VG3_coll_q_new()Create an empty quadtree for collision detection.
|rect||Rectangle which the quadtree shall cover,|
normally the elements x and y are 0, and w and h give the size
|max_rect||number of objects in a (sub-)quadtree before a new sub-quadtree is created, or 0 = use default|
|max_level||highest number of nested sub-quadtrees, or 0 = use default|
Returns a pointer to the created quadtree or NULL on failure.
On error VG3_errmsg() returns: EINVAL - error in argument ENOMEM - cannot get memory
Create a new empty quadtree for collision detection and return pointer to it. A quadtree should cover the whole background of the game, that is it must have the size of the background, on which all objects are located.