Graphics.IsVisible Method (Single, Single)
Indicates whether the point specified by a pair of coordinates is contained within the visible clip region of this Graphics.
Assembly: System.Drawing (in System.Drawing.dll)
Parameters
- x
-
Type:
System.Single
The x-coordinate of the point to test for visibility.
- y
-
Type:
System.Single
The y-coordinate of the point to test for visibility.
Return Value
Type: System.Booleantrue if the point defined by the x and y parameters is contained within the visible clip region of this Graphics; otherwise, false.
The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following actions:
Creates a rectangular clipping region and sets it as the clipping region for the graphics object 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 void IsVisibleFloat(PaintEventArgs e) { // Set clip region. Region clipRegion = new Region(new Rectangle(50, 50, 100, 100)); e.Graphics.SetClip(clipRegion, CombineMode.Replace); // Set up coordinates of points. float x1 = 100.0F; float y1 = 100.0F; float x2 = 200.0F; float y2 = 200.0F; // If point is visible, fill ellipse that represents it. if (e.Graphics.IsVisible(x1, y1)) { e.Graphics.FillEllipse(new SolidBrush(Color.Red), x1, y1, 10.0F, 10.0F); } if (e.Graphics.IsVisible(x2, y2)) { e.Graphics.FillEllipse(new SolidBrush(Color.Blue), x2, y2, 10.0F, 10.0F); } }
Available since 1.1