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dpoon
08-08-2009, 09:40 PM
After a long stint on XNA and Direct3D I've recently come back to OpenGL. Whilst reading the specs and docs to come up to speed on the latest version of OpenGL I ended up writing a basic OpenGL 3.1 (forward compatible 3.0) app to help with my learning. Anyway I'm releasing the code in the hopes that other developers in a similar situation might find it useful.

http://www.dhpoware.com/demos/gl3HelloWorld.html

kingc8
08-10-2009, 01:35 PM
That's great, thanks very much for your contribution, I'm sure it will help quite a few people get started with the forward compatible OpenGL 3.x series.

However I want to make some comments regarding it.

Having read Mark Kilgard's recent comments on deprecation, I have to agree somewhat with him that at this stage deprecation could possibly increase your hacking time a little...

I did an sloccount on your code to determine the total amount of effort required to initialise a context, set up a quad and texture it with a png.

Total Physical Source Lines of Code (SLOC) = 5,607
Schedule Estimate, Years (Months) = 0.58 (6.94(Months!))
Est'd Avg # of devs (Effort/Schedule) = 2.11
Total Estimated Cost to Develop = $ 165,123

Yeah yeah, it's good fun to play with sloccount.. but still, 5607 lines of code.

To put this in perspective, I wrote an OpenGL API 1.1 wrapper header that does complete 2D ortho texture and quad management with png decoding built-in to the header itself and when I sloccounted it, it came to 2,376 lines of code for the whole thing. -Less than half the size of this example.

I'm guessing the 3 series is at an early stage where wrangling utilities/headers haven't been developed yet. Because the boiler-plate 3.x code seems to be fairly verbose.

And finally from the code:

// OpenGL 3.0 also deprecates fixed-function vertex processing. This means

// that we also need to calculate the projection, view, and model matrices

// by ourself.

Oh.. /Reads book on calculating projection, view and model matrices. (sigh) :-)

Stuart McDonald
08-11-2009, 12:54 AM
Nice example. I really like the stuff on your site.


but still, 5607 lines of code.Did you look at the code? There's almost 3000 lines of (probably auto-gen'ed) code for getting function pointers. Plus code for mouse etc.