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Dakusan

OpenGL Opengl & Direct3D

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Well, my world was rocked today. I stated using DX about a year ago and have always been happy with everything about it, it was very robust, speedy, documented, had options and functions out the ass, was very consistent in the ways it did things, heck, I had no complaints whatsoever. Until recently that is, I decided to make a dynamic mid point fractal generator so you could walk through an infinite 3d world, dynamic lighting and shadows, bla bla bla, I used a quad tree implementation originally, when I realized I could make a ray traced implementation that would speed things up 20 fold, only problem, DX didnt seem to support reading the z or stencil buffer, and I had read ogl did, so great. I quickly rewrite the engine into OGL using vertex lists instead of vertex buffers, and everything, and low and behold, it ran twice as slow but kept a more consistent frame rate, so from what I can see, DX may be faster now than OGL, is it just me? Not only that, but ogl has horrible documentation it seems, and isn't very consistent in its functions and names it uses it seems to me. Please prove me wrong on that point, I'd love a good list of the functions and arguments for each one and types and all, like the MSDN and their help files have. All Opengl originally had was the speed and cross platform aspect, but without either of those, it might as well be dead... I'm not trying to start a flame war or anything as I'm sure these boards have seen more than enough of, but... WTF, ive been told of OGLs speed over D3D since i first heard of a voodoo way back when. [edited by - Dakusan on July 27, 2003 12:15:58 AM]

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quote:
Original post by Dakusan
[...stuff...] is it just me? [...stuff...]


Yes.

Next time try to first understand an API, before making claims about its performance. Ever considered the possibility that it might be your code ? OpenGL vertex array and Direct3D vertex buffer performance is exactly the same, because they access the exact same GPU functionality. What a surprise.

For OpenGL documentation, look for the Redbook, Bluebook, and the official OpenGL specifications.

Obvious flamebait. Closed.

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Hate to reopen this (temporarily) but since I have already written a response...
quote:
Original post by Dakusan
I quickly rewrite the engine into OGL using vertex lists instead of vertex buffers, and everything, and low and behold, it ran twice as slow but kept a more consistent frame rate, so from what I can see, DX may be faster now than OGL, is it just me?
It's just you. Seriously, well-written OpenGL code will almost always be the about same speed as well-written DirectX code.
quote:
Original post by Dakusan
Not only that, but ogl has horrible documentation it seems, and isn't very consistent in its functions and names it uses it seems to me.
The names and functions seem pretty consistent to me. Which ones do you have a problem with?

As for documentation, there's the spec (found on OpenGL.org), numerous books, the extensions registry, tons of whitepapers and other articles on NVIDIA's and ATI's websites. Not to mention the fact that MSDN contains extensive documentation of OpenGL as well.

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