Fix incorrect (broken) canvas type saving in config.

The config was saving a canvas type EDA_DRAW_FRAME member not always accurately initialized.
And the last canvas opened frame setup was saved, not necessary a frame having a canvas type that can be set by user.
This is a broken feature especially because the footprint viewer has a fixed canvas setting.

common/legacy_gal/eda_draw_frame.cpp

@@ -46,7 +46,6 @@
 #include <math/box2.h>
 #include <lockfile.h>
 #include <trace_helpers.h>
-//#include "../eeschema/sch_draw_panel.h"
 #include <wx/fontdlg.h>
 #include <wx/snglinst.h>
 #include <view/view.h>
@@ -78,9 +77,6 @@ static const wxString traceScrollSettings( wxT( "KicadScrollSettings" ) );
 
 ///@{
 /// \ingroup config
-
-const wxChar EDA_DRAW_FRAME::CANVAS_TYPE_KEY[] = wxT( "canvas_type" );
-
 static const wxString FirstRunShownKeyword( wxT( "FirstRunShown" ) );
 
 ///@}
@@ -221,6 +217,7 @@ EDA_DRAW_FRAME::EDA_DRAW_FRAME( KIWAY* aKiway, wxWindow* aParent,
 EDA_DRAW_FRAME::~EDA_DRAW_FRAME()
 {
     delete m_socketServer;
+
     for( auto socket : m_sockets )
     {
         socket->Shutdown();
@@ -1072,7 +1069,7 @@ EDA_DRAW_PANEL_GAL::GAL_TYPE EDA_DRAW_FRAME::LoadCanvasTypeSetting()
     wxConfigBase* cfg = Kiface().KifaceSettings();
 
     if( cfg )
-        canvasType = (EDA_DRAW_PANEL_GAL::GAL_TYPE) cfg->ReadLong( CANVAS_TYPE_KEY,
+        canvasType = (EDA_DRAW_PANEL_GAL::GAL_TYPE) cfg->ReadLong( GetCanvasTypeKey(),
                                                                    EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE );
 
     if( canvasType < EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE
@@ -1096,6 +1093,28 @@ EDA_DRAW_PANEL_GAL::GAL_TYPE EDA_DRAW_FRAME::LoadCanvasTypeSetting()
 
 bool EDA_DRAW_FRAME::saveCanvasTypeSetting( EDA_DRAW_PANEL_GAL::GAL_TYPE aCanvasType )
 {
+    // Not all classes derived from EDA_DRAW_FRAME can save the canvas type, because some
+    // have a fixed type, or do not have a option to set the canvas type (they inherit from
+    // a parent frame)
+    FRAME_T allowed_frames[] =
+    {
+        FRAME_SCH, FRAME_PCB, FRAME_PCB_MODULE_EDITOR
+    };
+
+    bool allow_save = false;
+
+    for( int ii = 0; ii < 3; ii++ )
+    {
+        if( m_Ident == allowed_frames[ii] )
+        {
+            allow_save = true;
+            break;
+        }
+    }
+
+    if( !allow_save )
+        return false;
+
     if( aCanvasType < EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE
             || aCanvasType >= EDA_DRAW_PANEL_GAL::GAL_TYPE_LAST )
     {
@@ -1106,7 +1125,7 @@ bool EDA_DRAW_FRAME::saveCanvasTypeSetting( EDA_DRAW_PANEL_GAL::GAL_TYPE aCanvas
     wxConfigBase* cfg = Kiface().KifaceSettings();
 
     if( cfg )
-        return cfg->Write( CANVAS_TYPE_KEY, (long) aCanvasType );
+        return cfg->Write( GetCanvasTypeKey(), (long) aCanvasType );
 
     return false;
 }

common/legacy_wx/eda_draw_frame.cpp

@@ -81,9 +81,6 @@ static const wxString traceScrollSettings( wxT( "KicadScrollSettings" ) );
 
 ///@{
 /// \ingroup config
-
-const wxChar EDA_DRAW_FRAME::CANVAS_TYPE_KEY[] = wxT( "canvas_type" );
-
 static const wxString FirstRunShownKeyword( wxT( "FirstRunShown" ) );
 
 ///@}
@@ -1325,7 +1322,7 @@ EDA_DRAW_PANEL_GAL::GAL_TYPE EDA_DRAW_FRAME::LoadCanvasTypeSetting()
     wxConfigBase* cfg = Kiface().KifaceSettings();
 
     if( cfg )
-        canvasType = (EDA_DRAW_PANEL_GAL::GAL_TYPE) cfg->ReadLong( CANVAS_TYPE_KEY,
+        canvasType = (EDA_DRAW_PANEL_GAL::GAL_TYPE) cfg->ReadLong( GetCanvasTypeKey(),
                                                                    EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE );
 
     if( canvasType < EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE
@@ -1349,17 +1346,39 @@ EDA_DRAW_PANEL_GAL::GAL_TYPE EDA_DRAW_FRAME::LoadCanvasTypeSetting()
 
 bool EDA_DRAW_FRAME::saveCanvasTypeSetting( EDA_DRAW_PANEL_GAL::GAL_TYPE aCanvasType )
 {
+    // Not all classes derived from EDA_DRAW_FRAME can save the canvas type, because some
+    // have a fixed type, or do not have a option to set the canvas type (they inherit from
+    // a parent frame)
+    FRAME_T allowed_frames[] =
+    {
+        FRAME_SCH, FRAME_PCB, FRAME_PCB_MODULE_EDITOR
+    };
+
+    bool allow_save = false;
+
+    for( int ii = 0; ii < 3; ii++ )
+    {
+        if( m_Ident == allowed_frames[ii] )
+        {
+            allow_save = true;
+            break;
+        }
+    }
+
+    if( !allow_save )
+        return false;
+
     if( aCanvasType < EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE
             || aCanvasType >= EDA_DRAW_PANEL_GAL::GAL_TYPE_LAST )
     {
-        assert( false );
+        wxASSERT( false );
         return false;
     }
 
     wxConfigBase* cfg = Kiface().KifaceSettings();
 
     if( cfg )
-        return cfg->Write( CANVAS_TYPE_KEY, (long) aCanvasType );
+        return cfg->Write( GetCanvasTypeKey(), (long) aCanvasType );
 
     return false;
 }

include/class_draw_panel_gal.h

@@ -58,7 +58,8 @@ class EDA_DRAW_PANEL_GAL : public wxScrolledCanvas
 {
 public:
     enum GAL_TYPE {
-        GAL_TYPE_NONE,      ///< Not used
+        GAL_TYPE_UNKNOWN = -1,  ///< not specified: a GAL engine must be set by the client
+        GAL_TYPE_NONE = 0,      ///< GAL not used (the legacy wxDC engine is used)
         GAL_TYPE_OPENGL,        ///< OpenGL implementation
         GAL_TYPE_CAIRO,         ///< Cairo implementation
         GAL_TYPE_LAST           ///< Sentinel, do not use as a parameter

include/draw_frame.h

@@ -60,14 +60,17 @@ namespace KIGFX
 /// \ingroup config
 
 /// User units
-static const wxString UserUnitsEntryKeyword( wxT( "Units" ) );
+#define UserUnitsEntryKeyword "Units"
 /// Nonzero to show grid (suffix)
-static const wxString ShowGridEntryKeyword( wxT( "ShowGrid" ) );
+#define ShowGridEntryKeyword "ShowGrid"
 /// Grid color ID (suffix)
-static const wxString GridColorEntryKeyword( wxT( "GridColor" ) );
+#define GridColorEntryKeyword "GridColor"
 /// Most recently used grid size (suffix)
-static const wxString LastGridSizeIdKeyword( wxT( "_LastGridSize" ) );
+#define LastGridSizeIdKeyword "_LastGridSize"
 
+/// The key to store the canvas type in config. This is the base key.
+/// can be a suffix if the canvas_type in config is specific to a frame
+#define CanvasTypeKeyBase "canvas_type"
 ///@}
 
 
@@ -230,8 +233,14 @@ protected:
     bool saveCanvasImageToFile( const wxString& aFileName,
                                 wxBitmapType aBitmapType = wxBITMAP_TYPE_PNG );
 
-    ///> Key in KifaceSettings to store the canvas type.
+    /** @return the key in KifaceSettings to store the canvas type.
-    static const wxChar CANVAS_TYPE_KEY[];
+     * the base version returns only CanvasTypeKeyBase.
+     * Can be overriden to return a key specific of a frame name
+     */
+    virtual wxString GetCanvasTypeKey()
+    {
+        return CanvasTypeKeyBase;
+    }
 
 public:
     EDA_DRAW_FRAME( KIWAY* aKiway, wxWindow* aParent,
@@ -893,7 +902,7 @@ public:
     /**
      * Returns the canvas type stored in the application settings.
      */
-    static EDA_DRAW_PANEL_GAL::GAL_TYPE LoadCanvasTypeSetting();
+    EDA_DRAW_PANEL_GAL::GAL_TYPE LoadCanvasTypeSetting();
 
     /**
      * Use to switch between standard and GAL-based canvas.

include/pcb_base_frame.h

@@ -622,8 +622,6 @@ public:
     }
 
     ///> Key in KifaceSettings to store the canvas type.
-    static const wxChar CANVAS_TYPE_KEY[];
-
     static const wxChar AUTO_ZOOM_KEY[];
     static const wxChar ZOOM_KEY[];
 

pcbnew/footprint_edit_frame.cpp

@@ -228,8 +228,13 @@ FOOTPRINT_EDIT_FRAME::FOOTPRINT_EDIT_FRAME( KIWAY* aKiway, wxWindow* aParent,
     SetIcon( icon );
 
     // Create GAL canvas
+    if( aBackend == EDA_DRAW_PANEL_GAL::GAL_TYPE_UNKNOWN )
+        m_canvasType = LoadCanvasTypeSetting();
+    else
+        m_canvasType = aBackend;
+
     PCB_DRAW_PANEL_GAL* drawPanel = new PCB_DRAW_PANEL_GAL( this, -1, wxPoint( 0, 0 ), m_FrameSize,
-                                                            GetGalDisplayOptions(), aBackend );
+                                                            GetGalDisplayOptions(), m_canvasType );
     SetGalCanvas( drawPanel );
 
     SetBoard( new BOARD() );
@@ -317,7 +322,7 @@ FOOTPRINT_EDIT_FRAME::FOOTPRINT_EDIT_FRAME( KIWAY* aKiway, wxWindow* aParent,
     // Create the manager and dispatcher & route draw panel events to the dispatcher
     setupTools();
     GetGalCanvas()->GetGAL()->SetAxesEnabled( true );
-    UseGalCanvas( aBackend != EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE );
+    UseGalCanvas( m_canvasType != EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE );
 
     m_auimgr.Update();
     updateTitle();

pcbnew/pcb_base_frame.cpp

@@ -61,7 +61,6 @@
 #include <tool/tool_dispatcher.h>
 #include <tools/pcb_actions.h>
 
-const wxChar PCB_BASE_FRAME::CANVAS_TYPE_KEY[] = wxT( "canvas_type" );
 const wxChar PCB_BASE_FRAME::AUTO_ZOOM_KEY[] = wxT( "AutoZoom" );
 const wxChar PCB_BASE_FRAME::ZOOM_KEY[] = wxT( "Zoom" );
 
@@ -126,6 +125,12 @@ PCB_BASE_FRAME::PCB_BASE_FRAME( KIWAY* aKiway, wxWindow* aParent, FRAME_T aFrame
 
 PCB_BASE_FRAME::~PCB_BASE_FRAME()
 {
+    // Ensure m_canvasType is up to date, to save it in config
+    if( !GetGalCanvas() )
+        m_canvasType = EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE;
+    else
+        m_canvasType = GetGalCanvas()->GetBackend();
+
     delete m_Collector;
     delete m_Pcb;
 }

pcbnew/pcb_edit_frame.cpp

@@ -390,12 +390,12 @@ PCB_EDIT_FRAME::PCB_EDIT_FRAME( KIWAY* aKiway, wxWindow* aParent ) :
 
     Zoom_Automatique( false );
 
-    EDA_DRAW_PANEL_GAL::GAL_TYPE canvasType = LoadCanvasTypeSetting();
+    m_canvasType = LoadCanvasTypeSetting();
 
     // Nudge user to switch to OpenGL if they are on legacy or Cairo
     if( m_firstRunDialogSetting < 1 )
     {
-        if( canvasType != EDA_DRAW_PANEL_GAL::GAL_TYPE_OPENGL )
+        if( m_canvasType != EDA_DRAW_PANEL_GAL::GAL_TYPE_OPENGL )
         {
             wxString msg = _( "KiCad can use your graphics card to give you a smoother "
                               "and faster experience. This option is turned off by "
@@ -439,9 +439,9 @@ PCB_EDIT_FRAME::PCB_EDIT_FRAME( KIWAY* aKiway, wxWindow* aParent ) :
     }
     else
     {
-        if( canvasType != EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE )
+        if( m_canvasType != EDA_DRAW_PANEL_GAL::GAL_TYPE_NONE )
         {
-            if( GetGalCanvas()->SwitchBackend( canvasType ) )
+            if( GetGalCanvas()->SwitchBackend( m_canvasType ) )
                 UseGalCanvas( true );
         }
     }

pcbnew/pcbnew.cpp

@@ -131,18 +131,10 @@ static struct IFACE : public KIFACE_I
         case FRAME_PCB_MODULE_VIEWER:
         case FRAME_PCB_MODULE_VIEWER_MODAL:
         {
-            EDA_DRAW_PANEL_GAL::GAL_TYPE backend;
-            auto pcbFrame = static_cast<PCB_EDIT_FRAME*>( wxWindow::FindWindowByName( wxT( "Pcbnew"  ) ) );
-
-            if( pcbFrame )
-                backend = pcbFrame->GetGalCanvas()->GetBackend();
-            else
-                backend = EDA_DRAW_FRAME::LoadCanvasTypeSetting();
-
             switch( aClassId )
             {
             case FRAME_PCB_MODULE_EDITOR:
-                return new FOOTPRINT_EDIT_FRAME( aKiway, aParent, backend );
+                return new FOOTPRINT_EDIT_FRAME( aKiway, aParent, EDA_DRAW_PANEL_GAL::GAL_TYPE_UNKNOWN );
             case FRAME_PCB_MODULE_VIEWER:
             case FRAME_PCB_MODULE_VIEWER_MODAL:
                 return new FOOTPRINT_VIEWER_FRAME( aKiway, aParent, FRAME_T( aClassId ) );