Region::IsVisible(INT,INT,constGraphics*) method (gdiplusheaders.h)
The Region::IsVisible method determines whether a point is inside this region.
Syntax
BOOL IsVisible(
INT x,
INT y,
const Graphics *g
);
Parameters
x
Integer that specifies the x-coordinate of the point to test.
y
Integer that specifies the y-coordinate of the point to test.
g
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: Status
If the method succeeds, it returns Ok, which is an element of the Status enumeration.
If the method fails, it returns one of the other elements of the Status enumeration.
Remarks
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
Requirement | Value |
---|---|
Header | gdiplusheaders.h |