Images flickable has performance bug

resources/Core/I_Scene.qml

@@ -304,19 +304,22 @@ QSObject {
 
     //! Delete all selected objects (Node + Link)
     function  deleteSelectedObjects() {
+        scene.selectionModel.notifySelectedObject = false;
         // Delete objects
         Object.entries(scene.selectionModel.selectedModel).forEach(([key, value]) => {
-            if(value.objectType === NLSpec.ObjectType.Node) {
+            if (value.objectType === NLSpec.ObjectType.Node) {
                 if (!value.guiConfig.locked)
                     scene.deleteNode(value._qsUuid);
             }
-            if(value.objectType === NLSpec.ObjectType.Container) {
+            if (value.objectType === NLSpec.ObjectType.Container) {
                 scene.deleteContainer(value._qsUuid);
             }
-            if(value.objectType === NLSpec.ObjectType.Link) {
+            if (value.objectType === NLSpec.ObjectType.Link) {
                 scene.unlinkNodes(value.inputPort._qsUuid, value.outputPort._qsUuid)
             }
         });
+
+        scene.selectionModel.notifySelectedObject = true;
 		// Clear the selection
         scene.selectionModel.clear();
     }

resources/Core/SelectionModel.qml

@@ -14,6 +14,10 @@ QtObject {
     //! Uuids of all exist objects in scene.
     property var existObjects: []
 
+    //! If notifySelectedObject is set to false, the selector object must handle this event..
+    //! and call the selectedModelChanged() signal.
+    property bool notifySelectedObject : true
+
     onExistObjectsChanged: checkSelectedObjects();
 
     /* Signals
@@ -26,10 +30,19 @@ QtObject {
 
     //! Check all selected objects when necessary, i.e undo/redo
     function checkSelectedObjects () {
+        notifySelectedObject = false;
+        var changed = false;
         Object.keys(selectedModel).forEach(uuid => {
-                                 if (!existObjects.includes(uuid))
-                                        remove(uuid);
+                                if (!existObjects.includes(uuid)) {
+                                    remove(uuid);
+                                    changed = true;
+                                }
                              });
+
+        notifySelectedObject = true;
+
+        if (changed)
+            selectedModelChanged();
     }
 
     //! Clear all objects from selection model
@@ -38,11 +51,14 @@ QtObject {
         Object.entries(selectedModel).forEach(([key, value]) => {
                 delete selectedModel[key];
         });
-        selectedModelChanged();
+
+        if (notifySelectedObject)
+            selectedModelChanged();
     }
 
 
     //! Clear all objects (except one with qsUuid) from selection model
+    //! never sends signal for selection model change! as it will be followed by another event
     function clearAllExcept(qsUuid : string) {
         // delete all objects
         Object.entries(selectedModel).forEach(([key, value]) => {
@@ -53,24 +69,30 @@ QtObject {
 
     //! Remove an object from selection model
     function remove(qsUuid : string) {
-        if(isSelected(qsUuid)) {
+        if (isSelected(qsUuid)) {
             delete selectedModel[qsUuid];
-            selectedModelChanged();
+
+            if (notifySelectedObject)
+                selectedModelChanged();
         }
     }
 
     //! Select object nodes (Add Node object to SelectionModel)
     function selectNode(node: Node) {
         //! clear selection model when selection changed.
         selectedModel[node._qsUuid] = node;
-        selectedModelChanged();
+
+        if (notifySelectedObject)
+            selectedModelChanged();
     }
 
     //! Select container
     function selectContainer(container: Container) {
         //! clear selection model when selection changed.
         selectedModel[container._qsUuid] = container;
-        selectedModelChanged();
+
+        if (notifySelectedObject)
+            selectedModelChanged();
     }
 
     //! Select Link objects  (Add link object to SelectionModel)
@@ -80,7 +102,8 @@ QtObject {
 
         // Add Link object into selected model.
         selectedModel[link._qsUuid] = link;
-        selectedModelChanged();
+        if (notifySelectedObject)
+            selectedModelChanged();
     }
 
     //! Check an object is selected or not
@@ -104,6 +127,9 @@ QtObject {
 
     //! Selects all nodes and links in the scene
     function selectAll(nodes, links, containers) {
+        var notifySelectedObjectSession = notifySelectedObject;
+        notifySelectedObject = false;
+
         clear();
 
         Object.values(nodes).forEach(node => {
@@ -117,5 +143,10 @@ QtObject {
         Object.values(containers).forEach(container => {
             selectContainer(container);
         })
+
+        notifySelectedObject = notifySelectedObjectSession;
+
+        if (notifySelectedObject)
+            selectedModelChanged();
     }
 }

resources/View/Helpers/SelectionHelperView.qml

@@ -91,6 +91,9 @@ Item {
         running: false
 
         onTriggered: {
+            // Disable sending signals temporarily for performance improvement
+            scene.selectionModel.notifySelectedObject = false;
+
             // clear selection model
             scene.selectionModel.clear();
 
@@ -101,13 +104,17 @@ Item {
                                                   selectionRubberBandItem.height);
             var selectedObj = scene.findNodesInContainerItem(selectionRubberBandRect);
             selectedObj.forEach(node =>  {
+                if (node.objectType === NLSpec.ObjectType.Node) {
+                    scene.selectionModel.selectNode(node);
+
+                } else if (node.objectType === NLSpec.ObjectType.Container) {
+                    scene.selectionModel.selectContainer(node);
+                }
+            }); // todo: why don't we select the LINKS?
 
-                if (node.objectType === NLSpec.ObjectType.Node)
-                    scene.selectionModel.selectNode(node)
-                else if (node.objectType === NLSpec.ObjectType.Container) {
-                    scene.selectionModel.selectContainer(node)
-                                    }
-            });
+            scene.selectionModel.notifySelectedObject = true;
+            // todo: should we check actual change?
+            scene.selectionModel.selectedModelChanged();
 
             if (!sceneSession.marqueeSelectionMode)
                 resetMarqueeDimensions();

resources/View/ImagesFlickable.qml

@@ -17,8 +17,12 @@ Rectangle {
 
     property SelectionModel selectionModel: scene?.selectionModel ?? null
 
+    property var selectedItems : Object.values(selectionModel?.selectedModel ?? ({}))
+
     property I_Node         node
 
+    property bool selectedAlone : selectedItems.length === 1 && node === selectedItems[0]
+
     /* Object Properties
     * ****************************************************************************************/
     color: "#1e1e1e"

resources/View/NodesRect.qml

@@ -29,28 +29,10 @@ I_NodesRect {
             width: modelData.guiConfig.width - 6
             height: modelData.guiConfig.height * 0.35
             x: modelData.guiConfig.position.x + 3
-            y: modelData.guiConfig.position.y - height - 5
+            y: modelData.guiConfig.position.y - height - 5 - (selectedAlone ? 45 : 0)
             scene: root.scene
             sceneSession: root.sceneSession
             node: modelData
-
-            Connections {
-                property SelectionModel selectionModel: root.scene.selectionModel
-                target: selectionModel
-                function onSelectedModelChanged() {
-                    if (!objectSelectionView.hasSelectedObject)
-                        imageFlickable.y = Qt.binding(function() { return modelData.guiConfig.position.y - height - 5;});
-                    Object.values(selectionModel.selectedModel).forEach(node =>{
-                        if (imageFlickable.node === node) {
-                            imageFlickable.y = Qt.binding(function() { return modelData.guiConfig.position.y - height - 49;});
-                            return;
-                        }
-                        else
-                            imageFlickable.y = Qt.binding(function() { return modelData.guiConfig.position.y - height - 5;});
-                    })
-                }
-            }
-
         }
     }
 }