X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/aae0472bf3086707216125e4caa8650caeeeaf97..a83ea9c15a7ac7bbdc6686164cfcbbc21ae5031a:/src/motif/dcclient.cpp

diff --git a/src/motif/dcclient.cpp b/src/motif/dcclient.cpp
index 3459154e7f..908526c8bc 100644
--- a/src/motif/dcclient.cpp
+++ b/src/motif/dcclient.cpp
@@ -36,10 +36,13 @@
 // headers
 // ----------------------------------------------------------------------------
 
-#ifdef __GNUG__
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
     #pragma implementation "dcclient.h"
 #endif
 
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
 #include "wx/dcclient.h"
 #include "wx/dcmemory.h"
 #include "wx/window.h"
@@ -83,9 +86,15 @@ static Pixmap bdiag, cdiag, fdiag, cross, horiz, verti;
 // macros
 // ----------------------------------------------------------------------------
 
-    IMPLEMENT_DYNAMIC_CLASS(wxClientDC, wxWindowDC)
-    IMPLEMENT_DYNAMIC_CLASS(wxPaintDC, wxWindowDC)
-    IMPLEMENT_DYNAMIC_CLASS(wxWindowDC, wxDC)
+IMPLEMENT_DYNAMIC_CLASS(wxClientDC, wxWindowDC)
+IMPLEMENT_DYNAMIC_CLASS(wxPaintDC, wxWindowDC)
+IMPLEMENT_DYNAMIC_CLASS(wxWindowDC, wxDC)
+
+#ifndef IS_HATCH
+    // IS_HATCH exists for WXWIN_COMPATIBILITY_2_4 only
+    // but wxMotif needs it for its internals here
+    #define IS_HATCH(s)    ((s)>=wxBDIAGONAL_HATCH && (s)<=wxVERTICAL_HATCH)
+#endif
 
 // ----------------------------------------------------------------------------
 // prototypes
@@ -126,7 +135,7 @@ static int roundmin(double a, double b)
 // wxWindowDC
 // ----------------------------------------------------------------------------
 
-wxWindowDC::wxWindowDC()
+void wxWindowDC::Init()
 {
     m_gc = (WXGC) 0;
     m_gcBacking = (WXGC) 0;
@@ -138,37 +147,29 @@ wxWindowDC::wxWindowDC()
     m_currentPenDash = (wxX11Dash*) NULL;
     m_currentStyle = -1;
     m_currentFill = -1;
-    //    m_currentBkMode = wxTRANSPARENT;
     m_colour = wxColourDisplay();
     m_display = (WXDisplay*) NULL;
-    m_currentRegion = (WXRegion) 0;
-    m_userRegion = (WXRegion) 0;
     m_pixmap = (WXPixmap) 0;
     m_autoSetting = 0;
     m_oldFont = (WXFont) 0;
+    m_ok = false;
+    m_clipRegion = (WXRegion) 0;
+}
+
+wxWindowDC::wxWindowDC()
+{
+    Init();
 }
 
 wxWindowDC::wxWindowDC( wxWindow *window )
 {
     wxASSERT_MSG( (window != (wxWindow*) NULL), "You must pass a valid wxWindow to wxWindowDC/wxClientDC/wxPaintDC constructor." );
 
+    Init();
+
     m_window = window;
     m_font = window->GetFont();
-    m_gc = (WXGC) 0;
-    m_gcBacking = (WXGC) 0;
-    m_backgroundPixel = -1;
-    m_currentPenWidth = 1;
-    m_currentPenJoin = -1;
-    m_currentPenDashCount = -1;
-    m_currentPenDash = (wxX11Dash*) NULL;
-    m_currentStyle = -1;
-    m_currentFill = -1;
-    //    m_currentBkMode = wxTRANSPARENT;
-    m_colour = wxColourDisplay();
-    m_currentRegion = (WXRegion) 0;
-    m_userRegion = (WXRegion) 0;
-    m_ok = TRUE;
-    m_autoSetting = 0;
+    m_ok = true;
 
     m_display = window->GetXDisplay();
     m_pixmap = window->GetXWindow();
@@ -222,16 +223,12 @@ wxWindowDC::~wxWindowDC()
         XFreeGC ((Display*) m_display, (GC) m_gcBacking);
     m_gcBacking = (WXGC) 0;
 
-    if (m_currentRegion)
-        XDestroyRegion ((Region) m_currentRegion);
-    m_currentRegion = (WXRegion) 0;
-
-    if (m_userRegion)
-        XDestroyRegion ((Region) m_userRegion);
-    m_userRegion = (WXRegion) 0;
+    if (m_clipRegion)
+        XDestroyRegion ((Region) m_clipRegion);
+    m_clipRegion = (WXRegion) 0;
 }
 
-extern bool wxDoFloodFill(wxDC *dc, wxCoord x, wxCoord y, 
+extern bool wxDoFloodFill(wxDC *dc, wxCoord x, wxCoord y,
                           const wxColour & col, int style);
 
 bool wxWindowDC::DoFloodFill(wxCoord x, wxCoord y,
@@ -239,7 +236,7 @@ bool wxWindowDC::DoFloodFill(wxCoord x, wxCoord y,
 {
     return wxDoFloodFill(this, x, y, col, style);
 }
-  
+
 bool wxWindowDC::DoGetPixel( wxCoord x1, wxCoord y1, wxColour *col ) const
 {
     // Generic (and therefore rather inefficient) method.
@@ -251,7 +248,7 @@ bool wxWindowDC::DoGetPixel( wxCoord x1, wxCoord y1, wxColour *col ) const
     memdc.SelectObject(wxNullBitmap);
     wxImage image = bitmap.ConvertToImage();
     col->Set(image.GetRed(0, 0), image.GetGreen(0, 0), image.GetBlue(0, 0));
-    return TRUE;
+    return true;
 }
 
 void wxWindowDC::DoDrawLine( wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2 )
@@ -260,8 +257,6 @@ void wxWindowDC::DoDrawLine( wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2 )
 
     int x1d, y1d, x2d, y2d;
 
-    //  FreeGetPixelCache();
-
     x1d = XLOG2DEV(x1);
     y1d = YLOG2DEV(y1);
     x2d = XLOG2DEV(x2);
@@ -314,8 +309,6 @@ void wxWindowDC::DoDrawArc( wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, wxCo
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    //  FreeGetPixelCache();
-
     int xx1 = XLOG2DEV (x1);
     int yy1 = YLOG2DEV (y1);
     int xx2 = XLOG2DEV (x2);
@@ -442,8 +435,6 @@ void wxWindowDC::DoDrawPoint( wxCoord x, wxCoord y )
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    //  FreeGetPixelCache();
-
     if (m_pen.Ok() && m_autoSetting)
         SetPen (m_pen);
 
@@ -458,8 +449,6 @@ void wxWindowDC::DoDrawLines( int n, wxPoint points[], wxCoord xoffset, wxCoord
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    //  FreeGetPixelCache();
-
     if (m_pen.Ok() && m_pen.GetStyle () != wxTRANSPARENT)
     {
         if (m_autoSetting)
@@ -493,8 +482,6 @@ void wxWindowDC::DoDrawPolygon( int n, wxPoint points[],
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    //  FreeGetPixelCache();
-
     XPoint *xpoints1 = new XPoint[n + 1];
     XPoint *xpoints2 = new XPoint[n + 1];
     int i;
@@ -546,8 +533,6 @@ void wxWindowDC::DoDrawRectangle( wxCoord x, wxCoord y, wxCoord width, wxCoord h
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    //  FreeGetPixelCache();
-
     int xd, yd, wfd, hfd, wd, hd;
 
     xd = XLOG2DEV(x);
@@ -591,8 +576,6 @@ void wxWindowDC::DoDrawRoundedRectangle( wxCoord x, wxCoord y, wxCoord width, wx
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    //  FreeGetPixelCache();
-
     // If radius is negative, it's a proportion of the smaller dimension.
 
     if (radius < 0.0) radius = - radius * ((width < height) ? width : height);
@@ -747,8 +730,6 @@ void wxWindowDC::DoDrawRoundedRectangle( wxCoord x, wxCoord y, wxCoord width, wx
     }
     CalcBoundingBox (x, y);
     CalcBoundingBox (x + width, y + height);
-
-
 }
 
 void wxWindowDC::DoDrawEllipse( wxCoord x, wxCoord y, wxCoord width, wxCoord height )
@@ -768,8 +749,6 @@ void wxWindowDC::DoDrawEllipse( wxCoord x, wxCoord y, wxCoord width, wxCoord hei
         width = - width ;
     }
 
-    //  FreeGetPixelCache();
-
     static const int angle = 23040;
 
     int xd, yd, wd, hd;
@@ -808,84 +787,25 @@ void wxWindowDC::DoDrawEllipse( wxCoord x, wxCoord y, wxCoord width, wxCoord hei
 
 bool wxWindowDC::CanDrawBitmap() const
 {
-    wxCHECK_MSG( Ok(), FALSE, "invalid dc" );
+    wxCHECK_MSG( Ok(), false, "invalid dc" );
 
-    return TRUE;
+    return true;
 }
 
-#if 0
-void wxWindowDC::DoDrawIcon( const wxIcon &icon, wxCoord x, wxCoord y)
-{
-    //  FreeGetPixelCache();
-
-    // Be sure that foreground pixels (1) of
-    // the Icon will be painted with pen colour. [m_pen.SetColour()]
-    // Background pixels (0) will be painted with
-    // last selected background color. [::SetBackground]
-    if (m_pen.Ok() && m_autoSetting)
-        SetPen (m_pen);
-
-    int width, height;
-    Pixmap iconPixmap = (Pixmap) icon.GetDrawable();
-    width = icon.GetWidth();
-    height = icon.GetHeight();
-    if (icon.GetDisplay() == m_display)
-    {
-        if (icon.GetDepth() <= 1)
-        {
-            XCopyPlane  ((Display*) m_display, iconPixmap, (Pixmap) m_pixmap, (GC) m_gc,
-                0, 0, width, height,
-                (int) XLOG2DEV (x), (int) YLOG2DEV (y), 1);
-        }
-        else
-        {
-            XCopyArea  ((Display*) m_display, iconPixmap, (Pixmap) m_pixmap, (GC) m_gc,
-                0, 0, width, height,
-                (int) XLOG2DEV (x), (int) YLOG2DEV (y));
-        }
-
-
-        if (m_window && m_window->GetBackingPixmap())
-        {
-            if (icon.GetDepth() <= 1)
-            {
-                XCopyPlane ((Display*) m_display, iconPixmap, (Pixmap) m_window->GetBackingPixmap(),(GC) m_gcBacking,
-                    0, 0, width, height, (int) XLOG2DEV_2 (x), (int) YLOG2DEV_2 (y), 1);
-            }
-            else
-            {
-                XCopyArea  ((Display*) m_display, iconPixmap, (Pixmap) m_window->GetBackingPixmap(),(GC) m_gcBacking,
-                    0, 0, width, height,
-                    (int) XLOG2DEV_2 (x), (int) YLOG2DEV_2 (y));
-            }
-        }
-    } else { /* Remote copy (different (Display*) m_displays) */
-        XImage *cache = NULL;
-        if (m_window && m_window->GetBackingPixmap())
-            XCopyRemote((Display*) icon.GetDisplay(), (Display*) m_display, iconPixmap, (Pixmap) m_window->GetBackingPixmap(),
-            (GC) m_gcBacking, 0, 0, width, height,
-            (int) XLOG2DEV_2 (x), (int) YLOG2DEV_2 (y), TRUE, &cache);
-        XCopyRemote((Display*) icon.GetDisplay(), (Display*) m_display, iconPixmap, (Pixmap) m_pixmap, (GC) m_gc,
-            0, 0, width, height,
-            (int) XLOG2DEV (x), (int) YLOG2DEV (y), FALSE, &cache);
-    }
-    CalcBoundingBox (x, y);
-}
-#endif // 0
-
-// TODO: use scaled Blit e.g. as per John Price's implementation in Contrib/Utilities
-bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord height,
-                         wxDC *source, wxCoord xsrc, wxCoord ysrc, int rop, bool useMask,
+// TODO: use scaled Blit e.g. as per John Price's implementation
+// in Contrib/Utilities
+bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest,
+                         wxCoord width, wxCoord height,
+                         wxDC *source, wxCoord xsrc, wxCoord ysrc,
+                         int rop, bool useMask,
                          wxCoord xsrcMask, wxCoord ysrcMask )
 {
-    wxCHECK_MSG( Ok(), FALSE, "invalid dc" );
+    wxCHECK_MSG( Ok(), false, "invalid dc" );
 
     wxWindowDC* sourceDC = wxDynamicCast(source, wxWindowDC);
 
     wxASSERT_MSG( sourceDC, "Blit source DC must be wxWindowDC or derived class." );
 
-    //  FreeGetPixelCache();
-
     // Be sure that foreground pixels (1) of the Icon will be painted with
     // foreground colour. [m_textForegroundColour] Background pixels (0)
     // will be painted with backgound colour (m_textBackgroundColour)
@@ -909,8 +829,8 @@ bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord he
 
         if( m_textForegroundColour.GetPixel() <= -1 )
             CalculatePixel( m_textForegroundColour,
-                            m_textForegroundColour, TRUE);
- 
+                            m_textForegroundColour, true);
+
         int pixel = m_textForegroundColour.GetPixel();
         if (pixel > -1)
             SetForegroundPixelWithLogicalFunction(pixel);
@@ -922,7 +842,7 @@ bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord he
     Pixmap sourcePixmap = (Pixmap) NULL;
     double scaleX, scaleY;
     GetUserScale(& scaleX, & scaleY);
-    bool retVal = FALSE;
+    bool retVal = false;
 
     /* TODO: use the mask origin when drawing transparently */
     if (xsrcMask == -1 && ysrcMask == -1)
@@ -999,13 +919,18 @@ bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord he
 
             if ( useMask )
             {
-                XSetClipMask   ((Display*) m_display, (GC) m_gc, None);
+                if ( m_clipRegion )
+                    XSetRegion ((Display*) m_display, (GC) m_gc,
+                                (Region) m_clipRegion);
+                else
+                    XSetClipMask   ((Display*) m_display, (GC) m_gc, None);
+
                 XSetClipOrigin ((Display*) m_display, (GC) m_gc, 0, 0);
             }
 
         } else
         {        //XGCValues values;
-        //XGetGCValues((Display*)m_display, (GC)m_gc, GCForeground, &values);   
+        //XGetGCValues((Display*)m_display, (GC)m_gc, GCForeground, &values);
 
             if (m_window && m_window->GetBackingPixmap())
             {
@@ -1063,7 +988,12 @@ bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord he
             }
             if ( useMask )
             {
-                XSetClipMask   ((Display*) m_display, (GC) m_gc, None);
+                if ( m_clipRegion )
+                    XSetRegion ((Display*) m_display, (GC) m_gc,
+                                (Region) m_clipRegion);
+                else
+                    XSetClipMask   ((Display*) m_display, (GC) m_gc, None);
+
                 XSetClipOrigin ((Display*) m_display, (GC) m_gc, 0, 0);
             }
 
@@ -1073,7 +1003,7 @@ bool wxWindowDC::DoBlit( wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord he
 
         SetLogicalFunction(orig);
 
-        retVal = TRUE;
+        retVal = true;
   }
   if (scaledBitmap) delete scaledBitmap;
 
@@ -1191,7 +1121,7 @@ void wxWindowDC::DoDrawText( const wxString &text, wxCoord x, wxCoord y )
         if (!sameColour || !GetOptimization())
         {
             int pixel = CalculatePixel(m_textForegroundColour,
-                                       m_currentColour, FALSE);
+                                       m_currentColour, false);
 
             // Set the GC to the required colour
             if (pixel > -1)
@@ -1267,8 +1197,8 @@ void wxWindowDC::DoDrawRotatedText( const wxString &text, wxCoord x, wxCoord y,
 
         if( m_textForegroundColour.GetPixel() <= -1 )
             CalculatePixel( m_textForegroundColour,
-                            m_textForegroundColour, TRUE);
- 
+                            m_textForegroundColour, true);
+
         foregroundPixel = m_textForegroundColour.GetPixel();
     }
 
@@ -1399,7 +1329,7 @@ void wxWindowDC::DoDrawRotatedText( const wxString &text, wxCoord x, wxCoord y,
 
 bool wxWindowDC::CanGetTextExtent() const
 {
-    return TRUE;
+    return true;
 }
 
 void wxWindowDC::DoGetTextExtent( const wxString &string, wxCoord *width, wxCoord *height,
@@ -1482,42 +1412,31 @@ wxCoord wxWindowDC::GetCharHeight() const
     return XDEV2LOGREL(ascent + descent);
 }
 
-void wxWindowDC::Clear()
+void wxWindowDC::DoGetSize( int *width, int *height ) const
 {
-    wxCHECK_RET( Ok(), "invalid dc" );
+    int w = 0, h = 0;
 
-    int w, h;
-    if (m_window)
+    if( m_window )
     {
-        m_window->GetSize(&w, &h);
-
-        if (m_window && m_window->GetBackingPixmap())
+        if( m_window->GetBackingPixmap() )
         {
             w = m_window->GetPixmapWidth();
             h = m_window->GetPixmapHeight();
         }
-    }
-    else
-    {
-        if (this->IsKindOf(CLASSINFO(wxMemoryDC)))
-        {
-            wxMemoryDC* memDC = (wxMemoryDC*) this;
-            w = memDC->GetBitmap().GetWidth();
-            h = memDC->GetBitmap().GetHeight();
-        }
         else
-            return;
+            m_window->GetSize( &w, &h );
     }
 
-    wxBrush saveBrush = m_brush;
-    SetBrush (m_backgroundBrush);
-
-    XFillRectangle ((Display*) m_display, (Pixmap) m_pixmap, (GC) m_gc, 0, 0, w, h);
+    if( width ) *width = w;
+    if( height ) *height = h;
+}
 
-    if (m_window && m_window->GetBackingPixmap())
-        XFillRectangle ((Display*) m_display, (Pixmap) m_window->GetBackingPixmap(),(GC) m_gcBacking, 0, 0, w, h);
+void wxWindowDC::Clear()
+{
+    wxCHECK_RET( Ok(), "invalid dc" );
 
-    m_brush = saveBrush;
+    wxRect rect( GetSize() );
+    Clear( rect );
 }
 
 void wxWindowDC::Clear(const wxRect& rect)
@@ -1530,10 +1449,13 @@ void wxWindowDC::Clear(const wxRect& rect)
     wxBrush saveBrush = m_brush;
     SetBrush (m_backgroundBrush);
 
-    XFillRectangle ((Display*) m_display, (Pixmap) m_pixmap, (GC) m_gc, x, y, w, h);
+    XFillRectangle ((Display*) m_display, (Pixmap) m_pixmap, (GC) m_gc,
+                    x, y, w, h);
 
     if (m_window && m_window->GetBackingPixmap())
-        XFillRectangle ((Display*) m_display, (Pixmap) m_window->GetBackingPixmap(),(GC) m_gcBacking, x, y, w, h);
+        XFillRectangle ((Display*) m_display,
+                        (Pixmap) m_window->GetBackingPixmap(),(GC) m_gcBacking,
+                        x, y, w, h);
 
     m_brush = saveBrush;
 }
@@ -1589,7 +1511,7 @@ int wxWindowDC::CalculatePixel(wxColour& colour, wxColour& curCol,
                                bool roundToWhite) const
 {
     const unsigned char wp = (unsigned char)255;
-        
+
     int pixel = -1;
     if(!m_colour) // Mono display
     {
@@ -1873,7 +1795,7 @@ void wxWindowDC::SetPen( const wxPen &pen )
             pixel = m_backgroundPixel;
         else
         {
-            pixel = CalculatePixel(m_pen.GetColour(), m_currentColour, FALSE);
+            pixel = CalculatePixel(m_pen.GetColour(), m_currentColour, false);
         }
 
         // Finally, set the GC to the required colour
@@ -1937,7 +1859,7 @@ void wxWindowDC::SetBrush( const wxBrush &brush )
                 // determine whether fill style should be solid or
                 // transparent
                 int style = stippleDepth == 1 ?
-                    (m_backgroundMode == wxSOLID ? 
+                    (m_backgroundMode == wxSOLID ?
                      FillOpaqueStippled : FillStippled) :
                     FillTiled;
                 XSetFillStyle ((Display*) m_display, (GC) m_gc, style);
@@ -2035,8 +1957,8 @@ void wxWindowDC::SetBrush( const wxBrush &brush )
     // must test m_logicalFunction, because it involves background!
     if (!sameColour || !GetOptimization() || m_logicalFunction == wxXOR)
     {
-        int pixel = CalculatePixel(m_brush.GetColour(), m_currentColour, TRUE);
- 
+        int pixel = CalculatePixel(m_brush.GetColour(), m_currentColour, true);
+
         if (pixel > -1)
             SetForegroundPixelWithLogicalFunction(pixel);
     }
@@ -2055,14 +1977,6 @@ void wxWindowDC::SetBackground( const wxBrush &brush )
 
     m_backgroundPixel = m_backgroundBrush.GetColour().AllocColour(m_display);
 
-    // New behaviour, 10/2/99: setting the background brush of a DC
-    // doesn't affect the window background colour.
-/*
-    // XSetWindowBackground doesn't work for non-Window pixmaps
-    if (!this->IsKindOf(CLASSINFO(wxMemoryDC)))
-        XSetWindowBackground ((Display*) m_display, (Pixmap) m_pixmap, pixel);
-*/
-
     // Necessary for ::DrawIcon, which use fg/bg pixel or the GC.
     // And Blit,... (Any fct that use XCopyPlane, in fact.)
     XSetBackground ((Display*) m_display, (GC) m_gc, m_backgroundPixel);
@@ -2150,23 +2064,14 @@ void wxWindowDC::SetTextForeground( const wxColour &col )
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    if (m_textForegroundColour == col)
-        return;
-
     m_textForegroundColour = col;
-
 }
 
 void wxWindowDC::SetTextBackground( const wxColour &col )
 {
     wxCHECK_RET( Ok(), "invalid dc" );
 
-    if (m_textBackgroundColour == col)
-        return;
-
     m_textBackgroundColour = col;
-    if (!m_textBackgroundColour.Ok())
-        return;
 }
 
 void wxWindowDC::SetBackgroundMode( int mode )
@@ -2189,57 +2094,54 @@ void wxWindowDC::SetPalette( const wxPalette& palette )
     }
 }
 
-// Helper function
-void wxWindowDC::SetDCClipping()
+static void wxCopyRegion( WXRegion src, WXRegion& dst )
 {
-    // m_userRegion is the region set by calling SetClippingRegion
-
-    if (m_currentRegion)
-        XDestroyRegion ((Region) m_currentRegion);
-
-    // We need to take into account
-    // clipping imposed on a window by a repaint.
-    // We'll combine it with the user region. But for now,
-    // just use the currently-defined user clipping region.
-    if (m_userRegion || (m_window && m_window->GetUpdateRegion().Ok()) )
-        m_currentRegion = (WXRegion) XCreateRegion ();
-    else
-        m_currentRegion = (WXRegion) NULL;
-
-    if ((m_window && m_window->GetUpdateRegion().Ok()) && m_userRegion)
-        XIntersectRegion ((Region) m_window->GetUpdateRegion().GetXRegion(), (Region) m_userRegion, (Region) m_currentRegion);
-    else if (m_userRegion)
-        XIntersectRegion ((Region) m_userRegion, (Region) m_userRegion, (Region) m_currentRegion);
-    else if (m_window && m_window->GetUpdateRegion().Ok())
-        XIntersectRegion ((Region) m_window->GetUpdateRegion().GetXRegion(), (Region) m_window->GetUpdateRegion().GetXRegion(),
-        (Region) m_currentRegion);
+    if( !dst )
+        dst = XCreateRegion();
+    XUnionRegion( (Region)src, (Region)src, (Region)dst );
+}
 
-    if (m_currentRegion)
+// Helper function; userRegion is the region set by calling SetClippingRegion
+void wxWindowDC::SetDCClipping( WXRegion userRegion )
+{
+    bool hasUpdateRegion = m_window && m_window->GetUpdateRegion().Ok();
+    // this means that we should start the clip region from scratch,
+    // or from the update region, if any
+    if( !userRegion )
     {
-        XSetRegion ((Display*) m_display, (GC) m_gc, (Region) m_currentRegion);
+        if( m_clipRegion )
+            XDestroyRegion( (Region)m_clipRegion );
+        m_clipRegion = (WXRegion)NULL;
+
+        if( hasUpdateRegion )
+            wxCopyRegion( m_window->GetUpdateRegion().GetX11Region(),
+                          m_clipRegion );
     }
-    else
+    // intersect the user region, if any, with the
+    // exisiting clip region
+    else // if( userRegion )
     {
-        XSetClipMask ((Display*) m_display, (GC) m_gc, None);
+        if( !m_clipRegion )
+            wxCopyRegion( userRegion, m_clipRegion );
+        else
+            XIntersectRegion( (Region)m_clipRegion,
+                              (Region)userRegion, (Region)m_clipRegion );
     }
 
+    if( m_clipRegion )
+        XSetRegion( (Display*)m_display, (GC)m_gc, (Region)m_clipRegion );
+    else
+        XSetClipMask( (Display*)m_display, (GC)m_gc, None );
 }
 
-void wxWindowDC::DoSetClippingRegion( wxCoord x, wxCoord y, wxCoord width, wxCoord height )
+void wxWindowDC::DoSetClippingRegion( wxCoord x, wxCoord y,
+                                      wxCoord width, wxCoord height )
 {
     wxDC::DoSetClippingRegion( x, y, width, height );
 
-    if (m_userRegion)
-        XDestroyRegion ((Region) m_userRegion);
-    m_userRegion = (WXRegion) XCreateRegion ();
-    XRectangle r;
-    r.x = XLOG2DEV (x);
-    r.y = YLOG2DEV (y);
-    r.width = XLOG2DEVREL(width);
-    r.height = YLOG2DEVREL(height);
-    XUnionRectWithRegion (&r, (Region) m_userRegion, (Region) m_userRegion);
+    wxRegion temp(x, y, width, height);
 
-    SetDCClipping ();
+    SetDCClipping(temp.GetX11Region());
 
     // Needs to work differently for Pixmap: without this,
     // there's a nasty (Display*) m_display bug. 8/12/94
@@ -2250,7 +2152,8 @@ void wxWindowDC::DoSetClippingRegion( wxCoord x, wxCoord y, wxCoord width, wxCoo
         rects[0].y = YLOG2DEV_2(y);
         rects[0].width = XLOG2DEVREL(width);
         rects[0].height = YLOG2DEVREL(height);
-        XSetClipRectangles((Display*) m_display, (GC) m_gcBacking, 0, 0, rects, 1, Unsorted);
+        XSetClipRectangles((Display*) m_display, (GC) m_gcBacking,
+                           0, 0, rects, 1, Unsorted);
     }
 }
 
@@ -2260,13 +2163,7 @@ void wxWindowDC::DoSetClippingRegionAsRegion( const wxRegion& region )
 
     wxDC::DoSetClippingRegion( box.x, box.y, box.width, box.height );
 
-    if (m_userRegion)
-        XDestroyRegion ((Region) m_userRegion);
-    m_userRegion = (WXRegion) XCreateRegion ();
-
-    XUnionRegion((Region) m_userRegion, (Region) region.GetXRegion(), (Region) m_userRegion);
-
-    SetDCClipping ();
+    SetDCClipping(region.GetX11Region());
 
     // Needs to work differently for Pixmap: without this,
     // there's a nasty (Display*) m_display bug. 8/12/94
@@ -2277,7 +2174,8 @@ void wxWindowDC::DoSetClippingRegionAsRegion( const wxRegion& region )
         rects[0].y = YLOG2DEV_2(box.y);
         rects[0].width = XLOG2DEVREL(box.width);
         rects[0].height = YLOG2DEVREL(box.height);
-        XSetClipRectangles((Display*) m_display, (GC) m_gcBacking, 0, 0, rects, 1, Unsorted);
+        XSetClipRectangles((Display*) m_display, (GC) m_gcBacking,
+                           0, 0, rects, 1, Unsorted);
     }
 }
 
@@ -2286,21 +2184,16 @@ void wxWindowDC::DestroyClippingRegion()
 {
     wxDC::DestroyClippingRegion();
 
-    if (m_userRegion)
-        XDestroyRegion ((Region) m_userRegion);
-    m_userRegion = NULL;
-
-    SetDCClipping ();
+    SetDCClipping(NULL);
 
-    XGCValues gc_val;
-    gc_val.clip_mask = None;
     if (m_window && m_window->GetBackingPixmap())
-        XChangeGC((Display*) m_display, (GC) m_gcBacking, GCClipMask, &gc_val);
+        XSetClipMask ((Display*) m_display, (GC) m_gcBacking, None);
 }
 
 // Resolution in pixels per logical inch
 wxSize wxWindowDC::GetPPI() const
 {
+    // TODO
     return wxSize(100, 100);
 }
 
@@ -2319,51 +2212,15 @@ int wxWindowDC::GetDepth() const
 
 wxPaintDC::wxPaintDC(wxWindow* win) : wxWindowDC(win)
 {
-    wxRegion* region = NULL;
-
-    // Combine all the update rects into a region
-    const wxRectList& updateRects(win->GetUpdateRects());
-    if ( updateRects.GetCount() != 0 )
-    {
-        for ( wxRectList::Node *node = updateRects.GetFirst();
-              node;
-              node = node->GetNext() )
-        {
-            wxRect* rect = node->GetData();
-
-            if (!region)
-                region = new wxRegion(*rect);
-            else
-                // TODO: is this correct? In SetDCClipping above,
-                // XIntersectRegion is used to combine paint and user
-                // regions. XIntersectRegion appears to work in that case...
-                region->Union(*rect);
-        }
-    }
-    else
-    {
-        int cw, ch;
-        win->GetClientSize(&cw, &ch);
-        region = new wxRegion(wxRect(0, 0, cw, ch));
-    }
-
-    win->SetUpdateRegion(*region);
-
-    wxRegion& theRegion(win->GetUpdateRegion());
-    theRegion.SetRects(updateRects); // We also store in terms of rects, for iteration to work.
-
-    // Set the clipping region. Any user-defined region will be combined with this
-    // one in SetDCClipping.
-    XSetRegion ((Display*) m_display, (GC) m_gc, (Region) region->GetXRegion());
-
-    delete region;
+    // Set the clipping region.to the update region
+    SetDCClipping((WXRegion)NULL);
 }
 
 wxPaintDC::~wxPaintDC()
 {
-    XSetClipMask ((Display*) m_display, (GC) m_gc, None);
     if (m_window)
         m_window->ClearUpdateRegion();
+    SetDCClipping((WXRegion)NULL);
 }
 
 // ----------------------------------------------------------------------------