ID:2604808
 
(See the best response by Magicsofa.)

I have no idea how to start.

I want to develop a system for a shooting game, where the mouse becomes the aim of the game, and the left button the trigger. Where with the click, the player fires the projectile in the direction in which the course is located.

* But the feature needs to be enabled and disabled.
Best response
There are a bunch of built-in procs that handle mouse actions. Look in the reference for:

MouseMove()
MouseDrag()
MouseDown()
MouseUp()

You'll also most likely need to be calculating angles between the player and mouse pointer, and create vector components from it (dx and dy) so your projectiles go the right way.

There's probably some libraries and tutorials if you need examples...