Algodoo

Arrow keys to move, A and D to aim. W to fire.

I just had a stroke of genius! This is a scripted watergun that works at any speed and uses no custom variables! I was thinking about how nice it would be to have local variables tucked inside a given geometry that could be found in the script menu and traveled with it when saved as a phunlet, then I realized most geometries have a bunch of these, many of which just sit there unused! This spawner uses the controller acceleration and text size of itself and the "barrel" to save its X and Y position and also its position from the last time it fired. From there it calculates its velocity and adds that to the vels of the water being spawned. To get the angle right, I just used and amplified e.normal, which is a pair of numbers adding up to one that define the angle of the collision force.

You can test the accuracy of this thing by firing at the pink block while stationary, then without moving the gun, accelerating to full speed.
EDIT: sacrificed speed for accuracy, no longer miscalculates or misfires. Also weighted the gun so it doesn't sag slowly anymore.

EDIT 2: My circle has a textScale? whatwhat WHAT?