wxGTK: Fixed printing to use fonts sizes adjustment consistent with wxMSW. In

particular, screen resolution no longer affects text size in printed output
when using wx's map-screen-to-paper approach to printing.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@55928 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/dc.h

@@ -562,6 +562,10 @@ protected:
                                   double sa, double ea );
 #endif // __WXWINCE__
 
+    // returns adjustment factor for converting wxFont "point size"; in wx
+    // it is point size on screen and needs to be multiplied by this value
+    // for rendering on higher-resolution DCs such as printer ones
+    static float GetFontPointSizeAdjustment(float dpi);
 
     // window on which the DC draws or NULL
     wxWindow   *m_window;

src/common/dcbase.cpp

@@ -1648,3 +1648,15 @@ void wxDCImpl::CalculateEllipticPoints( wxPointList* points,
 } // CalculateEllipticPoints
 
 #endif // __WXWINCE__
+
+float wxDCImpl::GetFontPointSizeAdjustment(float dpi)
+{
+    // wxMSW has long-standing bug where wxFont point size is interpreted as
+    // "pixel size corresponding to given point size *on screen*". In other
+    // words, on a typical 600dpi printer and a typical 96dpi screen, fonts
+    // are ~6 times smaller when printing. Unfortunately, this bug is so severe
+    // that *all* printing code has to account for it and consequently, other
+    // ports need to emulate this bug too:
+    const wxSize screenPPI = wxGetDisplayPPI();
+    return float(screenPPI.y) / dpi;
+}

src/generic/dcpsg.cpp

@@ -1121,9 +1121,10 @@ void wxPostScriptDCImpl::SetFont( const wxFont& font )
     PsPrint( " findfont\n" );
 
 
-    double size = (double) m_font.GetPointSize();
+    float size = float(m_font.GetPointSize());
+    size = size * GetFontPointSizeAdjustment(DPI);
     wxString buffer;
-    buffer.Printf( "%f scalefont setfont\n", size * DEV2PS * m_scaleX );
+    buffer.Printf( "%f scalefont setfont\n", size * m_scaleX );
     buffer.Replace( ",", "." );
     PsPrint( buffer );
 }
@@ -1998,7 +1999,8 @@ void wxPostScriptDCImpl::DoGetTextExtent(const wxString& string,
 
     if (!fontToUse) fontToUse = &m_font;
 
-    wxCHECK_RET( fontToUse, wxT("GetTextExtent: no font defined") );
+    const float fontSize =
+        fontToUse->GetPointSize() * GetFontPointSizeAdjustment(72.0);
 
     if (string.empty())
     {
@@ -2022,15 +2024,10 @@ void wxPostScriptDCImpl::DoGetTextExtent(const wxString& string,
      * Produces accurate results for mono-spaced font
      * such as Courier (aka wxMODERN) */
 
-    int height = 12;
-    if (fontToUse)
-    {
-        height = fontToUse->GetPointSize();
-    }
     if ( x )
-        *x = strlen (strbuf) * height * 72 / 120;
+        *x = strlen (strbuf) * fontSize * 72.0 / 120.0;
     if ( y )
-        *y = (wxCoord) (height * 1.32);    /* allow for descender */
+        *y = (wxCoord) (fontSize * 1.32);    /* allow for descender */
     if (descent) *descent = 0;
     if (externalLeading) *externalLeading = 0;
 #else
@@ -2297,9 +2294,9 @@ void wxPostScriptDCImpl::DoGetTextExtent(const wxString& string,
         // VS: dirty, but is there any better solution?
         double *pt;
         pt = (double*) &m_underlinePosition;
-        *pt = YLOG2DEVREL((wxCoord)(UnderlinePosition * fontToUse->GetPointSize())) / 1000.0f;
+        *pt = YLOG2DEVREL((wxCoord)(UnderlinePosition * fontSize)) / 1000.0f;
         pt = (double*) &m_underlineThickness;
-        *pt = YLOG2DEVREL((wxCoord)(UnderlineThickness * fontToUse->GetPointSize())) / 1000.0f;
+        *pt = YLOG2DEVREL((wxCoord)(UnderlineThickness * fontSize)) / 1000.0f;
 
     }
 
@@ -2309,7 +2306,7 @@ void wxPostScriptDCImpl::DoGetTextExtent(const wxString& string,
        /  string. they are given in 1/1000 of the size! */
 
     long sum=0;
-    wxCoord height=Size; /* by default */
+    float height=fontSize; /* by default */
     unsigned char *p;
     for(p=(unsigned char *)wxMBSTRINGCAST strbuf; *p; p++)
     {
@@ -2325,7 +2322,7 @@ void wxPostScriptDCImpl::DoGetTextExtent(const wxString& string,
     }
 
     double widthSum = sum;
-    widthSum *= Size;
+    widthSum *= fontSize;
     widthSum /= 1000.0F;
 
     /* add descender to height (it is usually a negative value) */
@@ -2340,14 +2337,14 @@ void wxPostScriptDCImpl::DoGetTextExtent(const wxString& string,
     if ( x )
         *x = (wxCoord)widthSum;
     if ( y )
-        *y = height;
+        *y = (wxCoord)height;
 
     /* return other parameters */
     if (descent)
     {
         if(lastDescender!=INT_MIN)
         {
-            *descent = (wxCoord)(((-lastDescender)/1000.0F) * Size); /* MATTHEW: forgot scale */
+            *descent = (wxCoord)(((-lastDescender)/1000.0F) * fontSize); /* MATTHEW: forgot scale */
         }
         else
         {

src/gtk/gnome/gprint.cpp

@@ -1638,8 +1638,6 @@ void wxGnomePrinterDCImpl::DoDrawRotatedText(const wxString& text, wxCoord x, wx
         }
     }
 
-    int w,h;
-    pango_layout_get_pixel_size( m_layout, &w, &h );
 #if 0
         if ( m_backgroundMode == wxSOLID )
         {
@@ -1661,6 +1659,9 @@ void wxGnomePrinterDCImpl::DoDrawRotatedText(const wxString& text, wxCoord x, wx
 
     gs_libGnomePrint->gnome_print_pango_layout( m_gpc, m_layout );
 
+    int w,h;
+    pango_layout_get_pixel_size( m_layout, &w, &h );
+
     gs_libGnomePrint->gnome_print_grestore( m_gpc );
 
     if (underlined)
@@ -1669,7 +1670,8 @@ void wxGnomePrinterDCImpl::DoDrawRotatedText(const wxString& text, wxCoord x, wx
         pango_layout_set_attributes(m_layout, NULL);
     }
 
-    CalcBoundingBox (x + w, y + h);
+    CalcBoundingBox(x, y);
+    CalcBoundingBox(x + w, y + h);
 }
 
 void wxGnomePrinterDCImpl::Clear()
@@ -1687,6 +1689,10 @@ void wxGnomePrinterDCImpl::SetFont( const wxFont& font )
 
         m_fontdesc = pango_font_description_copy( m_font.GetNativeFontInfo()->description );
 
+        float size = pango_font_description_get_size( m_fontdesc );
+        size = size * GetFontPointSizeAdjustment(72.0);
+        pango_font_description_set_size( m_fontdesc, (gint)size );
+
         pango_layout_set_font_description( m_layout, m_fontdesc );
     }
 }
@@ -1914,26 +1920,24 @@ void wxGnomePrinterDCImpl::DoGetTextExtent(const wxString& string, wxCoord *widt
     const wxCharBuffer dataUTF8 = string.utf8_str();
 #endif
 
-    PangoFontDescription *desc = (theFont) ? theFont->GetNativeFontInfo()->description : m_fontdesc;
+    gint oldSize;
+    if ( theFont )
+    {
+        // scale the font and apply it
+        PangoFontDescription *desc = theFont->GetNativeFontInfo()->description;
+        float size = pango_font_description_get_size(desc);
+        size = size * GetFontPointSizeAdjustment(72.0);
+        pango_font_description_set_size(desc, (gint)size);
 
-    gint oldSize = pango_font_description_get_size( desc );
+        pango_layout_set_font_description(m_layout, desc);
-    double size = oldSize;
+    }
-    size = size * m_scaleY;
-    pango_font_description_set_size( desc, (gint)size );
-
-    // apply scaled font
-    pango_layout_set_font_description( m_layout, desc );
 
     pango_layout_set_text( m_layout, dataUTF8, strlen(dataUTF8) );
 
-    int w, h;
+    int h;
-    pango_layout_get_pixel_size( m_layout, &w, &h );
+    pango_layout_get_pixel_size( m_layout, width, &h );
-
+    if ( height )
-
+        *height = h;
-    if (width)
-        *width = (wxCoord)(w / m_scaleX);
-    if (height)
-        *height = (wxCoord)(h / m_scaleY);
 
     if (descent)
     {
@@ -1943,11 +1947,14 @@ void wxGnomePrinterDCImpl::DoGetTextExtent(const wxString& string, wxCoord *widt
         *descent = h - PANGO_PIXELS(baseline);
     }
 
-    // reset unscaled size
+    if ( theFont )
-    pango_font_description_set_size( desc, oldSize );
+    {
+        // restore font and reset font's size back
+        pango_layout_set_font_description(m_layout, m_fontdesc);
 
-    // reset unscaled font
+        PangoFontDescription *desc = theFont->GetNativeFontInfo()->description;
-    pango_layout_set_font_description( m_layout, m_fontdesc );
+        pango_font_description_set_size(desc, oldSize);
+    }
 }
 
 void wxGnomePrinterDCImpl::DoGetSize(int* width, int* height) const

src/gtk/print.cpp

@@ -1814,17 +1814,17 @@ void wxGtkPrinterDCImpl::DoDrawRotatedText(const wxString& text, wxCoord x, wxCo
         }
     }
 
+    // Draw layout.
+    cairo_move_to (m_cairo, xx, yy);
+
+    cairo_save( m_cairo );
+
+    if (fabs(angle) > 0.00001)
+        cairo_rotate( m_cairo, angle*DEG2RAD );
+
+    cairo_scale(m_cairo, m_scaleX, m_scaleY);
+
     int w,h;
-
-    // Scale font description.
-    gint oldSize = pango_font_description_get_size( m_fontdesc );
-    double size = oldSize;
-    size = size * m_scaleX;
-    pango_font_description_set_size( m_fontdesc, (gint)size );
-
-    // Actually apply scaled font.
-    pango_layout_set_font_description( m_layout, m_fontdesc );
-
     pango_layout_get_pixel_size( m_layout, &w, &h );
 
     if ( m_backgroundMode == wxBRUSHSTYLE_SOLID )
@@ -1840,22 +1840,12 @@ void wxGtkPrinterDCImpl::DoDrawRotatedText(const wxString& text, wxCoord x, wxCo
         double alphaPS = (double)(alpha) / 255.0;
 
         cairo_save(m_cairo);
-            cairo_translate(m_cairo, xx, yy);
         cairo_set_source_rgba( m_cairo, redPS, greenPS, bluePS, alphaPS );
-            cairo_rotate(m_cairo,angle*DEG2RAD);
         cairo_rectangle(m_cairo, 0, 0, w, h);   // still in cairo units
         cairo_fill(m_cairo);
         cairo_restore(m_cairo);
     }
 
-    // Draw layout.
-    cairo_move_to (m_cairo, xx, yy);
-
-    cairo_save( m_cairo );
-
-    if (fabs(angle) > 0.00001)
-        cairo_rotate( m_cairo, angle*DEG2RAD );
-
     pango_cairo_update_layout (m_cairo, m_layout);
     pango_cairo_show_layout (m_cairo, m_layout);
 
@@ -1867,12 +1857,6 @@ void wxGtkPrinterDCImpl::DoDrawRotatedText(const wxString& text, wxCoord x, wxCo
         pango_layout_set_attributes(m_layout, NULL);
     }
 
-    // Reset unscaled size.
-    pango_font_description_set_size( m_fontdesc, oldSize );
-
-    // Actually apply unscaled font.
-    pango_layout_set_font_description( m_layout, m_fontdesc );
-
     // Back to device units:
     CalcBoundingBox (x, y);
     CalcBoundingBox (x + w, y + h);
@@ -1902,6 +1886,10 @@ void wxGtkPrinterDCImpl::SetFont( const wxFont& font )
 
         m_fontdesc = pango_font_description_copy( m_font.GetNativeFontInfo()->description );
 
+        float size = pango_font_description_get_size( m_fontdesc );
+        size = size * GetFontPointSizeAdjustment(72.0);
+        pango_font_description_set_size( m_fontdesc, (gint)size );
+
         pango_layout_set_font_description( m_layout, m_fontdesc );
     }
 }
@@ -2185,43 +2173,49 @@ void wxGtkPrinterDCImpl::DoGetTextExtent(const wxString& string, wxCoord *width,
         return;
     }
 
+    cairo_save( m_cairo );
+    cairo_scale(m_cairo, m_scaleX, m_scaleY);
+
     // Set layout's text
     const wxUTF8Buf dataUTF8 = string.utf8_str();
 
-    PangoFontDescription *desc = m_fontdesc;
+    gint oldSize;
-    if (theFont) desc = theFont->GetNativeFontInfo()->description;
+    if ( theFont )
+    {
+        // scale the font and apply it
+        PangoFontDescription *desc = theFont->GetNativeFontInfo()->description;
+        float size = pango_font_description_get_size(desc);
+        size = size * GetFontPointSizeAdjustment(72.0);
+        pango_font_description_set_size(desc, (gint)size);
 
-    gint oldSize = pango_font_description_get_size( desc );
+        pango_layout_set_font_description(m_layout, desc);
-    double size = oldSize;
+    }
-    size = size * m_scaleY;
-    pango_font_description_set_size( desc, (gint)size );
-
-    // apply scaled font
-    pango_layout_set_font_description( m_layout, desc );
 
     pango_layout_set_text( m_layout, dataUTF8, strlen(dataUTF8) );
 
-    int w, h;
+    int h;
-    pango_layout_get_pixel_size( m_layout, &w, &h );
+    pango_layout_get_pixel_size( m_layout, width, &h );
-
+    if ( height )
-    if (width)
+        *height = h;
-        *width = wxRound( (double)w / m_scaleX * m_PS2DEV );
-    if (height)
-        *height = wxRound( (double)h / m_scaleY * m_PS2DEV );
 
     if (descent)
     {
         PangoLayoutIter *iter = pango_layout_get_iter(m_layout);
         int baseline = pango_layout_iter_get_baseline(iter);
         pango_layout_iter_free(iter);
-        *descent = wxRound( (h - PANGO_PIXELS(baseline)) * m_PS2DEV );
+        *descent = h - PANGO_PIXELS(baseline);
     }
 
-    // Reset unscaled size.
+    if ( theFont )
-    pango_font_description_set_size( desc, oldSize );
+    {
+        // restore font and reset font's size back
+        pango_layout_set_font_description(m_layout, m_fontdesc);
 
-    // Reset unscaled font.
+        PangoFontDescription *desc = theFont->GetNativeFontInfo()->description;
-    pango_layout_set_font_description( m_layout, m_fontdesc );
+        pango_font_description_set_size(desc, oldSize);
+    }
+
+    cairo_restore( m_cairo );
 }
 
 void wxGtkPrinterDCImpl::DoGetSize(int* width, int* height) const