Add lutro.timer.getFPS()

lutro.c

@@ -47,7 +47,10 @@ lutro_settings_t settings = {
    .live_enable = 0,
    .live_call_load = 0,
    .input_cb = NULL,
-   .delta = 0
+   .delta = 0,
+   .deltaCounter = 0,
+   .frameCounter = 0,
+   .fps = 0
 };
 
 #if 0
@@ -539,6 +542,14 @@ void lutro_gamepadevent(lua_State* L)
 void lutro_run(double delta)
 {
    settings.delta = delta;
+   settings.deltaCounter += delta;
+   settings.frameCounter += 1;
+   if (settings.deltaCounter >= 1000.0) {
+      settings.fps = settings.frameCounter;
+      settings.frameCounter = 0;
+      settings.deltaCounter = 0;
+   }
+
 #ifdef HAVE_INOTIFY
    if (settings.live_enable)
       lutro_live_update(L);

lutro.h

@@ -26,6 +26,9 @@ typedef struct lutro_settings_t {
    char gamedir[PATH_MAX_LENGTH];
    char identity[PATH_MAX_LENGTH];
    double delta;
+   double deltaCounter;
+   int frameCounter;
+   int fps;
 } lutro_settings_t;
 
 extern lutro_settings_t settings;

test/main.lua

@@ -64,6 +64,9 @@ function lutro.draw()
 	-- Testing the keyboard/joystick pressed event.
 	lutro.graphics.print(joystickButton, 50, 50)
 	lutro.graphics.print(keypressed, 500, 400)
+
+	local fps = lutro.timer.getFPS()
+	lutro.graphics.print(fps, 500, 500)
 end
 
 function lutro.joystickpressed(joystick, button)

timer.c

@@ -9,6 +9,7 @@ int lutro_timer_preload(lua_State *L)
    static luaL_Reg gfx_funcs[] =  {
       { "getTime", timer_getTime },
       { "getDelta", timer_getDelta },
+      { "getFPS", timer_getFPS },
       {NULL, NULL}
    };
 
@@ -43,3 +44,15 @@ int timer_getDelta(lua_State *L)
 
    return 1;
 }
+
+/**
+ * lutro.timer.getFPS()
+ *
+ * @see https://love2d.org/wiki/love.timer.getFPS
+ */
+int timer_getFPS(lua_State *L)
+{
+   lua_pushnumber(L, settings.fps);
+
+   return 1;
+}

timer.h

@@ -12,5 +12,6 @@ int lutro_timer_preload(lua_State *L);
 
 int timer_getTime(lua_State *L);
 int timer_getDelta(lua_State *L);
+int timer_getFPS(lua_State *L);
 
 #endif // TIMER_H