Don't export hidden models to STEP.

Fixes https://gitlab.com/kicad/code/kicad/issues/5451

utils/kicad2step/pcb/kicadmodel.cpp

@@ -2,6 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2016 Cirilo Bernardo <cirilo.bernardo@gmail.com>
+ * Copyright (C) 2016-2020 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -31,17 +32,16 @@
 
 
 KICADMODEL::KICADMODEL() :
+    m_hide( false ),
     m_scale( 1.0, 1.0, 1.0 ),
     m_offset( 0.0, 0.0, 0.0 ),
     m_rotation( 0.0, 0.0, 0.0 )
 {
-    return;
 }
 
 
 KICADMODEL::~KICADMODEL()
 {
-    return;
 }
 
 
@@ -61,9 +61,13 @@ bool KICADMODEL::Read( SEXPR::SEXPR* aEntry )
     SEXPR::SEXPR* child = aEntry->GetChild( 1 );
 
     if( child->IsSymbol() )
+    {
         m_modelname = child->GetSymbol();
+    }
     else if( child->IsString() )
+    {
         m_modelname = child->GetString();
+    }
     else
     {
         std::ostringstream ostr;
@@ -76,9 +80,12 @@ bool KICADMODEL::Read( SEXPR::SEXPR* aEntry )
     {
         child = aEntry->GetChild( i );
 
-        if( !child->IsList() )
-            continue;
-
+        if( child->IsSymbol() && child->GetSymbol() == "hide" )
+        {
+            m_hide = true;
+        }
+        else if( child->IsList() )
+        {
             std::string name = child->GetChild( 0 )->GetSymbol();
             bool ret = true;
 
@@ -117,6 +124,7 @@ bool KICADMODEL::Read( SEXPR::SEXPR* aEntry )
             if( !ret )
                 return false;
         }
+    }
 
     return true;
 }

utils/kicad2step/pcb/kicadmodel.h

@@ -38,8 +38,10 @@ public:
     virtual ~KICADMODEL();
 
     bool Read( SEXPR::SEXPR* aEntry );
+    bool Hide() const { return m_hide; }
 
     std::string m_modelname;
+    bool        m_hide;
     TRIPLET     m_scale;
     TRIPLET     m_offset;
     TRIPLET     m_rotation;

utils/kicad2step/pcb/kicadmodule.cpp

@@ -159,7 +159,11 @@ bool KICADMODULE::parseModel( SEXPR::SEXPR* data )
         return false;
     }
 
+    if( mp->Hide() )
+        delete mp;
+    else
         m_models.push_back( mp );
+
     return true;
 }