From 22c85e78ffd82127da3cc16604cb901016d26b4e Mon Sep 17 00:00:00 2001
From: Dick Hollenbeck <dick@softplc.com>
Date: Wed, 13 Mar 2013 11:17:16 -0500
Subject: [PATCH] EAGLE_PLUGIN cu layer map fix

---
 pcbnew/eagle_plugin.cpp | 32 ++++++++++++++++++++++++++++----
 pcbnew/eagle_plugin.h   |  4 +++-
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/pcbnew/eagle_plugin.cpp b/pcbnew/eagle_plugin.cpp
index 8cd93d8be3..214bbb7c7d 100644
--- a/pcbnew/eagle_plugin.cpp
+++ b/pcbnew/eagle_plugin.cpp
@@ -1158,6 +1158,10 @@ void EAGLE_PLUGIN::init( PROPERTIES* aProperties )
 {
     m_hole_count = 0;
 
+    // all cu layers are invalid until we see one in the <layers> section while board loading.
+    for( unsigned i = 0;  i < DIM(m_cu_map);  ++i )
+        m_cu_map[i] = -1;
+
     m_xpath->clear();
     m_pads_to_nets.clear();
 
@@ -1245,6 +1249,27 @@ void EAGLE_PLUGIN::loadLayerDefs( CPTREE& aLayers )
         }
     }
 
+    // establish cu layer map:
+    int ki_layer_count = 0;
+    for( EITER it = cu.begin();  it != cu.end();  ++it,  ++ki_layer_count )
+    {
+        if( ki_layer_count == 0 )
+            m_cu_map[it->number] = LAYER_N_FRONT;
+        else if( ki_layer_count == int( cu.size()-1 ) )
+            m_cu_map[it->number] = LAYER_N_BACK;
+        else
+            // some eagle boards do not have contiguous layer number sequences.
+            m_cu_map[it->number] = cu.size() - 1 - ki_layer_count;
+    }
+
+#if 0 && defined(DEBUG)
+    printf( "m_cu_map:\n" );
+    for( unsigned i=0; i<DIM(m_cu_map);  ++i )
+    {
+        printf( "\t[%d]:%d\n", i, m_cu_map[i] );
+    }
+#endif
+
     m_board->SetCopperLayerCount( cu.size() );
 
     for( EITER it = cu.begin();  it != cu.end();  ++it )
@@ -2438,7 +2463,7 @@ void EAGLE_PLUGIN::loadSignals( CPTREE& aSignals )
 }
 
 
-int EAGLE_PLUGIN::kicad_layer( int aEagleLayer )
+int EAGLE_PLUGIN::kicad_layer( int aEagleLayer ) const
 {
     /* will assume this is a valid mapping for all eagle boards until I get paid more:
 
@@ -2507,13 +2532,12 @@ int EAGLE_PLUGIN::kicad_layer( int aEagleLayer )
 
     */
 
-
     int kiLayer;
 
     // eagle copper layer:
-    if( aEagleLayer >= 1 && aEagleLayer <= 16 )
+    if( aEagleLayer >= 1 && aEagleLayer < int( DIM( m_cu_map ) ) )
     {
-        kiLayer = LAYER_N_FRONT - ( aEagleLayer - 1 );
+        return m_cu_map[aEagleLayer];
     }
 
     else
diff --git a/pcbnew/eagle_plugin.h b/pcbnew/eagle_plugin.h
index e28ad5db07..8e6ccd226c 100644
--- a/pcbnew/eagle_plugin.h
+++ b/pcbnew/eagle_plugin.h
@@ -116,6 +116,8 @@ public:
 
 private:
 
+    int         m_cu_map[17];       ///< map eagle to kicad, cu layers only.
+
     ERULES*     m_rules;            ///< Eagle design rules.
     XPATH*      m_xpath;            ///< keeps track of what we are working on within
                                     ///< XML document during a Load().
@@ -149,7 +151,7 @@ private:
     wxSize  kicad_fontz( double d ) const;
 
     /// Convert an Eagle layer to a KiCad layer.
-    static int kicad_layer( int aLayer );
+    int     kicad_layer( int aLayer ) const;
 
     /// Convert a KiCad distance to an Eagle distance.
     double  eagle( BIU d ) const            { return mm_per_biu * d; }