[This is preliminary documentation and is subject to change.]

The absolute value of the returned value is two times the area of the triangle ABC.

Namespace: org.critterai.geom
Assembly: cai-util (in cai-util.dll) Version: 0.5.0.0 (0.5.0.0)

Syntax

         
 C#  Visual Basic  Visual C++ 
public static float GetSignedAreaX2(
	float ax,
	float ay,
	float bx,
	float by,
	float cx,
	float cy
)
Public Shared Function GetSignedAreaX2 ( _
	ax As Single, _
	ay As Single, _
	bx As Single, _
	by As Single, _
	cx As Single, _
	cy As Single _
) As Single
public:
static float GetSignedAreaX2(
	float ax, 
	float ay, 
	float bx, 
	float by, 
	float cx, 
	float cy
)

Parameters

ax
Single
The x-value for vertex A of triangle ABC
ay
Single
The y-value for vertex A of triangle ABC
bx
Single
The x-value for vertex B of triangle ABC
by
Single
The y-value for vertex B of triangle ABC
cx
Single
The x-value for vertex C of triangle ABC
cy
Single
The y-value for vertex C of triangle ABC

Return Value

The absolute value of the returned value is two times the area of the triangle ABC.

Remarks

A positive return value indicates:

  • Counterclockwise wrapping of the vertices.
  • Vertex B lies to the right of line AC, looking from A toward C.

A negative value indicates:

  • Clockwise wrapping of the vertices.
  • Vertex B lies to the left of line AC, looking from A toward C.

A value of zero indicates that all points are collinear or represent the same point.

This is a low cost method.

See Also