Added GenerateRichPresence to AchievementManager

GenerateRichPresence calls rc_runtime_get_richpresence in rhceevos on the achievement runtime to get the current Rich Presence string, a description of the player's current in-game state based on its memory as fed into a custom-developed script downloaded via FetchGameData. This gets passed into PingRichPresence, but is separated into its own method so it can be used elsewhere locally.

Source/Core/Core/AchievementManager.cpp

@@ -409,6 +409,20 @@ void AchievementManager::ActivateDeactivateAchievement(AchievementId id, bool en
     rc_runtime_deactivate_achievement(&m_runtime, id);
 }
 
+RichPresence AchievementManager::GenerateRichPresence()
+{
+  RichPresence rp_buffer;
+  Core::RunAsCPUThread([&] {
+    rc_runtime_get_richpresence(
+        &m_runtime, rp_buffer.data(), RP_SIZE,
+        [](unsigned address, unsigned num_bytes, void* ud) {
+          return static_cast<AchievementManager*>(ud)->MemoryPeeker(address, num_bytes, ud);
+        },
+        this, nullptr);
+  });
+  return rp_buffer;
+}
+
 AchievementManager::ResponseType AchievementManager::AwardAchievement(AchievementId achievement_id)
 {
   std::string username = Config::Get(Config::RA_USERNAME);

Source/Core/Core/AchievementManager.h

@@ -72,6 +72,7 @@ private:
   ResponseType FetchUnlockData(bool hardcore);
 
   void ActivateDeactivateAchievement(AchievementId id, bool enabled, bool unofficial, bool encore);
+  RichPresence GenerateRichPresence();
 
   ResponseType AwardAchievement(AchievementId achievement_id);
   ResponseType SubmitLeaderboard(AchievementId leaderboard_id, int value);