eeschema: Fix slow redraw on net highlighting (by redrawing only modified items)

Fixes: lp:1806197
https://bugs.launchpad.net/kicad/+bug/1806197

eeschema/cross-probing.cpp

@@ -81,10 +81,17 @@ void SCH_EDIT_FRAME::ExecuteRemoteCommand( const char* cmdline )
             m_SelectedNetName = FROM_UTF8( text );
 
             SetStatusText( _( "Selected net: " ) + m_SelectedNetName );
-            SetCurrentSheetHighlightFlags();
-            // Be sure hightlight change will be redrawn in any case
-            GetGalCanvas()->GetView()->RecacheAllItems();
-            GetGalCanvas()->GetView()->MarkTargetDirty( KIGFX::TARGET_NONCACHED );
+            std::vector<EDA_ITEM*> itemsToRedraw;
+            SetCurrentSheetHighlightFlags( &itemsToRedraw );
+
+            // Be sure hightlight change will be redrawn
+            KIGFX::VIEW* view = GetGalCanvas()->GetView();
+
+            for( auto item : itemsToRedraw )
+                view->Update( (KIGFX::VIEW_ITEM*)item, KIGFX::VIEW_UPDATE_FLAGS::REPAINT );
+
+            //view->MarkTargetDirty( KIGFX::TARGET_NONCACHED );
+            GetGalCanvas()->Refresh();
         }
 
         return;

eeschema/hierarch.cpp

@@ -299,7 +299,7 @@ void SCH_EDIT_FRAME::DisplayCurrentSheet()
     }
 
     // Some items (wires, labels) can be highlighted. So prepare the highlight flag:
-    SetCurrentSheetHighlightFlags();
+    SetCurrentSheetHighlightFlags( nullptr );
 
     GetCanvas()->Refresh();
 }

eeschema/highlight_connection.cpp

@@ -36,9 +36,11 @@
 
 #include <netlist_object.h>
 
+// List of items having the highlight option modified, therefore need to be redrawn
 
 bool SCH_EDIT_FRAME::HighlightConnectionAtPosition( wxPoint aPosition )
 {
+    std::vector<EDA_ITEM*> itemsToRedraw;
     m_SelectedNetName = "";
     bool buildNetlistOk = false;
 
@@ -69,28 +71,42 @@ bool SCH_EDIT_FRAME::HighlightConnectionAtPosition( wxPoint aPosition )
 
     SendCrossProbeNetName( m_SelectedNetName );
     SetStatusText( "selected net: " + m_SelectedNetName );
-    SetCurrentSheetHighlightFlags();
-    // Be sure hightlight change will be redrawn in any case
-    GetGalCanvas()->GetView()->RecacheAllItems();
-    GetGalCanvas()->GetView()->MarkTargetDirty( KIGFX::TARGET_NONCACHED );
+    SetCurrentSheetHighlightFlags( &itemsToRedraw );
 
+    // Be sure hightlight change will be redrawn
+    KIGFX::VIEW* view = GetGalCanvas()->GetView();
+
+    for( auto item : itemsToRedraw )
+        view->Update( (KIGFX::VIEW_ITEM*)item, KIGFX::VIEW_UPDATE_FLAGS::REPAINT );
+
+    //view->MarkTargetDirty( KIGFX::TARGET_NONCACHED );
+    GetGalCanvas()->Refresh();
     return buildNetlistOk;
 }
 
 
-bool SCH_EDIT_FRAME::SetCurrentSheetHighlightFlags()
+bool SCH_EDIT_FRAME::SetCurrentSheetHighlightFlags( std::vector<EDA_ITEM*>* aItemsToRedrawList )
 {
     SCH_SCREEN* screen = m_CurrentSheet->LastScreen();
 
     // Disable highlight flag on all items in the current screen
     for( SCH_ITEM* ptr = screen->GetDrawItems(); ptr; ptr = ptr->Next() )
     {
+        if( ptr->GetState( BRIGHTENED ) && aItemsToRedrawList )
+            aItemsToRedrawList->push_back( ptr );
+
         ptr->SetState( BRIGHTENED, false );
 
+
         if( ptr->Type() == SCH_SHEET_T )
         {
             for( SCH_SHEET_PIN& pin : static_cast<SCH_SHEET*>( ptr )->GetPins() )
+            {
+                if( ptr->GetState( BRIGHTENED ) && aItemsToRedrawList )
+                    aItemsToRedrawList->push_back( &pin );
+
                 pin.SetState( BRIGHTENED, false );
+            }
         }
     }
 
@@ -111,6 +127,9 @@ bool SCH_EDIT_FRAME::SetCurrentSheetHighlightFlags()
         {
             obj1->m_Comp->SetState( BRIGHTENED, true );
 
+            if( aItemsToRedrawList )
+                aItemsToRedrawList->push_back( obj1->m_Comp );
+
             //if a bus is associated with this net highlight it as well
             if( obj1->m_BusNetCode )
             {
@@ -118,7 +137,12 @@ bool SCH_EDIT_FRAME::SetCurrentSheetHighlightFlags()
                 {
                     if( obj2 && obj2->m_Comp && obj2->m_SheetPath == *m_CurrentSheet &&
                         obj1->m_BusNetCode == obj2->m_BusNetCode )
+                    {
+                        if( aItemsToRedrawList )
+                            aItemsToRedrawList->push_back( obj2->m_Comp );
+
                         obj2->m_Comp->SetState( BRIGHTENED, true );
+                    }
                 }
             }
         }

eeschema/sch_edit_frame.h

@@ -647,10 +647,13 @@ public:
      * Set or reset the BRIGHTENED of connected objects inside the current sheet,
      * according to the highlighted net name.
      *
+     * @param aItemsToRedrawList is the list of modified items (flag BRIGHTENED modified)
+     * that must be redrawn.
+     * Can be NULL
      * @return true if the flags are correctly set, and false if something goes wrong
      * (duplicate sheet names)
      */
-    bool SetCurrentSheetHighlightFlags();
+    bool SetCurrentSheetHighlightFlags( std::vector<EDA_ITEM*>* aItemsToRedrawList );
 
     /**
      * @return a filename that can be used in plot and print functions