From 2261baf7a458e8b02d40e1d92b81b69b54435808 Mon Sep 17 00:00:00 2001 From: Vadim Zeitlin Date: Thu, 21 Feb 2008 16:13:39 +0000 Subject: [PATCH] restore generic DrawEllipticArc() used by CE which was lost during the great wxDC refactoring somehow git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@51963 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775 --- include/wx/dc.h | 48 +++++++ src/common/dcbase.cpp | 315 ++++++++++++++++++++++++++++++++++++++++++ src/msw/dc.cpp | 4 +- 3 files changed, 365 insertions(+), 2 deletions(-) diff --git a/include/wx/dc.h b/include/wx/dc.h index ab3b1c9ccf..b94afb35c0 100644 --- a/include/wx/dc.h +++ b/include/wx/dc.h @@ -500,6 +500,54 @@ protected: m_clipX1 = m_clipX2 = m_clipY1 = m_clipY2 = 0; } +#ifdef __WXWINCE__ + //! Generic method to draw ellipses, circles and arcs with current pen and brush. + /*! \param x Upper left corner of bounding box. + * \param y Upper left corner of bounding box. + * \param w Width of bounding box. + * \param h Height of bounding box. + * \param sa Starting angle of arc + * (counterclockwise, start at 3 o'clock, 360 is full circle). + * \param ea Ending angle of arc. + * \param angle Rotation angle, the Arc will be rotated after + * calculating begin and end. + */ + void DrawEllipticArcRot( wxCoord x, wxCoord y, + wxCoord width, wxCoord height, + double sa = 0, double ea = 0, double angle = 0 ) + { DoDrawEllipticArcRot( x, y, width, height, sa, ea, angle ); } + + void DrawEllipticArcRot( const wxPoint& pt, + const wxSize& sz, + double sa = 0, double ea = 0, double angle = 0 ) + { DoDrawEllipticArcRot( pt.x, pt.y, sz.x, sz.y, sa, ea, angle ); } + + void DrawEllipticArcRot( const wxRect& rect, + double sa = 0, double ea = 0, double angle = 0 ) + { DoDrawEllipticArcRot( rect.x, rect.y, rect.width, rect.height, sa, ea, angle ); } + + virtual void DoDrawEllipticArcRot( wxCoord x, wxCoord y, + wxCoord w, wxCoord h, + double sa = 0, double ea = 0, double angle = 0 ); + + //! Rotates points around center. + /*! This is a quite straight method, it calculates in pixels + * and so it produces rounding errors. + * \param points The points inside will be rotated. + * \param angle Rotating angle (counterclockwise, start at 3 o'clock, 360 is full circle). + * \param center Center of rotation. + */ + void Rotate( wxPointList* points, double angle, wxPoint center = wxPoint(0,0) ); + + // used by DrawEllipticArcRot + // Careful: wxList gets filled with points you have to delete later. + void CalculateEllipticPoints( wxPointList* points, + wxCoord xStart, wxCoord yStart, + wxCoord w, wxCoord h, + double sa, double ea ); +#endif // __WXWINCE__ + + // window on which the DC draws or NULL wxWindow *m_window; diff --git a/src/common/dcbase.cpp b/src/common/dcbase.cpp index aea373f4ca..977c96637c 100644 --- a/src/common/dcbase.cpp +++ b/src/common/dcbase.cpp @@ -1339,3 +1339,318 @@ void wxDC::GetClippingBox(long *x, long *y, long *w, long *h) const } #endif // WXWIN_COMPATIBILITY_2_8 + +/* +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 wxDCImpl::DoDrawEllipticArcRot( wxCoord x, wxCoord y, + wxCoord w, wxCoord h, + double sa, double ea, double angle ) +{ + wxPointList 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( new wxPoint( x+w/2, y+h/2 ) ); + + // copy list into array and delete list elements + int n = list.GetCount(); + wxPoint *points = new wxPoint[n]; + int i = 0; + wxPointList::compatibility_iterator node; + for ( node = list.GetFirst(); node; node = node->GetNext(), i++ ) + { + wxPoint *point = node->GetData(); + 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 wxDCImpl::Rotate( wxPointList* points, double angle, wxPoint center ) +{ + if( angle != 0.0 ) + { + double pi(M_PI); + double dSinA = -sin(angle*2.0*pi/360.0); + double dCosA = cos(angle*2.0*pi/360.0); + wxPointList::compatibility_iterator node; + for ( node = points->GetFirst(); node; node = node->GetNext() ) + { + wxPoint* point = node->GetData(); + + // 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 wxDCImpl::CalculateEllipticPoints( wxPointList* points, + wxCoord xStart, wxCoord yStart, + wxCoord w, wxCoord h, + double sa, double ea ) +{ + double pi = M_PI; + 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 + wxPointList 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( new wxPoint( xCenter + x1 - decrX, yCenter - y_old ) ); + pointsarray[1].Append( new wxPoint( xCenter - x1, yCenter - y_old ) ); + pointsarray[2].Insert( new wxPoint( xCenter - x1, yCenter + y_old - decrY ) ); + pointsarray[3].Append( 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( new wxPoint( xCenter + a - decrX, yCenter ) ); + pointsarray[0].Append( new wxPoint( xCenter, yCenter - b ) ); + pointsarray[1].Append( new wxPoint( xCenter - a, yCenter ) ); + pointsarray[2].Append( new wxPoint( xCenter, yCenter + b - decrY ) ); + pointsarray[3].Append( 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( new wxPoint( xsa, ysa ) ); + int q = sq; + bool bStarted = false; + bool bReady = false; + bool bForceTurn = ( sq == eq && sa > ea ); + while( !bReady ) + { + wxPointList::compatibility_iterator node; + for( node = pointsarray[q].GetFirst(); node; node = node->GetNext() ) + { + // once: go to starting point in start quadrant + if( !bStarted && + ( + node->GetData()->x < xsa+1 && q <= 1 + || + node->GetData()->x > xsa-1 && q >= 2 + ) + ) + { + bStarted = true; + } + + // copy point, if not at ending point + if( bStarted ) + { + if( q != eq || bForceTurn + || + ( (wxPoint*) node->GetData() )->x > xea+1 && q <= 1 + || + ( (wxPoint*) node->GetData() )->x < xea-1 && q >= 2 + ) + { + // copy point + wxPoint* pPoint = new wxPoint( *(node->GetData()) ); + points->Append( pPoint ); + } + else if( q == eq && !bForceTurn || node->GetData()->x == xea) + { + bReady = true; + } + } + } // for node + ++q; + if( q > 3 ) q = 0; + bForceTurn = false; + bStarted = true; + } // while not bReady + points->Append( new wxPoint( xea, yea ) ); + + // delete points + for( q = 0; q < 4; ++q ) + { + wxPointList::compatibility_iterator node; + for( node = pointsarray[q].GetFirst(); node; node = node->GetNext() ) + { + wxPoint *p = node->GetData(); + delete p; + } + } + } + else + { + wxPointList::compatibility_iterator node; + // copy whole ellipse, wxPoints will be deleted outside + for( node = pointsarray[0].GetFirst(); node; node = node->GetNext() ) + { + wxPoint *p = node->GetData(); + points->Append( p ); + } + for( node = pointsarray[1].GetFirst(); node; node = node->GetNext() ) + { + wxPoint *p = node->GetData(); + points->Append( p ); + } + for( node = pointsarray[2].GetFirst(); node; node = node->GetNext() ) + { + wxPoint *p = node->GetData(); + points->Append( p ); + } + for( node = pointsarray[3].GetFirst(); node; node = node->GetNext() ) + { + wxPoint *p = node->GetData(); + points->Append( p ); + } + } // not iUseAngles +} // CalculateEllipticPoints + +#endif // __WXWINCE__ diff --git a/src/msw/dc.cpp b/src/msw/dc.cpp index e8bea67baa..3eeafd8e5d 100644 --- a/src/msw/dc.cpp +++ b/src/msw/dc.cpp @@ -857,7 +857,7 @@ wxMSWDCImpl::DoDrawPolyPolygon(int n, int fillStyle) { #ifdef __WXWINCE__ - wxDCBase::DoDrawPolyPolygon(n, count, points, xoffset, yoffset, fillStyle); + wxDCImpl::DoDrawPolyPolygon(n, count, points, xoffset, yoffset, fillStyle); #else WXMICROWIN_CHECK_HDC @@ -1015,7 +1015,7 @@ void wxMSWDCImpl::DoDrawSpline(const wxPointList *points) { #ifdef __WXWINCE__ // WinCE does not support ::PolyBezier so use generic version - wxDCBase::DoDrawSpline(points); + wxDCImpl::DoDrawSpline(points); #else // quadratic b-spline to cubic bezier spline conversion // -- 2.45.2