From b2387e06bc3562d15d2d41fc608d0bb3d088ed41 Mon Sep 17 00:00:00 2001
From: Themaister <maister@archlinux.us>
Date: Fri, 1 Jun 2012 16:50:38 +0200
Subject: [PATCH] Add RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL.

---
 dynamic.c  |  4 ++++
 general.h  |  1 +
 libretro.h | 20 ++++++++++++++++++++
 3 files changed, 25 insertions(+)

diff --git a/dynamic.c b/dynamic.c
index 2bf7d65f46..c0d2a8d542 100644
--- a/dynamic.c
+++ b/dynamic.c
@@ -320,6 +320,10 @@ static bool environment_cb(unsigned cmd, void *data)
          g_extern.system.shutdown = true;
          break;
 
+      case RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL:
+         g_extern.system.performance_level = *(const unsigned*)data;
+         break;
+
       default:
          RARCH_LOG("Environ UNSUPPORTED (#%u).\n", cmd);
          return false;
diff --git a/general.h b/general.h
index 40c75fe97a..17680d65af 100644
--- a/general.h
+++ b/general.h
@@ -329,6 +329,7 @@ struct global
 
       unsigned rotation;
       bool shutdown;
+      unsigned performance_level;
    } system;
 
    struct
diff --git a/libretro.h b/libretro.h
index 1ce9cbd382..d9309214c9 100755
--- a/libretro.h
+++ b/libretro.h
@@ -122,6 +122,26 @@ extern "C" {
                                            // Should only be used if game has a specific
                                            // way to shutdown the game from a menu item or similar.
 
+#define RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL 8
+                                           // const unsigned * --
+                                           // Gives a hint to the frontend how demanding this implementation
+                                           // is on a system. E.g. reporting a level of 2 means
+                                           // this implementation should run decently on all frontends
+                                           // of level 2 and up.
+                                           //
+                                           // It can be used by the frontend to potentially warn
+                                           // about too demanding implementations.
+                                           // 
+                                           // The levels are "floating", but roughly defined as:
+                                           // 1: Low-powered devices such as Raspberry Pi, smart phones, tablets, etc.
+                                           // 2: Medium-spec consoles, such as PS3/360, with sub-par CPUs.
+                                           // 3: Modern desktop/laptops with reasonably powerful CPUs.
+                                           // 4: High-end desktops with very powerful CPUs.
+                                           //
+                                           // This function can be called on a per-game basis,
+                                           // as certain games an implementation can play might be
+                                           // particularily demanding.
+
 struct retro_message
 {
    const char *msg;        // Message to be displayed.