Fix click-drag events for dragging markers

Clicking and dragging markers accumulates flags from multiple operators
in a way that can't be interpreted when combine.

Follow tweak behavior for cancelling click-drag events.

1 files changed, 34 insertions, 35 deletions

diff --git a/source/blender/windowmanager/intern/wm_event_system.c b/source/blender/windowmanager/intern/wm_event_system.c
index 20940c59679..b3b99b0b7fc 100644
--- a/source/blender/windowmanager/intern/wm_event_system.c
+++ b/source/blender/windowmanager/intern/wm_event_system.c
@@ -3157,44 +3157,40 @@ static int wm_handlers_do(bContext *C, wmEvent *event, ListBase *handlers)
   if (ELEM(event->type, MOUSEMOVE, INBETWEEN_MOUSEMOVE)) {
     /* Test for #WM_CLICK_DRAG events. */
 
-    /* NOTE(@campbellbarton): Needed so drag can be used for editors that support both click
+    /* NOTE(@campbellbarton): Ignore `action` so drag can be used for editors that use both click
      * selection and passing through the drag action to box select. See #WM_generic_select_modal.
-     * Unlike click, accept `action` when break isn't set.
-     * Operators can return `OPERATOR_FINISHED | OPERATOR_PASS_THROUGH` which results
-     * in `action` setting #WM_HANDLER_HANDLED, but not #WM_HANDLER_BREAK. */
-    if ((action & WM_HANDLER_BREAK) == 0 || wm_action_not_handled(action)) {
-      if (win->event_queue_check_drag) {
-        if (WM_event_drag_test(event, event->prev_click_xy)) {
-          win->event_queue_check_drag_handled = true;
-
-          const int prev_xy[2] = {UNPACK2(event->xy)};
-          const short prev_val = event->val;
-          const short prev_type = event->type;
-          const uint8_t prev_modifier = event->modifier;
-          const short prev_keymodifier = event->keymodifier;
-
-          copy_v2_v2_int(event->xy, event->prev_click_xy);
-          event->val = KM_CLICK_DRAG;
-          event->type = event->prev_type;
-          event->modifier = event->prev_click_modifier;
-          event->keymodifier = event->prev_click_keymodifier;
-
-          CLOG_INFO(WM_LOG_HANDLERS, 1, "handling PRESS_DRAG");
+     * In the case of marker select-drag the combinations of (pass-through / finished / modal)
+     * can accumulate to have flags set that they can't be properly interpreted here.
+     * Instead `win->event_queue_check_drag` is cleared in `wm_event_do_handlers`. */
+    if (win->event_queue_check_drag) {
+      if (WM_event_drag_test(event, event->prev_click_xy)) {
+        win->event_queue_check_drag_handled = true;
+
+        const int prev_xy[2] = {UNPACK2(event->xy)};
+        const short prev_val = event->val;
+        const short prev_type = event->type;
+        const uint8_t prev_modifier = event->modifier;
+        const short prev_keymodifier = event->keymodifier;
+
+        copy_v2_v2_int(event->xy, event->prev_click_xy);
+        event->val = KM_CLICK_DRAG;
+        event->type = event->prev_type;
+        event->modifier = event->prev_click_modifier;
+        event->keymodifier = event->prev_click_keymodifier;
+
+        CLOG_INFO(WM_LOG_HANDLERS, 1, "handling PRESS_DRAG");
 
-          action |= wm_handlers_do_intern(C, win, event, handlers);
+        WM_event_print(event);
 
-          event->keymodifier = prev_keymodifier;
-          event->modifier = prev_modifier;
-          event->val = prev_val;
-          event->type = prev_type;
-          copy_v2_v2_int(event->xy, prev_xy);
+        action |= wm_handlers_do_intern(C, win, event, handlers);
 
-          win->event_queue_check_click = false;
-          if (!((action & WM_HANDLER_BREAK) == 0 || wm_action_not_handled(action))) {
-            /* Only disable when handled as other handlers may use this drag event. */
-            win->event_queue_check_drag = false;
-          }
-        }
+        event->keymodifier = prev_keymodifier;
+        event->modifier = prev_modifier;
+        event->val = prev_val;
+        event->type = prev_type;
+        copy_v2_v2_int(event->xy, prev_xy);
+
+        win->event_queue_check_click = false;
       }
     }
     else {
@@ -3270,7 +3266,6 @@ static int wm_handlers_do(bContext *C, wmEvent *event, ListBase *handlers)
     }
     else {
       win->event_queue_check_click = false;
-      win->event_queue_check_drag = false;
     }
   }
   else if (ISMOUSE_WHEEL(event->type) || ISMOUSE_GESTURE(event->type)) {
@@ -3720,6 +3715,10 @@ void wm_event_do_handlers(bContext *C)
       /* Builtin tweak, if action is break it removes tweak. */
       wm_tweakevent_test(C, event, action);
 
+      if (action & WM_HANDLER_BREAK) {
+        win->event_queue_check_drag = false;
+      }
+
       if ((action & WM_HANDLER_BREAK) == 0) {
         /* NOTE: setting subwin active should be done here, after modal handlers have been done. */
         if (event->type == MOUSEMOVE) {