D3DXVec2CCW Function

Returns the z-component by taking the cross product of two 2-D vectors.

Syntax

FLOAT D3DXVec2CCW(      

    CONST D3DXVECTOR2 *pV1,
    CONST D3DXVECTOR2 *pV2
);

Parameters

pV1

[in] Pointer to a source D3DXVECTOR2 structure.

pV2

[in] Pointer to a source D3DXVECTOR2 structure.

Return Value

The z-component.

Remarks

This function determines the z-component by determining the cross-product based on the following formula: ((x1,y1,0) cross (x2,y2,0)). Or as shown in the following example.

pV1->x * pV2->y - pV1->y * pV2->x

If the value of the z-component is positive, the vector V2 is counterclockwise from the vector V1. This information is useful for back-face culling.

Function Information

Header	d3dx9math.h
Import library	d3dx9.lib
Minimum operating systems	Windows 98

See Also

D3DXVec2Dot