getting started back

(L) [2012/10/10] [ost by palebluedot] [getting started] Wayback!

Hi,

I'm just getting started with raytracing and to begin with, I decided to do simple ray-sphere collision checks. So far I've tried algebraic and geometric collision checks and both produce elongations of my sphere as it moves in the XY plane ( camera is on negative Z ). Does anyone have any clues onto why this stretching occurs?

Here is an example:
[LINK http://glsl.heroku.com/e#4283.8]

Thanks

(L) [2012/10/11] [ost by h3r3] [getting started] Wayback!

That is normal and is due to the perspective (field of view), it's like when you take a photo with a fisheye lens.
Just use higher value for your constant "focus" and you will get less perspective deformation.

(L) [2012/10/11] [ost by Tristan] [getting started] Wayback!

Haha wow that's quite a development environment you've got there!

(L) [2012/10/11] [ost by graphicsMan] [getting started] Wayback!

With a simple pinhole camera model this is normal and to be expected.

(L) [2012/10/11] [ost by palebluedot] [getting started] Wayback!

Oh, you know, I've been banging my head with this for a week now! It is a big relief to hear someone knowledgeable telling you "that's the way its supposed to work". Thank you very much =)

PS: My book should have stated so earlier, so I could account for this happening and not try to figure out what I was doing wrong.

(L) [2012/10/12] [ost by palebluedot] [getting started] Wayback!

Reality agrees with you...
[LINK http://www.quehacerenmurcia.com/wp-content/uploads/2011/04/estenopeica.jpg]

(L) [2012/10/12] [ost by palebluedot] [getting started] Wayback!

[LINK http://proyectozapato.files.wordpress.com/2011/11/pinchazo_estenopeica_l.jpg]

(L) [2012/10/12] [ost by palebluedot] [getting started] Wayback!

[LINK http://www.fotolaser.com/?portfolios=expo-chuquiure]