In 2077 what makes someone a criminal? Getting into the extension and saying it doesn't work, without even executing the hedgehog movement action.

So how does it work?

Everything runs on this single majesty of action:

Physics and allat, the core of the extension, not using this action is the same thing as not having the extension, the magic starts there, an object with a hedgehog platformer character behavior attached to it and some platforms with the hedgehog platform behavior attached to it.

Start (pre-events)

At the start of the frame (pre-events) the input conditions are set to return false, so if you use "Is (input) pressed or simulated" will return false unless you simulate it or send input when running the hedgehog physics.

Hedgehog physics action

This is what happends inside the infamous hedgehog physics action.

Jump frames status get updated and the object moves, either normally, or by forces (if 'Use forces' is on) then if default controls are on, the input on these are checked, and control input is executed.

Control input checks for jump, left, right, acceleration and friction, Then we go to the ground angle calculation.

In ground angle calculation, the origin points of the rays is calculated, at the start they are just positioned on the sides of the object in general, then the automatic points are calculated, throwing a raycast on each side of the object, the intersection on each side are set as the origin points of the rays from now on.

Unless you use custom points for the rays, then these are checked to override the last points. And now that it is done, the angle rays get casted, using the last obtained points as their origin point.

Now we enter the speed calculation. In here, ground speed gets capped to the max speed, then x and y speed are calculated out of ground speed (if the object is grounded), here we also add the gravity to y speed and cap the x and y speed.

And now, the collision is on the run.

The ground angle gets calculated with the results of the previous rays casted and after that, most of the collision is run, then we check if the object got on a ground with floor detection, after that, if it's on a ground, floor magnet is applied, speed on landing is calculated and slope factor is applied.

Then ceil collision and ceil angle calculation is the rest of the work, it's the same as ground angle calculation but for ceilings.