feat(agc): read the pad snapshot only while the panel is wanted

PadStatusDisplay::Poll asks the provider for a snapshot only when the
panel can be shown: in the events mode always, otherwise only while a
request keeps it visible. With ANYPS5_PAD_STATUS unset or 0 and no
request the provider is not called, so the host builds no snapshot and
reads no controller state for it. An unchanged snapshot is not observed
again, and a display that stopped being polled observes the next
snapshot afresh when a request makes it wanted again. The entry point
for the host's pad code is AgcDriverPadStatusPoll_nid_postfix.

core/libs/prx/libSceAgcDriver/Execution/include/PadStatusOverlay.hpp

@@ -41,6 +41,8 @@ public:
     bool Observe(Clock::time_point now, const PadStatusSnapshot& snapshot);
     void Request(Clock::time_point now);
     bool Visible(Clock::time_point now) const;
+    bool Wants(Clock::time_point now) const;
+    bool Poll(Clock::time_point now, const PadStatusProvider& provider);
     std::vector<std::string> Lines() const;
 
 private:
@@ -48,11 +50,13 @@ private:
     std::optional<PadStatusSnapshot> previous;
     std::array<bool, PadStatusSlots> seen{};
     std::optional<Clock::time_point> shownUntil;
+    std::optional<PadStatusSnapshot> polled;
 };
 
 }
 
 extern "C" void AgcDriverPadStatusObserve_nid_postfix(const AgcDriver::PadStatusSnapshot* snapshot);
+extern "C" void AgcDriverPadStatusPoll_nid_postfix(const AgcDriver::PadStatusProvider* provider);
 extern "C" void AgcDriverPadStatusShow_nid_postfix();
 
 #endif

core/libs/prx/libSceAgcDriver/Execution/src/PadStatusOverlay.cpp

@@ -5,6 +5,7 @@
 #include <mutex>
 #include <stdexcept>
 #include <string_view>
+#include <utility>
 
 namespace AgcDriver {
 namespace {
@@ -132,6 +133,21 @@ bool PadStatusDisplay::Visible(Clock::time_point now) const {
     return shownUntil.has_value() && now < *shownUntil;
 }
 
+bool PadStatusDisplay::Wants(Clock::time_point now) const {
+    return mode == PadStatusMode::Events || Visible(now);
+}
+
+bool PadStatusDisplay::Poll(Clock::time_point now, const PadStatusProvider& provider) {
+    if (!Wants(now)) {
+        polled.reset();
+        return false;
+    }
+    auto snapshot = provider.read();
+    if (!polled.has_value() || *polled != snapshot) Observe(now, snapshot);
+    polled = std::move(snapshot);
+    return true;
+}
+
 std::vector<std::string> PadStatusDisplay::Lines() const {
     std::vector<std::string> lines;
     for (std::size_t slot = 0; slot < PadStatusSlots; ++slot) {
@@ -166,6 +182,11 @@ extern "C" void AgcDriverPadStatusObserve_nid_postfix(const AgcDriver::PadStatus
     AgcDriver::display().Observe(AgcDriver::PadStatusDisplay::Clock::now(), *snapshot);
 }
 
+extern "C" void AgcDriverPadStatusPoll_nid_postfix(const AgcDriver::PadStatusProvider* provider) {
+    std::lock_guard lock(AgcDriver::displayMutex);
+    AgcDriver::display().Poll(AgcDriver::PadStatusDisplay::Clock::now(), *provider);
+}
+
 extern "C" void AgcDriverPadStatusShow_nid_postfix() {
     std::lock_guard lock(AgcDriver::displayMutex);
     AgcDriver::display().Request(AgcDriver::PadStatusDisplay::Clock::now());