stimuli: raise threshold for range -> button from 1 to 64

This means that we switch in the middle of the range, increasing
the zones in which the control can be safely "parked", and also
avoiding issues with devices that have difficulties reaching the
end of the range.

Also updated test/stimin

src/compiler/test/stimin

@@ -43,11 +43,12 @@ EOF
 #------------------------------------------------------------------------------
 
 ptest "stimuli, input, MIDI: range -> button" -c -q \
-    -v sx -m 0=63 -m 0=127 -m 0=0 <<EOF
+    -v sx -m 0=63 -m 0=64 -m 0=127 -m 0=0 <<EOF
 midi "foo" { bar = range(1, 0); }
 sx = button(bar);
 EOF
 expect <<EOF
+0
 1
 1
 0
@@ -56,11 +57,12 @@ EOF
 #------------------------------------------------------------------------------
 
 ptest "stimuli, input, MIDI: range -> toggle" -c -q \
-    -v sx -m 0=63 -m 0=127 -m 0=0 <<EOF
+    -v sx -m 0=63 -m 0=64 -m 0=127 -m 0=0 <<EOF
 midi "foo" { bar = range(1, 0); }
 sx = toggle(bar);
 EOF
 expect <<EOF
+0
 1
 1
 0

src/renderer/stimuli.c

@@ -80,7 +80,7 @@ static void midi_proc_diff_linear(struct s_midi_ctrl *ct, int value)
 
 static void midi_proc_range_button(struct s_midi_ctrl *ct, int value)
 {
-	regs_set(&ct->regs, !!value);
+	regs_set(&ct->regs, value > 63);
 }
 
 static void midi_proc_diff_button(struct s_midi_ctrl *ct, int value)