一个函数里 有一个纹理它是流动的 有方向性的 我想根据传入一个角度值变量改变流向 应该怎么做?

函数如下：
HRESULT WaveMesh::UpdateMesh(LPD3DXMESH m_pMesh)
{

if(!DrawStatus) return S_OK;
if(!WaveStatus) return S_OK;

//
HRESULT hr = S_OK;

//正弦波海洋模型相关参数
static float kexi0 = 0.06486f*WaveHeight;//0.4609f; 浪高1m
static float ws = 2.76f;//0.76624f;

static float oumiga[10] = { 0.559f, 0.861f, 0.936f, 1.008f, 1.083f,
1.167f, 1.272f, 1.412f, 1.635f, 2.193f };

static float fai[10] = { 1.651f, 2.942f, 4.818f, 6.012f, 1.930f,
6.017f, 1.133f, 5.682f, 4.791f, 2.319f };

static float k[10];
for(int i=0; i<10; i++)
{
k[i] = oumiga[i]*fai[1]*oumiga[i]*fai[1]/9.8f;
}
static float kk[10];
fr+=freq;
for(int i=0; i<10; i++)
{
kk[i] = oumiga[i]*ws*fr + fai[i];
}

//修改每个顶点的高度,得到海浪效果
static int iVertexCount = m_pMesh->GetNumVertices();//得到顶点总数
static float x, y,z;
static int s_count=0;
++s_count;
CUSTOMVERTEX* pVertices = NULL;//CUSTOMVERTEX结构体
V_RETURN( m_pMesh->LockVertexBuffer(0, (LPVOID*)&pVertices) );
static float sinpi=0.70710678118f;
static float cospi=0.70710678118f;
float spx=speedX*0.02/MaxLength;
float spy=speedY*0.02/MaxLength;
if(s_count==1)
{
float* numY=NULL;
numY = new float[iVertexCount];
for(int i=0;i<iVertexCount;i++)
{
numY[i]=pVertices[i].p.y;
}
initNumy=numY;
}
for(int i=0; i<iVertexCount; i++)
{
x = pVertices[i].p.x;
z = pVertices[i].p.z;
for(int j=0; j<10; j++)
{
pVertices[i].p.y +=cos(10+ k[j]*(x*sinpi + z*cospi) + kk[j]);
}
pVertices[i].p.y *= kexi0;
pVertices[i].p.y += initNumy[i];
x=pVertices[i].vTex.x+spx;
z=pVertices[i].vTex.y+spy;
pVertices[i].vTex= D3DXVECTOR2(x,z);
// pVertices[i].vTex2= D3DXVECTOR2(x,z);
}

m_pMesh->UnlockVertexBuffer();

//计算法线
// D3DXComputeNormals( m_pMesh, NULL );

return hr;
}