D3DXSHAdd

Adds two spherical harmonic (SH) vectors; in other words, pOut[i] = pA[i] + pB[i].

FLOAT * D3DXSHAdd(
  FLOAT * pOut,
  UINT Order,
  CONST FLOAT * pA,
  CONST FLOAT * pB
);

Parameters

pOut

[out] Pointer to SH output coefficients. The evaluation generates Order² coefficients. See Remarks.

Order

[in] Order of the SH evaluation. Must be in the range of D3DXSH_MINORDER to D3DXSH_MAXORDER, inclusive. The evaluation generates Order² coefficients. The degree of the evaluation is Order - 1.

pA

[in] Pointer to the first SH vector.

pB

[in] Pointer to the second SH vector.

Return Values

Pointer to SH output coefficients.

Remarks

Each coefficient of the basis function Y_lm is stored at memory location l² + m + l, where:

• l is the degree of the basis function.
• m is the basis function index for the given l value and ranges from -l to l, inclusive.

Requirements

Header: Declared in D3dx9math.h.

See Also

Precomputed Radiance Transfer