Ledge Swapping Mechanic

I was briefly assigned to work on a control mechanic for the game. I worked on allowing the Avatar the ability to jump to another ledge. This would apply when the Avatar is already hanging on a ledge, but needs to move around to the other side without climbing up.

Going into this, I had little information on the actual avatar movement mechanics, but I figured it would be a good exercise to learn more about it. Fortunately, there was already a movement controller (a movement controller is a class that governs how an object moves given a certain state) that was similar to what I needed to accomplish. This was in the climbing movement controller which governed the movement when the Avatar needed to climb up from a ledge. This was similar for two reasons. First, it used ray casting to see if the ledge connected to a valid platform. Second, it handled the movement of the Avatar automatically (most other movement controllers take in the player's input).

With this in mind, I set out to program the ledge swapping ability. To start, I had to figure out which way I needed to ray cast. To set the direction, I needed to get which side of the ledge the player was on. If he was the right side, I needed to set the ray's position forward and to the right of the player's position; I then needed to ray cast to the left to see if a ledge existed on the other side. If the player was on the left side, I simply needed to set the ray's position left and forward instead, and then send the ray right. This handled the logic I needed to determine if the player could swap to the other ledge in the first place.

The second task was the actual movement which was a tad trickier than I anticipated. I asked Blake to help me understand his climbing movement code. With a good bit of help from him, we were able to get the player to snap over to the other ledge by using the position given by the previous ray cast (which determined if he could grab the other ledge in the first place). We did run into a little tiff about the player not latching on to the ledge, but that was fixed by re-oriented the player's facing so it faced the wall properly (it's hard to tell if the player is facing the wall when the player is just a box on the windows version).

After all that work, the ledge swap mechanic works very well, and the player can swap to another ledge, given that such a ledge exists, at the press of a button. In addition, I learned a more about ray casting which is quite useful in 3D programming.