I noticed that on Linux horizontal scrolling (using one of those mouse wheels that can be pushed to the left and to the right like on the Logitech G502) was incorrectly bound to the mouse forwards and back buttons. This PR fixes the button assignments for those buttons (buttons 8 and 9 map to those), and it adds horizontal scrolling support for both Linux/X11 and Windows. I haven't tested whether horizontal scrolling works on macOS but looking at the scroll_wheel() handler presumably that already worked just fine.
I noticed that on Linux horizontal scrolling (using one of those mouse wheels that can be pushed to the left and to the right like on the Logitech G502) was incorrectly bound to the mouse forwards and back buttons. This PR fixes the button assignments for those buttons (buttons 8 and 9 map to those), and it adds horizontal scrolling support for both Linux/X11 and Windows. I haven't tested whether horizontal scrolling works on macOS but looking at the
scroll_wheel()handler presumably that already worked just fine.