Make scrolling speed configurable

The UI now can send a 'Scroll' key, whose value is the scrolling
amount encoded as a signed integer. This replaces the MouseWheelUp
and MouseWheelDown keys.

The NCursesUI now has a ncurses_wheel_scroll_amount ui_option that
controls that amount, it can be negative to swap scrolling direction.

Fixes #3045

1 files changed, 1 insertions, 0 deletions

diff --git a/src/main.cc b/src/main.cc
index 620a3da8..b724f122 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -437,6 +437,7 @@ void register_options()
                        "    ncurses_change_colors         bool\n"
                        "    ncurses_wheel_up_button       int\n"
                        "    ncurses_wheel_down_button     int\n"
+                       "    ncurses_wheel_scroll_amount   int\n"
                        "    ncurses_shift_function_key    int\n"
                        "    ncurses_builtin_key_parser    bool\n",
                        UserInterface::Options{});