From 74ab0bfbb7a0713ed0c6830cc3b27bc6a9128194 Mon Sep 17 00:00:00 2001
From: Robert Roebling <robert@roebling.de>
Date: Fri, 24 Feb 2006 09:36:35 +0000
Subject: [PATCH]   New implementation for printing circles and epllipses.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@37698 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 include/wx/gtk/gnome/gprint.h |  2 +
 src/gtk/gnome/gprint.cpp      | 84 ++++++++++++++++++++---------------
 2 files changed, 50 insertions(+), 36 deletions(-)

diff --git a/include/wx/gtk/gnome/gprint.h b/include/wx/gtk/gnome/gprint.h
index 9397e2f3af..eb5764a170 100644
--- a/include/wx/gtk/gnome/gprint.h
+++ b/include/wx/gtk/gnome/gprint.h
@@ -285,6 +285,8 @@ private:
     wxGnomePrinter         *m_printer;
     GnomePrintContext      *m_gpc;
 
+    void makeEllipticalPath(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
+    
 private:
     wxCoord XDEV2LOG(wxCoord x) const
     {
diff --git a/src/gtk/gnome/gprint.cpp b/src/gtk/gnome/gprint.cpp
index c9c378e560..ab2d2db204 100644
--- a/src/gtk/gnome/gprint.cpp
+++ b/src/gtk/gnome/gprint.cpp
@@ -1155,30 +1155,59 @@ void wxGnomePrintDC::DoDrawRoundedRectangle(wxCoord x, wxCoord y, wxCoord width,
     }
 }
 
+void wxGnomePrintDC::makeEllipticalPath(wxCoord x, wxCoord y, 
+                                        wxCoord width, wxCoord height)
+{
+    double r = 4 * (sqrt (2) - 1) / 3;
+    double  halfW = 0.5 * width,
+            halfH = 0.5 * height,
+            halfWR = r * halfW,
+            halfHR = r * halfH;
+    wxCoord halfWI = (wxCoord) halfW,
+            halfHI = (wxCoord) halfH;
+            
+    gs_lgp->gnome_print_newpath( m_gpc );
+    
+    // Approximate an ellipse using four cubic splines, clockwise from 0 deg */
+    gs_lgp->gnome_print_moveto( m_gpc,
+                XLOG2DEV(x + width), 
+                YLOG2DEV(y + halfHI) );
+    gs_lgp->gnome_print_curveto( m_gpc,
+                XLOG2DEV(x + width),
+                YLOG2DEV(y + (wxCoord) rint (halfH + halfHR)),
+                XLOG2DEV(x + (wxCoord) rint(halfW + halfWR)), 
+                YLOG2DEV(y + height),
+                XLOG2DEV(x + halfWI), 
+                YLOG2DEV(y + height) );
+    gs_lgp->gnome_print_curveto( m_gpc,
+                XLOG2DEV(x + (wxCoord) rint(halfW - halfWR)), 
+                YLOG2DEV(y + height),
+                XLOG2DEV(x),
+                YLOG2DEV(y + (wxCoord) rint (halfH + halfHR)),
+                XLOG2DEV(x), YLOG2DEV(y+halfHI) );
+    gs_lgp->gnome_print_curveto( m_gpc,
+                XLOG2DEV(x),
+                YLOG2DEV(y + (wxCoord) rint (halfH - halfHR)),
+                XLOG2DEV(x + (wxCoord) rint (halfW - halfWR)),
+                YLOG2DEV(y),
+                XLOG2DEV(x+halfWI), YLOG2DEV(y) );
+    gs_lgp->gnome_print_curveto( m_gpc,
+                XLOG2DEV(x + (wxCoord) rint(halfW + halfWR)),
+                YLOG2DEV(y),
+                XLOG2DEV(x + width),
+                YLOG2DEV(y + (wxCoord) rint(halfH - halfHR)),
+                XLOG2DEV(x + width), YLOG2DEV(y + halfHI) );
+                
+    gs_lgp->gnome_print_closepath(m_gpc);
+}
+
 void wxGnomePrintDC::DoDrawEllipse(wxCoord x, wxCoord y, wxCoord width, wxCoord height)
 {
     if (m_brush.GetStyle () != wxTRANSPARENT)
     {
         SetBrush( m_brush );
-
-        gs_lgp->gnome_print_newpath( m_gpc );
-        gs_lgp->gnome_print_moveto( m_gpc,
-                            XLOG2DEV(x), YLOG2DEV(y+height/2) );
-
-        // start with top half
-        gs_lgp->gnome_print_curveto( m_gpc,
-                            XLOG2DEV(x), YLOG2DEV(y),
-                            XLOG2DEV(x+width), YLOG2DEV(y),
-                            XLOG2DEV(x+width), YLOG2DEV(y+height/2) );
-        // lower half
-        gs_lgp->gnome_print_curveto( m_gpc,
-                            XLOG2DEV(x+width), YLOG2DEV(y+height),
-                            XLOG2DEV(x), YLOG2DEV(y+height),
-                            XLOG2DEV(x), YLOG2DEV(y+height/2) );
-
-        gs_lgp->gnome_print_closepath( m_gpc );
+        makeEllipticalPath( x, y, width, height );
         gs_lgp->gnome_print_fill( m_gpc );
-
         CalcBoundingBox( x, y );
         CalcBoundingBox( x + width, y + height );
     }
@@ -1186,25 +1215,8 @@ void wxGnomePrintDC::DoDrawEllipse(wxCoord x, wxCoord y, wxCoord width, wxCoord
     if (m_pen.GetStyle () != wxTRANSPARENT)
     {
         SetPen (m_pen);
-
-        gs_lgp->gnome_print_newpath( m_gpc );
-        gs_lgp->gnome_print_moveto( m_gpc,
-                            XLOG2DEV(x), YLOG2DEV(y+height/2) );
-
-        // start with top half
-        gs_lgp->gnome_print_curveto( m_gpc,
-                            XLOG2DEV(x), YLOG2DEV(y),
-                            XLOG2DEV(x+width), YLOG2DEV(y),
-                            XLOG2DEV(x+width), YLOG2DEV(y+height/2) );
-        // lower half
-        gs_lgp->gnome_print_curveto( m_gpc,
-                            XLOG2DEV(x+width), YLOG2DEV(y+height),
-                            XLOG2DEV(x), YLOG2DEV(y+height),
-                            XLOG2DEV(x), YLOG2DEV(y+height/2) );
-
-        gs_lgp->gnome_print_closepath( m_gpc );
+        makeEllipticalPath( x, y, width, height );
         gs_lgp->gnome_print_stroke( m_gpc );
-
         CalcBoundingBox( x, y );
         CalcBoundingBox( x + width, y + height );
     }
-- 
2.45.2