類CDXUTMeshFrame封裝了CDXUTMesh，與CDXUTMesh不同的是，類CDXUTMeshFrame可以包含框架層次結構，適用于更復雜的網格模型，框架層次正是骨骼動畫所必須的。
首先來看看它的定義：
//-----------------------------------------------------------------------------
// Name: class CDXUTMeshFrame
// Desc: Class for loading and rendering file-based meshes
//-----------------------------------------------------------------------------
class CDXUTMeshFrame
{
public:
WCHAR m_strName[512]; // 框架名稱
D3DXMATRIX m_mat; // 框架變換矩陣（相對于網格模型的原點）
CDXUTMesh* m_pMesh; // 指向CDXUTMesh對象
CDXUTMeshFrame* m_pNext; // 指向下一個框架對象
CDXUTMeshFrame* m_pChild; // 指向子框架對象
public:
// Matrix access
void SetMatrix( D3DXMATRIX* pmat ) { m_mat = *pmat; }
D3DXMATRIX* GetMatrix() { return &m_mat; }
CDXUTMesh* FindMesh( LPCWSTR strMeshName );
CDXUTMeshFrame* FindFrame( LPCWSTR strFrameName );
bool EnumMeshes( bool (*EnumMeshCB)(CDXUTMesh*, void*), void* pContext );
HRESULT Destroy();
HRESULT RestoreDeviceObjects(LPDIRECT3DDEVICE9 pd3dDevice);
HRESULT InvalidateDeviceObjects();
HRESULT Render( LPDIRECT3DDEVICE9 pd3dDevice,
bool bDrawOpaqueSubsets = true,
bool bDrawAlphaSubsets = true,
D3DXMATRIX* pmatWorldMatrix = NULL);
CDXUTMeshFrame( LPCWSTR strName = L"CDXUTMeshFile_Frame" );
virtual ~CDXUTMeshFrame();
};
構造函數和析構函數只是負責初始化數據和釋放分配的資源：
CDXUTMeshFrame::CDXUTMeshFrame( LPCWSTR strName )
{
StringCchCopy(m_strName, 512, strName);
D3DXMatrixIdentity(&m_mat);
m_pMesh = NULL;
m_pChild = NULL;
m_pNext = NULL;
}
CDXUTMeshFrame::~CDXUTMeshFrame()
{
SAFE_DELETE( m_pChild );
SAFE_DELETE( m_pNext );
}
FindMesh()和FindFrame()是兩個遞歸查找函數，根據輸入的網格名稱和框架名稱查找對應的網格和框架：
CDXUTMesh* CDXUTMeshFrame::FindMesh( LPCWSTR strMeshName )
{
CDXUTMesh* pMesh;
if( m_pMesh )
if( !lstrcmpi(m_pMesh->m_strName, strMeshName) )
return m_pMesh;
if( m_pChild )
if( NULL != ( pMesh = m_pChild->FindMesh(strMeshName) ) )
return pMesh;
if( m_pNext )
if( NULL != ( pMesh = m_pNext->FindMesh(strMeshName) ) )
return pMesh;
return NULL;
}
CDXUTMeshFrame* CDXUTMeshFrame::FindFrame( LPCWSTR strFrameName )
{
CDXUTMeshFrame* pFrame;
if( !lstrcmpi(m_strName, strFrameName) )
return this;
if( m_pChild )
if( NULL != ( pFrame = m_pChild->FindFrame(strFrameName) ) )
return pFrame;
if( m_pNext )
if( NULL != ( pFrame = m_pNext->FindFrame(strFrameName) ) )
return pFrame;
return NULL;
}
lstrcmpi()在比較兩個字符串時忽略大小寫：
The lstrcmpi function compares two character
strings. The comparison is not case sensitive.
To perform a comparison that is case sensitive, use
the lstrcmp function.
Syntax
int lstrcmpi(
LPCTSTR lpString1,
LPCTSTR lpString2
);
Parameters
- lpString1
- [in] Pointer to the first null-terminated
string to be compared.
- lpString2
- [in] Pointer to the second null-terminated
string to be compared.
Return Value
If the string pointed to by lpString1 is
less than the string pointed to by lpString2, the return value is
negative. If the string pointed to by lpString1 is greater than
the string pointed to by lpString2, the return value is positive.
If the strings are equal, the return value is zero.
Remarks
The lstrcmpi function compares two
strings by checking the first characters against each other, the second
characters against each other, and so on until it finds an inequality or
reaches the ends of the strings.
Note that the lpString1 and lpString2
parameters must be null terminated, otherwise the string comparison can
be incorrect.
The function returns the difference of the
values of the first unequal characters it encounters. For example,
lstrcmpi determines that "abcz" is greater than "abcdefg" and
returns the difference of z and d.
The language (user locale) selected by the user
at setup time, or through Control Panel, determines which string is
greater (or whether the strings are the same). If no language (user
locale) is selected, the system performs the comparison by using default
values.
For some locales, the lstrcmpi function
may be insufficient. If this occurs, use CompareString to ensure proper
comparison. For example, in Japan call with the
NORM_IGNORECASE, NORM_IGNOREKANATYPE,
and NORM_IGNOREWIDTH values to achieve the
most appropriate non-exact string comparison. The
NORM_IGNOREKANATYPE and NORM_IGNOREWIDTH
values are ignored in non-Asian locales, so you can set these values for
all locales and be guaranteed to have a culturally correct "insensitive"
sorting regardless of the locale. Note that specifying these values
slows performance, so use them only when necessary.
With a double-byte character set (DBCS) version
of the system, this function can compare two DBCS strings.
The lstrcmpi function uses a word sort,
rather than a string sort. A word sort treats hyphens and apostrophes
differently than it treats other symbols that are not alphanumeric, in
order to ensure that words such as "coop" and "co-op" stay together
within a sorted list. For a detailed discussion of word sorts and string
sorts, see the Remarks section for the CompareString function.
EnumMeshes()是一個遞歸枚舉函數，對所有框架的所有網格遞歸調用傳遞進來的函數：
bool CDXUTMeshFrame::EnumMeshes( bool (*EnumMeshCB)(CDXUTMesh*, void*), void* pContext )
{
if( m_pMesh )
EnumMeshCB( m_pMesh, pContext );
if( m_pChild )
m_pChild->EnumMeshes( EnumMeshCB, pContext );
if( m_pNext )
m_pNext->EnumMeshes( EnumMeshCB, pContext );
return TRUE;
}
Destroy()、RestoreDeviceObjects()、InvalidateDeviceObjects()分別當摧毀網格框架、設備恢復、設備丟失時調用，需要注意的是該類的析構函數并沒有釋放分配的資源，只是刪除了鏈表指針，必須顯式調用Destroy()來釋放資源：
HRESULT CDXUTMeshFrame::Destroy()
{
if( m_pMesh ) m_pMesh->Destroy();
if( m_pChild ) m_pChild->Destroy();
if( m_pNext ) m_pNext->Destroy();
SAFE_DELETE( m_pMesh );
SAFE_DELETE( m_pNext );
SAFE_DELETE( m_pChild );
return S_OK;
}
HRESULT CDXUTMeshFrame::RestoreDeviceObjects( LPDIRECT3DDEVICE9 pd3dDevice )
{
if( m_pMesh ) m_pMesh->RestoreDeviceObjects( pd3dDevice );
if( m_pChild ) m_pChild->RestoreDeviceObjects( pd3dDevice );
if( m_pNext ) m_pNext->RestoreDeviceObjects( pd3dDevice );
return S_OK;
}
HRESULT CDXUTMeshFrame::InvalidateDeviceObjects()
{
if( m_pMesh ) m_pMesh->InvalidateDeviceObjects();
if( m_pChild ) m_pChild->InvalidateDeviceObjects();
if( m_pNext ) m_pNext->InvalidateDeviceObjects();
return S_OK;
}
Render()負責網格框架的繪制，它只是調用CDXUTMesh::Render()來負責網格的繪制，由于框架的層次包含關系，所以該函數也是一個遞歸函數。需要注意的是該函數包含的最后一個參數，它允許用戶指定世界坐標變換矩陣，如果該參數為NULL，則從設備獲取已設置好的世界坐標矩陣，注意如果是虛擬設備，必須設置該矩陣，不能為NULL。
HRESULT CDXUTMeshFrame::Render( LPDIRECT3DDEVICE9 pd3dDevice,
bool bDrawOpaqueSubsets, bool bDrawAlphaSubsets,
D3DXMATRIX* pmatWorldMatrix )
{
// For pure devices, specify the world transform.
// If the world transform is not specified on pure devices, this function will fail.
D3DXMATRIX matSavedWorld, matWorld;
if (NULL == pmatWorldMatrix)
pd3dDevice->GetTransform(D3DTS_WORLD, &matSavedWorld);
else
matSavedWorld = *pmatWorldMatrix;
D3DXMatrixMultiply(&matWorld, &m_mat, &matSavedWorld);
pd3dDevice->SetTransform(D3DTS_WORLD, &matWorld);
if( m_pMesh )
m_pMesh->Render(pd3dDevice, bDrawOpaqueSubsets, bDrawAlphaSubsets);
if( m_pChild )
m_pChild->Render(pd3dDevice, bDrawOpaqueSubsets, bDrawAlphaSubsets, &matWorld);
pd3dDevice->SetTransform(D3DTS_WORLD, &matSavedWorld);
if( m_pNext )
m_pNext->Render( pd3dDevice, bDrawOpaqueSubsets, bDrawAlphaSubsets, &matSavedWorld );
return S_OK;
}
代碼中需要注意的一點是，調用Render()繪制兄弟框架時傳遞的世界坐標矩陣是matSavedWorld，而繪制子框架時傳遞的世界坐標矩陣是matWorld。