount Evans (when it comes), but today it'll be just Me and OpenGL 2.0 (Ati Radeon HD or X series doesn't support OpenGL 2.1 (I know it, i've got Radeon HD 2900 XT - well it's very good, but no geometry shaders right now - i'll wait few weeks to new drivers)

for Mike2343 - I'm familiar with both apis (OpenGL/DirectX)

Well, i'm gonna complete it in few months (i've got so called "alpha version" at home, but it isn't at so good performance and still has some big bugs).

By the way - it is engine with just editors, no writing of source code - just few editors - you'll play and create a game/demo/.... (anything). I'm gonna supporting few game types (RPG - this is, why i create it - it'll be engine of my project, FPS - standart First Person Shooter and thinking about RTS - strategies are difficult, and i like "difficult work")

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