Region.IsVisible(INT, INT, const Graphics*) method
Applies to: desktop apps only
The Region::IsVisible method determines whether a point is inside this region.
Syntax
BOOL IsVisible(
[in] INT x,
[in] INT y,
[in] const Graphics *g
) const;
Parameters
x [in]
Type: INTInteger that specifies the x-coordinate of the point to test.
y [in]
Type: INTInteger that specifies the y-coordinate of the point to test.
g [in]
Type: const Graphics*Optional. Pointer to a Graphics object that contains the world and page transformations required to calculate the device coordinates of this region and the point. The default value is NULL.
Return value
Type:
Type: BOOL
If the point is inside this region, this method returns TRUE; otherwise, it returns FALSE.
Examples
The following example creates a region from a path and then tests to determine whether a point is inside the region.
VOID Example_IsVisibleXY(HDC hdc)
{
Graphics graphics(hdc);
Point points[] = {
Point(110, 20),
Point(120, 30),
Point(100, 60),
Point(120, 70),
Point(150, 60),
Point(140, 10)};
GraphicsPath path;
SolidBrush solidBrush(Color(255, 255, 0, 0));
path.AddClosedCurve(points, 6);
// Create a region from a path.
Region pathRegion(&path);
graphics.FillRegion(&solidBrush, &pathRegion);
// Check to see whether the point (125, 40) is in the region.
INT x = 125;
INT y = 40;
if(pathRegion.IsVisible(x, y, &graphics))
{
// The point is in the region.
}
// Fill a small circle centered at the point (125, 40).
SolidBrush brush(Color(255, 0, 0, 0));
graphics.FillEllipse(&brush, x - 4, y - 4, 8, 8);
}
Requirements
Minimum supported client |
Windows XP, Windows 2000 Professional |
Minimum supported server |
Windows 2000 Server |
Product |
GDI+ 1.0 |
Header |
Gdiplusheaders.h (include Gdiplus.h) |
Library |
Gdiplus.lib |
DLL |
Gdiplus.dll |
See also
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Build date: 3/6/2012