/////////////////////////////////////////////////////////////////////////////
-// Name: dc.cpp
-// Purpose: wxDC Class
-// Author: Brian Macy
+// Name: common/dcbase.cpp
+// Purpose: generic methods of the wxDC Class
+// Author: Vadim Zeitlin
// Modified by:
// Created: 05/25/99
// RCS-ID: $Id$
-// Copyright: (c) wxWindows team
-// Licence: wxWindows license
+// Copyright: (c) wxWidgets team
+// Licence: wxWidgets licence
/////////////////////////////////////////////////////////////////////////////
-#ifdef __GNUG__
-#pragma implementation "dcbase.h"
+// ============================================================================
+// declarations
+// ============================================================================
+
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
+ #pragma implementation "dcbase.h"
#endif
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"
#pragma hdrstop
#endif
-#ifndef WX_PRECOMP
- #include "wx/window.h"
-#endif
+#include "wx/dc.h"
-#ifdef __WXMSW__
- #include "wx/msw/private.h"
-#endif
+#include <math.h>
-#include "wx/dc.h"
+// bool wxDCBase::sm_cacheing = FALSE;
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// special symbols
+// ----------------------------------------------------------------------------
+
+void wxDCBase::DoDrawCheckMark(wxCoord x1, wxCoord y1,
+ wxCoord width, wxCoord height)
+{
+ wxCHECK_RET( Ok(), wxT("invalid window dc") );
+
+ wxCoord x2 = x1 + width,
+ y2 = y1 + height;
+
+ // this is to yield width of 3 for width == height == 10
+ SetPen(wxPen(GetTextForeground(), (width + height + 1) / 7, wxSOLID));
+
+ // we're drawing a scaled version of wx/generic/tick.xpm here
+ wxCoord x3 = x1 + (4*width) / 10, // x of the tick bottom
+ y3 = y1 + height / 2; // y of the left tick branch
+ DoDrawLine(x1, y3, x3, y2);
+ DoDrawLine(x3, y2, x2, y1);
+
+ CalcBoundingBox(x1, y1);
+ CalcBoundingBox(x2, y2);
+}
+
+// ----------------------------------------------------------------------------
+// line/polygons
+// ----------------------------------------------------------------------------
void wxDCBase::DrawLines(const wxList *list, wxCoord xoffset, wxCoord yoffset)
{
- int n = list->Number();
+ int n = list->GetCount();
wxPoint *points = new wxPoint[n];
int i = 0;
- for ( wxNode *node = list->First(); node; node = node->Next(), i++ )
+ for ( wxList::compatibility_iterator node = list->GetFirst(); node; node = node->GetNext(), i++ )
{
- wxPoint *point = (wxPoint *)node->Data();
+ wxPoint *point = (wxPoint *)node->GetData();
points[i].x = point->x;
points[i].y = point->y;
}
wxCoord xoffset, wxCoord yoffset,
int fillStyle)
{
- int n = list->Number();
+ int n = list->GetCount();
wxPoint *points = new wxPoint[n];
int i = 0;
- for ( wxNode *node = list->First(); node; node = node->Next(), i++ )
+ for ( wxList::compatibility_iterator node = list->GetFirst(); node; node = node->GetNext(), i++ )
{
- wxPoint *point = (wxPoint *)node->Data();
+ wxPoint *point = (wxPoint *)node->GetData();
points[i].x = point->x;
points[i].y = point->y;
}
delete [] points;
}
+void
+wxDCBase::DoDrawPolyPolygon(int n,
+ int count[],
+ wxPoint points[],
+ wxCoord xoffset, wxCoord yoffset,
+ int fillStyle)
+{
+ if ( n == 1 )
+ {
+ DoDrawPolygon(count[0], points, xoffset, yoffset, fillStyle);
+ return;
+ }
+
+ int i, j, lastOfs;
+ wxPoint* pts;
+ wxPen pen;
+
+ for (i = j = lastOfs = 0; i < n; i++)
+ {
+ lastOfs = j;
+ j += count[i];
+ }
+ pts = new wxPoint[j+n-1];
+ for (i = 0; i < j; i++)
+ pts[i] = points[i];
+ for (i = 2; i <= n; i++)
+ {
+ lastOfs -= count[n-i];
+ pts[j++] = pts[lastOfs];
+ }
+
+ pen = GetPen();
+ SetPen(wxPen(*wxBLACK, 0, wxTRANSPARENT));
+ DoDrawPolygon(j, pts, xoffset, yoffset, fillStyle);
+ SetPen(pen);
+ for (i = j = 0; i < n; i++)
+ {
+ DoDrawLines(count[i], pts+j, xoffset, yoffset);
+ j += count[i];
+ }
+ delete[] pts;
+}
+
+// ----------------------------------------------------------------------------
+// splines
+// ----------------------------------------------------------------------------
#if wxUSE_SPLINES
DrawSpline(&point_list);
- for( wxNode *node = point_list.First(); node; node = node->Next() )
+ for( wxList::compatibility_iterator node = point_list.GetFirst(); node; node = node->GetNext() )
{
- wxPoint *p = (wxPoint *)node->Data();
+ wxPoint *p = (wxPoint *)node->GetData();
delete p;
}
}
DrawSpline(&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(wxDCBase *dc);
+
+wxList 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 ;
+ point->x = (int) x;
+ point->y = (int) y;
+ wx_spline_point_list.Append((wxObject*)point);
+ return TRUE;
+}
+
+static void wx_spline_draw_point_array(wxDCBase *dc)
+{
+ dc->DrawLines(&wx_spline_point_list, 0, 0 );
+ wxList::compatibility_iterator node = wx_spline_point_list.GetFirst();
+ while (node)
+ {
+ wxPoint *point = (wxPoint *)node->GetData();
+ delete point;
+ wx_spline_point_list.Erase(node);
+ node = wx_spline_point_list.GetFirst();
+ }
+}
+
+void wxDCBase::DoDrawSpline( wxList *points )
+{
+ wxCHECK_RET( Ok(), wxT("invalid window dc") );
+
+ wxPoint *p;
+ double cx1, cy1, cx2, cy2, cx3, cy3, cx4, cy4;
+ double x1, y1, x2, y2;
+
+ wxList::compatibility_iterator node = points->GetFirst();
+ p = (wxPoint *)node->GetData();
+
+ x1 = p->x;
+ y1 = p->y;
+
+ node = node->GetNext();
+ p = (wxPoint *)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 = (wxPoint *)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( this );
+}
+
#endif // wxUSE_SPLINES
+
+// ----------------------------------------------------------------------------
+// Partial Text Extents
+// ----------------------------------------------------------------------------
+
+
+// Each element of the widths array will be the width of the string up to and
+// including the coresoponding character in text. This is the generic
+// implementation, the port-specific classes should do this with native APIs
+// if available and if faster. Note: pango_layout_index_to_pos is much slower
+// than calling GetTextExtent!!
+
+#define FWC_SIZE 128
+
+class FontWidthCache
+{
+public:
+ FontWidthCache() : m_scaleX(1), m_widths(NULL) { }
+ ~FontWidthCache() { delete []m_widths; }
+
+ void Reset()
+ {
+ if (!m_widths)
+ m_widths = new int[FWC_SIZE];
+
+ memset(m_widths, 0, sizeof(int)*FWC_SIZE);
+ }
+
+ wxFont m_font;
+ double m_scaleX;
+ int *m_widths;
+};
+
+static FontWidthCache s_fontWidthCache;
+
+bool wxDCBase::DoGetPartialTextExtents(const wxString& text, wxArrayInt& widths) const
+{
+ int totalWidth = 0;
+
+ size_t i, len = text.Length();
+ widths.Empty();
+ widths.Add(0, len);
+ int w, h;
+
+ // reset the cache if font or horizontal scale have changed
+ if (!s_fontWidthCache.m_widths ||
+ (s_fontWidthCache.m_scaleX != m_scaleX) ||
+ (s_fontWidthCache.m_font != GetFont()))
+ {
+ s_fontWidthCache.Reset();
+ s_fontWidthCache.m_font = GetFont();
+ s_fontWidthCache.m_scaleX = m_scaleX;
+ }
+
+ // Calculate the position of each character based on the widths of
+ // the previous characters
+ for (i=0; i<len; i++)
+ {
+ const wxChar c = text[i];
+ unsigned int c_int = (unsigned int)c;
+
+ if ((c_int < FWC_SIZE) && (s_fontWidthCache.m_widths[c_int] != 0))
+ {
+ w = s_fontWidthCache.m_widths[c_int];
+ }
+ else
+ {
+ GetTextExtent(c, &w, &h);
+ if (c_int < FWC_SIZE)
+ s_fontWidthCache.m_widths[c_int] = w;
+ }
+
+ totalWidth += w;
+ widths[i] = totalWidth;
+ }
+
+ return true;
+}
+
+
+// ----------------------------------------------------------------------------
+// enhanced text drawing
+// ----------------------------------------------------------------------------
+
+void wxDCBase::GetMultiLineTextExtent(const wxString& text,
+ wxCoord *x,
+ wxCoord *y,
+ wxCoord *h,
+ wxFont *font)
+{
+ wxCoord widthTextMax = 0, widthLine,
+ heightTextTotal = 0, heightLineDefault = 0, heightLine = 0;
+
+ wxString curLine;
+ for ( const wxChar *pc = text; ; pc++ )
+ {
+ if ( *pc == _T('\n') || *pc == _T('\0') )
+ {
+ if ( curLine.empty() )
+ {
+ // we can't use GetTextExtent - it will return 0 for both width
+ // and height and an empty line should count in height
+ // calculation
+
+ // assume that this line has the same height as the previous
+ // one
+ if ( !heightLineDefault )
+ heightLineDefault = heightLine;
+
+ if ( !heightLineDefault )
+ {
+ // but we don't know it yet - choose something reasonable
+ GetTextExtent(_T("W"), NULL, &heightLineDefault,
+ NULL, NULL, font);
+ }
+
+ heightTextTotal += heightLineDefault;
+ }
+ else
+ {
+ GetTextExtent(curLine, &widthLine, &heightLine,
+ NULL, NULL, font);
+ if ( widthLine > widthTextMax )
+ widthTextMax = widthLine;
+ heightTextTotal += heightLine;
+ }
+
+ if ( *pc == _T('\n') )
+ {
+ curLine.clear();
+ }
+ else
+ {
+ // the end of string
+ break;
+ }
+ }
+ else
+ {
+ curLine += *pc;
+ }
+ }
+
+ if ( x )
+ *x = widthTextMax;
+ if ( y )
+ *y = heightTextTotal;
+ if ( h )
+ *h = heightLine;
+}
+
+void wxDCBase::DrawLabel(const wxString& text,
+ const wxBitmap& bitmap,
+ const wxRect& rect,
+ int alignment,
+ int indexAccel,
+ wxRect *rectBounding)
+{
+ // find the text position
+ wxCoord widthText, heightText, heightLine;
+ GetMultiLineTextExtent(text, &widthText, &heightText, &heightLine);
+
+ wxCoord width, height;
+ if ( bitmap.Ok() )
+ {
+ width = widthText + bitmap.GetWidth();
+ height = bitmap.GetHeight();
+ }
+ else // no bitmap
+ {
+ width = widthText;
+ height = heightText;
+ }
+
+ wxCoord x, y;
+ if ( alignment & wxALIGN_RIGHT )
+ {
+ x = rect.GetRight() - width;
+ }
+ else if ( alignment & wxALIGN_CENTRE_HORIZONTAL )
+ {
+ x = (rect.GetLeft() + rect.GetRight() + 1 - width) / 2;
+ }
+ else // alignment & wxALIGN_LEFT
+ {
+ x = rect.GetLeft();
+ }
+
+ if ( alignment & wxALIGN_BOTTOM )
+ {
+ y = rect.GetBottom() - height;
+ }
+ else if ( alignment & wxALIGN_CENTRE_VERTICAL )
+ {
+ y = (rect.GetTop() + rect.GetBottom() + 1 - height) / 2;
+ }
+ else // alignment & wxALIGN_TOP
+ {
+ y = rect.GetTop();
+ }
+
+ // draw the bitmap first
+ wxCoord x0 = x,
+ y0 = y,
+ width0 = width;
+ if ( bitmap.Ok() )
+ {
+ DrawBitmap(bitmap, x, y, TRUE /* use mask */);
+
+ wxCoord offset = bitmap.GetWidth() + 4;
+ x += offset;
+ width -= offset;
+
+ y += (height - heightText) / 2;
+ }
+
+ // we will draw the underscore under the accel char later
+ wxCoord startUnderscore = 0,
+ endUnderscore = 0,
+ yUnderscore = 0;
+
+ // split the string into lines and draw each of them separately
+ wxString curLine;
+ for ( const wxChar *pc = text; ; pc++ )
+ {
+ if ( *pc == _T('\n') || *pc == _T('\0') )
+ {
+ int xRealStart = x; // init it here to avoid compielr warnings
+
+ if ( !curLine.empty() )
+ {
+ // NB: can't test for !(alignment & wxALIGN_LEFT) because
+ // wxALIGN_LEFT is 0
+ if ( alignment & (wxALIGN_RIGHT | wxALIGN_CENTRE_HORIZONTAL) )
+ {
+ wxCoord widthLine;
+ GetTextExtent(curLine, &widthLine, NULL);
+
+ if ( alignment & wxALIGN_RIGHT )
+ {
+ xRealStart += width - widthLine;
+ }
+ else // if ( alignment & wxALIGN_CENTRE_HORIZONTAL )
+ {
+ xRealStart += (width - widthLine) / 2;
+ }
+ }
+ //else: left aligned, nothing to do
+
+ DrawText(curLine, xRealStart, y);
+ }
+
+ y += heightLine;
+
+ // do we have underscore in this line? we can check yUnderscore
+ // because it is set below to just y + heightLine if we do
+ if ( y == yUnderscore )
+ {
+ // adjust the horz positions to account for the shift
+ startUnderscore += xRealStart;
+ endUnderscore += xRealStart;
+ }
+
+ if ( *pc == _T('\0') )
+ break;
+
+ curLine.clear();
+ }
+ else // not end of line
+ {
+ if ( pc - text.c_str() == indexAccel )
+ {
+ // remeber to draw underscore here
+ GetTextExtent(curLine, &startUnderscore, NULL);
+ curLine += *pc;
+ GetTextExtent(curLine, &endUnderscore, NULL);
+
+ yUnderscore = y + heightLine;
+ }
+ else
+ {
+ curLine += *pc;
+ }
+ }
+ }
+
+ // draw the underscore if found
+ if ( startUnderscore != endUnderscore )
+ {
+ // it should be of the same colour as text
+ SetPen(wxPen(GetTextForeground(), 0, wxSOLID));
+
+ yUnderscore--;
+
+ DrawLine(startUnderscore, yUnderscore, endUnderscore, yUnderscore);
+ }
+
+ // return bounding rect if requested
+ if ( rectBounding )
+ {
+ *rectBounding = wxRect(x, y - heightText, widthText, heightText);
+ }
+
+ CalcBoundingBox(x0, y0);
+ CalcBoundingBox(x0 + width0, y0 + height);
+}
+
+/*
+Notes for wxWidgets DrawEllipticArcRot(...)
+
+wxDCBase::DrawEllipticArcRot(...) draws a rotated elliptic arc or an ellipse.
+It uses wxDCBase::CalculateEllipticPoints(...) and wxDCBase::Rotate(...),
+which are also new.
+
+All methods are generic, so they can be implemented in wxDCBase.
+DoDrawEllipticArcRot(...) is virtual, so it can be called from deeper
+methods like (WinCE) wxDC::DoDrawArc(...).
+
+CalculateEllipticPoints(...) fills a given list of wxPoints with some points
+of an elliptic arc. The algorithm is pixel-based: In every row (in flat
+parts) or every column (in steep parts) only one pixel is calculated.
+Trigonometric calculation (sin, cos, tan, atan) is only done if the
+starting angle is not equal to the ending angle. The calculation of the
+pixels is done using simple arithmetic only and should perform not too
+bad even on devices without floating point processor. I didn't test this yet.
+
+Rotate(...) rotates a list of point pixel-based, you will see rounding errors.
+For instance: an ellipse rotated 180 degrees is drawn
+slightly different from the original.
+
+The points are then moved to an array and used to draw a polyline and/or polygon
+(with center added, the pie).
+The result looks quite similar to the native ellipse, only e few pixels differ.
+
+The performance on a desktop system (Athlon 1800, WinXP) is about 7 times
+slower as DrawEllipse(...), which calls the native API.
+An rotated ellipse outside the clipping region takes nearly the same time,
+while an native ellipse outside takes nearly no time to draw.
+
+If you draw an arc with this new method, you will see the starting and ending angles
+are calculated properly.
+If you use DrawEllipticArc(...), you will see they are only correct for circles
+and not properly calculated for ellipses.
+
+Peter Lenhard
+p.lenhard@t-online.de
+*/
+
+#ifdef __WXWINCE__
+void wxDCBase::DoDrawEllipticArcRot( wxCoord x, wxCoord y,
+ wxCoord w, wxCoord h,
+ double sa, double ea, double angle )
+{
+ wxList list;
+
+ CalculateEllipticPoints( &list, x, y, w, h, sa, ea );
+ Rotate( &list, angle, wxPoint( x+w/2, y+h/2 ) );
+
+ // Add center (for polygon/pie)
+ list.Append( (wxObject*) new wxPoint( x+w/2, y+h/2 ) );
+
+ // copy list into array and delete list elements
+ int n = list.Number();
+ wxPoint *points = new wxPoint[n];
+ int i = 0;
+ wxNode* node = 0;
+ for ( node = list.First(); node; node = node->Next(), i++ )
+ {
+ wxPoint *point = (wxPoint *)node->Data();
+ points[i].x = point->x;
+ points[i].y = point->y;
+ delete point;
+ }
+
+ // first draw the pie without pen, if necessary
+ if( GetBrush() != *wxTRANSPARENT_BRUSH )
+ {
+ wxPen tempPen( GetPen() );
+ SetPen( *wxTRANSPARENT_PEN );
+ DoDrawPolygon( n, points, 0, 0 );
+ SetPen( tempPen );
+ }
+
+ // then draw the arc without brush, if necessary
+ if( GetPen() != *wxTRANSPARENT_PEN )
+ {
+ // without center
+ DoDrawLines( n-1, points, 0, 0 );
+ }
+
+ delete [] points;
+
+} // DrawEllipticArcRot
+
+void wxDCBase::Rotate( wxList* points, double angle, wxPoint center )
+{
+ if( angle != 0.0 )
+ {
+ double pi(3.1415926536);
+ double dSinA = -sin(angle*2.0*pi/360.0);
+ double dCosA = cos(angle*2.0*pi/360.0);
+ for ( wxNode* node = points->First(); node; node = node->Next() )
+ {
+ wxPoint* point = (wxPoint*)node->Data();
+
+ // transform coordinates, if necessary
+ if( center.x ) point->x -= center.x;
+ if( center.y ) point->y -= center.y;
+
+ // calculate rotation, rounding simply by implicit cast to integer
+ int xTemp = point->x * dCosA - point->y * dSinA;
+ point->y = point->x * dSinA + point->y * dCosA;
+ point->x = xTemp;
+
+ // back transform coordinates, if necessary
+ if( center.x ) point->x += center.x;
+ if( center.y ) point->y += center.y;
+ }
+ }
+}
+
+void wxDCBase::CalculateEllipticPoints( wxList* points,
+ wxCoord xStart, wxCoord yStart,
+ wxCoord w, wxCoord h,
+ double sa, double ea )
+{
+ double pi = 3.1415926535;
+ double sar = 0;
+ double ear = 0;
+ int xsa = 0;
+ int ysa = 0;
+ int xea = 0;
+ int yea = 0;
+ int sq = 0;
+ int eq = 0;
+ bool bUseAngles = false;
+ if( w<0 ) w = -w;
+ if( h<0 ) h = -h;
+ // half-axes
+ wxCoord a = w/2;
+ wxCoord b = h/2;
+ // decrement 1 pixel if ellipse is smaller than 2*a, 2*b
+ int decrX = 0;
+ if( 2*a == w ) decrX = 1;
+ int decrY = 0;
+ if( 2*b == h ) decrY = 1;
+ // center
+ wxCoord xCenter = xStart + a;
+ wxCoord yCenter = yStart + b;
+ // calculate data for start and end, if necessary
+ if( sa != ea )
+ {
+ bUseAngles = true;
+ // normalisation of angles
+ while( sa<0 ) sa += 360;
+ while( ea<0 ) ea += 360;
+ while( sa>=360 ) sa -= 360;
+ while( ea>=360 ) ea -= 360;
+ // calculate quadrant numbers
+ if( sa > 270 ) sq = 3;
+ else if( sa > 180 ) sq = 2;
+ else if( sa > 90 ) sq = 1;
+ if( ea > 270 ) eq = 3;
+ else if( ea > 180 ) eq = 2;
+ else if( ea > 90 ) eq = 1;
+ sar = sa * pi / 180.0;
+ ear = ea * pi / 180.0;
+ // correct angle circle -> ellipse
+ sar = atan( -a/(double)b * tan( sar ) );
+ if ( sq == 1 || sq == 2 ) sar += pi;
+ ear = atan( -a/(double)b * tan( ear ) );
+ if ( eq == 1 || eq == 2 ) ear += pi;
+ // coordinates of points
+ xsa = xCenter + a * cos( sar );
+ if( sq == 0 || sq == 3 ) xsa -= decrX;
+ ysa = yCenter + b * sin( sar );
+ if( sq == 2 || sq == 3 ) ysa -= decrY;
+ xea = xCenter + a * cos( ear );
+ if( eq == 0 || eq == 3 ) xea -= decrX;
+ yea = yCenter + b * sin( ear );
+ if( eq == 2 || eq == 3 ) yea -= decrY;
+ } // if iUseAngles
+ // calculate c1 = b^2, c2 = b^2/a^2 with a = w/2, b = h/2
+ double c1 = b * b;
+ double c2 = 2.0 / w;
+ c2 *= c2;
+ c2 *= c1;
+ wxCoord x = 0;
+ wxCoord y = b;
+ long x2 = 1;
+ long y2 = y*y;
+ long y2_old = 0;
+ long y_old = 0;
+ // Lists for quadrant 1 to 4
+ wxList pointsarray[4];
+ // Calculate points for first quadrant and set in all quadrants
+ for( x = 0; x <= a; ++x )
+ {
+ x2 = x2+x+x-1;
+ y2_old = y2;
+ y_old = y;
+ bool bNewPoint = false;
+ while( y2 > c1 - c2 * x2 && y > 0 )
+ {
+ bNewPoint = true;
+ y2 = y2-y-y+1;
+ --y;
+ }
+ // old y now to big: set point with old y, old x
+ if( bNewPoint && x>1)
+ {
+ int x1 = x - 1;
+ // remove points on the same line
+ pointsarray[0].Insert( (wxObject*) new wxPoint( xCenter + x1 - decrX, yCenter - y_old ) );
+ pointsarray[1].Append( (wxObject*) new wxPoint( xCenter - x1, yCenter - y_old ) );
+ pointsarray[2].Insert( (wxObject*) new wxPoint( xCenter - x1, yCenter + y_old - decrY ) );
+ pointsarray[3].Append( (wxObject*) new wxPoint( xCenter + x1 - decrX, yCenter + y_old - decrY ) );
+ } // set point
+ } // calculate point
+
+ // Starting and/or ending points for the quadrants, first quadrant gets both.
+ pointsarray[0].Insert( (wxObject*) new wxPoint( xCenter + a - decrX, yCenter ) );
+ pointsarray[0].Append( (wxObject*) new wxPoint( xCenter, yCenter - b ) );
+ pointsarray[1].Append( (wxObject*) new wxPoint( xCenter - a, yCenter ) );
+ pointsarray[2].Append( (wxObject*) new wxPoint( xCenter, yCenter + b - decrY ) );
+ pointsarray[3].Append( (wxObject*) new wxPoint( xCenter + a - decrX, yCenter ) );
+
+ // copy quadrants in original list
+ if( bUseAngles )
+ {
+ // Copy the right part of the points in the lists
+ // and delete the wxPoints, because they do not leave this method.
+ points->Append( (wxObject*) new wxPoint( xsa, ysa ) );
+ int q = sq;
+ bool bStarted = false;
+ bool bReady = false;
+ bool bForceTurn = ( sq == eq && sa > ea );
+ while( !bReady )
+ {
+ for( wxNode *node = pointsarray[q].First(); node; node = node->Next() )
+ {
+ // once: go to starting point in start quadrant
+ if( !bStarted &&
+ (
+ ( (wxPoint*) node->Data() )->x < xsa+1 && q <= 1
+ ||
+ ( (wxPoint*) node->Data() )->x > xsa-1 && q >= 2
+ )
+ )
+ {
+ bStarted = true;
+ }
+
+ // copy point, if not at ending point
+ if( bStarted )
+ {
+ if( q != eq || bForceTurn
+ ||
+ ( (wxPoint*) node->Data() )->x > xea+1 && q <= 1
+ ||
+ ( (wxPoint*) node->Data() )->x < xea-1 && q >= 2
+ )
+ {
+ // copy point
+ wxPoint* pPoint = new wxPoint( *((wxPoint*) node->Data() ) );
+ points->Append( (wxObject*) pPoint );
+ }
+ else if( q == eq && !bForceTurn || ( (wxPoint*) node->Data() )->x == xea)
+ {
+ bReady = true;
+ }
+ }
+ } // for node
+ ++q;
+ if( q > 3 ) q = 0;
+ bForceTurn = false;
+ bStarted = true;
+ } // while not bReady
+ points->Append( (wxObject*) new wxPoint( xea, yea ) );
+
+ // delete points
+ for( q = 0; q < 4; ++q )
+ {
+ for( wxNode *node = pointsarray[q].First(); node; node = node->Next() )
+ {
+ wxPoint *p = (wxPoint *)node->Data();
+ delete p;
+ }
+ }
+ }
+ else
+ {
+ // copy whole ellipse, wxPoints will be deleted outside
+ for( wxNode *node = pointsarray[0].First(); node; node = node->Next() )
+ {
+ wxObject *p = node->Data();
+ points->Append( p );
+ }
+ for( node = pointsarray[1].First(); node; node = node->Next() )
+ {
+ wxObject *p = node->Data();
+ points->Append( p );
+ }
+ for( node = pointsarray[2].First(); node; node = node->Next() )
+ {
+ wxObject *p = node->Data();
+ points->Append( p );
+ }
+ for( node = pointsarray[3].First(); node; node = node->Next() )
+ {
+ wxObject *p = node->Data();
+ points->Append( p );
+ }
+ } // not iUseAngles
+} // CalculateEllipticPoints
+
+#endif
+