PDF plotter: better handling of non ASCII7 (unicode 16) chars.

Note also the PS plotter handle poorly these non ASCII chars.

Fixes #4957
https://gitlab.com/kicad/code/kicad/issues/4957

common/plotters/PDF_plotter.cpp

@@ -41,6 +41,70 @@
 #include <algorithm>
 
 
+std::string PDF_PLOTTER::encodeStringForPlotter( const wxString& aText )
+{
+// returns a string compatible with PDF string convention from a unicode string.
+// if the initial text is only ASCII7, return the text between ( and ) for a good readability
+// if the initial text is no ASCII7, return the text between < and >
+// and encoded using 16 bits hexa (4 digits) by wide char (unicode 16)
+    std::string result;
+
+    // Is aText only ASCII7 ?
+    bool is_ascii7 = true;
+
+    for( size_t ii = 0; ii < aText.Len(); ii++ )
+    {
+        if( aText[ii] >= 0x7F )
+        {
+            is_ascii7 = false;
+            break;
+        }
+    }
+
+    if( is_ascii7 )
+    {
+        result = '(';
+
+        for( unsigned ii = 0; ii < aText.Len(); ii++ )
+        {
+            unsigned int code = aText[ii];
+
+            // These characters must be escaped
+            switch( code )
+            {
+            // se if '(' and ')' must be escaped.
+            case '\\':
+                result += '\\';
+                KI_FALLTHROUGH;
+
+            default:
+                result += code;
+                break;
+            }
+        }
+
+        result += ')';
+    }
+    else
+    {
+        result = "<FEFF";
+
+        for( size_t ii = 0; ii < aText.Len(); ii++ )
+        {
+            unsigned int code = aText[ii];
+            char buffer[16];
+            sprintf( buffer, "%4.4X", code );
+            result += buffer;
+
+        }
+
+        result += '>';
+    }
+
+    return result;
+}
+
+
 /*
  * Open or create the plot file aFullFilename
  * return true if success, false if the file cannot be created/opened
@@ -749,14 +813,14 @@ bool PDF_PLOTTER::EndPlot()
 
     fprintf( outputFile,
              "<<\n"
-             "/Producer (KiCAD PDF)\n"
+             "/Producer (KiCad PDF)\n"
              "/CreationDate (%s)\n"
-             "/Creator (%s)\n"
-             "/Title (%s)\n"
+             "/Creator %s\n"
+             "/Title %s\n"
              "/Trapped False\n",
              date_buf,
-             TO_UTF8( creator ),
-             TO_UTF8( title ) );
+             encodeStringForPlotter( creator ).c_str(),
+             encodeStringForPlotter( title ).c_str() );
 
     fputs( ">>\n", outputFile );
     closePdfObject();
@@ -846,8 +910,8 @@ void PDF_PLOTTER::Text( const wxPoint&              aPos,
              fontname, heightFactor, render_mode, wideningFactor * 100 );
 
     // The text must be escaped correctly
-    fputsPostscriptString( workFile, aText );
-    fputs( " Tj ET\n", workFile );
+    std:: string txt_pdf = encodeStringForPlotter( aText );
+    fprintf( workFile, "%s Tj ET\n", txt_pdf.c_str() );
 
     // Restore the CTM
     fputs( "Q\n", workFile );

common/plotters/PS_plotter.cpp

@@ -300,16 +300,17 @@ void PSLIKE_PLOTTER::FlashRegularPolygon( const wxPoint& aShapePos,
 }
 
 
-/**
- * Write on a stream a string escaped for postscript/PDF
- */
-void PSLIKE_PLOTTER::fputsPostscriptString(FILE *fout, const wxString& txt)
+std::string PSLIKE_PLOTTER::encodeStringForPlotter( const wxString& aUnicode )
 {
-    putc( '(', fout );
-    for( unsigned i = 0; i < txt.length(); i++ )
+    // Write on a std::string a string escaped for postscript/PDF
+    std::string converted;
+
+    converted += '(';
+
+    for( unsigned i = 0; i < aUnicode.Len(); i++ )
     {
         // Lazyness made me use stdio buffering yet another time...
-        wchar_t ch = txt[i];
+        wchar_t ch = aUnicode[i];
 
         if( ch < 256 )
         {
@@ -322,17 +323,19 @@ void PSLIKE_PLOTTER::fputsPostscriptString(FILE *fout, const wxString& txt)
             case '(':
             case ')':
             case '\\':
-                putc( '\\', fout );
+                converted += '\\';
                 KI_FALLTHROUGH;
 
             default:
-                putc( ch, fout );
+                converted += ch;
                 break;
             }
         }
     }
 
-    putc( ')', fout );
+    converted += ')';
+
+    return converted;
 }
 
 
@@ -871,7 +874,7 @@ bool PS_PLOTTER::StartPlot()
     /* A "newline" character ("\n") is not included in the following string,
        because it is provided by the ctime() function. */
     fprintf( outputFile, "%%%%CreationDate: %s", ctime( &time1970 ) );
-    fprintf( outputFile, "%%%%Title: %s\n", TO_UTF8( filename ) );
+    fprintf( outputFile, "%%%%Title: %s\n", encodeStringForPlotter( title ).c_str() );
     fprintf( outputFile, "%%%%Pages: 1\n" );
     fprintf( outputFile, "%%%%PageOrder: Ascend\n" );
 
@@ -991,9 +994,9 @@ void PS_PLOTTER::Text( const wxPoint&       aPos,
     // Draw the hidden postscript text (if requested)
     if( m_textMode == PLOT_TEXT_MODE::PHANTOM )
     {
-        fputsPostscriptString( outputFile, aText );
+        std::string ps_test = encodeStringForPlotter( aText );
         DPOINT pos_dev = userToDeviceCoordinates( aPos );
-        fprintf( outputFile, " %g %g phantomshow\n", pos_dev.x, pos_dev.y );
+        fprintf( outputFile, "%s %g %g phantomshow\n", ps_test.c_str(), pos_dev.x, pos_dev.y );
     }
 
     PLOTTER::Text( aPos, aColor, aText, aOrient, aSize, aH_justify, aV_justify, aWidth,

include/plotter.h

@@ -766,7 +766,10 @@ protected:
     void postscriptOverlinePositions( const wxString& aText, int aXSize,
                                       bool aItalic, bool aBold,
                                       std::vector<int> *pos_pairs );
-    void fputsPostscriptString(FILE *fout, const wxString& txt);
+
+    /// convert a wxString unicode string to a char string compatible with the accepted
+    /// string plotter format (convert special chars and non ascii7 chars)
+    virtual std::string encodeStringForPlotter( const wxString& aUnicode );
 
     /// Virtual primitive for emitting the setrgbcolor operator
     virtual void emitSetRGBColor( double r, double g, double b ) = 0;
@@ -917,6 +920,10 @@ public:
 
 
 protected:
+    /// convert a wxString unicode string to a char string compatible with the accepted
+    /// string PDF format (convert special chars and non ascii7 chars)
+    std::string encodeStringForPlotter( const wxString& aUnicode ) override;
+
     virtual void emitSetRGBColor( double r, double g, double b ) override;
     int allocPdfObject();
     int startPdfObject(int handle = -1);