Archived

This topic is now archived and is closed to further replies.

This topic is 5629 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

Well, first hello everybody, I am starting my first attempt on a 3D Engine. I´ve coded everything from perspective projection to solid shading, so that I could have a better understanding of all the 3D stuff. I am at a point that I can draw a wireframed object loaded from an X file. The next step I would like to code is texture mapping. Here is my question: should I implement the texture mapping code by myself or directly use the mapping functions avaiable from OpenGL? Thanks, André "- To begin with, said the Cat, a dog''s not mad. You grant that? - I suppose so, said Alice. - Well, then, - the Cat went on - you see, a dog growls when it''s angry, and wags its tail when it''s pleased. Now I growl when I''m pleased, and wag my tail when I''m angry. Therefore I''m mad."

Share this post


Link to post
Share on other sites
quote:
Original post by tangentz
Hmm... Coding your own texture mapping sounds like fun...


~~~~
Kami no Itte ga ore ni zettai naru!


Besides being fun, is it worth? Should I gain performance coding that or not?

"- To begin with, said the Cat, a dog''s not mad. You grant that?
- I suppose so, said Alice.
- Well, then, - the Cat went on - you see, a dog growls when it''s angry, and wags its tail when it''s pleased. Now I growl when I''m pleased, and wag my tail when I''m angry. Therefore I''m mad."

Share this post


Link to post
Share on other sites
There''s no reason doing textures in software wouldn''t look as good(or better) than opengls. It will be slower though because ogl will use you graphics card to do some things in hardware w/o software. This gives the software a chance to get on with something else. So unless you want to code hardware support into your texture code(not recommended) it will be slower

Share this post


Link to post
Share on other sites
It could be faster if you threw optimized data at optimized x86 assembly on a FAF CPU. But you''d be using alot of CPU power (like all of it) for something that there''s hardware out there to do.

The GPU is just a processing unit, albeit with dedicatd 3D graphics instructions... but they only run at what? 500MHz or less? 2GHz of CPU may be able to keep pace...

Share this post


Link to post
Share on other sites
Mgmai, you should keeep quiet unless you have learned more about reality.

Current GPU''s (well, actually even down to the GF) are extremely efficient. Yes, they may run at only 500 Mhz, but they are able to process a pixel PER CYCLE - often with multiple textures. More powerfull cards actually have independent units, so they are able to process more than a pixel per cycle, in independent vertices.

With a 2.5 Ghz PIV you are 5 times as fast - but you really dont want to be so arrogant to say you can fill a pixwl (with applying textures!) in 5 cycles, or?

Boy, learn about the power and speed of hardware BEFORE giving bad advice.


Regards

Thomas Tomiczek
THONA Consulting Ltd.
(Microsoft MVP C#/.NET)

Share this post


Link to post
Share on other sites
quote:
Original post by Magmai Kai Holmlor
The GPU is just a processing unit, albeit with dedicatd 3D graphics instructions... but they only run at what? 500MHz or less? 2GHz of CPU may be able to keep pace...


man you really need to learn processor architecture if you''re going to say things like this. HZ means shit, it''s how the pipeline is designed and the bandwidth...

Share this post


Link to post
Share on other sites
quote:
Original post by Andre Luiz Silva
Well, first hello everybody,

I am starting my first attempt on a 3D Engine. I´ve coded everything from perspective projection to solid shading, so that I could have a better understanding of all the 3D stuff. I am at a point that I can draw a wireframed object loaded from an X file. The next step I would like to code is texture mapping. Here is my question: should I implement the texture mapping code by myself or directly use the mapping functions avaiable from OpenGL?



here''s a tip the more you don''t go across the ports ie the agp slot then the faster your game will be. Use as much static geometry and try to pack all that and textures onto the card for the best performance.

also I dont'' know how much you know about engine architecture etc but if you don''t know what or how a scene graph is used go back to the drawing board. Also you want ot plan out all your code before coding, TRUST ME.

Share this post


Link to post
Share on other sites
Well, thanks for all the replies. ECKO, I don´t know anything about engine architecture. If you know any article about it (except here from gamedev and flipcode) please let me know.

I am reading BLACK ART OF 3D GAME PROGRAMMING, from Lamothe. It´s an old book but it describes the fundamentals of a 3D engine, some math and a graphics pipeline.

So, my second question is: how did you guys planned your FIRST 3D Engine?

Thanks again,

"- To begin with, said the Cat, a dog''s not mad. You grant that?
- I suppose so, said Alice.
- Well, then, - the Cat went on - you see, a dog growls when it''s angry, and wags its tail when it''s pleased. Now I growl when I''m pleased, and wag my tail when I''m angry. Therefore I''m mad."

Share this post


Link to post
Share on other sites
quote:
Original post by Ecko
also I dont' know how much you know about engine architecture etc but if you don't know what or how a scene graph is used go back to the drawing board.
THAT helped me. I was thinking about a scenegraph hirachy for days now and if it could be fast enough. Haven't read much about them here an the board, although every second guy here writes his own engine.

The boost graph lib could be usefull ...

[edited by - Jonus on July 17, 2002 10:10:35 AM]

Share this post


Link to post
Share on other sites
I''m also writing my first engine now... Enter "3d engines list" in google (there are about 3-4 lists) and there are many engines with sourcecode.

I''m having a hard time loading models... Anybody here knows something about MAX Script?

Veni Vidi Vici

Share this post


Link to post
Share on other sites