Emgu CV Library Documentation
cvPointPolygonTest Method (contour, pt, measureDist)
NamespacesEmgu.CVCvInvokecvPointPolygonTest(IntPtr, PointF, Int32)

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Determines whether the point is inside contour, outside, or lies on an edge (or coinsides with a vertex). It returns positive, negative or zero value, correspondingly
Declaration Syntax
C#Visual BasicVisual C++
public static double cvPointPolygonTest(
	IntPtr contour,
	PointF pt,
	int measureDist
)
Public Shared Function cvPointPolygonTest ( _
	contour As IntPtr, _
	pt As PointF, _
	measureDist As Integer _
) As Double
public:
static double cvPointPolygonTest(
	IntPtr contour, 
	PointF pt, 
	int measureDist
)
Parameters
contour (IntPtr)
Input contour
pt (PointF)
The point tested against the contour
measureDist (Int32)
If != 0, the function estimates distance from the point to the nearest contour edge
Return Value
When measureDist = 0, the return value is >0 (inside), <0 (outside) and =0 (on edge), respectively. When measureDist != 0, it is a signed distance between the point and the nearest contour edge

Assembly: Emgu.CV (Module: Emgu.CV) Version: 1.5.0.0 (1.5.0.0)