In the interview i watched where he was showing idtech5 off, im pretty sure he said something like "this is all running on openGL, so no need for DirectX 10"

i could be wrong, or maybe this is dated info?

Quote: Original post by Interesting Dave
In the interview i watched where he was showing idtech5 off, im pretty sure he said something like "this is all running on openGL, so no need for DirectX 10"

You are correct. And even the big studios using DX10 haven't all been wild about it - remember when it was discovered that you could enable the DX10-level graphics in Crysis under DX9?

Quote: Original post by TheGilb
You'll have to wait for OpenGL3 to get finished before you can match the capabilities of DX10 but in all honesty both DX9 and GL2.1 offer the same capabilities it's just a different interface.

I'm pro-GL but let's just say I heard Carmack said they'd be using DX for the idTech5 engine.. Bring on GL3 .. soon!!!

When GL3 is finished it'll be the only API to support the same capabilities as DX10 on windows xp, and other compatible platforms.

It runs on OS X. That should be a strong indicator of doing the job in opengl. If it supports DX That is a plus for MS. It was demoed at one of the recent mac expos so there should be video of it running on a mac out there.

So OpenGL does not have file loading and sound capabilties. How can you overset this? Through extensions?

Quote:
You are correct. And even the big studios using DX10 haven't all been wild about it - remember when it was discovered that you could enable the DX10-level graphics in Crysis under DX9?

All that really means is that Crysis didn't take advantage of the features of D3D10 that require hardware support (e.g., geometry shaders) or could intelligently fall back to the code path that did not use geometry shaders when they were not present even though you were running the game "Direct3D 10" mode. I'd be extremely skeptical of any conclusions drawn based on the "Crysis argument," since the unlock was originally discovered by gamers (traditionally rather technically inept) and game developers traditionally play fast-and-loose with customer-facing tech usages (because its the path of least resistance). Without seeing the code and knowing what Crysis is actually doing under the hood, it's dangerous to make too many conclusions.

A lot of what Direct3D 10 offers as a benefit to developers is not fancy stuff like the geometry shader, it's the reorganization of the API and its underlying semantics to make it cleaner and to allow more work to be done kernel side and for better GPU resource virtualization. As an aside, this doesn't map 1:1 to OpenGL because OpenGL never had the same semantics as Direct3D 9, entirely, so some features don't translate exactly.

Developers are more likely to be less-enthused with Direct3D 10 because it's such a breaking change (while ultimately for the best, this does make it neccessary to have multiple code paths for the renderer to support 9 and 10) that also requires investment from the userbase (that is, Vista and a D3D10 card), so that switching wholesale to D3D10 is not a good business move. But then again, many of us have to / have had to scale all the way back to fixed function support, so...

Quote:
I was thinking of OpenGL, however compared to Direct3D, it does not look that great, or am I mistaking? I also looked at Microsoft's XNA, but for some reason it gives me the creeps, maybe it's beacause of the proprietary code.

OpenGL's code is proprietary too, you know. There are open-source implementations floating around (like Mesa), but the OpenGL that drives your fancy games is completely closed.

OpenGL's probably what you want to try first if you are more comfortable with the C programming paradigms.

Quote:
So OpenGL does not have file loading and sound capabilties. How can you overset this? Through extensions?

No. You need additional libraries for this. OpenGL should be compared to Direct3D, not DirectX, which is a suite of libraries.

OpenGL and Direct3D are basically functionally equivalent. Your concerns about the appearance of games you've played almost assuredly come down to art content, which can easily make-or-break the visual experience for a game.

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There is certainly no plans for a commercially supported linux version of Rage, but there will very likely be a linux executable made available. It isn't running at the moment, but we have had it compiled in the past. Running on additional platforms usually provides some code quality advantages, and it really only takes one interested programmer to make it happen.

The PC version is still OpenGL, but it is possible that could change before release. The actual API code is not very large, and the vertex / fragment code can be easily translated between cg/hlsl/glsl as necessary. I am going to at least consider OpenGL 3.0 as a target, if Nvidia, ATI, and Intel all have decent support. There really won't be any performance difference between GL 2.0 / GL 3.0 / D3D, so the api decision will be based on secondary factors, of which inertia is one.

John Carmack

from http://games.slashdot.org/comments.pl?sid=302231&cid=20671657
Posted in September last year i think.

The officially supported platforms will probably be MacOSX, Windows, PS3 and Xbox360 from what i've read.

The only API i would avoid for a game that is about to be released would be D3D10 due to the "low" (around 13% in february 2008 according to net applications) marketshare of Windows Vista. Windows in general has around 92% marketshare according to the same source, GNU/Linux is at around 0.6%(About the same as Windows98) and MacOS(All versions) at around 7.5% (It isn't accurate numbers though since its based on browser id strings gathered from certain websites but it should give you a rough idea on what OS you really really want to support)

(Vista's marketshare appear to be growing quite rapidly though so in a few years it will probably be safe to ignore XP for non-casual games)

Ok, so do you have any recomandations of some DirectInput similar lib's to use in conjunction with OpenGL, or some sound libs, or even some netcode libs?

SDL provides sound, input and networking.

Quote: Original post by Tegramon
Ok, so do you have any recomandations of some DirectInput similar lib's to use in conjunction with OpenGL, or some sound libs, or even some netcode libs?

SDL and SDL_Net works well for sound , input and networking if you're aiming for platform independance.

OpenAL is also a nice multi platform option for sound (Its even used with alot of DirectX/Windows titles such as Battlefield 2, Bioshock and many others).

OpenAL platform support works out like this

Quote:
Platform Devices Licence Holder
MacOS 8/9 Sound Manager Open Source (LGPL)
MacOS X Core Audio Open Source (Apple)
Linux OSS Open Source (LGPL)
Linux ALSA Open Source (LGPL)
BSD native Open Source (LGPL)
Solaris native Open Source (LGPL)
IRIX native Open Source (LGPL)
Windows MMSYSTEM Open Source (LGPL)
--------DirectSound Open Source (LGPL)
--------DirectSound3D Open Source (LGPL)
--------NVIDIA nForce Open Source (LGPL)
--------Creative Audigy Creative Labs Inc.
--------Creative Audigy 2 Creative Labs Inc.
--------Creative Audigy 4 Creative Labs Inc.
--------Creative X-Fi Creative Labs Inc.
Ms Xbox native Creative Labs Inc.
Ms Xbox 360 native Creative Labs Inc.

For a Windows Only title you could use plain Winsock for networking and the Windows API for input aswell.

Thanks for all the help. I chose to remain on a combination of OpenGL and SDL for now since they are free and seem to be pretty good for a low budget 3D app.