On platforms with PERIPHERAL_TYPE_PAD, navigating through menus and
options can be cumbersome if moving the cursor freely around the
screen.
Therefore, this commit instead defines a list of (X, Y) coordinates that
the cursor can jump to. The implementation also attempts to guess which
direction the cursor should jump to for the previous/next point, and
hence determine which button should be pressed by the user.
This has several advantages:
- `camera` no longer needs to define public functions for each
peripheral type.
- Peripheral-related is now no longer tighly coupled to human_player,
so peripheral logic can be reused elsewhere e.g.: on menus.
- Makes camera_update_touch consistent compared to equivalent functions,
since now `pan` has now been moved to `camera` (as it should be).
The PS1 port relies on a heap for primitives since the GPU renders the
scene asynchronously. However, SDL-based platforms render primitives
synchronously, so structures can be allocated on the stack instead.
Xavier Del Campo Romero