public double MapArea(
	double area
)

public double MapArea(
	double area
)

Public Function MapArea ( 
	area As Double
) As Double

Public Function MapArea ( 
	area As Double
) As Double

public:
double MapArea(
	double area
)

public:
double MapArea(
	double area
)

Return Value

MapArea computes the mapped area by first calculating the area of a unit square and then multiplying the given area by the result. The area formed by two vectors is the cross product of the vectors. MapArea takes the vectors (1, 0) and (0, 1), maps these to the new coordinates, and then calculates the cross product. Given the following 2x2 matrix vector (1, 0) maps to (a, c) and vector (0,1) maps to (b, d). You calculate the cross product as: The cross product is also equivalent to the determinant. You may want to call MapArea with an area of 1.0 to get a conversion constant, and then use this constant in calculations. This saves the overhead of invoking MapArea multiple times.