How do I send a raycast from the mouse pointer position? Say for exmaple that I want to have a 3D ball at the position of where the mouse pointer "hits" the 3D world. How would I do that? I know there's c_trace, and Im guessing thats part of the answer. But the problem Im having is how youre supposed to translate the mouse's x, y coordinates in 2D space to a position/angle in 3D space from where the c_trace is supposed to occur.

Help?

EDIT:
Managed to Solve it now. Solution was to use cameras position for from vector, and vec_for_screen as to vector (i placed it 1000 units away).

So, for example:
c_trace(camera.x, vec_for_screen(vector(mouse_cursor.x, mouse_cursor.y, 1000), camera), IGNORE_ME);
vec_set(me.x, target);

vec_for_screen/vec_to_screen

Wow great! Thanks.

Hm.. But this can just give me the from vector in c_trace. How do I get a to vector? Again, what I want to do is to put something where mouse pointer hits 3d-world. Imagine that I wanna put a laser crosshair dot where mouse pointer is. So if it hits far away, then itll be very small, and if close itll be big. I dont see how to accomplish that with vec_for_screen since it needs you to tell it where to put the entity in z.

Also wanna point out that it isnt a 1st person view..

Edited main post with pic.

EDIT:
Hm, maybe you could take camera position and position of placed entity (vec_for_screen), and then use c_trace to "draw" a line between them, but that goes beyond the placed entity?

EDIT:
Managed to Solve it now. Solution was to use cameras position for from vector, and vec_for_screen as to vector (i placed it 1000 units away).

correct, glad you solved it by yourself.