Clarify dragging flags

src/window_manager.cc

@@ -2047,13 +2047,13 @@ int _GNW_check_buttons(Window* window, int* keyCodePtr)
         }
 
         if (button != NULL) {
-            if ((button->flags & BUTTON_FLAG_0x10) != 0
+            if ((button->flags & BUTTON_DRAG_HANDLE) != 0
                 && (mouseEvent & MOUSE_EVENT_ANY_BUTTON_DOWN) != 0
                 && (mouseEvent & MOUSE_EVENT_ANY_BUTTON_REPEAT) == 0) {
                 win_drag(window->id);
                 _button_draw(button, window, button->normalImage, true, NULL, true);
             }
-        } else if ((window->flags & WINDOW_FLAG_0x80) != 0) {
+        } else if ((window->flags & WINDOW_DRAGGABLE_BY_BACKGROUND) != 0) {
             v25 |= mouseEvent << 8;
             if ((mouseEvent & MOUSE_EVENT_ANY_BUTTON_DOWN) != 0
                 && (mouseEvent & MOUSE_EVENT_ANY_BUTTON_REPEAT) == 0) {

src/window_manager.h

@@ -42,8 +42,10 @@ typedef enum WindowFlags {
     WINDOW_MODAL = 0x10,
     WINDOW_TRANSPARENT = 0x20,
     WINDOW_FLAG_0x40 = 0x40,
-    // Draggable?
+
-    WINDOW_FLAG_0x80 = 0x80,
+    /// Specifies that the window is draggable by clicking and moving anywhere
+    /// in its background.
+    WINDOW_DRAGGABLE_BY_BACKGROUND = 0x80,
     WINDOW_MANAGED = 0x100,
 } WindowFlags;
 
@@ -52,7 +54,9 @@ typedef enum ButtonFlags {
     BUTTON_FLAG_0x02 = 0x02,
     BUTTON_FLAG_0x04 = 0x04,
     BUTTON_FLAG_DISABLED = 0x08,
-    BUTTON_FLAG_0x10 = 0x10,
+
+    /// Specifies that the button is a drag handle for parent window.
+    BUTTON_DRAG_HANDLE = 0x10,
     BUTTON_FLAG_TRANSPARENT = 0x20,
     BUTTON_FLAG_0x40 = 0x40,
     BUTTON_FLAG_GRAPHIC = 0x010000,

src/window_manager_private.cc

@@ -322,7 +322,7 @@ int _win_list_select_at(const char* title, char** items, int itemsLength, ListSe
         NULL,
         NULL,
         NULL,
-        BUTTON_FLAG_0x10);
+        BUTTON_DRAG_HANDLE);
 
     windowRefresh(win);
 
@@ -885,7 +885,7 @@ int _win_debug(char* string)
             NULL,
             NULL,
             NULL,
-            BUTTON_FLAG_0x10);
+            BUTTON_DRAG_HANDLE);
     }
 
     char temp[2];