Rendering performance: Coordinate system orientation

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Pianist
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Location: Czech Republic

Rendering performance: Coordinate system orientation

Post by Pianist »

For Irrlicht projects it is generally used XZ=floor and Y=front/rear coordinate system.I see it is advantageous to FPS camera and gravity. I believe it may be gainful for physical model too. (I'm not sure).
My question is: Is there any low level optimisation in Irrlicht for treating(rendering) XZ=floor and Y=front/rear coordinate system? Or coordinate system choice is definitely up to developer. And in case I would define XY as floor and Z=front/rear I'll get same rendering performance??

Thanks.
sudi
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Post by sudi »

the coordinate system used looks like this.
Image
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Pianist
Posts: 14
Joined: Wed Apr 22, 2009 12:47 pm
Location: Czech Republic

Post by Pianist »

OK, thanks Sudi I can see native coordinate of Irrlicht. I would like to know relation between coordinate system and rendering performace of graphic card. Let's imagine my selection of coordinate system, see figure:

Image

XY=floor and Z=up/down

And question for some Irrlicht developer insider: Can I get same Frames Per Second for coordinate system (as is illustrated on figure) as for native Irrlicht case (XZ=floor and Y=up/down)???

Thanks to everybody.
sudi
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Joined: Fri Aug 26, 2005 8:38 pm

Post by sudi »

why would using a different coord system change performance?
the same mathfunctions work on the vectors.
We're programmers. Programmers are, in their hearts, architects, and the first thing they want to do when they get to a site is to bulldoze the place flat and build something grand. We're not excited by renovation:tinkering,improving,planting flower beds.
Pianist
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Joined: Wed Apr 22, 2009 12:47 pm
Location: Czech Republic

Post by Pianist »

Great, it sounds good.

But after all I'm afraid of using my custom coord system. I see there is FPS camera prepared for XZ=floor and it is not possible use it as it is for different coord system. So it is necesarry adjust FPS camera. And I'm affraid there would be affected more things by my custom coord system definition.
Please, do you have any idea what else will be affected?
sudi
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Joined: Fri Aug 26, 2005 8:38 pm

Post by sudi »

first of all the fps cam is for prototyping and not really meant for a real game.
and other than that why do u need a changed coord system?
We're programmers. Programmers are, in their hearts, architects, and the first thing they want to do when they get to a site is to bulldoze the place flat and build something grand. We're not excited by renovation:tinkering,improving,planting flower beds.
BlindSide
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Post by BlindSide »

Nothing will be affected by using Z-UP for example, you can set a camera's (Using camera->setUpVector()) as you like.
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