벡터의 내적

m_fAngle = acosf(vDir.x * vLook.x + vDir.y * vLook.y); if(vMousePos.y > vPos.y) m_fAngle = 2 * D3DX_PI - m_fAngle; m_vPoint.x = 100.f * cosf(m_fAngle) + vPos.x; m_vPoint.y = -100.f * sinf(m_fAngle)+ vPos.y; m_vPoint.z = 0.f; vPos += vDir * m_fSpeed;