DirectX SDK

D3DXPlaneDot

The D3DXPlaneDot function computes the dot-product of a plane and a 4-D vector.

float D3DXPlaneDot(
  const D3DXPLANE* pP,
  const D3DXVECTOR4* pV
); 

Parameters

pP
A pointer to a source D3DXPLANE structure.
pV
A pointer to a D3DXVECTOR4 structure.

Return Values

The dot-product of the given plane and 4-D vector.

Remarks

Given a plane (a, b, c, d) and a 4-D vector (x, y, z, w) the return value of this function is a*x + b*y + c*z + d*w. The D3DXPlaneDot function is useful for determining the plane's relationship with a homogeneous coordinate. For example, this function could be used to determine if a particular coordinate is on a particular plane, or on which side of a particular plane a particular coordinate lies.

Requirements

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Windows CE: Unsupported.
  Version: Requires DirectX 7.0.
  Header: Declared in d3dxmath.h.
  Library: Use d3dx.lib.

See Also

D3DXPlaneDotCoord, D3DXPlaneDotNormal