diff --git a/BPmono.ttf b/BPmono.ttf
new file mode 100755
index 0000000..e6bb690
Binary files /dev/null and b/BPmono.ttf differ
diff --git a/src/Box.cpp b/src/Box.cpp
index 5e9ba12..1a7323b 100644
--- a/src/Box.cpp
+++ b/src/Box.cpp
@@ -107,6 +107,11 @@ glm::vec2 Box::get_north() const
     return glm::vec2(get_x() + get_w() / 2, get_y());
 }
 
+glm::vec2 Box::get_ne() const
+{
+    return glm::vec2(get_right(), get_y());
+}
+
 glm::vec2 Box::get_east() const
 {
     return glm::vec2(get_right(), get_y() + get_h() / 2);
@@ -138,6 +143,11 @@ void Box::set_north(const glm::vec2& n)
     move(n - get_north());
 }
 
+void Box::set_ne(const glm::vec2& ne)
+{
+    move(ne - get_ne());
+}
+
 void Box::set_east(const glm::vec2& e)
 {
     move(e - get_east());
diff --git a/src/Box.hpp b/src/Box.hpp
index 330ed56..86ed636 100644
--- a/src/Box.hpp
+++ b/src/Box.hpp
@@ -34,12 +34,14 @@ struct Box
     void set_left(float);
     glm::vec2 get_nw() const;
     glm::vec2 get_north() const;
+    glm::vec2 get_ne() const;
     glm::vec2 get_east() const;
     glm::vec2 get_south() const;
     glm::vec2 get_west() const;
     glm::vec2 get_center() const;
     void set_nw(const glm::vec2&);
     void set_north(const glm::vec2&);
+    void set_ne(const glm::vec2&);
     void set_east(const glm::vec2&);
     void set_south(const glm::vec2&);
     void set_west(const glm::vec2&);
diff --git a/src/Configuration.cpp b/src/Configuration.cpp
index 7eb58e4..bbab862 100644
--- a/src/Configuration.cpp
+++ b/src/Configuration.cpp
@@ -23,7 +23,7 @@ void Configuration::set_defaults()
         {"left", "left"},
         {"pause", "enter"},
         {"fullscreen", {"ALT", "enter"}},
-        {"show-fps", {"CTRL", "f"}}
+        {"toggle-framerate", {"CTRL", "f"}}
     };
     sys_config["path"] = {
         {"screenshots", "."},
@@ -31,7 +31,7 @@ void Configuration::set_defaults()
     };
     sys_config["display"] = {
         {"dimensions", {640, 480}},
-        {"fps", 60},
+        {"framerate", 60},
         {"title", "sfw"}
     };
     sys_config["recording"] = {
diff --git a/src/Display.cpp b/src/Display.cpp
index 7e013a0..3d0aba6 100644
--- a/src/Display.cpp
+++ b/src/Display.cpp
@@ -1,7 +1,10 @@
 #include "Display.hpp"
 #include "Game.hpp"
 
-Display::Display(Node* parent) : Node(parent) {}
+Display::Display(Node* parent) : Node(parent)
+{
+    get_delegate().subscribe(&Display::respond, this);
+}
     
 glm::ivec2 Display::get_window_size()
 {
@@ -88,3 +91,25 @@ SDL_Surface* Display::get_screen_surface_from_pixels(
     }
     return surface;
 }
+
+void Display::respond(SDL_Event& event)
+{
+    if (get_delegate().compare(event, "fullscreen"))
+    {
+        toggle_fullscreen();
+    }
+}
+
+void Display::toggle_fullscreen()
+{
+    if (SDL_GetWindowFlags(get_root()->get_window()) & SDL_WINDOW_FULLSCREEN)
+    {
+        SDL_Log("fullscreen requested");
+        SDL_SetWindowFullscreen(get_root()->window, 0);
+    }
+    else
+    {
+        SDL_Log("exit fullscreen requested");
+        SDL_SetWindowFullscreen(get_root()->get_window(), SDL_WINDOW_FULLSCREEN);
+    }
+}
diff --git a/src/Display.hpp b/src/Display.hpp
index ade58f9..ed97251 100644
--- a/src/Display.hpp
+++ b/src/Display.hpp
@@ -28,6 +28,8 @@ struct Display : Node
     void get_screen_pixels(unsigned char*, int, int, int = 0, int = 0);
     SDL_Surface* get_screen_surface();
     SDL_Surface* get_screen_surface_from_pixels(unsigned char*, bool);
+    void respond(SDL_Event&);
+    void toggle_fullscreen();
 
 };
 
diff --git a/src/Game.cpp b/src/Game.cpp
index deb4efd..b3a091d 100644
--- a/src/Game.cpp
+++ b/src/Game.cpp
@@ -1,16 +1,53 @@
 #include "Game.hpp"
 
-// FPSIndicator::FPSIndicator(Node* parent) : Node(parent) {}
+FramerateIndicator::FramerateIndicator(Node* parent) : Sprite(parent)
+{
+    get_delegate().subscribe(&FramerateIndicator::respond, this);
+    hide();
+}
 
-// FPSIndicator::update()
-// {
-    
-// }
+void FramerateIndicator::respond(SDL_Event& event)
+{
+    if (get_delegate().compare(event, "toggle-framerate"))
+    {
+        toggle_hidden();
+    }
+}
+
+SDL_Surface* FramerateIndicator::get_surface()
+{
+    std::string padded = sfw::pad(get_root()->frame_count_this_second, 2);
+    SDL_Surface* shaded = TTF_RenderText_Shaded(
+        get_root()->bp_mono_font, padded.c_str(), {0, 0, 0}, {255, 255, 255});
+    // SDL_Surface* converted = SDL_ConvertSurfaceFormat(
+    //     shaded, SDL_PIXELFORMAT_ARGB8888, 0);
+    // SDL_Surface* flipped = zoomSurface(converted, 1, -1, SMOOTHING_OFF);
+    // SDL_FreeSurface(shaded);
+    // SDL_FreeSurface(converted);
+    if (!shaded)
+    {
+        get_root()->print_sdl_error("Could not create text");
+    }
+    return shaded;
+}
+
+void FramerateIndicator::refresh()
+{
+    if (!is_hidden() && get_root()->bp_mono_font != NULL)
+    {
+        unload();
+        SDL_Surface* surface = get_surface();
+        SDL_Texture* texture = SDL_CreateTextureFromSurface(get_root()->get_renderer(), surface);
+        add_frame(texture);
+        SDL_FreeSurface(surface);
+        box.set_ne(get_display().get_window_box().get_ne());
+    }
+}
 
 Game::Game()
 {
     frame_length_history.reserve(5000);
-    set_framerate(get_configuration()["display"]["fps"]);
+    set_framerate(get_configuration()["display"]["framerate"]);
     delegate.subscribe(&Game::handle_quit_event, this, SDL_QUIT);
     SDL_Log("GLEW %s", glewGetString(GLEW_VERSION));
     putenv("SDL_VIDEO_X11_LEGACY_FULLSCREEN=0");
@@ -58,6 +95,10 @@ Game::Game()
         SDL_Log("initialized SDL ttf %d.%d.%d", SDL_TTF_MAJOR_VERSION,
                 SDL_TTF_MINOR_VERSION, SDL_TTF_PATCHLEVEL);
     }
+    if ((bp_mono_font = TTF_OpenFont("BPmono.ttf", 14)) == NULL)
+    {
+        print_error("Could not load BPmono.ttf");
+    }
 #if !defined(__EMSCRIPTEN__)
     if (Mix_Init(MIX_INIT_FLAC) == 0)
     {
@@ -452,11 +493,23 @@ void Game::frame(float ticks)
         recorder.update();
         delegate.dispatch();
         update();
+        framerate_indicator.update();
+        if (!is_gl_context)
+        {
+            SDL_RenderPresent(renderer);
+        }
         if (frame_time_overflow > frame_length)
         {
             // SDL_Log("%i frame(s) dropped", ((int) (frame_time_overflow / frame_length)));
             frame_time_overflow = 0;
         }
+        frame_count_this_second++;
+        if (ticks - last_frame_count_timestamp >= 1000)
+        {
+            framerate_indicator.refresh();
+            last_frame_count_timestamp = ticks;
+            frame_count_this_second = 0;
+        }
     }
     // std::cout << std::endl;
 }
@@ -485,13 +538,13 @@ glm::vec2 Game::weight(glm::vec2 motion)
     return glm::vec2(weight(motion.x), weight(motion.y));
 }
 
-void Game::set_framerate(int fps)
+void Game::set_framerate(int f)
 {
-    if (fps < 1)
+    if (f < 1)
     {
-        fps = 1;
+        f = 1;
     }
-    framerate = fps;
+    framerate = f;
     frame_length = 1000.0 / framerate;
 }
 
@@ -519,6 +572,7 @@ void Game::quit()
     }
     if (TTF_WasInit())
     {
+        TTF_CloseFont(bp_mono_font);
         TTF_Quit();
     }
     Mix_CloseAudio();
diff --git a/src/Game.hpp b/src/Game.hpp
index 537c2b4..7749be7 100644
--- a/src/Game.hpp
+++ b/src/Game.hpp
@@ -27,19 +27,19 @@
 #endif
 
 #include "Node.hpp"
-#include "Configuration.hpp"
-#include "Delegate.hpp"
-#include "Display.hpp"
-#include "Recorder.hpp"
 #include "Input.hpp"
-// #include "Sprite.hpp"
+#include "Recorder.hpp"
+#include "Sprite.hpp"
 
-// struct FPSIndicator : Sprite
-// {
+struct FramerateIndicator : Sprite
+{
 
-//     FPSIndicator(Node*);
+    FramerateIndicator(Node*);
+    void respond(SDL_Event&);
+    SDL_Surface* get_surface();
+    void refresh();
 
-// };
+};
 
 struct Game : Node
 {
@@ -54,9 +54,9 @@ struct Game : Node
     SDL_GLContext glcontext = NULL;
     // 768, 432
     // 864, 486
-    int framerate, ticks, last_frame_length;
-    float frame_length = 1000.0 / 60.0, frame_time_overflow = 0,
-        last_frame_timestamp, emscripten_previous_time;
+    int frame_count_this_second = 0, framerate, ticks, last_frame_length;
+    float frame_length = 1000.0 / 60.0, frame_time_overflow = 0, last_frame_timestamp,
+        last_frame_count_timestamp, emscripten_previous_time;
     bool done = false, show_framerate = true, is_gl_context = true;
     Configuration configuration = Configuration(this);
     Delegate delegate = Delegate(this);
@@ -64,6 +64,8 @@ struct Game : Node
     Recorder recorder = Recorder(this);
     Input input = Input(this);
     std::vector<float> frame_length_history;
+    TTF_Font* bp_mono_font = NULL;
+    FramerateIndicator framerate_indicator = FramerateIndicator(this);
 
     Game();
     ~Game();
@@ -103,6 +105,4 @@ void loop(void*);
 
 #endif
 
-#include "Sprite.hpp"
-
 #endif
diff --git a/src/Input.hpp b/src/Input.hpp
index df3c5d0..04e75d2 100644
--- a/src/Input.hpp
+++ b/src/Input.hpp
@@ -9,7 +9,6 @@
 #include "SDL.h"
 
 #include "Node.hpp"
-#include "Delegate.hpp"
 
 struct KeyCombination
 {
diff --git a/src/Node.cpp b/src/Node.cpp
index 76f6011..a1fe1fe 100644
--- a/src/Node.cpp
+++ b/src/Node.cpp
@@ -1,7 +1,5 @@
 #include "Node.hpp"
 #include "Game.hpp"
-// #include "Display.hpp"
-// #include "Delegate.hpp"
 
 Node::Node() : Node(NULL) {}
 
diff --git a/src/Node.hpp b/src/Node.hpp
index 51c526d..0edab5f 100644
--- a/src/Node.hpp
+++ b/src/Node.hpp
@@ -11,7 +11,6 @@
 struct Game;
 struct Delegate;
 struct Display;
-struct TimeFilter;
 
 struct Node
 {
@@ -35,4 +34,8 @@ struct Node
 
 };
 
+#include "Configuration.hpp"
+#include "Delegate.hpp"
+#include "Display.hpp"
+
 #endif
diff --git a/src/Recorder.cpp b/src/Recorder.cpp
index 6b42572..c1c0d2e 100644
--- a/src/Recorder.cpp
+++ b/src/Recorder.cpp
@@ -1,4 +1,3 @@
-#include "Game.hpp"
 #include "Recorder.hpp"
 #include "gif-h/gif.h"
 
diff --git a/src/Recorder.hpp b/src/Recorder.hpp
index 4b214e0..b288bfe 100644
--- a/src/Recorder.hpp
+++ b/src/Recorder.hpp
@@ -6,8 +6,10 @@
 #include <thread>
 #include <functional>
 #include <cstdlib>
+#include <fstream>
 
 #include "SDL.h"
+#include "SDL_mixer.h"
 
 #define GLM_ENABLE_EXPERIMENTAL
 #include "glm/ext.hpp"
@@ -15,9 +17,8 @@
 #include "json/json.hpp"
 
 #include "filesystem.hpp"
+#include "Node.hpp"
 #include "Animation.hpp"
-#include "Delegate.hpp"
-#include "Display.hpp"
 #include "extension.hpp"
 
 struct Stash
@@ -67,4 +68,6 @@ struct Recorder : Node
 
 void process_audio(void*, Uint8*, int);
 
+#include "Game.hpp"
+
 #endif
diff --git a/src/Sprite.cpp b/src/Sprite.cpp
index b8b5ef1..8fd914a 100644
--- a/src/Sprite.cpp
+++ b/src/Sprite.cpp
@@ -136,17 +136,22 @@ void Sprite::advance_frame()
 
 void Sprite::hide()
 {
-    is_hidden = true;
+    hidden = true;
 }
 
 void Sprite::unhide()
 {
-    is_hidden = false;
+    hidden = false;
 }
 
 void Sprite::toggle_hidden()
 {
-    is_hidden = !is_hidden;
+    hidden = !hidden;
+}
+
+bool Sprite::is_hidden() const
+{
+    return hidden;
 }
 
 void Sprite::set_step(glm::vec2 s)
@@ -227,7 +232,7 @@ void Sprite::update()
         move(step);
         frame_animation.update();
         blink_animation.update();
-        if (is_loaded() && !is_hidden && get_current_frameset().get_frame_count())
+        if (is_loaded() && !is_hidden() && get_current_frameset().get_frame_count())
         {
             int index = get_current_frameset().get_current_frame_index();
             SDL_Texture* texture = frames[index];
diff --git a/src/Sprite.hpp b/src/Sprite.hpp
index 74797b2..2258f0a 100644
--- a/src/Sprite.hpp
+++ b/src/Sprite.hpp
@@ -11,11 +11,11 @@
 #include <SDL_image.h>
 
 #include "Node.hpp"
-#include "Game.hpp"
 #include "Box.hpp"
 #include "Animation.hpp"
 #include "extension.hpp"
 
+struct Game;
 struct Frameset;
 
 struct Sprite : Node
@@ -26,7 +26,7 @@ struct Sprite : Node
     Box box;
     Animation frame_animation = Animation(&Sprite::advance_frame, this);
     Animation blink_animation = Animation(&Sprite::toggle_hidden, this, 500);
-    bool is_hidden = false;
+    bool hidden = false;
     glm::vec2 step = {0, 0};
     Uint8 alpha_mod = 255;
     std::map<std::string, Frameset> framesets;
@@ -51,6 +51,7 @@ struct Sprite : Node
     void hide();
     void unhide();
     void toggle_hidden();
+    bool is_hidden() const;
     void set_step(glm::vec2);
     float get_w() const;
     float get_h() const;
@@ -101,4 +102,6 @@ struct Frameset
 
 };
 
+#include "Game.hpp"
+
 #endif
diff --git a/src/extension.hpp b/src/extension.hpp
index e9138a5..1e6ee57 100644
--- a/src/extension.hpp
+++ b/src/extension.hpp
@@ -7,6 +7,7 @@
 #include <sstream>
 #include <algorithm>
 #include <iomanip>
+#include <stdexcept>
 
 #define GLM_ENABLE_EXPERIMENTAL
 #include "glm/trigonometric.hpp"
@@ -39,6 +40,38 @@ namespace sfw
         padded << end;
         return padded.str();
     }
+
+    // from https://stackoverflow.com/a/30312659/1256386
+    template <typename IntType>
+    std::vector<IntType> range(IntType start, IntType stop, IntType step)
+    {
+        if (step == IntType(0))
+        {
+            throw std::invalid_argument("step for range must be non-zero");
+        }
+        std::vector<IntType> result;
+        IntType i = start;
+        while ((step > 0) ? (i < stop) : (i > stop))
+        {
+            result.push_back(i);
+            i += step;
+        }
+        return result;
+    }
+
+    // from https://stackoverflow.com/a/30312659/1256386
+    template <typename IntType>
+    std::vector<IntType> range(IntType start, IntType stop)
+    {
+        return range(start, stop, IntType(1));
+    }
+
+    // from https://stackoverflow.com/a/30312659/1256386
+    template <typename IntType>
+    std::vector<IntType> range(IntType stop)
+    {
+        return range(IntType(0), stop, IntType(1));
+    }
 }
 
 std::ostream& operator<<(std::ostream&, const glm::vec2&);