Opengl Platform Independence (PC/MAC) question

Hello All;
I registered earlier today and just now tried to log in 3 times and it seemed to work but the system still says I'm not logged in - I do not know why.

I am a Educational Simulation software designer and not a developer so I have a very basic technical question about Open-Gl. I'm pretty sure I know the answer but would like to hear it from the experts and would like further clarification.

Currently, we have developed immersive and interactive simulations exclusively for the PC platform using such higher level toolkits like Vega (Multigen-Paradigm), Worldtoolkit (Sense-8), and VTREE (CG2). However, folks have often complained that we don't develop for the MAC platform too. Previously, I thought that you would have to develop two applications separately which would be cost prohibitive for us.

However, I have recently found out that if we have a developer use Open-gl (Rather than a platform-specific toolkit), then we may be able to develop for both platforms (PC/MAC) but develop only one set of code.

I have come to this forum to find out if this is in fact true. Can one or several of ya let me know if Open-gl would let us develop one set of code but use it for both MAC and PC ?

Is this what most folks do in order to develop for several different platforms ?

Thanks for any enlightenment you can provide me.

Tim

[MikeC]

Yes, absolutely. This is one of the major reasons why many people prefer OGL to D3D. There will still be minor differences between platforms, mostly in the binding between the GL and the windowing system, but the vast majority of GL code is fully portable. Even the binding differences can be hidden away if you use a cross-platform toolkit such as SDL, which abstracts these things along with input, sound and the like.

Of course, there's a lot more to any real app than just OpenGL calls. Depending on your app and dev language, you may need other cross-platform toolkits for GUI and so on.

[MikeC]

P.S. re the login problems - do you maybe have your browser set to block cookies?

[mikael_aronsson]

Hi !

If just need OpenGL and no fancy gui stuff you could use glut or any of the other platform independent libraries to hide the OS specifiec stuff (creating windows and so on).

Mikael

[Tim Dedula]

Hello All;
Thank you MikeC and Mikael for your helpful responses. I am very familiar with platform-specific toolkits such as Vega, Worldtoolkit, and CG2 but I didn't realize that platform-independent toolkits existed. I am very interested in learning more about them.

Could someone lead me to some "easy-to-understand for a non-programmer" resources for SDL or for other popular cross-platform toolkits ?

Are there any web sites out there for products or resources that directly addresses the process for developing graphics and simulations for PC and MAC ?

[MikeC]

Well, the SDL homepage is at http://www.libsdl.org/index.php - there are various docs on there, although obviously most if not all of them will be geared toward developers.

For higher-level stuff, you're probably better off posting a question on the "OpenGL Toolkits" forum on this board. I think some developers of various toolkits post there, though, so be prepared for the possibility of conflicting advice ;-)

[MikeC]

I would steer clear of GLUT for serious apps, though - it was designed as a learning framework, and is great for that, but is very limited compared to other toolkits out there.

[ToolTech]

Why don't you take a look at the Gizmo3D toolkit. It is platform independant. Can be used with e.g. Qt to get 100% platform indep integration and has a very good performance.

www.gizmosdk.com (http://www.gizmosdk.com)

[Tim Dedula]

Hello ToolTech, etc ...;
Gizmo3D looks good but I see you have to deal with run-time licenses. We require a way to develop cross-platform (PC and Mac) where we can distribute an application to an unlimited number of users without licensing requirements.

Any "really-Good" Vis-Sim tools out there that meets these requirements ?

Tim

[ToolTech]

Gizmo3D is commersial. However we have a select license model that alows a customer to distribute to any numbers of customers.

We have node locked licenses , server (shared) licenses, evaluation licenses and non commercial free licenses...

[nigels]

A very good cross-platform toolkit is Qt (http://www.trolltech.com) .
It is oriented to C++ GUI applications and includes OpenGL support. Qt is multi-platform, including MacOS.

On the topic of MacOS, we could use some help with getting OpenGLUT (http://www.openglut.org) ported beyond X11 and Win32. ;)

Cheers,

Nigel