Refactor `button & ~MOD_MASK' as `STRIP_BUTTON_MODIFIERS(button)'.

This refactors all instances of bitwise-ANDs with `~MOD_MASK'. There is
a handful of more complex instances I left unchanged (in cube.c, midend.c,
and twiddle.c), since those AND with `~MOD_MASK | MOD_NUM_KEYPAD' or
similar. I don't think it's worth writing a macro for those cases.

Also document this new macro's usage in devel.but.

1 files changed, 1 insertions, 1 deletions

diff --git a/pearl.c b/pearl.c
index 51897b0..9599317 100644
--- a/pearl.c
+++ b/pearl.c
@@ -2167,7 +2167,7 @@ static char *interpret_move(const game_state *state, game_ui *ui,
     char tmpbuf[80];
 
     bool shift = button & MOD_SHFT, control = button & MOD_CTRL;
-    button &= ~MOD_MASK;
+    button = STRIP_BUTTON_MODIFIERS(button);
 
     if (IS_MOUSE_DOWN(button)) {
 	ui->cursor_active = false;