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Index › Programming Questions & Help › OpenGL and 3D Libraries › Y-Axis Points Down

dandandandan YaBB Newbies Offline Posts: 3	Y-Axis Points Down Dec 22nd, 2008, 1:00am   Hi I have set up a 3d axis, drawing a line for the x-axis, y-axis, and z-axis. Positive X values point to the right, positive Z values point out towards the screen, and positive Y values point DOWN. If I want the positive values of the Y-axis to point UP instead of DOWN, what would I change?

sw01 Full Member Offline Posts: 175	Re: Y-Axis Points Down Reply #1 - Dec 22nd, 2008, 1:09am   Code: translate(0, someHeight, 0); ... int getY(oldY){ int newY = - oldY; return newY; } ?

dandandandan YaBB Newbies Offline Posts: 3	Re: Y-Axis Points Down Reply #2 - Dec 22nd, 2008, 1:30am   Yes I realize I can just represent all my Y-coordinates as negative, but it gets a bit hairy when working with the mechanics, angles, and rotations. I was just wondering if it's possible to change the coordinate system to one where Y points up?

sw01 Full Member Offline Posts: 175	Re: Y-Axis Points Down Reply #3 - Dec 22nd, 2008, 1:35am   Sorry, I was half joking when I wrote that. But since you are likely to be working with vectors, why not subclass them with similar methods?

dandandandan YaBB Newbies Offline Posts: 3	Re: Y-Axis Points Down Reply #4 - Dec 22nd, 2008, 1:39am   Thanks I'll look in to overriding the classes to account for it, I didn't think of that.

JohnG Ex Member	Re: Y-Axis Points Down Reply #5 - Dec 22nd, 2008, 2:07pm   scale(1,-1,1); should do it.

sw01 Full Member Offline Posts: 175	Re: Y-Axis Points Down Reply #6 - Dec 22nd, 2008, 3:03pm   That's a better answer by million-fold.