Eeschema: Allow auto-wiring / drawing from unconnected bus and graphic line endpoints

Fixes https://gitlab.com/kicad/code/kicad/issues/7537

eeschema/sch_connection.h

@@ -127,6 +127,8 @@ public:
         return ( m_type == CONNECTION_TYPE::NET );
     }
 
+    bool IsUnconnected() const { return ( m_type == CONNECTION_TYPE::NONE ); }
+
     bool IsDirty() const { return m_dirty; }
     void SetDirty() { m_dirty = true; }
     void ClearDirty() { m_dirty = false; }

eeschema/sch_item.h

@@ -64,6 +64,8 @@ enum FIELDS_AUTOPLACED
 enum DANGLING_END_T
 {
     UNKNOWN = 0,
+    GRAPHIC_START_END,
+    GRAPHIC_END_END,
     WIRE_START_END,
     WIRE_END_END,
     BUS_START_END,

eeschema/sch_line.cpp

@@ -566,19 +566,29 @@ SCH_LINE* SCH_LINE::MergeOverlap( SCH_SCREEN* aScreen, SCH_LINE* aLine, bool aCh
 
 void SCH_LINE::GetEndPoints( std::vector <DANGLING_END_ITEM>& aItemList )
 {
-    if( IsGraphicLine() )
+    DANGLING_END_T startType, endType;
-        return;
 
-    if( ( GetLayer() == LAYER_BUS ) || ( GetLayer() == LAYER_WIRE ) )
+    switch( GetLayer() )
     {
-        DANGLING_END_ITEM item( (GetLayer() == LAYER_BUS) ? BUS_START_END : WIRE_START_END, this,
+    case LAYER_WIRE:
-                                m_start );
+        startType = WIRE_START_END;
-        aItemList.push_back( item );
+        endType = WIRE_END_END;
-
+        break;
-        DANGLING_END_ITEM item1( (GetLayer() == LAYER_BUS) ? BUS_END_END : WIRE_END_END, this,
+    case LAYER_BUS:
-                                 m_end );
+        startType = BUS_START_END;
-        aItemList.push_back( item1 );
+        endType = BUS_END_END;
+        break;
+    default:
+        startType = GRAPHIC_START_END;
+        endType = GRAPHIC_END_END;
+        break;
     }
+
+    DANGLING_END_ITEM item( startType, this, m_start );
+    aItemList.push_back( item );
+
+    DANGLING_END_ITEM item1( endType, this, m_end );
+    aItemList.push_back( item1 );
 }
 
 
@@ -590,32 +600,36 @@ bool SCH_LINE::UpdateDanglingState( std::vector<DANGLING_END_ITEM>& aItemList,
 
     m_startIsDangling = m_endIsDangling = true;
 
-    if( GetLayer() == LAYER_WIRE )
+    for( DANGLING_END_ITEM item : aItemList )
     {
-        for( DANGLING_END_ITEM item : aItemList )
+        if( item.GetItem() == this )
-        {
+            continue;
-            if( item.GetItem() == this )
-                continue;
 
-            if(     item.GetType() == BUS_START_END ||
+        if( ( IsWire()
-                    item.GetType() == BUS_END_END  ||
+              && ( item.GetType() == BUS_START_END || item.GetType() == BUS_END_END
-                    item.GetType() == BUS_ENTRY_END )
+                   || item.GetType() == BUS_ENTRY_END ) )
-                continue;
+            || ( IsBus()
+                 && ( item.GetType() == WIRE_START_END || item.GetType() == WIRE_END_END
+                      || item.GetType() == PIN_END ) )
+            || ( IsGraphicLine()
+                 && ( item.GetType() != GRAPHIC_START_END && item.GetType() != GRAPHIC_END_END ) ) )
+            continue;
 
-            if( m_start == item.GetPosition() )
+        if( m_start == item.GetPosition() )
-                m_startIsDangling = false;
+            m_startIsDangling = false;
 
-            if( m_end == item.GetPosition() )
+        if( m_end == item.GetPosition() )
-                m_endIsDangling = false;
+            m_endIsDangling = false;
 
-            if( !m_startIsDangling && !m_endIsDangling )
+        if( !m_startIsDangling && !m_endIsDangling )
-                break;
+            break;
-        }
     }
-    else if( GetLayer() == LAYER_BUS || IsGraphicLine() )
+
+    if( IsBus() || IsGraphicLine() )
     {
-        // Lines on the notes layer and the bus layer cannot be tested for dangling ends.
+        // Force unchanged return state for graphic lines and busses
-        previousStartState = previousEndState = m_startIsDangling = m_endIsDangling = false;
+        previousStartState = m_startIsDangling;
+        previousEndState = m_endIsDangling;
     }
 
     return ( previousStartState != m_startIsDangling ) || ( previousEndState != m_endIsDangling );
@@ -903,6 +917,11 @@ bool SCH_LINE::IsWire() const
     return ( GetLayer() == LAYER_WIRE );
 }
 
+bool SCH_LINE::IsBus() const
+{
+    return ( GetLayer() == LAYER_BUS );
+}
+
 
 bool SCH_LINE::UsesDefaultStroke() const
 {

eeschema/sch_line.h

@@ -266,6 +266,13 @@ public:
      */
     bool IsWire() const;
 
+    /**
+     * Returns true if the line is a bus.
+     *
+     * @return true if this line is on the bus layer.
+     */
+    bool IsBus() const;
+
 private:
     bool doIsConnected( const wxPoint& aPosition ) const override;
 };

eeschema/sch_painter.cpp

@@ -1272,13 +1272,13 @@ void SCH_PAINTER::draw( const SCH_LINE *aLine, int aLayer )
         }
     }
 
-    if( aLine->IsStartDangling() )
+    if( aLine->IsStartDangling() && aLine->IsWire() )
     {
         drawDanglingSymbol( aLine->GetStartPoint(), getLineWidth( aLine, drawingShadows ),
                             drawingShadows );
     }
 
-    if( aLine->IsEndDangling() )
+    if( aLine->IsEndDangling() && aLine->IsWire() )
     {
         drawDanglingSymbol( aLine->GetEndPoint(), getLineWidth( aLine, drawingShadows ),
                             drawingShadows );

eeschema/tools/ee_selection_tool.cpp

@@ -329,6 +329,7 @@ int EE_SELECTION_TOOL::Main( const TOOL_EVENT& aEvent )
     {
         bool displayWireCursor = false;
         bool displayBusCursor = false;
+        bool displayLineCursor = false;
         KIID rolloverItem = lastRolloverItem;
         m_additive = m_subtractive = m_exclusive_or = false;
 
@@ -374,15 +375,21 @@ int EE_SELECTION_TOOL::Main( const TOOL_EVENT& aEvent )
                         OPT_TOOL_EVENT newEvt;
                         SCH_CONNECTION* connection = collector[0]->Connection();
 
-                        if( connection && connection->IsBus() )
+                        if( ( connection && ( connection->IsNet() || connection->IsUnconnected() ) )
-                        {
+                            || collector[0]->Type() == SCH_COMPONENT_T )
-                            newEvt = EE_ACTIONS::drawBus.MakeEvent();
-                        }
-                        else
                         {
                             newEvt = EE_ACTIONS::drawWire.MakeEvent();
                         }
-                    
+                        else if( connection && connection->IsBus() )
+                        {
+                            newEvt = EE_ACTIONS::drawBus.MakeEvent();
+                        }
+                        else if( collector[0]->Type() == SCH_LINE_T
+                                 && static_cast<SCH_LINE*>( collector[0] )->IsGraphicLine() )
+                        {
+                            newEvt = EE_ACTIONS::drawLines.MakeEvent();
+                        }
+
                         auto* params = newEvt->Parameter<DRAW_SEGMENT_EVENT_PARAMS*>();
                         auto* newParams = new DRAW_SEGMENT_EVENT_PARAMS();
 
@@ -390,7 +397,6 @@ int EE_SELECTION_TOOL::Main( const TOOL_EVENT& aEvent )
                         newParams->quitOnDraw = true;
                         newEvt->SetParameter( newParams );
 
-
                         getViewControls()->ForceCursorPosition( true, snappedCursorPos );
                         newEvt->SetMousePosition( snappedCursorPos );
                         newEvt->SetHasPosition( true );
@@ -586,13 +592,19 @@ int EE_SELECTION_TOOL::Main( const TOOL_EVENT& aEvent )
                     {
                         SCH_CONNECTION* connection = collector[0]->Connection();
 
-                        if( connection && connection->IsBus() )
+                        if( ( connection && ( connection->IsNet() || connection->IsUnconnected() ) )
+                            || collector[0]->Type() == SCH_COMPONENT_T )
+                        {
+                            displayWireCursor = true;
+                        }
+                        else if( connection && connection->IsBus() )
                         {
                             displayBusCursor = true;
                         }
-                        else
+                        else if( collector[0]->Type() == SCH_LINE_T
+                                 && static_cast<SCH_LINE*>( collector[0] )->IsGraphicLine() )
                         {
-                            displayWireCursor = true;
+                            displayLineCursor = true;
                         }
 
                         getViewControls()->ForceCursorPosition( true, snappedCursorPos );
@@ -654,6 +666,10 @@ int EE_SELECTION_TOOL::Main( const TOOL_EVENT& aEvent )
             {
                 m_nonModifiedCursor = KICURSOR::LINE_BUS;
             }
+            else if( displayLineCursor )
+            {
+                m_nonModifiedCursor = KICURSOR::LINE_GRAPHIC;
+            }
             else if( rolloverItem != niluuid )
             {
                 m_nonModifiedCursor = KICURSOR::HAND;