Camera Pick Code/Tutorial

Does anyone have any code for camera picking or even know of a tutorial?

I.e Something like in b3d,

hit=CameraPick MyCam,XPixel,YPIxel

if hit
x = pickedx()
y = pickedy()
z = pickedz()
endif

Would it involve the use of a linepick function or is done with a custom matrix?

What are you exactly talking of?
As there is no camera, you can do a simple CollideRect test to find all objects the mouse pointer collides with at click for example.

I think you need to go the martix route, as Dreamora says there is no Entity Type called Camera but you do have the projection matrix to play with.

Well there is a camera entity class in what i'm using(TrinityV2) I'm just not sure how to approach it.
I keep finding links pointing towards supposedly a good tutorial on the subject but none of them are working anymore.
Anyone got a link to a working version?

I can see the projection matrix idea working if I download gl projection matrix and use a simple point in poly test on each tri. With this I could easily determine which entity is hit but I'd still be at a loss when it comes to finding out the exact x,y,z of the intersection.
I'm sure blitz returned this. Mark! MARK!

There's a lot of tutorials out there. Google for "OpenGL picking tutorial".
I used this one a couple of weeks ago: http://www.lighthouse3d.com/opengl/picking/

Thanks for that but I was under the impression that regular gl picking can only identify on a per entity basis rather than specifying an exact tri and the location of the hit?

Any idea how mark did it in b3d?

you got msn ant? add slightlyevilmonkee@...

dont mind helping out

An easy and fast way of finding the picked X, Y and Z coordinates could be reading the depth of a pixel, then creating a vector from the appropriate place of the forefront of the view frustum with the length of the depth. The picked X, Y and Z coordinates are where this vector ends.
Hah it's impossible to express such stuff in English :/
Maybe this image can help: