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Chocoboko

OpenGL OpenGL on a slow computer

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Chocoboko    124
I was testing out the Zelda demoes from NeHe''s group. They run incredibly slow for me. I''m running a Pentium 200 mhz and this computer was made in 1997. But I figure that 2D OpenGL should run fine for me because I am using Borland C++ 4.52 which was made in 1994 and it had libraries for OpenGL with it. Can someone tell me which things are likely to cause slowdowns in OpenGL on a slow computer? Thank you.

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SuperSlow    122
well for an old school game like that, it may well be the video card if you''re running it on a high resolution. Other than that, remember that the game is being interpreted. So processing speed is key.

I don''t think it''s so much OpenGL that''s slow.

2001 Bright Rally Red Camaro SS
2002 AMD Athlon XP 1800+ Thunderbird

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Natix    122
quote:
Other than that, remember that the game is being interpreted. So processing speed is key.


The zelda Chocoboko is talking about here is not an emulated version, but a full remake of the game (c++), so if the game is slow, it''s because of OpenGL. Unless the game is poorly coded...

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DannerGL    122
quote:
Original post by Chocoboko
But I figure that 2D OpenGL should run fine for me because I am using Borland C++ 4.52 which was made in 1994 and it had libraries for OpenGL with it.

It doesn't matter that the game is using "2D OpenGL" It still probably through much the 3D parts of the OpenGL pipeline. It definately has to go through many of the rasterization parts which is the slowest (most computationally expensive) part of the pipeline).

Although it may be easy to write a 2D game using OpenGL (and you can get some cool 3D effects with it), it's not neccessarily as fast as using a 2D only API (like DDraw or GDI etc.). It will only be fast enough if you've got the Graphics hardware muscle to support OpenGL.


[edited by - DannerGL on October 1, 2002 9:48:04 AM]

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browny    139
Consider upgrading ur graphics card....

I have a distinct feeling that your card doesn''t have any hardware acceleration. Without HAL, OpenGL can be a big pain in eyes.

My computer is a PII ( 350 MHZ ) and it had a pesky Sis AGP Card few months back. Doing anything in OpenGL back then was a sheer pain in ass and eyes both. But now i own a TNT2 nVidia 32 mb card ( not a very hi-fi one, but still good enough for the job ) and OpenGL performance has been mind bogling ever since.

OGL is cool !

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chris_graham    122
Doing simple 2D blitting using the windows software OpenGL driver yields a fraction of the speed as using Allegro (i.e. DirectDraw) to do it. I suppose this must be due to that software driver being really lame because I doubt simply doing a pixel transfer can have much 3D overhead!

[edited by - chris_graham on October 3, 2002 9:45:48 AM]

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