ColorVertex Shader

This topic shows the steps necessary to initialize and use a simple vertex shader that uses a position and a diffuse color.

The first step is to declare the structures that hold the position and color as shown in the code example below.

struct XYZBuffer
{
    FLOAT x, y, z;
};

struct ColBuffer
{
    D3DCOLOR color;
};

The next step is to create a vertex shader declaration as shown in the code below.

D3DVERTEXELEMENT9 decl[] = 
{
    { 0, 0, D3DDECLTYPE_FLOAT3,   D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_POSITION, 0 },
    { 1, 0, D3DDECLTYPE_D3DCOLOR, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_COLOR,    0 },
    D3DDECL_END()
};

Now create the vertex declaration object:

 
LPDIRECT3DVERTEXDECLARATION9 m_pVertexDeclaration;
g_d3dDevice->CreateVertexDeclaration( decl, &m_pVertexDeclaration );

The next step is to call the IDirect3DDevice9::CreateVertexShader method to create the vertex shader. But first, the shader must be assembled.

 
TCHAR               strVertexShaderPath[512];
LPD3DXBUFFER        pCode;
LPDIRECT3DVERTEXSHADER9	m_pVertexShader;

hr = DXUtil_FindMediaFileCb( strVertexShaderPath, 
                      sizeof(strVertexShaderPath), _T("ShaderFile.vsh");

hr = D3DXAssembleShaderFromFile( strVertexShaderPath, NULL, NULL, 
                      dwFlags, &pCode, NULL );

g_d3dDevice->CreateVertexShader( (DWORD*)pCode->GetBufferPointer(),
                      &m_pVertexShader );

The code example below shows how to set the vertex shader, set the stream source, and then render the triangle list.

g_pd3dDevice->SetVertexDeclaration( m_pVertexDeclaration );
g_d3dDevice->SetVertexShader( m_pVertexShader );
g_d3dDevice->SetStreamSource( 0, xyzbuf, sizeof(XYZBuffer));
g_d3dDevice->SetStreamSource( 1, colbuf, sizeof(ColBuffer));
g_d3dDevice->SetIndices( pIB, 0 );
g_d3dDevice->DrawIndexedPrimitive( D3DPT_TRIANGLELIST, 
                                   0, max - min + 1, 0, count / 3 );