Attempt to make the MacOS mouse more precise.

src/device/mouse.c

@@ -379,6 +379,18 @@ atomic_double_add(_Atomic double *var, double val)
     atomic_store(var, temp);
 }
 
+void
+mouse_scale_fx(double x)
+{
+    atomic_double_add(&mouse_x, ((double) x) * mouse_sensitivity);
+}
+
+void
+mouse_scale_fy(double y)
+{
+    atomic_double_add(&mouse_y, ((double) y) * mouse_sensitivity);
+}
+
 void
 mouse_scale_x(int x)
 {
@@ -391,6 +403,15 @@ mouse_scale_y(int y)
     atomic_double_add(&mouse_y, ((double) y) * mouse_sensitivity);
 }
 
+void
+mouse_scalef(double x, double y)
+{
+    pclog("DPI = %lf (%lfx%lf)\n", plat_get_dpi(), monitors[0].mon_res_x, monitors[0].mon_res_y);
+
+    mouse_scale_fx(x);
+    mouse_scale_fy(y);
+}
+
 void
 mouse_scale(int x, int y)
 {

src/include/86box/mouse.h

@@ -85,8 +85,11 @@ extern void            mouse_subtract_coords(int *delta_x, int *delta_y, int *o_
 extern  int            mouse_moved(void);
 extern  int            mouse_state_changed(void);
 extern  int            mouse_mbut_changed(void);
+extern void            mouse_scale_fx(double x);
+extern void            mouse_scale_fy(double y);
 extern void            mouse_scale_x(int x);
 extern void            mouse_scale_y(int y);
+extern void            mouse_scalef(double x, double y);
 extern void            mouse_scale(int x, int y);
 extern void            mouse_set_z(int z);
 extern void            mouse_clear_z(void);

src/qt/macos_event_filter.mm

@@ -33,7 +33,7 @@ CocoaEventFilter::nativeEventFilter(const QByteArray &eventType, void *message,
                 || [event type] == NSEventTypeLeftMouseDragged
                 || [event type] == NSEventTypeRightMouseDragged
                 || [event type] == NSEventTypeOtherMouseDragged) {
-                mouse_scale([event deltaX], [event deltaY]);
+                mouse_scalef((double) [event deltaX], (double) [event deltaY]);
                 return true;
             }
             if ([event type] == NSEventTypeScrollWheel) {