SetVertexDeclaration()和SetFVF()
IDirect3DDevice9::SetVertexDeclaration
Sets a Vertex Declaration (Direct3D 9).
HRESULT SetVertexDeclaration( IDirect3DVertexDeclaration9 * pDecl );
Parameters
- pDecl
- [in] Pointer to an IDirect3DVertexDeclaration9 object, which contains the vertex declaration.
Return Values
If the method succeeds, the return value is D3D_OK. The return value can be D3DERR_INVALIDCALL.
Remarks
A vertex declaration is an IDirect3DVertexDeclaration9 object that defines the data members of a vertex (i.e. texture coordinates, colors, normals, etc.). This data can be useful for implementing vertex shaders and pixel shaders.
Requirements
Header: Declared in D3D9.h.
See Also
IDirect3DDevice9::GetVertexDeclaration
IDirect3DDevice9::SetFVF
Sets the current vertex stream declaration.
HRESULT SetFVF( DWORD FVF );
Parameters
- FVF
- [in] DWORD containing the fixed function vertex type. For more information, see D3DFVF.
Return Values
If the method succeeds, the return value is D3D_OK. If the method fails, the return value can be: D3DERR_INVALIDCALL.
Remarks
Here are the steps necessary to initialize and use vertices that have a position, diffuse and specular color, and texture coordinates:
- Define the custom vertex type and FVF code.
struct LVertex { FLOAT x, y, z; D3DCOLOR specular, diffuse; FLOAT tu, tv; }; const DWORD VertexFVF = (D3DFVF_XYZ | D3DFVF_DIFFUSE | D3DFVF_SPECULAR | D3DFVF_TEX1 );
- Create a vertex buffer with enough room for four vertices using IDirect3DDevice9::CreateVertexBuffer.
g_d3dDevice->CreateVertexBuffer( 4*sizeof(LVertex), D3DUSAGE_WRITEONLY, VertexFVF, D3DPOOL_DEFAULT, &pBigSquareVB, NULL );
- Set the values for each vertex.
LVertex * v; pBigSquareVB->Lock( 0, 0, (BYTE**)&v, 0 ); v[0].x = 0.0f; v[0].y = 10.0; v[0].z = 10.0f; v[0].diffuse = 0xffff0000; v[0].specular = 0xff00ff00; v[0].tu = 0.0f; v[0].tv = 0.0f; v[1].x = 0.0f; v[1].y = 0.0f; v[1].z = 10.0f; v[1].diffuse = 0xff00ff00; v[1].specular = 0xff00ffff; v[1].tu = 0.0f; v[1].tv = 0.0f; v[2].x = 10.0f; v[2].y = 10.0f; v[2].z = 10.0f; v[2].diffuse = 0xffff00ff; v[2].specular = 0xff000000; v[2].tu = 0.0f; v[2].tv = 0.0f; v[3].x = 0.0f; v[3].y = 10.0f; v[3].z = 10.0f; v[3].diffuse = 0xffffff00; v[3].specular = 0xffff0000; v[3].tu = 0.0f; v[3].tv = 0.0f; pBigSquareVB->Unlock();
- The vertex buffer has been initialized and is ready to render. The following code example shows how to use the legacy FVF to draw a square.
g_d3dDevice->SetFVF(VertexFVF); g_d3dDevice->SetStreamSource(0, pBigSquareVB, 0, sizeof(LVertex)); g_d3dDevice->DrawPrimitive(D3DPT_TRIANGLESTRIP, 0 ,2);
Here are the steps necessary to initialize and use vertices that have a position, a normal, and texture coordinates:
- Define the custom vertex type and FVF code.
struct Vertex { FLOAT x, y, z; FLOAT nx, ny, nz; FLOAT tu, tv; }; const DWORD VertexFVF = ( D3DFVF_XYZ | D3DFVF_NORMAL | D3DFVF_TEX1 );
- Create a vertex buffer with enough room for four vertices using IDirect3DDevice9::CreateVertexBuffer (similar to the example above).
- Set the values for each vertex.
Vertex * v; pBigSquareVB->Lock(0, 0, (BYTE**)&v, 0); v[0].x = 0.0f; v[0].y = 10.0; v[0].z = 10.0f; v[0].nx = 0.0f; v[0].ny = 1.0f; v[0].nz = 0.0f; v[0].tu = 0.0f; v[0].tv = 0.0f; v[1].x = 0.0f; v[1].y = 0.0f; v[1].z = 10.0f; v[1].nx = 0.0f; v[1].ny = 1.0f; v[1].nz = 0.0f; v[1].tu = 0.0f; v[1].tv = 0.0f; v[2].x = 10.0f; v[2].y = 10.0f; v[2].z = 10.0f; v[2].nx = 0.0f; v[2].ny = 1.0f; v[2].nz = 0.0f; v[2].tu = 0.0f; v[2].tv = 0.0f; v[3].x = 0.0f; v[3].y = 10.0f; v[3].z = 10.0f; v[3].nx = 0.0f; v[3].ny = 1.0f; v[3].nz = 0.0f; v[3].tu = 0.0f; v[3].tv = 0.0f; pBigSquareVB->Unlock();
- Draw the object (similar to the example above).
Requirements
Header: Declared in D3D9.h.
See Also
无论是可编程管线还是固定管线 SetVertexDeclaration 都比 SetFVF 高效。
SetVertexDeclaration 比 SetFVF 灵活,使用可编程管线时,复杂情况下 SetFVF 是不够用的。
效果不一定一样。
比如,SetVertexDeclaration可以设定纹理坐标是2个浮点数或者3个浮点数或者4个浮点数,也可以设定法线是3个浮点数或者4个浮点数或者一个4字节整数,非常灵活,此外还有很多别的特性,都是FVF做不到的,所以两者不一定能直接转换。