preserve per-event mouse coordinates; prefer in ui signal producing codepath

src/os/gfx/os_gfx.h

@@ -71,6 +71,7 @@ struct OS_Event
   B32 right_sided;
   U32 character;
   U32 repeat_count;
+  Vec2F32 pos;
   Vec2F32 delta;
   String8List strings;
 };

src/os/gfx/win32/os_gfx_win32.c

@@ -416,6 +416,8 @@ w32_wnd_proc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
             event->key = OS_Key_RightMouseButton;
           }break;
         }
+        event->pos.x = (F32)LOWORD(lParam);
+        event->pos.y = (F32)HIWORD(lParam);
         if(release)
         {
           ReleaseCapture();

src/ui/ui_core.c

@@ -2215,8 +2215,6 @@ ui_signal_from_box(UI_Box *box)
   UI_Signal result = {0};
   result.box = box;
   result.event_flags = os_get_event_flags();
-  Vec2F32 mouse = ui_state->mouse;
-  B32 mouse_is_over = contains_2f32(box->rect, mouse);
   B32 disabled = !!(box->flags & UI_BoxFlag_Disabled);
   B32 is_focused = !!(box->flags & UI_BoxFlag_FocusHot) && !(box->flags & UI_BoxFlag_FocusHotDisabled);
   
@@ -2248,6 +2246,14 @@ ui_signal_from_box(UI_Box *box)
     }
   }
   
+  //- rjf: unpack mouse position info
+  Vec2F32 mouse = ui_state->mouse;
+  if(left_press != 0)   { mouse = left_press->pos; }
+  if(left_release != 0) { mouse = left_release->pos; }
+  if(right_press != 0)   { mouse = right_press->pos; }
+  if(right_release != 0) { mouse = right_release->pos; }
+  B32 mouse_is_over = contains_2f32(box->rect, mouse);
+  
   //- rjf: check for parent that is clipping
   if(box->flags & (UI_BoxFlag_Clickable|UI_BoxFlag_ViewScroll) && mouse_is_over)
   {