Gerbview: Fix outdated warning message about missing D-Codes and old RS274D files.

RS274X Gerber files using only regions (polygons) can be valid, and are not old RS274D files
Now a warning is raised only if there are some missing D codes definitions
(RS274D file or broken RS274X file)

Remove unused var and add comments

Fixes: lp:1850821
https://bugs.launchpad.net/kicad/+bug/1850821

common/gbr_metadata.cpp

@@ -336,10 +336,11 @@ int char2Hex( unsigned aCode )
 wxString FormatStringFromGerber( const wxString& aString )
 {
     // make the inverse conversion of FormatStringToGerber()
-    // It converts a "normalized" gerber string and convert it to a 16 bits sequence unicode
+    // It converts a "normalized" gerber string containing escape sequences
+    // and convert it to a 16 bits unicode char
     // and return a wxString (unicode 16) from the gerber string
+    // Note the initial gerber string can already contain unicode chars.
     wxString txt;           // The string converted from Gerber string
-    wxString uniString;     // the unicode string from UTF8 Gerber string but without converted escape sequence
 
     unsigned count = aString.Length();
 

gerbview/gerber_file_image.cpp

@@ -202,8 +202,9 @@ void GERBER_FILE_IMAGE::ResetDefaultValues()
     m_MirrorB  = false;                             // true: miror / axe B (default = Y)
     m_SwapAxis = false;                             // false if A = X, B = Y; true if A =Y, B = Y
     m_Has_DCode = false;                            // true = DCodes in file
-                                                    // false = no DCode->
+                                                    // false = no DCode-> perhaps deprecated RS274D file
-                                                    // search for separate DCode file
+    m_Has_MissingDCode = false;                     // true = some D_Codes are used, but not defined
+                                                    // perhaps deprecated RS274D file
     m_FmtScale.x = m_FmtScale.y = 4;                // Initialize default format to 3.4 => 4
     m_FmtLen.x   = m_FmtLen.y = 3 + 4;              // Initialize default format len = 3+4
 

gerbview/gerber_file_image.h

@@ -162,7 +162,9 @@ public:
 
     int                m_Selected_Tool;                         // For highlight: current selected Dcode
     bool               m_Has_DCode;                             // true = DCodes in file
-                                                                // (false = no DCode -> separate DCode file
+                                                                // false = no DCode -> perhaps deprecated RS274D file
+    bool               m_Has_MissingDCode;                      // true = some DCodes in file are not defined
+                                                                // (broken file or deprecated RS274D file)
     bool               m_360Arc_enbl;                           // Enbl 360 deg circular interpolation
     bool               m_PolygonFillMode;                       // Enable polygon mode (read coord as a polygon descr)
     int                m_PolygonFillModeState;                  // In polygon mode: 0 = first segm, 1 = next segm

gerbview/readgerb.cpp

@@ -74,14 +74,20 @@ bool GERBVIEW_FRAME::Read_GERBER_File( const wxString& GERBER_FullFileName )
         dlg.ShowModal();
     }
 
-    /* if the gerber file is only a RS274D file
+    /* if the gerber file has items using D codes but missing D codes definitions,
-     * (i.e. without any aperture information, but with items), warn the user:
+     * it can be a deprecated RS274D file (i.e. without any aperture information),
+     * or has missing definitions,
+     * warn the user:
      */
-    if( !gerber->m_Has_DCode && gerber->GetItemsList() )
+    if( gerber->GetItemsList() && gerber->m_Has_MissingDCode )
     {
-        msg = _("Warning: this file has no D-Code definition\n"
+        if( !gerber->m_Has_DCode )
-                "It is perhaps an old RS274D file\n"
+            msg = _("Warning: this file has no D-Code definition\n"
-                "Therefore the size of items is undefined");
+                    "Therefore the size of some items is undefined");
+        else
+            msg = _("Warning: this file has some missing D-Code definitions\n"
+                    "Therefore the size of some items is undefined");
+
         wxMessageBox( msg );
     }
 

gerbview/rs274d.cpp

@@ -505,14 +505,17 @@ bool GERBER_FILE_IMAGE::Execute_G_Command( char*& text, int G_command )
     case GC_SELECT_TOOL:
     {
         int D_commande = DCodeNumber( text );
+
         if( D_commande < FIRST_DCODE )
             return false;
         if( D_commande > (TOOLS_MAX_COUNT - 1) )
             D_commande = TOOLS_MAX_COUNT - 1;
         m_Current_Tool = D_commande;
         D_CODE* pt_Dcode = GetDCODE( D_commande );
+
         if( pt_Dcode )
             pt_Dcode->m_InUse = true;
+
         break;
     }
 
@@ -597,8 +600,11 @@ bool GERBER_FILE_IMAGE::Execute_DCODE_Command( char*& text, int D_commande )
         m_Current_Tool = D_commande;
 
         D_CODE* pt_Dcode = GetDCODE( D_commande );
+
         if( pt_Dcode )
             pt_Dcode->m_InUse = true;
+        else
+            m_Has_MissingDCode = true;
 
         return true;
     }