The following example draws a pair of Bézier curves.
C++
VOID Example_DrawBeziers2(HDC hdc)
{
Graphics graphics(hdc);
// Define a Pen object and an array of PointF objects.
Pen greenPen(Color(255, 0, 255, 0), 3);
PointF startPoint(100.0f, 100.0f);
PointF ctrlPoint1(200.0f, 50.0f);
PointF ctrlPoint2(400.0f, 10.0f);
PointF endPoint1(500.0f, 100.0f);
PointF ctrlPoint3(600.0f, 200.0f);
PointF ctrlPoint4(700.0f, 400.0f);
PointF endPoint2(500.0f, 500.0f);
PointF curvePoints[7] = {
startPoint,
ctrlPoint1,
ctrlPoint2,
endPoint1,
ctrlPoint3,
ctrlPoint4,
endPoint2};
// Draw the Bezier curves.
graphics.DrawBeziers(&greenPen, curvePoints, 7);
// Draw the control and end points.
SolidBrush redBrush(Color(255, 255, 0, 0));
graphics.FillEllipse(&redBrush, Rect(100 - 5, 100 - 5, 10, 10));
graphics.FillEllipse(&redBrush, Rect(500 - 5, 100 - 5, 10, 10));
graphics.FillEllipse(&redBrush, Rect(500 - 5, 500 - 5, 10, 10));
SolidBrush blueBrush(Color(255, 0, 0, 255));
graphics.FillEllipse(&blueBrush, Rect(200 - 5, 50 - 5, 10, 10));
graphics.FillEllipse(&blueBrush, Rect(400 - 5, 10 - 5, 10, 10));
graphics.FillEllipse(&blueBrush, Rect(600 - 5, 200 - 5, 10, 10));
graphics.FillEllipse(&blueBrush, Rect(700 - 5, 400 - 5, 10, 10));
}
SUB GDIP_DrawBeziers (BYVAL hdc AS DWORD)
LOCAL hStatus AS LONG
LOCAL pGraphics AS DWORD
LOCAL pGreenPen AS DWORD
LOCAL pRedBrush AS DWORD
LOCAL pBlueBrush AS DWORD
LOCAL startPoint AS POINTF
LOCAL ctrlPoint1 AS POINTF
LOCAL ctrlPoint2 AS POINTF
LOCAL endPoint1 AS POINTF
LOCAL ctrlPoint3 AS POINTF
LOCAL ctrlPoint4 AS POINTF
LOCAL endPoint2 AS POINTF
DIM curvePoints(6) AS POINTF
hStatus = GdipCreateFromHDC(hdc, pGraphics)
' // Create a green Pen
hStatus = GdipCreatePen1(GDIP_ARGB(255, 0, 255, 0), 1.0!, %UnitWorld, pGreenPen)
startPoint.x = 100.0 : startPoint.y = 100.0
ctrlPoint1.x = 200.0 : ctrlPoint1.y = 50.0
ctrlPoint2.x = 400.0 : ctrlPoint2.y = 10.0
endPoint1.x = 500.0 : endPoint1.y = 100.0
ctrlPoint3.x = 600.0 : ctrlPoint3.y = 200.0
ctrlPoint4.x = 700.0 : ctrlPoint4.y = 400.0
endPoint1.x = 500.0 : endPoint1.y = 500.0
curvePoints(0) = startPoint
curvePoints(1) = ctrlPoint1
curvePoints(2) = ctrlPoint2
curvePoints(3) = endPoint1
curvePoints(4) = ctrlPoint3
curvePoints(5) = ctrlPoint4
curvePoints(6) = endPoint2
' // Draw the Bézier curves
hStatus = GdipDrawBeziers(pGraphics, pGreenPen, curvePoints(0), 7)
' // Create the brushes
hStatus = GdipCreateSolidFill(GDIP_ARGB(255, 255, 0, 0), pRedBrush)
hStatus = GdipCreateSolidFill(GDIP_ARGB(255, 0, 0, 255), pBlueBrush)
' //Draw the end points and control points.
hStatus = GdipFillEllipse(pGraphics, pRedBrush, 100 - 5, 100 - 5, 10, 10)
hStatus = GdipFillEllipse(pGraphics, pRedBrush, 500 - 5, 100 - 5, 10, 10)
hStatus = GdipFillEllipse(pGraphics, pRedBrush, 500 - 5, 500 - 5, 10, 10)
hStatus = GdipFillEllipse(pGraphics, pBlueBrush, 200 - 5, 50 - 5, 10, 10)
hStatus = GdipFillEllipse(pGraphics, pBlueBrush, 400 - 5, 10 - 5, 10, 10)
hStatus = GdipFillEllipse(pGraphics, pBlueBrush, 600 - 5, 200 - 5, 10, 10)
hStatus = GdipFillEllipse(pGraphics, pBlueBrush, 700 - 5, 400 - 5, 10, 10)
' // Cleanup
IF pBlueBrush THEN GdipDeleteBrush(pBlueBrush)
IF pRedBrush THEN GdipDeleteBrush(pRedBrush)
IF pGreenPen THEN GdipDeletePen(pGreenPen)
IF pGraphics THEN GdipDeleteGraphics(pGraphics)
END SUB
(http://www.jose.it-berater.org/captures/GdipDrawBeziers.png)