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DalTXColtsFan
01-17-2004, 03:43 PM
Hello all,

I was hoping to get some tips for a demo/tutorial I'm going to start working on soon.

On my site http:\\daltxcoltsfan.tripod.com the second demo down is a modeling tool I've been working on. The site isn't up to date but it at least shows the idea.

What I plan to do is a series of examples that hopefully cover a significant portion of what can and can't be covered by default OpenGL lighting. The only meaningful examples I've come up with so far are:

Directional lights
spotlights hitting glu spheres and cylinders
spotlights hitting polygons, to demonstrate that light calculations happen at the vertices so if you shine a spotlight at the middle of a big rectangle nothing happens,
color mixing between lights and polygons

and that's really it - what I'd like to illustrate are meaningful things you can do with the combination of material properties and lights, like specular reflection and shininess, and also when will turning on and off Local Viewer and Separate Specular Color actually give different results, but I'm having trouble getting any of them to work.

So what I'm hoping for is suggestions for other meaningful combinations of light and material properties for the tutorial/demo.

Any thoughts? I'll appreciate them!

JanHH
01-18-2004, 02:49 PM
Why do you want to do so? the red book covers all kinds of standard OpenGL lightings available with lots of examples how different material properties affect the visual result, and also, standard OpenGL lighting is not used very much nowadays anyway, it's pretty outdated, so who would be interested?

Jan

DalTXColtsFan
01-19-2004, 09:56 AM
I read the chapter in the redbook again and you're right, there were several good examples in there. I hadn't read it in awhile because I'd been having so much fun on the NeHe forum!

My intention with the tutorial is simply to demonstrate as throughly as possible exactly what standard OpenGL lighting and materials can and cannot do. That's all. Target audience? Beginners - period. Just a way they could quickly look on the net and see examples of what you can do without having to use dynamic lightmapping or per-pixel lighting (not that they're bad, just providing information on the strengths and shortcomings of what you "get for free".)

It appears that I may have overestimated what standard lighting can do - I mean

directional lights
vertex-calculated spotlights
color combining
specular reflection higlights with varied "focus of shininess"
varied attenuation

above and beyond this, is there really any other benefit you get without having to resort to lightmaps or the other stuff I mentioned above?

I probably should have waited until I actually finished the first few chapters of the demo before posting this, but if anyone can see any big benefits that I didn't list I'd love to hear it.

Thanks
Joe