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UnsafeNativeMethods.Matrix.LookAtLH(Matrix,Vector3,Vector3,Vector3) Method (Microsoft.DirectX)

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Builds a left-handed look-at matrix.

Note: For programming in Microsoft Visual Basic .NET or Microsoft JScript .NET, use the equivalent method in the Microsoft.DirectX structures.

Definition

Visual Basic Public Shared Function LookAtLH( _
    ByVal pOut As Matrix, _
    ByVal cameraPosition As Vector3, _
    ByVal cameraTarget As Vector3, _
    ByVal cameraUpVector As Vector3 _
) As Matrix
C# public static Matrix LookAtLH(
    Matrix pOut,
    Vector3 cameraPosition,
    Vector3 cameraTarget,
    Vector3 cameraUpVector
);
C++ public:
static Matrix LookAtLH(
    Matrix pOut,
    Vector3 cameraPosition,
    Vector3 cameraTarget,
    Vector3 cameraUpVector
);
JScript public static function LookAtLH(
    pOut : Matrix,
    cameraPosition : Vector3,
    cameraTarget : Vector3,
    cameraUpVector : Vector3
) : Matrix;

Parameters

pOut Microsoft.DirectX.Matrix
A Matrix structure that is a left-handed look-at matrix.
cameraPosition Microsoft.DirectX.Vector3
A Vector3 structure that defines the camera point. This value is used in translation.
cameraTarget Microsoft.DirectX.Vector3
A Vector3 structure that defines the camera look-at target.
cameraUpVector Microsoft.DirectX.Vector3
A Vector3 structure that defines the up direction of the current world, usually [0, 1, 0].

Return Value

Microsoft.DirectX.Matrix
A Matrix structure that is a left-handed look-at matrix.

Remarks

This method uses the following formula to compute the returned matrix.

zaxis = normal(cameraTarget - cameraPosition)
xaxis = normal(cross(cameraUpVector, zaxis))
yaxis = cross(zaxis, xaxis)

 xaxis.x           yaxis.x           zaxis.x          0
 xaxis.y           yaxis.y           zaxis.y          0
 xaxis.z           yaxis.z           zaxis.z          0
-dot(xaxis, cameraPosition)  -dot(yaxis, cameraPosition)  -dot(zaxis, cameraPosition)  1

The return value for this method is the same value returned in the pOut parameter. This allows you to use the LookAtLH method as a parameter for another method.

See Also