Implementation of playing audio out of focus

[masagrator]

I have tried to implement it on my own, but it seems I don't get your source code good enough :P

Here is the video showing an example of how it works, after pausing game sysmodule stops detecting if game is in focus because I guess thread exits in my implementation. :D That's why video ends there.

https://streamable.com/bmnzki

How to get if application is out of focus:
First we need to initialize pdmqry. As it has only 3 sessions free and we don't need active session for functions we use, we can clone service and close original one.

    pdmqryInitialize();
    Service* pdmqrySrv = pdmqryGetServiceSession();
    Service pdmqryClone;
    serviceClone(pdmqrySrv, &pdmqryClone);
    serviceClose(pdmqrySrv);
    memcpy(pdmqrySrv, &pdmqryClone, sizeof(Service));

For exiting standard pdmqryExit() will work.

Then there is this whole ass function to use

Result isApplicationOutOfFocus(u64 TIDnow, bool* outOfFocus) {
    static s32 last_total_entries = 0;
    static bool isOutOfFocus = false;
    s32 total_entries = 0;
    s32 start_entry_index = 0;
    s32 end_entry_index = 0;
    Result rc = pdmqryGetAvailablePlayEventRange(&total_entries, &start_entry_index, &end_entry_index);
    if (R_FAILED(rc)) return rc;
    if (total_entries == last_total_entries) {
        *outOfFocus = isOutOfFocus;
        return 0;
    }
    last_total_entries = total_entries;

    #define EVENT_COUNT 16
    PdmPlayEvent events[EVENT_COUNT];
    s32 out = 0;
    s32 start_entry = end_entry_index - (EVENT_COUNT-1);
    if (start_entry < 0) start_entry = 0;
    rc = pdmqryQueryPlayEvent(start_entry, events, EVENT_COUNT, &out);
    if (R_FAILED(rc)) return rc;
    if (out == 0) return 1;

    int itr = -1;
    for (int i = out-1; i >= 0; i--) {
        PdmPlayEvent* event = &events[i];
        if (event->play_event_type != PdmPlayEventType_Applet)
            continue;
        if (event->event_data.applet.applet_id != AppletId_application)
            continue;
        union {
            uint32_t parts[2];
            uint64_t full;
        } TID;
        TID.parts[0] = event->event_data.applet.program_id[1];
        TID.parts[1] = event->event_data.applet.program_id[0];

        if (TID.full != TIDnow && TID.full != (TIDnow & ~0xFFF)) //Retail games report always base titleid even when using different program
            continue;
        else {
            itr = i;
            break;
        }
    }
    if (itr == -1) return 1;

    bool isOut = events[itr].event_data.applet.event_type == PdmAppletEventType_OutOfFocus || events[itr].event_data.applet.event_type == PdmAppletEventType_OutOfFocus4;
    *outOfFocus = isOut;
    isOutOfFocus = isOut;
    return 0;
}

It works well enough in my SaltyNX (i modified it to only detect retail games though), it's very fast and never had an issue with wrong detection.

I am sending this as I would really like for music to play even when game is paused.

[HookedBehemoth]

Do you query this all the time, on a timeout or is there an event?

[masagrator]

I am using this always when I am sure that application runs, either pmdmnt or like in SaltyNX with svcGetProcessList after finding correct processID.

[masagrator]

With pdmqryGetAvailablePlayEventRange I am checking if there are new playevents, only after confirming that value has changed I am pulling PlayEvents with pdmqryQueryPlayEvent. Otherwise I return last confirmed focus state.

[masagrator]

There are thousands playevents to pull because it can also pull historical data stored on nand, so I'm limiting function to return only latest 16.

[masagrator]

Looking at libnx, there was a function for getting a system event if new application playevent was added, but it was removed in 15.0.0

If you think about improving it, avoid using pdmqryQueryPlayStatisticsByApplicationId and pdmqryQueryPlayStatisticsByApplicationIdAndUserAccountId as they filter all available playevents before returning, every time, which results in spending on it few hundred milliseconds on units with huge amount of historical data (also choking Core 3). They were making my single threaded sysmodule unresponsive. :D

There is an alternative pdmqryQueryAppletEvent, it's slightly slower than pdmqryQueryPlayEvent but i know people who use it in their sysmodules and don't complain. It returns only PdmPlayEventType_Applet playevents

[masagrator]

If someone is interested, this fork implemented functionality mentioned in this issue report.

https://github.com/ppkantorski/sys-tune