so you dont want the camera to go through objects? well, don't move the camera directly, create a box (or any shape), and move it as if it is the camera, and at the end of the loop, position the camera inside this box (so it won't be visible)
now how could that help? you can easily check collision between objects, so simply check if the box is colliding with some object, if so then the camera is colliding with the object, you should perform an action (move backwards or whatever)
also, it would be easier and more efficient to use a physics plugin (like fulcrum physics or dark physics) or a collision plugin (sparky's collision), it would save much of your time