Is it faster to use absolute coordinates or to use relative coordinates?
By using absolute (or world ) coordinates, your application doesn’t have to change the ModelView matrix as often. By using relative (or object ) coordinates, you can cut down on data storage of redundant primitives or geometry. A good analogy is an architectural software package that models a hotel. The hotel model has hundreds of thousands of rooms, most of which are identical. Certain features are identical in each room, and maybe each room has the same lamp or the same light switch or doorknob. The application might choose to keep only one doorknob model and change the ModelView matrix as needed to render the doorknob for each hotel room door. The advantage of this method is that data storage is minimized. The disadvantage is that several calls are made to change the ModelView matrix, which can reduce performance. Alternatively, the application could instead choose to keep hundreds of copies of the doorknob in memory, each with its own set of absolute coordinates. These doorknobs al
