kicad/common/gr_basic.cpp

/********************************/
/* Low level graphics routines  */
/********************************/


#include <fctsys.h>
#include <gr_basic.h>
#include <common.h>
#include <trigo.h>
#include <macros.h>
#include <base_struct.h>
#include <class_base_screen.h>
#include <bezier_curves.h>
#include <math_for_graphics.h>
#include <wx/graphics.h>

static const bool FILLED = true;

/* Important Note:
 * These drawing functions  clip draw item before send these items to wxDC draw
 * functions.  For guy who asks why i did it, see a sample of problems encountered
 * when pixels
 * coordinates overflow 16 bits values:
 * http://trac.wxwidgets.org/ticket/10446
 * Problems can be found under Windows **and** Linux (mainly when drawing arcs)
 * (mainly at low zoom values (2, 1 or 0.5), in Pcbnew)
 * some of these problems could be now fixed in recent distributions.
 *
 * Currently (feb 2009) there are overflow problems when drawing solid (filled)
 * polygons under linux without clipping
 *
 * So before removing clipping functions, be aware these bug (they are not in
 * KiCad or wxWidgets) are fixed by testing how are drawn complex lines arcs
 * and solid polygons under Windows and Linux and remember users can have old
 * versions with bugs
 */


/* Definitions for enabling and disabling debugging features in gr_basic.cpp.
 * Please remember to set these back to 0 before making LAUNCHPAD commits.
 */
#define DEBUG_DUMP_CLIP_ERROR_COORDS 0  // Set to 1 to dump clip algorithm errors.
#define DEBUG_DUMP_CLIP_COORDS       0  // Set to 1 to dump clipped coordinates.


// For draw mode = XOR GR_XOR or GR_NXOR by background color
GR_DRAWMODE g_XorMode = GR_NXOR;

// Background color of the design frame
EDA_COLOR_T g_DrawBgColor = WHITE;


#define USE_CLIP_FILLED_POLYGONS

#ifdef USE_CLIP_FILLED_POLYGONS
static void ClipAndDrawFilledPoly( EDA_RECT * ClipBox, wxDC * DC, wxPoint Points[], int n );
#endif

/* These functions are used by corresponding functions
 * ( GRSCircle is called by GRCircle for instance) after mapping coordinates
 * from user units to screen units(pixels coordinates)
 */
static void GRSRect( EDA_RECT* aClipBox, wxDC* aDC, int x1, int y1,
                     int x2, int y2, int aWidth, EDA_COLOR_T aColor,
                     wxPenStyle aStyle = wxPENSTYLE_SOLID );

/**/

static int          GRLastMoveToX, GRLastMoveToY;
static bool         s_ForceBlackPen;   /* if true: draws in black instead of
                                        * color for printing. */
static int          xcliplo = 0,
                    ycliplo = 0,
                    xcliphi = 2000,
                    ycliphi = 2000;

static EDA_COLOR_T   s_DC_lastcolor = UNSPECIFIED_COLOR;
static int   s_DC_lastwidth = -1;
static int   s_DC_lastpenstyle   = -1;
static EDA_COLOR_T   s_DC_lastbrushcolor = UNSPECIFIED_COLOR;
static bool  s_DC_lastbrushfill  = false;
static wxDC* s_DC_lastDC = NULL;


/**
 * Test if any part of a line falls within the bounds of a rectangle.
 *
 * Please note that this is only accurate for lines that are one pixel wide.
 *
 * @param aClipBox - The rectangle to test.
 * @param x1 - X coordinate of one end of a line.
 * @param y1 - Y coordinate of one end of a line.
 * @param x2 - X coordinate of the other end of a line.
 * @param y2 - Y coordinate of the other  end of a line.
 *
 * @return - False if any part of the line lies within the rectangle.
 */
static bool clipLine( EDA_RECT* aClipBox, int& x1, int& y1, int& x2, int& y2 )
{
    if( aClipBox->Contains( x1, y1 ) && aClipBox->Contains( x2, y2 ) )
        return false;

    wxRect rect = *aClipBox;
    int    minX = rect.GetLeft();
    int    maxX = rect.GetRight();
    int    minY = rect.GetTop();
    int    maxY = rect.GetBottom();
    int    clippedX, clippedY;

#if DEBUG_DUMP_CLIP_COORDS
    int    tmpX1, tmpY1, tmpX2, tmpY2;
    tmpX1 = x1;
    tmpY1 = y1;
    tmpX2 = x2;
    tmpY2 = y2;
#endif

    if( aClipBox->Contains( x1, y1 ) )
    {
        if( x1 == x2 )         /* Vertical line, clip Y. */
        {
            if( y2 < minY )
            {
                y2 = minY;
                return false;
            }

            if( y2 > maxY )
            {
                y2 = maxY;
                return false;
            }
        }
        else if( y1 == y2 )    /* Horizontal line, clip X. */
        {
            if( x2 < minX )
            {
                x2 = minX;
                return false;
            }

            if( x2 > maxX )
            {
                x2 = maxX;
                return false;
            }
        }

        /* If we're here, it's a diagonal line. */

        if( TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, minY, minX, maxY,
                                                       &clippedX, &clippedY )       /* Left */
           || TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, minY, maxX, minY,
                                                         &clippedX, &clippedY )     /* Top */
           || TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, maxX, minY, maxX, maxY,
                                                         &clippedX, &clippedY )     /* Right */
           || TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, maxY, maxX, maxY,
                                                         &clippedX, &clippedY ) )   /* Bottom */
        {
            if( x2 != clippedX )
                x2 = clippedX;
            if( y2 != clippedY )
                y2 = clippedY;
            return false;
        }

        /* If we're here, something has gone terribly wrong. */
#if DEBUG_DUMP_CLIP_ERROR_COORDS
        wxLogDebug( wxT( "Line (%d,%d):(%d,%d) in rectangle (%d,%d,%d,%d) clipped to (%d,%d,%d,%d)" ),
                    tmpX1, tmpY1, tmpX2, tmpY2, minX, minY, maxX, maxY, x1, y1, x2, y2 );
#endif
        return false;
    }
    else if( aClipBox->Contains( x2, y2 ) )
    {
        if( x1 == x2 )         /* Vertical line, clip Y. */
        {
            if( y2 < minY )
            {
                y2 = minY;
                return false;
            }

            if( y2 > maxY )
            {
                y2 = maxY;
                return false;
            }
        }
        else if( y1 == y2 )    /* Horizontal line, clip X. */
        {
            if( x2 < minX )
            {
                x2 = minX;
                return false;
            }

            if( x2 > maxX )
            {
                x2 = maxX;
                return false;
            }
        }

        if( TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, minY, minX, maxY,
                                                       &clippedX, &clippedY )       /* Left */
           || TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, minY, maxX, minY,
                                                         &clippedX, &clippedY )     /* Top */
           || TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, maxX, minY, maxX, maxY,
                                                         &clippedX, &clippedY )     /* Right */
           || TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, maxY, maxX, maxY,
                                                         &clippedX, &clippedY ) )   /* Bottom */
        {
            if( x1 != clippedX )
                x1 = clippedX;
            if( y1 != clippedY )
                y1 = clippedY;
            return false;
        }

        /* If we're here, something has gone terribly wrong. */
#if DEBUG_DUMP_CLIP_ERROR_COORDS
        wxLogDebug( wxT( "Line (%d,%d):(%d,%d) in rectangle (%d,%d,%d,%d) clipped to (%d,%d,%d,%d)" ),
                    tmpX1, tmpY1, tmpX2, tmpY2, minX, minY, maxX, maxY, x1, y1, x2, y2 );
#endif
        return false;
    }
    else
    {
        int* intersectX;
        int* intersectY;
        int  intersectX1, intersectY1, intersectX2, intersectY2;
        bool haveFirstPoint = false;

        intersectX = &intersectX1;
        intersectY = &intersectY1;

        /* Left clip rectangle line. */
        if( TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, minY, minX, maxY,
                                                       intersectX, intersectY ) )
        {
            intersectX     = &intersectX2;
            intersectY     = &intersectY2;
            haveFirstPoint = true;
        }

        /* Top clip rectangle line. */
        if( TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, minY, maxX, minY,
                                                       intersectX, intersectY ) )
        {
            intersectX = &intersectX2;
            intersectY = &intersectY2;
            if( haveFirstPoint )
            {
                x1 = intersectX1;
                y1 = intersectY1;
                x2 = intersectX2;
                y2 = intersectY2;
                return false;
            }
            haveFirstPoint = true;
        }

        /* Right clip rectangle line. */
        if( TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, maxX, minY, maxX, maxY,
                                                       intersectX, intersectY ) )
        {
            intersectX = &intersectX2;
            intersectY = &intersectY2;
            if( haveFirstPoint )
            {
                x1 = intersectX1;
                y1 = intersectY1;
                x2 = intersectX2;
                y2 = intersectY2;
                return false;
            }
            haveFirstPoint = true;
        }

        /* Bottom clip rectangle line. */
        if( TestForIntersectionOfStraightLineSegments( x1, y1, x2, y2, minX, maxY, maxX, maxY,
                                                       intersectX, intersectY ) )
        {
            intersectX = &intersectX2;
            intersectY = &intersectY2;
            if( haveFirstPoint )
            {
                x1 = intersectX1;
                y1 = intersectY1;
                x2 = intersectX2;
                y2 = intersectY2;
                return false;
            }
        }

        /* If we're here and only one line of the clip box has been intersected,
         * something has gone terribly wrong. */
#if DEBUG_DUMP_CLIP_ERROR_COORDS
        if( haveFirstPoint )
            wxLogDebug( wxT( "Line (%d,%d):(%d,%d) in rectangle (%d,%d,%d,%d) clipped to (%d,%d,%d,%d)" ),
                        tmpX1, tmpY1, tmpX2, tmpY2, minX, minY, maxX, maxY, x1, y1, x2, y2 );
#endif
    }

    /* Set this to one to verify that diagonal lines get clipped properly. */
#if DEBUG_DUMP_CLIP_COORDS
    if( !( x1 == x2 || y1 == y2 ) )
        wxLogDebug( wxT( "Clipped line (%d,%d):(%d,%d) from rectangle (%d,%d,%d,%d)" ),
                    tmpX1, tmpY1, tmpX2, tmpY2, minX, minY, maxX, maxY );
#endif

    return true;
}


static void WinClipAndDrawLine( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
                                EDA_COLOR_T Color, int width = 1 )
{
    GRLastMoveToX = x2;
    GRLastMoveToY = y2;

    if( ClipBox )
    {
        EDA_RECT clipbox(*ClipBox);
        clipbox.Inflate(width/2);
        if( clipLine( &clipbox, x1, y1, x2, y2 ) )
            return;
    }

    GRSetColorPen( DC, Color, width );
    DC->DrawLine( x1, y1, x2, y2 );
}


/* Forcing a reset of the current pen.
 * Must be called after changing the graphical device before any trace.
 */
void GRResetPenAndBrush( wxDC* DC )
{
    GRSetBrush( DC, BLACK );  // Force no fill
    s_DC_lastbrushcolor = UNSPECIFIED_COLOR;
    s_DC_lastcolor =  UNSPECIFIED_COLOR;
    s_DC_lastDC    = NULL;
}


/**
 * Function GRSetColorPen
 * sets a pen style, width, color, and alpha into the given device context.
 */
void GRSetColorPen( wxDC* DC, EDA_COLOR_T Color, int width, wxPenStyle style )
{
    if( width < 0 )
        width = 0;

#ifdef __WXMAC__
    // Under OSX when wxPen is set to 0, cocoa follows the request drawing nothing &
    // in the bitmap world the minimum is enough to light a pixel, in vectorial one not
    if( width <= 1 )
        width = DC->DeviceToLogicalXRel( 1 );
#endif

    if( s_ForceBlackPen )
    {
        Color = BLACK;
    }

    if(   s_DC_lastcolor != Color
       || s_DC_lastwidth != width
       || s_DC_lastpenstyle != style
       || s_DC_lastDC != DC  )
    {
        wxPen    pen;

        wxColour wx_color = MakeColour( Color );

        pen.SetColour( wx_color );
        pen.SetWidth( width );
        pen.SetStyle( style );

        DC->SetPen( pen );

        s_DC_lastcolor    = Color;
        s_DC_lastwidth    = width;
        s_DC_lastpenstyle = style;
        s_DC_lastDC = DC;
    }
}


void GRSetBrush( wxDC* DC, EDA_COLOR_T Color, bool fill )
{
    if( s_ForceBlackPen )
        Color = BLACK;

    if(   s_DC_lastbrushcolor != Color
       || s_DC_lastbrushfill  != fill
       || s_DC_lastDC != DC  )
    {
        wxBrush DrawBrush;
        DrawBrush.SetColour( MakeColour( Color ) );

        if( fill )
            DrawBrush.SetStyle( wxSOLID );
        else
            DrawBrush.SetStyle( wxTRANSPARENT );

        DC->SetBrush( DrawBrush );

        s_DC_lastbrushcolor = Color;
        s_DC_lastbrushfill  = fill;
        s_DC_lastDC = DC;
    }
}


/**
 * Function GRForceBlackPen
 * @param flagforce True to force a black pen whenever the asked color
 */
void GRForceBlackPen( bool flagforce )
{
    s_ForceBlackPen = flagforce;
}


/**
 * Function GetGRForceBlackPenState
 * @return s_ForceBlackPen (True if  a black pen was forced)
 */
bool GetGRForceBlackPenState( void )
{
    return s_ForceBlackPen;
}


/*************************************/
/* Set the device context draw mode. */
/*************************************/
void GRSetDrawMode( wxDC* DC, GR_DRAWMODE draw_mode )
{
    if( draw_mode & GR_OR )
#if defined(__WXMAC__) && (wxMAC_USE_CORE_GRAPHICS || wxCHECK_VERSION( 2, 9, 0 ) )

        DC->SetLogicalFunction( wxCOPY );
#elif defined( USE_WX_GRAPHICS_CONTEXT )

        DC->SetLogicalFunction( wxCOPY );
#else

        DC->SetLogicalFunction( wxOR );
#endif
    else if( draw_mode & GR_XOR )
#if defined( USE_WX_GRAPHICS_CONTEXT )

        DC->SetLogicalFunction( wxCOPY );
#else

        DC->SetLogicalFunction( wxXOR );
#endif
    else if( draw_mode & GR_NXOR )
#if defined(__WXMAC__) && (wxMAC_USE_CORE_GRAPHICS || wxCHECK_VERSION( 2, 9, 0 ) )

        DC->SetLogicalFunction( wxXOR );
#elif defined( USE_WX_GRAPHICS_CONTEXT )

        DC->SetLogicalFunction( wxCOPY );
#else

        DC->SetLogicalFunction( wxEQUIV );
#endif
    else if( draw_mode & GR_INVERT )
#if defined( USE_WX_GRAPHICS_CONTEXT )

        DC->SetLogicalFunction( wxCOPY );
#else

        DC->SetLogicalFunction( wxINVERT );
#endif
    else
        DC->SetLogicalFunction( wxCOPY );

#ifdef USE_WX_OVERLAY
    DC->SetLogicalFunction( wxCOPY );
#endif
}


void GRPutPixel( EDA_RECT* ClipBox, wxDC* DC, int x, int y, EDA_COLOR_T Color )
{
    if( ClipBox && !ClipBox->Contains( x, y ) )
        return;

    GRSetColorPen( DC, Color );
    DC->DrawPoint( x, y );
}


/*
 * Draw a line, in object space.
 */
void GRLine( EDA_RECT* ClipBox,
             wxDC*     DC,
             int       x1,
             int       y1,
             int       x2,
             int       y2,
             int       width,
             EDA_COLOR_T       Color )
{
    WinClipAndDrawLine( ClipBox, DC, x1, y1, x2, y2, Color, width );
    GRLastMoveToX = x2;
    GRLastMoveToY = y2;
}


void GRLine( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aStart, wxPoint aEnd, int aWidth, EDA_COLOR_T aColor )
{
    GRLine( aClipBox, aDC, aStart.x, aStart.y, aEnd.x, aEnd.y, aWidth, aColor );
}


void GRDashedLineTo( EDA_RECT* ClipBox, wxDC* DC, int x2, int y2, int width, EDA_COLOR_T Color )
{
    s_DC_lastcolor = UNSPECIFIED_COLOR;
    GRSetColorPen( DC, Color, width, wxPENSTYLE_SHORT_DASH );
    GRLine( ClipBox, DC, GRLastMoveToX, GRLastMoveToY, x2, y2, width, Color );
    s_DC_lastcolor = UNSPECIFIED_COLOR;
    GRSetColorPen( DC, Color, width );
    GRLastMoveToX = x2;
    GRLastMoveToY = y2;
}


void GRDashedLine( EDA_RECT* ClipBox,
                   wxDC*     DC,
                   int       x1,
                   int       y1,
                   int       x2,
                   int       y2,
                   int       width,
                   EDA_COLOR_T Color )
{
    GRLastMoveToX  = x2;
    GRLastMoveToY  = y2;
    s_DC_lastcolor = UNSPECIFIED_COLOR;
    GRSetColorPen( DC, Color, width, wxPENSTYLE_SHORT_DASH );
    GRLine( ClipBox, DC, x1, y1, x2, y2, width, Color );
    s_DC_lastcolor = UNSPECIFIED_COLOR;
    GRSetColorPen( DC, Color, width );
}


/*
 * Move to a new position, in object space.
 */
void GRMoveTo( int x, int y )
{
    GRLastMoveToX = x;
    GRLastMoveToY = y;
}


/*
 * Draw line to a new position, in object space.
 */
void GRLineTo( EDA_RECT* ClipBox, wxDC* DC, int x, int y, int width, EDA_COLOR_T Color )
{
    int GRLineToX, GRLineToY;

    GRLineToX = x;
    GRLineToY = y;

    GRLine( ClipBox, DC, GRLastMoveToX, GRLastMoveToY, GRLineToX, GRLineToY, width, Color );
}


void GRMixedLine( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
                  int width, EDA_COLOR_T Color )
{
    GRSetColorPen( DC, Color, width, wxPENSTYLE_DOT_DASH );
    GRLine( ClipBox, DC, x1, y1, x2, y2, width, Color );
    GRSetColorPen( DC, Color, width );
}



/**
 * Function GRLineArray
 * draws an array of lines (not a polygon).
 * @param aClipBox = the clip box
 * @param aDC = the device context into which drawing should occur.
 * @param aLines = a list of pair of coordinate in user space: a pair for each line.
 * @param aWidth = the width of each line.
 * @param aColor = an index into our color table of RGB colors.
 * @see EDA_COLOR_T and colors.h
 */
void GRLineArray( EDA_RECT* aClipBox, wxDC* aDC, std::vector<wxPoint>& aLines,
                  int aWidth, EDA_COLOR_T aColor )
{
    GRSetColorPen( aDC, aColor, aWidth );

#if defined( USE_WX_GRAPHICS_CONTEXT ) || defined(__WXMAC__)
    wxGraphicsContext* gc = wxGraphicsContext::Create( aDC );
    wxASSERT( gc );
    gc->Clip( aClipBox->GetX(), aClipBox->GetY(), aClipBox->GetRight(), aClipBox->GetHeight() );
    wxGraphicsPath     path = gc->CreatePath();

    for( unsigned i = 0; i < aLines.size(); )
    {
        path.MoveToPoint( aLines[i].x, aLines[i].y );
        i++;
        path.AddLineToPoint( aLines[i].x, aLines[i].y );
        i++;
    }

    gc->StrokePath( path );
    gc->ResetClip();
    delete gc;
#else

    if( aClipBox )
        aClipBox->Inflate(aWidth/2);
    for( unsigned i = 0; i < aLines.size(); i += 2)
    {
        int x1 = aLines[i].x;
        int y1 = aLines[i].y;
        int x2 = aLines[i+1].x;
        int y2 = aLines[i+1].y;
        GRLastMoveToX = x2;
        GRLastMoveToY = y2;
        if( ( aClipBox == NULL ) || !clipLine( aClipBox, x1, y1, x2, y2 ) )
            aDC->DrawLine( x1, y1, x2, y2 );
    }
    if( aClipBox )
        aClipBox->Inflate(-aWidth/2);
#endif
}


void GRCSegm( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
              int width, int aPenSize, EDA_COLOR_T Color )
{
    long radius;
    int  dwx, dwy;
    long dx, dy, dwx2, dwy2;
    long sx1, sy1, ex1, ey1;
    long sx2, sy2, ex2, ey2;
    bool swap_ends = false;


    GRLastMoveToX = x2;
    GRLastMoveToY = y2;

    if( ClipBox )
    {
        EDA_RECT clipbox(*ClipBox);
        clipbox.Inflate(width/2);

        if( clipLine( &clipbox, x1, y1, x2, y2 ) )
            return;
    }


    if( width <= 2 )   /*  single line or 2 pixels */
    {
        GRSetColorPen( DC, Color, width );
        DC->DrawLine( x1, y1, x2, y2 );
        return;
    }

    GRSetColorPen( DC, Color, aPenSize );
    GRSetBrush( DC, Color, false );

    radius = (width + 1) >> 1;

    dx = x2 - x1;
    dy = y2 - y1;

    if( dx == 0 )  /* segment vertical */
    {
        dwx = radius;
        if( dy >= 0 )
            dwx = -dwx;

        sx1 = x1 - dwx;
        sy1 = y1;

        ex1 = x2 - dwx;
        ey1 = y2;

        DC->DrawLine( sx1, sy1, ex1, ey1 );

        sx2 = x1 + dwx;
        sy2 = y1;

        ex2 = x2 + dwx;
        ey2 = y2;

        DC->DrawLine( sx2, sy2, ex2, ey2 );
    }
    else if( dy == 0 ) /* segment horizontal */
    {
        dwy = radius;
        if( dx < 0 )
            dwy = -dwy;

        sx1 = x1;
        sy1 = y1 - dwy;

        ex1 = x2;
        ey1 = y2 - dwy;

        DC->DrawLine( sx1, sy1, ex1, ey1 );

        sx2 = x1;
        sy2 = y1 + dwy;

        ex2 = x2;
        ey2 = y2 + dwy;

        DC->DrawLine( sx2, sy2, ex2, ey2 );
    }
    else
    {
        if( std::abs( dx ) == std::abs( dy ) )  // segment 45 degrees
        {
            dwx = dwy = ( (width * 5) + 4 ) / 7;    // = width / 2 * 0.707
            if( dy < 0 )
            {
                if( dx <= 0 )
                {
                    dwx = -dwx; swap_ends = true;
                }
            }
            else    // dy >= 0
            {
                if( dx > 0 )
                {
                    dwy = -dwy; swap_ends = true;
                }
                else
                    swap_ends = true;
            }
        }
        else
        {
            double delta_angle = ArcTangente( dy, dx );
            dwx = 0;
            dwy = width;
            RotatePoint( &dwx, &dwy, -delta_angle );
        }
        dwx2 = dwx >> 1;
        dwy2 = dwy >> 1;

        sx1 = x1 - dwx2;
        sy1 = y1 - dwy2;

        ex1 = x2 - dwx2;
        ey1 = y2 - dwy2;

        DC->DrawLine( sx1, sy1, ex1, ey1 );

        sx2 = x1 + dwx2;
        sy2 = y1 + dwy2;

        ex2 = x2 + dwx2;
        ey2 = y2 + dwy2;

        DC->DrawLine( sx2, sy2, ex2, ey2 );
    }

    if( swap_ends )
    {
        DC->DrawArc( sx2, sy2, sx1, sy1, x1, y1 );
        DC->DrawArc( ex1, ey1, ex2, ey2, x2, y2 );
    }
    else
    {
        DC->DrawArc( sx1, sy1, sx2, sy2, x1, y1 );
        DC->DrawArc( ex2, ey2, ex1, ey1, x2, y2 );
    }
}


void GRCSegm( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
              int width, EDA_COLOR_T Color )
{
    GRCSegm( ClipBox, DC, x1, y1, x2, y2, width, 0, Color );
}


void GRCSegm( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aStart, wxPoint aEnd,
              int aWidth, EDA_COLOR_T aColor )
{
    GRCSegm( aClipBox, aDC, aStart.x, aStart.y, aEnd.x, aEnd.y, aWidth, 0, aColor );
}


/*
 * Draw segment (full) with rounded ends in object space (real coords.).
 */
void GRFillCSegm( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
                  int width, EDA_COLOR_T Color )
{
    WinClipAndDrawLine( ClipBox, DC, x1, y1, x2, y2, Color, width );
}


void GRFilledSegment( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aStart, wxPoint aEnd,
                      int aWidth, EDA_COLOR_T aColor )
{
    WinClipAndDrawLine( aClipBox, aDC, aStart.x, aStart.y, aEnd.x, aEnd.y, aColor, aWidth );
}


static bool IsGRSPolyDrawable( EDA_RECT* ClipBox, int n, wxPoint Points[] )
{
    if( !ClipBox )
        return true;

    if( n <= 0 )
        return false;

    int Xmin, Xmax, Ymin, Ymax;

    Xmin = Xmax = Points[0].x;
    Ymin = Ymax = Points[0].y;

    for( int ii = 1; ii < n; ii++ )     // calculate rectangle
    {
        Xmin = std::min( Xmin, Points[ii].x );
        Xmax = std::max( Xmax, Points[ii].x );
        Ymin = std::min( Ymin, Points[ii].y );
        Ymax = std::max( Ymax, Points[ii].y );
    }

    xcliplo = ClipBox->GetX();
    ycliplo = ClipBox->GetY();
    xcliphi = ClipBox->GetRight();
    ycliphi = ClipBox->GetBottom();

    if( Xmax < xcliplo )
        return false;
    if( Xmin > xcliphi )
        return false;
    if( Ymax < ycliplo )
        return false;
    if( Ymin > ycliphi )
        return false;

    return true;
}


/*
 * Draw a new polyline and fill it if Fill, in screen space.
 */
static void GRSPoly( EDA_RECT* ClipBox,
                     wxDC*     DC,
                     int       n,
                     wxPoint   Points[],
                     bool      Fill,
                     int       width,
                     EDA_COLOR_T       Color,
                     EDA_COLOR_T       BgColor )
{
    if( !IsGRSPolyDrawable( ClipBox, n, Points ) )
        return;

    GRSetColorPen( DC, Color, width );

    if( Fill && ( n > 2 ) )
    {
        GRSetBrush( DC, BgColor, FILLED );


        /* clip before send the filled polygon to wxDC, because under linux
         * (GTK?) polygons having large coordinates are incorrectly drawn
         */
#ifdef USE_CLIP_FILLED_POLYGONS
        ClipAndDrawFilledPoly( ClipBox, DC, Points, n );
#else
        DC->DrawPolygon( n, Points );  // does not work very well under linux
#endif
    }
    else
    {
        wxPoint endPt = Points[n - 1];

        GRSetBrush( DC, Color );
        DC->DrawLines( n, Points );

        // The last point is not drawn by DrawLine and DrawLines
        // Add it if the polygon is not closed
        if( endPt != Points[0] )
            DC->DrawPoint( endPt.x, endPt.y );
    }
}


/*
 * Draw a new closed polyline and fill it if Fill, in screen space.
 */
static void GRSClosedPoly( EDA_RECT* ClipBox,
                           wxDC*     DC,
                           int       aPointCount,
                           wxPoint   aPoints[],
                           bool      Fill,
                           int       width,
                           EDA_COLOR_T       Color,
                           EDA_COLOR_T       BgColor )
{
    if( !IsGRSPolyDrawable( ClipBox, aPointCount, aPoints ) )
        return;

    GRSetColorPen( DC, Color, width );

    if( Fill && ( aPointCount > 2 ) )
    {
        GRLastMoveToX = aPoints[aPointCount - 1].x;
        GRLastMoveToY = aPoints[aPointCount - 1].y;
        GRSetBrush( DC, BgColor, FILLED );
#ifdef USE_CLIP_FILLED_POLYGONS
        ClipAndDrawFilledPoly( ClipBox, DC, aPoints, aPointCount );
#else
        DC->DrawPolygon( aPointCount, aPoints );  // does not work very well under linux
#endif
    }
    else
    {
        GRSetBrush( DC, BgColor );
        DC->DrawLines( aPointCount, aPoints );

        /* Close the polygon. */
        if( aPoints[aPointCount - 1] != aPoints[0] )
        {
            GRLine( ClipBox,
                    DC,
                    aPoints[0].x,
                    aPoints[0].y,
                    aPoints[aPointCount - 1].x,
                    aPoints[aPointCount - 1].y,
                    width,
                    Color );
        }
    }
}


/*
 * Draw a new polyline and fill it if Fill, in drawing space.
 */
void GRPoly( EDA_RECT* ClipBox, wxDC* DC, int n, wxPoint Points[],
             bool Fill, int width, EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    GRSPoly( ClipBox, DC, n, Points, Fill, width, Color, BgColor );
}


/*
 * Draw a closed polyline and fill it if Fill, in object space.
 */
void GRClosedPoly( EDA_RECT* ClipBox, wxDC* DC, int n, wxPoint Points[],
                   bool Fill, EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    GRClosedPoly( ClipBox, DC, n, Points, Fill, 0, Color, BgColor );
}


void GRClosedPoly( EDA_RECT* ClipBox, wxDC* DC, int n, wxPoint Points[],
                   bool Fill, int width, EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    GRSClosedPoly( ClipBox, DC, n, Points, Fill, width, Color, BgColor );
}


void GRCircle( EDA_RECT* ClipBox, wxDC* DC, int xc, int yc, int r, int width, EDA_COLOR_T Color )
{
    /* Clip circles off screen. */
    if( ClipBox )
    {
        int x0, y0, xm, ym;
        x0 = ClipBox->GetX();
        y0 = ClipBox->GetY();
        xm = ClipBox->GetRight();
        ym = ClipBox->GetBottom();

        if( xc < ( x0 - r - width ) )
            return;

        if( yc < ( y0 - r - width ) )
            return;

        if( xc > ( r + xm + width ) )
            return;

        if( yc > ( r + ym + width ) )
            return;
    }

    GRSetColorPen( DC, Color, width );
    GRSetBrush( DC, Color, false );
    DC->DrawEllipse( xc - r, yc - r, r + r, r + r );
}


void GRCircle( EDA_RECT* ClipBox, wxDC* DC, int x, int y, int r, EDA_COLOR_T Color )
{
    GRCircle( ClipBox, DC, x, y, r, 0, Color );
}


void GRCircle( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aPos, int aRadius, int aWidth, EDA_COLOR_T aColor )
{
    GRCircle( aClipBox, aDC, aPos.x, aPos.y, aRadius, aWidth, aColor );
}


void GRFilledCircle( EDA_RECT* ClipBox, wxDC* DC, int x, int y, int r,
                     int width, EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    /* Clip circles off screen. */
    if( ClipBox )
    {
        int x0, y0, xm, ym;
        x0 = ClipBox->GetX();
        y0 = ClipBox->GetY();
        xm = ClipBox->GetRight();
        ym = ClipBox->GetBottom();
        if( x < (x0 - r) )
            return;
        if( y < (y0 - r) )
            return;
        if( x > (r + xm) )
            return;
        if( y > (r + ym) )
            return;
    }

    GRSetColorPen( DC, Color, width );
    GRSetBrush( DC, BgColor, FILLED );
    DC->DrawEllipse( x - r, y - r, r + r, r + r );
}


void GRFilledCircle( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aPos, int aRadius, EDA_COLOR_T aColor )
{
    GRFilledCircle( aClipBox, aDC, aPos.x, aPos.y, aRadius, 0, aColor, aColor );
}


/*
 * Draw an arc in user space.
 */
void GRArc1( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
             int xc, int yc, EDA_COLOR_T Color )
{
    GRArc1( ClipBox, DC, x1, y1, x2, y2, xc, yc, 0, Color );
}


/*
 * Draw an arc, width = width in user space.
 */
void GRArc1( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
             int xc, int yc, int width, EDA_COLOR_T Color )
{
    /* Clip arcs off screen. */
    if( ClipBox )
    {
        int x0, y0, xm, ym, r;
        x0 = ClipBox->GetX();
        y0 = ClipBox->GetY();
        xm = ClipBox->GetRight();
        ym = ClipBox->GetBottom();
        r  = KiROUND( Distance( x1, y1, xc, yc ) );
        if( xc < ( x0 - r ) )
            return;
        if( yc < ( y0 - r ) )
            return;
        if( xc > ( r + xm ) )
            return;
        if( yc > ( r + ym ) )
            return;
    }

    GRSetColorPen( DC, Color, width );
    GRSetBrush( DC, Color );
    DC->DrawArc( x1, y1, x2, y2, xc, yc );
}


void GRArc1( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aStart, wxPoint aEnd,
             wxPoint aCenter, int aWidth, EDA_COLOR_T aColor )
{
    GRArc1( aClipBox, aDC, aStart.x, aStart.y, aEnd.x, aEnd.y, aCenter.x, aCenter.y,
            aWidth, aColor );
}


/*
 * Draw a filled arc in drawing space.
 */
void GRFilledArc( EDA_RECT* ClipBox,
                  wxDC*     DC,
                  int       x,
                  int       y,
                  double    StAngle,
                  double    EndAngle,
                  int       r,
                  int       width,
                  EDA_COLOR_T       Color,
                  EDA_COLOR_T       BgColor )
{
    int x1, y1, x2, y2;

    /* Clip arcs off screen */
    if( ClipBox )
    {
        int x0, y0, xm, ym;
        x0 = ClipBox->GetX();
        y0 = ClipBox->GetY();
        xm = ClipBox->GetRight();
        ym = ClipBox->GetBottom();

        if( x < ( x0 - r - 1 ) )
            return;

        if( y < ( y0 - r - 1 ) )
            return;

        if( x > ( r + xm + 1 ) )
            return;

        if( y > ( r + ym + 1 ) )
            return;
    }

    x1 = r;
    y1 = 0;
    RotatePoint( &x1, &y1, EndAngle );

    x2 = r;
    y2 = 0;
    RotatePoint( &x2, &y2, StAngle );

    GRSetBrush( DC, BgColor, FILLED );
    GRSetColorPen( DC, Color, width );
    DC->DrawArc( x + x1, y - y1, x + x2, y - y2, x, y );
}


void GRFilledArc( EDA_RECT* ClipBox, wxDC* DC, int x, int y,
                  double StAngle, double EndAngle, int r, 
                  EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    GRFilledArc( ClipBox, DC, x, y, StAngle, EndAngle, r, 0, Color, BgColor );
}


/*
 * Draw an arc in drawing space.
 */
void GRArc( EDA_RECT* ClipBox, wxDC* DC, int xc, int yc, double StAngle,
            double EndAngle, int r, EDA_COLOR_T Color )
{
    int x1, y1, x2, y2;

    /* Clip arcs off screen */
    if( ClipBox )
    {
        int radius = r + 1;
        int x0, y0, xm, ym, x, y;
        x0 = ClipBox->GetX();
        y0 = ClipBox->GetY();
        xm = ClipBox->GetRight();
        ym = ClipBox->GetBottom();
        x = xc;
        y = yc;

        if( x < ( x0 - radius ) )
            return;
        if( y < ( y0 - radius ) )
            return;
        if( x > ( xm + radius ) )
            return;
        if( y > ( ym + radius ) )
            return;
    }

    x1 = r;
    y1 = 0;
    RotatePoint( &x1, &y1, EndAngle );

    x2 = r;
    y2 = 0;
    RotatePoint( &x2, &y2, StAngle );

    GRSetColorPen( DC, Color );
    GRSetBrush( DC, Color, false );
    DC->DrawArc( xc + x1, yc - y1, xc + x2, yc - y2, xc, yc );
}


/*
 * Draw an arc with width = width in drawing space.
 */
void GRArc( EDA_RECT* ClipBox,
            wxDC*     DC,
            int       x,
            int       y,
            double    StAngle,
            double    EndAngle,
            int       r,
            int       width,
            EDA_COLOR_T       Color )
{
    int x1, y1, x2, y2;

    /* Clip arcs off screen. */
    if( ClipBox )
    {
        int x0, y0, xm, ym;
        x0 = ClipBox->GetX();
        y0 = ClipBox->GetY();
        xm = ClipBox->GetRight();
        ym = ClipBox->GetBottom();

        if( x < ( x0 - r - width ) )
            return;

        if( y < ( y0 - r - width ) )
            return;

        if( x > ( r + xm + width ) )
            return;

        if( y > ( r + ym + width ) )
            return;
    }

    x1 = r;
    y1 = 0;
    RotatePoint( &x1, &y1, EndAngle );

    x2 = r;
    y2 = 0;
    RotatePoint( &x2, &y2, StAngle );

    GRSetColorPen( DC, Color, width );
    GRSetBrush( DC, Color );
    DC->DrawArc( x + x1, y - y1, x + x2, y - y2, x, y );
}


/*
 * Draw a rectangle in drawing space.
 */
void GRRect( EDA_RECT* aClipBox, wxDC* aDC, int x1, int y1, int x2, int y2, EDA_COLOR_T aColor )
{
    GRSRect( aClipBox, aDC, x1, y1, x2, y2, 0, aColor );
}


void GRRectPs( EDA_RECT* aClipBox, wxDC* aDC, const EDA_RECT& aRect, EDA_COLOR_T aColor, wxPenStyle aStyle )
{
    int x1 = aRect.GetX();
    int y1 = aRect.GetY();
    int x2 = aRect.GetRight();
    int y2 = aRect.GetBottom();

    GRSRect( aClipBox, aDC, x1, y1, x2, y2, 0, aColor, aStyle );
}


/*
 * Draw a rectangle (thick lines) in drawing space.
 */
void GRRect( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2, int width, EDA_COLOR_T Color )
{
    GRSRect( ClipBox, DC, x1, y1, x2, y2, width, Color );
}


void GRRect( EDA_RECT* aClipBox, wxDC* aDC, const EDA_RECT& aRect, int aWidth, EDA_COLOR_T aColor )
{
    int x1 = aRect.GetX();
    int y1 = aRect.GetY();
    int x2 = aRect.GetRight();
    int y2 = aRect.GetBottom();

    GRSRect( aClipBox, aDC, x1, y1, x2, y2, aWidth, aColor );
}


/*
 * Draw a rectangle (filled with AreaColor) in drawing space.
 */
void GRFilledRect( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
                   EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    GRSFilledRect( ClipBox, DC, x1, y1, x2, y2, 0, Color, BgColor );
}


/*
 * Draw a rectangle (filled with AreaColor) in drawing space.
 */
void GRFilledRect( EDA_RECT* ClipBox, wxDC* DC, int x1, int y1, int x2, int y2,
                   int width, EDA_COLOR_T Color, EDA_COLOR_T BgColor )
{
    GRSFilledRect( ClipBox, DC, x1, y1, x2, y2, width, Color, BgColor );
}


/*
 * Draw a rectangle in screen space.
 */

void GRSRect( EDA_RECT* aClipBox, wxDC* aDC, int x1, int y1, int x2, int y2,
              int aWidth, EDA_COLOR_T aColor, wxPenStyle aStyle )
{

    wxPoint points[5];
    points[0] = wxPoint(x1, y1);
    points[1] = wxPoint(x1, y2);
    points[2] = wxPoint(x2, y2);
    points[3] = wxPoint(x2, y1);
    points[4] = points[0];
    GRSetColorPen( aDC, aColor, aWidth, aStyle );
    GRSetBrush( aDC, BLACK );
    if( aClipBox )
    {
        EDA_RECT clipbox(*aClipBox);
        clipbox.Inflate(aWidth);
        ClipAndDrawFilledPoly(&clipbox, aDC, points, 5); // polygon approach is more accurate
    }
    else
        ClipAndDrawFilledPoly(aClipBox, aDC, points, 5);
}


void GRSFilledRect( EDA_RECT* aClipBox, wxDC* aDC, int x1, int y1, int x2, int y2,
                    int aWidth, EDA_COLOR_T aColor, EDA_COLOR_T aBgColor )
{

    wxPoint points[5];
    points[0] = wxPoint(x1, y1);
    points[1] = wxPoint(x1, y2);
    points[2] = wxPoint(x2, y2);
    points[3] = wxPoint(x2, y1);
    points[4] = points[0];
    GRSetBrush( aDC, aBgColor, FILLED );
    GRSetColorPen( aDC, aBgColor, aWidth );
    if( aClipBox && (aWidth > 0) )
    {
        EDA_RECT clipbox(*aClipBox);
        clipbox.Inflate(aWidth);
        ClipAndDrawFilledPoly(&clipbox, aDC, points, 5); // polygon approach is more accurate
    }
    else
        ClipAndDrawFilledPoly(aClipBox, aDC, points, 5);
}


#ifdef USE_CLIP_FILLED_POLYGONS

/**
 * Function ClipAndDrawFilledPoly
 *  Used to clip a polygon and draw it as Filled Polygon
 *  uses the Sutherland and Hodgman algo to clip the given poly against a
 *  rectangle.  This rectangle is the drawing area this is useful under
 *  Linux (2009) because filled polygons are incorrectly drawn if they have
 *  too large coordinates (seems due to integer overflows in calculations)
 *  Could be removed in some years, if become unnecessary.
 */

/* Note: aClipBox == NULL is legal, so if aClipBox == NULL,
 * the polygon is drawn, but not clipped
 */
#include <SutherlandHodgmanClipPoly.h>

void ClipAndDrawFilledPoly( EDA_RECT* aClipBox, wxDC* aDC, wxPoint aPoints[], int n )
{
    if( aClipBox == NULL )
    {
        aDC->DrawPolygon( n, aPoints );
        return;
    }

    // A clip box exists: clip and draw the polygon.
    static vector<wxPoint> clippedPolygon;
    static pointVector     inputPolygon, outputPolygon;

    inputPolygon.clear();
    outputPolygon.clear();
    clippedPolygon.clear();

    for( int ii = 0; ii < n; ii++ )
        inputPolygon.push_back( PointF( (REAL) aPoints[ii].x, (REAL) aPoints[ii].y ) );

    RectF window( (REAL) aClipBox->GetX(), (REAL) aClipBox->GetY(),
                  (REAL) aClipBox->GetWidth(), (REAL) aClipBox->GetHeight() );

    SutherlandHodgman sh( window );
    sh.Clip( inputPolygon, outputPolygon );

    for( cpointIterator cit = outputPolygon.begin(); cit != outputPolygon.end(); ++cit )
    {
        clippedPolygon.push_back( wxPoint( KiROUND( cit->X ), KiROUND( cit->Y ) ) );
    }

    if( clippedPolygon.size() )
        aDC->DrawPolygon( clippedPolygon.size(), &clippedPolygon[0] );
}


#endif


void GRBezier( EDA_RECT* ClipBox,
               wxDC*     DC,
               int       x1,
               int       y1,
               int       x2,
               int       y2,
               int       x3,
               int       y3,
               int       width,
               EDA_COLOR_T       Color )
{
    std::vector<wxPoint> Points = Bezier2Poly( x1, y1, x2, y2, x3, y3 );
    GRPoly( ClipBox, DC, Points.size(), &Points[0], false, width, Color, Color );
}


void GRBezier( EDA_RECT* ClipBox,
               wxDC*     DC,
               int       x1,
               int       y1,
               int       x2,
               int       y2,
               int       x3,
               int       y3,
               int       x4,
               int       y4,
               int       width,
               EDA_COLOR_T       Color )
{
    std::vector<wxPoint> Points = Bezier2Poly( x1, y1, x2, y2, x3, y3, x4, y4 );
    GRPoly( ClipBox, DC, Points.size(), &Points[0], false, width, Color, Color );
}


EDA_COLOR_T ColorMix( EDA_COLOR_T aColor1, EDA_COLOR_T aColor2 )
{
    /* Memoization storage. This could be potentially called for each
     * color merge so a cache is useful (there are few colours anyway) */
    static EDA_COLOR_T mix_cache[NBCOLORS][NBCOLORS];

    // TODO how is alpha used? it's a mac only thing, I have no idea
    aColor1 = ColorGetBase( aColor1 );
    aColor2 = ColorGetBase( aColor2 );

    // First easy thing: a black gives always the other colour
    if( aColor1 == BLACK )
        return aColor2;
    if( aColor2 == BLACK)
        return aColor1;

    /* Now we are sure that black can't occur, so the rule is:
     * BLACK means not computed yet. If we're lucky we already have
     * an answer */
    EDA_COLOR_T candidate = mix_cache[aColor1][aColor2];
    if( candidate != BLACK )
        return candidate;

    // Blend the two colors (i.e. OR the RGB values)
    const StructColors &c1 = g_ColorRefs[aColor1];
    const StructColors &c2 = g_ColorRefs[aColor2];

    // Ask the palette for the nearest color to the mix
    wxColour mixed( c1.m_Red | c2.m_Red,
                    c1.m_Green | c2.m_Green,
                    c1.m_Blue | c2.m_Blue );
    candidate = ColorFindNearest( mixed );

    /* Here, BLACK is *not* a good answer, since it would recompute the next time.
     * Even theorically its not possible (with the current rules), but
     * maybe the metric will change in the future */
    if( candidate == BLACK)
        candidate = DARKDARKGRAY;

    // Store the result in the cache. The operation is commutative, too
    mix_cache[aColor1][aColor2] = candidate;
    mix_cache[aColor2][aColor1] = candidate;
    return candidate;
}


EDA_COLOR_T ColorByName( const wxChar *aName )
{
    // look for a match in the palette itself
    for( EDA_COLOR_T trying = BLACK; trying < NBCOLORS; trying = NextColor(trying) )
    {
        if( 0 == wxStricmp( aName, g_ColorRefs[trying].m_Name ) )
            return trying;
    }

    // Not found, no idea...
    return UNSPECIFIED_COLOR;
}

bool ColorIsLight( EDA_COLOR_T aColor )
{
    const StructColors &c = g_ColorRefs[ColorGetBase( aColor )];
    int r = c.m_Red;
    int g = c.m_Green;
    int b = c.m_Blue;
    return ((r * r) + (g * g) + (b * b)) > (128 * 128 * 3);
}

EDA_COLOR_T ColorFindNearest( const wxColour &aColor )
{
    EDA_COLOR_T candidate = BLACK;

    // These are ints because we will subtract them later
    int r = aColor.Red();
    int g = aColor.Green();
    int b = aColor.Blue();

    /* Find the 'nearest' color in the palette. This is fun. There is
       a gazilion of metrics for the color space and no one of the
       useful one is in the RGB color space. Who cares, this is a CAD,
       not a photosomething...

       I hereby declare that the distance is the sum of the square of the
       component difference. Think about the RGB color cube. Now get the
       euclidean distance, but without the square root... for ordering
       purposes it's the same, obviously. Also each component can't be
       less of the target one, since I found this currently work better...
       */
    int nearest_distance = 255 * 255 * 3 + 1; // Can't beat this

    for( EDA_COLOR_T trying = BLACK; trying < NBCOLORS; trying = NextColor(trying) )
    {
        const StructColors &c = g_ColorRefs[trying];
        int distance = (r - c.m_Red) * (r - c.m_Red) +
            (g - c.m_Green) * (g - c.m_Green) +
            (b - c.m_Blue) * (b - c.m_Blue);
        if( distance < nearest_distance && c.m_Red >= r &&
            c.m_Green >= g && c.m_Blue >= b )
        {
            nearest_distance = distance;
            candidate = trying;
        }
    }

    return candidate;
}

void GRDrawAnchor( EDA_RECT *aClipBox, wxDC *aDC, int x, int y, 
                   int aSize, EDA_COLOR_T aColor )
{
        int anchor_size = aDC->DeviceToLogicalXRel( aSize );

        GRLine( aClipBox, aDC,
                x - anchor_size, y,
                x + anchor_size, y, 0, aColor );
        GRLine( aClipBox, aDC,
                x, y - anchor_size,
                x, y + anchor_size, 0, aColor );
}