bool HMDState::ConfigureRendering(ovrEyeRenderDesc eyeRenderDescOut[2],
                                  const ovrFovPort eyeFovIn[2],
                                  const ovrRenderAPIConfig* apiConfig,
                                  unsigned distortionCaps)
{
    ThreadChecker::Scope checkScope(&RenderAPIThreadChecker, "ovrHmd_ConfigureRendering");

    // null -> shut down.
    if (!apiConfig)
    {
        if (pHSWDisplay)
        {
            pHSWDisplay->Shutdown();
            pHSWDisplay.Clear();
        }

        if (pRenderer)
            pRenderer.Clear();
        RenderingConfigured = false;
        return true;
    }

    if (pRenderer &&
        (apiConfig->Header.API != pRenderer->GetRenderAPI()))
    {
        // Shutdown old renderer.
        if (pHSWDisplay)
        {
            pHSWDisplay->Shutdown();
            pHSWDisplay.Clear();
        }

        if (pRenderer)
            pRenderer.Clear();
    }

	distortionCaps = distortionCaps & pHmdDesc->DistortionCaps;

    // Step 1: do basic setup configuration
    RenderState.EnabledHmdCaps = EnabledHmdCaps;     // This is a copy... Any cleaner way?
    RenderState.DistortionCaps = distortionCaps;
    RenderState.EyeRenderDesc[0] = RenderState.CalcRenderDesc(ovrEye_Left,  eyeFovIn[0]);
    RenderState.EyeRenderDesc[1] = RenderState.CalcRenderDesc(ovrEye_Right, eyeFovIn[1]);
    eyeRenderDescOut[0] = RenderState.EyeRenderDesc[0];
    eyeRenderDescOut[1] = RenderState.EyeRenderDesc[1];

    TimeManager.ResetFrameTiming(0,
                                 (EnabledHmdCaps & ovrHmdCap_DynamicPrediction) ? true : false,
                                 true);

    LastFrameTimeSeconds = 0.0f;

    // Set RenderingConfigured early to avoid ASSERTs in renderer initialization.
    RenderingConfigured = true;

    if (!pRenderer)
    {
        pRenderer = *DistortionRenderer::APICreateRegistry
                        [apiConfig->Header.API](pHmdDesc, TimeManager, RenderState);
    }

    if (!pRenderer ||
        !pRenderer->Initialize(apiConfig))
    {
        RenderingConfigured = false;
        return false;
    }

    // Setup the Health and Safety Warning display system.
    if(pHSWDisplay && (pHSWDisplay->GetRenderAPIType() != apiConfig->Header.API)) // If we need to reconstruct the HSWDisplay for a different graphics API type, delete the existing display.
    {
        pHSWDisplay->Shutdown();
        pHSWDisplay.Clear();
    }

    if(!pHSWDisplay) // Use * below because that for of operator= causes it to inherit the refcount the factory gave the object.
    {
        pHSWDisplay = *OVR::CAPI::HSWDisplay::Factory(apiConfig->Header.API, pHmdDesc, RenderState);
        pHSWDisplay->Enable(pProfile->GetBoolValue("HSW", true));
    }

    if (pHSWDisplay)
        pHSWDisplay->Initialize(apiConfig); // This is potentially re-initializing it with a new config.

    return true;
}