Pcbnew: more work on a better algorithm to calculate the full ratsnest.

Lee algorithm replaced by a Minimun Spanning Tree algo (using Prim's algorithm ).
Tested on a 5350 pads board, it is more than 100 times faster.
Also fix a crash when clicking on tool  "delete selected items" (main horizontal toolbar),
and remove this tool (currently, no code in Pcbnew for this tool)

include/wxBasePcbFrame.h

@@ -352,7 +352,11 @@ public:
      */
     void TraceModuleRatsNest( wxDC* aDC );
 
-    void Build_Board_Ratsnest( wxDC* DC );
+    /**
+     * Function Build_Board_Ratsnest.
+     * Calculates the full ratsnest depending only on pads.
+     */
+    void Build_Board_Ratsnest();
 
     /**
      *  function Displays the general ratsnest

pcbnew/CMakeLists.txt

@@ -132,6 +132,7 @@ set(PCBNEW_SRCS
     magnetic_tracks_functions.cpp
     menubar_modedit.cpp
     menubar_pcbframe.cpp
+    minumun_spanning_tree.cpp
     mirepcb.cpp
     modedit.cpp
     modedit_onclick.cpp

pcbnew/edit.cpp

@@ -66,7 +66,6 @@ void PCB_EDIT_FRAME::Process_Special_Functions( wxCommandEvent& event )
 
     int         itmp;
     INSTALL_UNBUFFERED_DC( dc, DrawPanel );
-    BOARD_ITEM* DrawStruct = GetCurItem();
     MODULE* module;
 
     DrawPanel->CrossHairOff( &dc );
@@ -1080,8 +1079,8 @@ void PCB_EDIT_FRAME::Process_Special_Functions( wxCommandEvent& event )
 
     default:
         wxString msg;
-        msg.Printf( wxT( "PCB_EDIT_FRAME::Process_Special_Functions() id %d error" ),
-                    DrawStruct->Type() );
+        msg.Printf( wxT( "PCB_EDIT_FRAME::Process_Special_Functions() unknown event id %d" ),
+                    id );
         DisplayError( this, msg );
         break;
     }

pcbnew/minumun_spanning_tree.cpp

+/**
+ * @file minumun_spanning_tree.cpp
+ */
+
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2011 Jean-Pierre Charras
+ * Copyright (C) 2004-2011 KiCad Developers, see change_log.txt for contributors.
+ *
+ * derived from this article:
+ * http://compprog.wordpress.com/2007/11/09/minimal-spanning-trees-prims-algorithm
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you may find one here:
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ * or you may search the http://www.gnu.org website for the version 2 license,
+ * or you may write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+#include <limits.h>
+
+#include "minumun_spanning_tree.h"
+#include "class_pad.h"
+
+/*
+ * The class MIN_SPAN_TREE calculates the rectilinear minimum spanning tree
+ * of a set of points (pads usually having the same net)
+ * using the Prim's algorithm.
+ */
+
+/*
+ *  Prim's Algorithm
+ *   Step 0
+ *   Pick any vertex as a starting vertex. (Call it S).
+ *   Mark it with any given flag, say 1.
+ *
+ *   Step 1
+ *   Find the nearest neighbour of S (call it P1).
+ *   Mark both P1 and the edge SP1.
+ *   cheapest unmarked edge in the graph that doesn't close a marked circuit.
+ *   Mark this edge.
+ *
+ *   Step 2
+ *   Find the nearest unmarked neighbour to the marked subgraph
+ *   (i.e., the closest vertex to any marked vertex).
+ *   Mark it and the edge connecting the vertex.
+ *
+ *   Step 3
+ *   Repeat Step 2 until all vertices are marked.
+ *   The marked subgraph is a minimum spanning tree.
+ */
+MIN_SPAN_TREE::MIN_SPAN_TREE()
+{
+    MSP_Init( 0 );
+}
+
+
+void MIN_SPAN_TREE::MSP_Init( int aNodesCount )
+{
+    m_Size = aNodesCount;
+    inTree.clear();
+    linkedTo.clear();
+    distTo.clear();
+
+    if( m_Size == 0 )
+        return;
+
+    // Reserve space in memory
+    inTree.reserve( m_Size );
+    linkedTo.reserve( m_Size );
+    distTo.reserve( m_Size );
+
+    // Initialize values:
+    for( int ii = 0; ii < m_Size; ii++ )
+    {
+        // Initialise dist with infinity:
+        distTo.push_back( INT_MAX );
+
+        // Mark all nodes as NOT beeing in the minimum spanning tree:
+        inTree.push_back( 0 );
+
+        linkedTo.push_back( 0 );
+    }
+}
+
+
+/* updateDistances(int target)
+ *   should be called immediately after target is added to the tree;
+ *   updates dist so that the values are correct (goes through target's
+ *   neighbours making sure that the distances between them and the tree
+ *   are indeed minimum)
+ */
+void MIN_SPAN_TREE::updateDistances( int target )
+{
+    for( int ii = 0; ii < m_Size; ++ii )
+    {
+        if( !inTree[ii] )   // no need to evaluate weight for already in tree items
+        {
+            int weight = GetWeight( target, ii );
+            if( (weight > 0) && (distTo[ii] > weight ) )
+            {
+                distTo[ii]   = weight;
+                linkedTo[ii] = target;
+            }
+        }
+    }
+}
+
+
+void MIN_SPAN_TREE::BuildTree()
+{
+    /* Add the first node to the tree */
+    inTree[0] = 1;
+    updateDistances( 0 );
+
+    for( int treeSize = 1; treeSize < m_Size; ++treeSize )
+    {
+        // Find the node with the smallest distance to the tree
+        int min = -1;
+        for( int ii = 0; ii < m_Size; ++ii )
+        {
+            if( !inTree[ii] )
+            {
+                if( (min == -1) || (distTo[min] > distTo[ii]) )
+                    min = ii;
+            }
+        }
+
+        inTree[min] = 1;
+        updateDistances( min );
+    }
+}

pcbnew/minumun_spanning_tree.h

+/**
+ * @file minumun_spanning_tree.h
+ */
+
+#include <vector>
+
+/**
+ * @brief The class MIN_SPAN_TREE calculates the rectilinear minimum spanning tree
+ * of a set of points (pads usually having the same net)
+ * this class is an abstract class because you must provide the function
+ *     int  GetWeight( int aItem1, int aItem2 )
+ * that calculate the distance between 2 items
+ * MIN_SPAN_TREE does not know anything about the actual items to link
+ * by the tree
+ */
+class MIN_SPAN_TREE
+{
+protected:
+    int m_Size;               /* The number of nodes in the graph
+                               */
+private:
+    std::vector<char> inTree; /* inTree[ii] is a flag set to 1 if the node ii
+                               *  is already in the minimum spanning tree; 0 otherwise
+                               */
+    std::vector<int>  linkedTo; /* linkedTo[ii] holds the index of the node ii would have to be
+                                 *  linked to in order to get a distance of d[ii]
+                                 * NOTE: linkedTo[0] is the starting point of the tree
+                                 * linkedTo[1] is the first linked point to use
+                                 * ii and linkedTo[ii] are the 2 ends of an edge in the graph
+                                 */
+    std::vector<int> distTo;  /* distTo[ii] is the distance between node ii and the minimum spanning
+                               * tree;
+                               * this is initially infinity (INT_MAX);
+                               * if ii is already in the tree, then d[ii] is undefined;
+                               * this is just a temporary variable. It's not necessary but speeds
+                               * up execution considerably (by a factor of n)
+                               */
+public:
+    MIN_SPAN_TREE();
+    void MSP_Init( int aNodesCount );
+    void BuildTree();
+
+    int GetWhoTo( int aIdx )
+    {
+        return linkedTo[aIdx];
+    }
+
+
+    int GetDist( int aIdx )
+    {
+        return distTo[aIdx];
+    }
+
+    /**
+     * Function GetWeight
+     * calculates the weight between 2 items
+     * NOTE: The weight between a node and itself should be 0
+     * It is virtual pure, you must provide your GetWeight function
+     * @param aItem1 = first item
+     * @param aItem2 = other item
+     * @return the weight between items ( usually the distance )
+     */
+    virtual int  GetWeight( int aItem1, int aItem2 ) = 0;
+
+private:
+
+    /**
+     * Function updateDistances
+     *   should be called immediately after target is added to the tree;
+     *   updates d so that the values are correct (goes through target's
+     *   neighbours making sure that the distances between them and the tree
+     *   are indeed minimum)
+     * @param target = index of curr item
+     */
+    void updateDistances( int aTarget );
+
+};

pcbnew/tool_pcb.cpp

@@ -204,11 +204,12 @@ void PCB_EDIT_FRAME::ReCreateHToolbar()
     m_HToolBar->AddTool( ID_OPEN_MODULE_EDITOR, wxEmptyString, KiBitmap( modedit_xpm ),
                          _( "Open module editor" ) );
 
+#if 0
+    // Not yet existing commands
     m_HToolBar->AddSeparator();
     m_HToolBar->AddTool( wxID_CUT, wxEmptyString, KiBitmap( cut_button_xpm ),
                          _( "Cut selected item" ) );
 
-#if 0
     m_HToolBar->AddTool( wxID_COPY, wxEmptyString, KiBitmap( copy_button_xpm ),
                          _( "Copy selected item" ) );