Graphics.IsVisible Method (PointF)
Assembly: System.Drawing (in System.Drawing.dll)
Creates a rectangular clipping region and sets it as the clipping region for the graphics of the form using Replace.
Creates two points, one inside the clipping region and one outside.
Tests each of the points for visibility and draws only the visible one.
The result is one small red circle, which is within the clip region.
Private Sub IsVisiblePointF(ByVal e As PaintEventArgs) ' Set clip region. Dim clipRegion As New [Region](New Rectangle(50, 50, 100, 100)) e.Graphics.SetClip(clipRegion, CombineMode.Replace) ' Set up coordinates of points. Dim x1 As Single = 100.0F Dim y1 As Single = 100.0F Dim x2 As Single = 200.0F Dim y2 As Single = 200.0F Dim point1 As New PointF(x1, y1) Dim point2 As New PointF(x2, y2) ' If point is visible, fill ellipse that represents it. If e.Graphics.IsVisible(point1) Then e.Graphics.FillEllipse(New SolidBrush(Color.Red), x1, y1, _ 10.0F, 10.0F) End If If e.Graphics.IsVisible(point2) Then e.Graphics.FillEllipse(New SolidBrush(Color.Blue), x2, y2, _ 10.0F, 10.0F) End If End Sub
Available since 1.1