This is the engine function (simplified) that renders to a texture:

Code:

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	LPDIRECT3DTEXTURE9 pTarget;
	D3DXCreateTexture(d3dDev,
			width,height,
			1,D3DUSAGE_RENDERTARGET,format,
			D3DPOOL_DEFAULT,&pTarget));

	LPDIRECT3DSURFACE pRenderTarget;
	pTarget->GetSurfaceLevel(0,&pRenderTarget);
	d3dDev->SetRenderTarget(0,pRenderTarget));
	SAFE_RELEASE(pRenderTarget);

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