I have an RTS game with a camera that can be controlled by either edge-pan, gamepad analog stick or keyboard buttons (WASD). The speed and snappiness are good for the general case, but sometimes feels to slow when going to far-away places on the map. What's a good algorithm to implement some form of acceleration on the camera without making it feel less snappy? Preferably, this algorithm should work best for the analog stick, since mouse+keyboard can easily use the minimap to navigate as well.