I was following along with the 2D in 3D tutorial at this site. A problem occurred when I realized that it was using some DX8 functions that no longer exist in DX9. So I switched them to their DX9 equivilants, however some of the parameters are completely different, and I''m not sure what to use for them. If I run the below function in my program, it crashes:

LPDIRECT3DVERTEXSHADER9 g_pVertexShader = NULL;
//Actually put in my InitD3D() function
g_pD3DDevice->GetVertexShader(&g_pVertexShader);

void InitBlit()
{
	// Turn off culling, so we see the front and back of primitives
	g_pD3DDevice->SetRenderState(D3DRS_CULLMODE, 
								D3DCULL_NONE);

	// Enable alpha blended transparency.
	g_pD3DDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);
	g_pD3DDevice->SetRenderState(
		D3DRS_SRCBLEND,  D3DBLEND_SRCALPHA);
	g_pD3DDevice->SetRenderState(
		D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);

	g_pD3DDevice->SetVertexShader(g_pVertexShader);

}
 

In this case, the difference was the SetVertexShader parameter. In DX9 it''s listed as, ''IDirect3DVertexShader9* pShader'', whereas in DX8 it''s listed as,''DWORD Handle''.

I tried that, and it still didn''t work.