Author Topic: Inverted Y axis coordinated system  (Read 1404 times)

Offline kakashi

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Inverted Y axis coordinated system
« on: June 15, 2009, 07:57:59 pm »

Is normal that the Y axis is positive goes downwards??
is this a bad configuration in the camera or is the engine coordinated system??
which is the coordinated system?
How can I configure to Y positive goes Up and X positive goes right??

Thanks a lot!!

Offline EgonOlsen

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Re: Inverted Y axis coordinated system
« Reply #1 on: June 15, 2009, 08:12:03 pm »
As stated in the docs somewhere: x goes right, y goes down and z goes into the screen (all for positive values). That's how it is, there is no way to change this. If you are using another coordinate system for some other third party lib or in your own code, you have to convert between the two, which is pretty easy.
The reason for this order lies in the software renderer. To ease some calculations, i wanted positive z to point into the screen (anything else is highly counter-intuitive to me anyway, but that's just me...). Therefore, jPCT uses the "normal" GL like coordinate system just rotated by 180 around X.