TwinTails
Close, vx and vy are the horizontal and vertical velocities and ax and ay are the horizontal and vertical accelerations. Also g is the acceleration for gravity. In event 10 the acceleration is used to change the velocity and the velocity is used to change the position. Of course the player only actually is moved up and down and the terrain is changed by the horizontal position.
When the player is in the air ax is 0 and ay is g. But when the player is on the ground the acceleration's direction is changed to be along the slope.
Here is the math behind the slope acceleration:
http://www.physicsclassroom.com/class/vectors/u3l3e.cfm
Increasing the acceleration would be one possible way to boost the player. Adding a event like this to the end of the event sheet will multiply the acceleration by 10 while spacebar is down.
Key spacebar is down:
--- player: set ax to self.ax*10
--- player: set ay to self.ay*10