Gizmo: add the ability to postpone refreshing while tweaking

This resolves a logical problem using tweak as a fallback tool.
See: T66304#828742

The select action would immediately show the gizmo underneath it,
then the tweak would be handled by the gizmo instead of moving the item
under the cursor.

Currently this works by hiding the gizmo until the tweak event ends.
While it's simpler to check if the gizmo received a mouse-down event,
it causes flickering before each drag event which feels like a glitch.

This is optional for each gizmo type because there are cases where this
can be useful to activate the gizmo immediately (mesh rip for example).

1 files changed, 43 insertions, 7 deletions

diff --git a/source/blender/windowmanager/gizmo/intern/wm_gizmo_map.c b/source/blender/windowmanager/gizmo/intern/wm_gizmo_map.c
index 97bb203bcf6..f176f0e5df4 100644
--- a/source/blender/windowmanager/gizmo/intern/wm_gizmo_map.c
+++ b/source/blender/windowmanager/gizmo/intern/wm_gizmo_map.c
@@ -304,16 +304,47 @@ static GHash *WM_gizmomap_gizmo_hash_new(const bContext *C,
   return hash;
 }
 
+eWM_GizmoFlagMapDrawStep WM_gizmomap_drawstep_from_gizmo_group(const wmGizmoGroup *gzgroup)
+{
+  eWM_GizmoFlagMapDrawStep step;
+  if (gzgroup->type->flag & WM_GIZMOGROUPTYPE_3D) {
+    step = WM_GIZMOMAP_DRAWSTEP_3D;
+  }
+  else {
+    step = WM_GIZMOMAP_DRAWSTEP_2D;
+  }
+  return step;
+}
+
+void WM_gizmomap_tag_refresh_drawstep(wmGizmoMap *gzmap, const eWM_GizmoFlagMapDrawStep drawstep)
+{
+  BLI_assert((uint)drawstep < WM_GIZMOMAP_DRAWSTEP_MAX);
+  if (gzmap) {
+    gzmap->update_flag[drawstep] |= (GIZMOMAP_IS_PREPARE_DRAW | GIZMOMAP_IS_REFRESH_CALLBACK);
+  }
+}
+
 void WM_gizmomap_tag_refresh(wmGizmoMap *gzmap)
 {
   if (gzmap) {
-    /* We might want only to refresh some, for tag all steps. */
     for (int i = 0; i < WM_GIZMOMAP_DRAWSTEP_MAX; i++) {
       gzmap->update_flag[i] |= (GIZMOMAP_IS_PREPARE_DRAW | GIZMOMAP_IS_REFRESH_CALLBACK);
     }
   }
 }
 
+bool WM_gizmomap_tag_refresh_check(wmGizmoMap *gzmap)
+{
+  if (gzmap) {
+    for (int i = 0; i < WM_GIZMOMAP_DRAWSTEP_MAX; i++) {
+      if (gzmap->update_flag[i] & (GIZMOMAP_IS_PREPARE_DRAW | GIZMOMAP_IS_REFRESH_CALLBACK)) {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
 static bool gizmo_prepare_drawing(wmGizmoMap *gzmap,
                                   wmGizmo *gz,
                                   const bContext *C,
@@ -359,7 +390,8 @@ static void gizmomap_prepare_drawing(wmGizmoMap *gzmap,
   /* only active gizmo needs updating */
   if (gz_modal) {
     if ((gz_modal->parent_gzgroup->type->flag & WM_GIZMOGROUPTYPE_DRAW_MODAL_ALL) == 0) {
-      if (wm_gizmogroup_is_visible_in_drawstep(gz_modal->parent_gzgroup, drawstep)) {
+      if ((gz_modal->parent_gzgroup->hide.any == 0) &&
+          wm_gizmogroup_is_visible_in_drawstep(gz_modal->parent_gzgroup, drawstep)) {
         if (gizmo_prepare_drawing(gzmap, gz_modal, C, draw_gizmos, drawstep)) {
           gzmap->update_flag[drawstep] &= ~GIZMOMAP_IS_PREPARE_DRAW;
         }
@@ -369,9 +401,13 @@ static void gizmomap_prepare_drawing(wmGizmoMap *gzmap,
     }
   }
 
+  /* Allow refresh functions to ask to be refreshed again, clear before the loop below. */
+  const bool do_refresh = gzmap->update_flag[drawstep] & GIZMOMAP_IS_REFRESH_CALLBACK;
+  gzmap->update_flag[drawstep] &= ~GIZMOMAP_IS_REFRESH_CALLBACK;
+
   for (wmGizmoGroup *gzgroup = gzmap->groups.first; gzgroup; gzgroup = gzgroup->next) {
     /* check group visibility - drawstep first to avoid unnecessary call of group poll callback */
-    if (!wm_gizmogroup_is_visible_in_drawstep(gzgroup, drawstep) ||
+    if ((gzgroup->hide.any != 0) || !wm_gizmogroup_is_visible_in_drawstep(gzgroup, drawstep) ||
         !WM_gizmo_group_type_poll(C, gzgroup->type)) {
       continue;
     }
@@ -379,7 +415,7 @@ static void gizmomap_prepare_drawing(wmGizmoMap *gzmap,
     /* Needs to be initialized on first draw. */
     /* XXX weak: Gizmo-group may skip refreshing if it's invisible
      * (map gets untagged nevertheless). */
-    if (gzmap->update_flag[drawstep] & GIZMOMAP_IS_REFRESH_CALLBACK) {
+    if (do_refresh) {
       /* force refresh again. */
       gzgroup->init_flag &= ~WM_GIZMOGROUP_INIT_REFRESH;
     }
@@ -396,7 +432,7 @@ static void gizmomap_prepare_drawing(wmGizmoMap *gzmap,
     }
   }
 
-  gzmap->update_flag[drawstep] &= ~(GIZMOMAP_IS_REFRESH_CALLBACK | GIZMOMAP_IS_PREPARE_DRAW);
+  gzmap->update_flag[drawstep] &= ~GIZMOMAP_IS_PREPARE_DRAW;
 }
 
 /**
@@ -716,7 +752,7 @@ wmGizmo *wm_gizmomap_highlight_find(wmGizmoMap *gzmap,
     /* If it were important we could initialize here,
      * but this only happens when events are handled before drawing,
      * just skip to keep code-path for initializing gizmos simple. */
-    if ((gzgroup->init_flag & WM_GIZMOGROUP_INIT_SETUP) == 0) {
+    if ((gzgroup->hide.any != 0) || ((gzgroup->init_flag & WM_GIZMOGROUP_INIT_SETUP) == 0)) {
       continue;
     }
 
@@ -1126,7 +1162,7 @@ void WM_gizmomap_message_subscribe(bContext *C,
                                    struct wmMsgBus *mbus)
 {
   for (wmGizmoGroup *gzgroup = gzmap->groups.first; gzgroup; gzgroup = gzgroup->next) {
-    if ((gzgroup->init_flag & WM_GIZMOGROUP_INIT_SETUP) == 0 ||
+    if ((gzgroup->hide.any != 0) || (gzgroup->init_flag & WM_GIZMOGROUP_INIT_SETUP) == 0 ||
         !WM_gizmo_group_type_poll(C, gzgroup->type)) {
       continue;
     }