Linecast inside a box collider

Hi Everyone,

I have the following problem:

As you can see my LineCasts don't detect collisions properly. It happens because of the way I draw this grid - some of the starting points of the lines end up inside an "environment" object. As a matter of fact, I have an "environment" layer(9) and a "player" layer(10), which are self explanatory.

I was wondering... shouldn't LineCasts detect collisions even if they are inside colliders (Or colliders intersect the line)? Also, my "environment" GameObjects use Box Colliders.

I save my start and end points into ArrayLists and then I do the hit check. Here is the code for the check:

 // Check for collisions
 for (int i = 0; i < startPoints.Count; i++) {
    Vector3 start = (Vector3)startPoints[i];
    Vector3 end = (Vector3)endPoints[i];
    
    if( Physics.Linecast( start, end, layerMask ) )
     Debug.DrawLine( start, end, Color.red );
 }

My LayerMask is:

 int layerMask = 1<<10;
 layerMask = ~layerMask;

I apologize if I am repeating the question, I could not find an answer for a couple of hours, so I decided to post here.

Thanks for your time!