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OpenGL OpenGL- program to best performance

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dark_stalker    122
I am starting my first full 3-d game, and I have a few questions about performance.. if there is anything else that you have to say, any tips, they are welcome! By the way, I''m programming in regular C, and I''m making a full 3-d (1st person) RPG. I''d like to get the performance to the max! 1. Primitives- should I stick to mostly ALL triangles, or should I use some squares? 2. DirectX- I know I''ll be using everything except for DirectPlay, (maybe to set screen res) but does it work good when combined with OpenGL? In what situations should I use DirectX over OpenGL? I''ve seen demos at a programming site where one is just plain OpenGL, and another is OpenGL and DirectX combined- why is the second one so fast? (almost 3x the fps) Generally, how and where can I use DirectX to speed up OpenGL? (I''ll review my books, just incase I missed something) 3. GLUT- I''ve heard it''s slow.. So I should stick away from GLUT? 4. Windows programming w/OpenGL- Would it be worth it to learn some windows? (I want to make a real-time 3-d RPG.) 5. Software- Are 3D Studio Max, Maya, Granny, etc, worth the money? Is it really THAT hard (upwards of $350-$600) to animate your characters and make maps? 6. Any other things I should know about performance? Thank you for your time!

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benjamin bunny    838
1: Use triangle strips and fans wherever possible, and vertex buffers.

2: openGL can''t be combined with DDraw or D3D, so I''m assuming you mean the demo used Dinput or something, but this won''t make any difference to performance.

If you want to know what 3D api to use, try them both and see which one you prefer.

3: GLUT''s fast and easy, and its a good place to start if you''re learning openGL and don''t want to be bogged down with the win32 api, but you''ll have difficulty running anything fullscreen.

4: yes

5: you try making a character just entering numbers into notePad

Generally speaking you get what you pay for - with the exception of truespace 4; it''s got LOTS of bugs.

6: if you''re going for a claustrophobic (quake like) environment, use BSP trees. Otherwise use lots of fog. LOD techniques are worth investigating if you''re rendering landscapes.

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zedzeek    529
mate if its your first program DONT worry about performance, take the advice of all the experts NONE will say performance is important 4 a first project. what is important is to get whatever u wanna do working. its a typical begginners error to worry about performance i know i was guilty of it. ok in case its still not clear
performance == BAD
working program == GOOD

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