Get D3D1211On12 example working using call to D3D11On12CreateDevice

Question

I'm trying to get the C++ D3D1211On12 example working using windows-rs, but I can't get the call to D3D11On12CreateDevice to return a valid ID3D11Device.

The code I'm using is:

fn create_d11_device(pdevice: &ID3D12Device) -> Result<Option<*mut Option<windows::Win32::Graphics::Direct3D11::ID3D11Device>>> {
    unsafe {
        let ppdevice:Option<*mut Option<ID3D11Device>> = None;
        let ppimmediatecontext: Option<*mut Option<ID3D11DeviceContext>> = None;

        D3D11On12CreateDevice(pdevice, D3D11_CREATE_DEVICE_BGRA_SUPPORT.0, None, None, 0, 
            ppdevice, ppimmediatecontext, None  )?;

        Ok(ppdevice)
    }
}

Has anybody managed to this this call working?

Answer 1

The correct way to write this function is like this:

fn create_d11_device(pdevice: &ID3D12Device) -> Result<Option<ID3D11Device>> {
    unsafe {
        let mut ppdevice: Option<ID3D11Device> = None;
        let mut ppimmediatecontext: Option<ID3D11DeviceContext> = None;

        D3D11On12CreateDevice(pdevice, D3D11_CREATE_DEVICE_BGRA_SUPPORT.0, None, None, 0, 
            Some(&mut ppdevice), Some(&mut ppimmediatecontext), None  )?;

        Ok(ppdevice)
    }
}