Setting the Stream Source (Direct3D 9)

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The IDirect3DDevice9::SetStreamSource method binds a vertex buffer to a device data stream, creating an association between the vertex data and one of several data stream ports that feed the primitive processing functions. The actual references to the stream data do not occur until a drawing method, such as IDirect3DDevice9::DrawPrimitive, is called.

A stream is defined as a uniform array of component data, where each component consists of one or more elements representing a single entity such as position, normal, color, and so on. The Stride parameter specifies the size of the component, in bytes.

The following code demonstrates setting the stream source and drawing its contents. The g_pVB variable is a LPDIRECT3DVERTEXBUFFER9 that contains vertex data.

if( SUCCEEDED( g_pd3dDevice->BeginScene() ) )
{
    // Setup the world, view, and projection matrices
    SetupMatrices();

    // Render the vertex buffer contents
    g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof(CUSTOMVERTEX) );
    g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
    g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLESTRIP, 0, 1 );

    // End the scene
    g_pd3dDevice->EndScene();
}

For more information about this code see the following tutorial: Tutorial 3: Using Matrices

Rendering Primitives