D3DXMatrixPerspectiveFovRH function (D3dx9math.h)
Note
The D3DX utility library is deprecated. We recommend that you use DirectXMath instead.
Builds a right-handed perspective projection matrix based on a field of view.
Syntax
D3DXMATRIX* D3DXMatrixPerspectiveFovRH(
_Inout_ D3DXMATRIX *pOut,
_In_ FLOAT fovy,
_In_ FLOAT Aspect,
_In_ FLOAT zn,
_In_ FLOAT zf
);
Parameters
-
pOut [in, out]
-
Type: D3DXMATRIX*
Pointer to the D3DXMATRIX structure that is the result of the operation.
-
fovy [in]
-
Type: FLOAT
Field of view in the y direction, in radians.
-
Aspect [in]
-
Type: FLOAT
Aspect ratio, defined as view space width divided by height.
-
zn [in]
-
Type: FLOAT
Z-value of the near view-plane.
-
zf [in]
-
Type: FLOAT
Z-value of the far view-plane.
Return value
Type: D3DXMATRIX*
Pointer to a D3DXMATRIX structure that is a right-handed perspective projection matrix.
Remarks
The return value for this function is the same value returned in the pOut parameter. In this way, the D3DXMatrixPerspectiveFovRH function can be used as a parameter for another function.
To change the aspect ratio axis, use the calculation formula: fovy = 2 * math.atan(math.tan(fovy * 0.5) / aspect). Alternatively, add X and Y aspect ratio variables in the structure to scale the vertical view space: fovy = 2 * math.atan(math.tan(fovy * 0.5) / aspectY), aspect = aspectX * aspect Y.
This function computes the returned matrix as shown.
xScale 0 0 0
0 yScale 0 0
0 0 zf/(zn-zf) -1
0 0 zn*zf/(zn-zf) 0
where:
yScale = cot(fovY/2)
xScale = yScale / aspect ratio
Requirements
| Requirement | Value |
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| Header |
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| Library |
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See also