+ wxPoint *point1 = new wxPoint;
+ point1->x = x1; point1->y = y1;
+ point_list.Append( point1 );
+
+ wxPoint *point2 = new wxPoint;
+ point2->x = x2; point2->y = y2;
+ point_list.Append( point2 );
+
+ wxPoint *point3 = new wxPoint;
+ point3->x = x3; point3->y = y3;
+ point_list.Append( point3 );
+
+ DoDrawSpline(&point_list);
+
+ for( wxPointList::compatibility_iterator node = point_list.GetFirst(); node; node = node->GetNext() )
+ {
+ wxPoint *p = node->GetData();
+ delete p;
+ }
+}
+
+void wxDCImpl::DoDrawSpline(int n, wxPoint points[])
+{
+ wxPointList list;
+ for (int i =0; i < n; i++)
+ list.Append( &points[i] );
+
+ DoDrawSpline(&list);
+}
+
+// ----------------------------------- spline code ----------------------------------------
+
+void wx_quadratic_spline(double a1, double b1, double a2, double b2,
+ double a3, double b3, double a4, double b4);
+void wx_clear_stack();
+int wx_spline_pop(double *x1, double *y1, double *x2, double *y2, double *x3,
+ double *y3, double *x4, double *y4);
+void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3,
+ double x4, double y4);
+static bool wx_spline_add_point(double x, double y);
+static void wx_spline_draw_point_array(wxDC *dc);
+
+wxPointList wx_spline_point_list;
+
+#define half(z1, z2) ((z1+z2)/2.0)
+#define THRESHOLD 5
+
+/* iterative version */
+
+void wx_quadratic_spline(double a1, double b1, double a2, double b2, double a3, double b3, double a4,
+ double b4)
+{
+ register double xmid, ymid;
+ double x1, y1, x2, y2, x3, y3, x4, y4;
+
+ wx_clear_stack();
+ wx_spline_push(a1, b1, a2, b2, a3, b3, a4, b4);
+
+ while (wx_spline_pop(&x1, &y1, &x2, &y2, &x3, &y3, &x4, &y4)) {
+ xmid = (double)half(x2, x3);
+ ymid = (double)half(y2, y3);
+ if (fabs(x1 - xmid) < THRESHOLD && fabs(y1 - ymid) < THRESHOLD &&
+ fabs(xmid - x4) < THRESHOLD && fabs(ymid - y4) < THRESHOLD) {
+ wx_spline_add_point( x1, y1 );
+ wx_spline_add_point( xmid, ymid );
+ } else {
+ wx_spline_push(xmid, ymid, (double)half(xmid, x3), (double)half(ymid, y3),
+ (double)half(x3, x4), (double)half(y3, y4), x4, y4);
+ wx_spline_push(x1, y1, (double)half(x1, x2), (double)half(y1, y2),
+ (double)half(x2, xmid), (double)half(y2, ymid), xmid, ymid);
+ }
+ }
+}
+
+/* utilities used by spline drawing routines */
+
+typedef struct wx_spline_stack_struct {
+ double x1, y1, x2, y2, x3, y3, x4, y4;
+} Stack;
+
+#define SPLINE_STACK_DEPTH 20
+static Stack wx_spline_stack[SPLINE_STACK_DEPTH];
+static Stack *wx_stack_top;
+static int wx_stack_count;
+
+void wx_clear_stack()
+{
+ wx_stack_top = wx_spline_stack;
+ wx_stack_count = 0;
+}
+
+void wx_spline_push(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4)
+{
+ wx_stack_top->x1 = x1;
+ wx_stack_top->y1 = y1;
+ wx_stack_top->x2 = x2;
+ wx_stack_top->y2 = y2;
+ wx_stack_top->x3 = x3;
+ wx_stack_top->y3 = y3;
+ wx_stack_top->x4 = x4;
+ wx_stack_top->y4 = y4;
+ wx_stack_top++;
+ wx_stack_count++;
+}
+
+int wx_spline_pop(double *x1, double *y1, double *x2, double *y2,
+ double *x3, double *y3, double *x4, double *y4)
+{
+ if (wx_stack_count == 0)
+ return (0);
+ wx_stack_top--;
+ wx_stack_count--;
+ *x1 = wx_stack_top->x1;
+ *y1 = wx_stack_top->y1;
+ *x2 = wx_stack_top->x2;
+ *y2 = wx_stack_top->y2;
+ *x3 = wx_stack_top->x3;
+ *y3 = wx_stack_top->y3;
+ *x4 = wx_stack_top->x4;
+ *y4 = wx_stack_top->y4;
+ return (1);
+}
+
+static bool wx_spline_add_point(double x, double y)
+{
+ wxPoint *point = new wxPoint( wxRound(x), wxRound(y) );
+ wx_spline_point_list.Append(point );
+ return true;
+}
+
+static void wx_spline_draw_point_array(wxDC *dc)
+{
+ dc->DrawLines(&wx_spline_point_list, 0, 0 );
+ wxPointList::compatibility_iterator node = wx_spline_point_list.GetFirst();
+ while (node)
+ {
+ wxPoint *point = node->GetData();
+ delete point;
+ wx_spline_point_list.Erase(node);
+ node = wx_spline_point_list.GetFirst();
+ }
+}
+
+void wxDCImpl::DoDrawSpline( const wxPointList *points )
+{
+ wxCHECK_RET( IsOk(), wxT("invalid window dc") );
+
+ wxPoint *p;
+ double cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4;
+ double x1, y1, x2, y2;
+
+ wxPointList::compatibility_iterator node = points->GetFirst();
+ if (!node)
+ // empty list
+ return;
+
+ p = (wxPoint *)node->GetData();
+
+ x1 = p->x;
+ y1 = p->y;
+
+ node = node->GetNext();
+ p = node->GetData();
+
+ x2 = p->x;
+ y2 = p->y;
+ cx1 = (double)((x1 + x2) / 2);
+ cy1 = (double)((y1 + y2) / 2);
+ cx2 = (double)((cx1 + x2) / 2);
+ cy2 = (double)((cy1 + y2) / 2);
+
+ wx_spline_add_point(x1, y1);
+
+ while ((node = node->GetNext())
+#if !wxUSE_STL
+ != NULL
+#endif // !wxUSE_STL
+ )
+ {
+ p = node->GetData();
+ x1 = x2;
+ y1 = y2;
+ x2 = p->x;
+ y2 = p->y;
+ cx4 = (double)(x1 + x2) / 2;
+ cy4 = (double)(y1 + y2) / 2;
+ cx3 = (double)(x1 + cx4) / 2;
+ cy3 = (double)(y1 + cy4) / 2;
+
+ wx_quadratic_spline(cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4);
+
+ cx1 = cx4;
+ cy1 = cy4;
+ cx2 = (double)(cx1 + x2) / 2;
+ cy2 = (double)(cy1 + y2) / 2;
+ }
+
+ wx_spline_add_point( cx1, cy1 );
+ wx_spline_add_point( x2, y2 );
+
+ wx_spline_draw_point_array( m_owner );
+}
+
+#endif // wxUSE_SPLINES
+
+
+
+void wxDCImpl::DoGradientFillLinear(const wxRect& rect,
+ const wxColour& initialColour,
+ const wxColour& destColour,
+ wxDirection nDirection)
+{
+ // save old pen
+ wxPen oldPen = m_pen;
+ wxBrush oldBrush = m_brush;
+
+ wxUint8 nR1 = initialColour.Red();
+ wxUint8 nG1 = initialColour.Green();
+ wxUint8 nB1 = initialColour.Blue();
+ wxUint8 nR2 = destColour.Red();
+ wxUint8 nG2 = destColour.Green();
+ wxUint8 nB2 = destColour.Blue();