Add timers and ability to set a target fps for the application (#36)

* working on windows

* minor fix

* working on macosx

* Oops! I reversed resolution and frequency on macos

* working on X11

* working on wayland

* update the readme

* format the readme

Co-authored-by: Carlos Aragones <>

CMakeLists.txt

@@ -14,6 +14,7 @@ set(SrcLib
     src/MiniFB_cpp.cpp
     src/MiniFB_internal.c
     src/MiniFB_internal.h
+    src/MiniFB_timer.c
     src/WindowData.h
 )
 
@@ -34,11 +35,13 @@ set(SrcMacOSX
 set(SrcWayland
     src/wayland/WaylandMiniFB.c
     src/wayland/WindowData_Way.h
+    src/MiniFB_linux.c
 )
 
 set(SrcX11
     src/x11/X11MiniFB.c
     src/x11/WindowData_X11.h
+    src/MiniFB_linux.c
 )
 
 # Avoid RelWithDebInfo and MinSizeRel
@@ -52,6 +55,12 @@ if(NOT CMAKE_BUILD_TYPE)
     message(STATUS "Build type not specified: Use Release by default")
 endif(NOT CMAKE_BUILD_TYPE)
 
+# Set features
+#--------------------------------------
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
 # Set GCC/Clang flags
 #--------------------------------------
 if (NOT MSVC)
@@ -78,7 +87,6 @@ if (NOT MSVC)
     add_compile_options("$<$<CONFIG:Debug>:-g>")
     add_compile_options("$<IF:$<CONFIG:Debug>,-O0,-O2>")
     set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -pedantic -Wno-switch -Wno-unused-function -Wno-implicit-fallthrough")
-    set (CMAKE_CXX_FLAGS "${CMAKE_C_FLAGS} -std=c++11")
     set (CMAKE_OBJC_FLAGS "${CMAKE_C_FLAGS}")
     set (CMAKE_OBJCXX_FLAGS "${CMAKE_CXX_FLAGS}")
 endif()

README.md

@@ -1,117 +1,173 @@
-MiniFB
+# MiniFB
-======
 
 MiniFB (Mini FrameBuffer) is a small cross platform library that makes it easy to render (32-bit) pixels in a window. An example is the best way to show how it works:
 
-	struct mfb_window *window = mfb_open_ex("my display", 800, 600, WF_RESIZABLE);
+```c
-	if (!window)
+struct mfb_window *window = mfb_open_ex("my display", 800, 600, WF_RESIZABLE);
-		return 0;
+if (!window)
+	return 0;
 
-	for (;;)
+for (;;)
-	{
+{
-		int state;
+	int state;
 
-		// TODO: add some fancy rendering to the buffer of size 800 * 600
+	// TODO: add some fancy rendering to the buffer of size 800 * 600
 
-		state = mfb_update(buffer);
+	state = mfb_update(buffer);
 
-		if (state < 0)
+	if (state < 0)
-			break;
+		break;
-	}
+}
+```
 
 
-Furthermore, you can add callbacks to the windows:
+Furthermore, you can _add callbacks to the windows_:
 
-	void active(struct mfb_window *window, bool isActive) {
+```c
-		...
+void active(struct mfb_window *window, bool isActive) {
-	}
-
-	void resize(struct mfb_window *window, int width, int height) {
-		...
-		// Optionally you can also change the viewport size
-		mfb_set_viewport(window, x, y, width, height);
-	}
-
-	void keyboard(struct mfb_window *window, mfb_key key, mfb_key_mod mod, bool isPressed) {
-		...
-		// Remember to close the window in some way
-		if(key == KB_KEY_ESCAPE) {
-			mfb_close(window);
-		}
-
-		fprintf(stdout, "%s > keyboard: key: %s (pressed: %d) [key_mod: %x]\n", window_title, mfb_get_key_name(key), isPressed, mod);
-
-	}
-
-	void char_input(struct mfb_window *window, unsigned int charCode) {
-		...
-	}
-
-	void mouse_btn(struct mfb_window *window, mfb_mouse_button button, mfb_key_mod mod, bool isPressed) {
-		...
-	}
-
-	// Use wisely this event. It can be sent too often
-	void mouse_move(struct mfb_window *window, int x, int y) {
-		...
-	}
-
-	// Mouse wheel
-	void mouse_scroll(struct mfb_window *window, mfb_key_mod mod, float deltaX, float deltaY) {
-		...
-	}
-
-	struct mfb_window *window = mfb_open_ex("my display", 800, 600, WF_RESIZABLE);
-	if (!window)
-		return 0;
-
-	mfb_set_active_callback(window, active);
-	mfb_set_resize_callback(window, resize);
-	mfb_set_keyboard_callback(window, keyboard);
-	mfb_set_char_input_callback(window, char_input);
-	mfb_set_mouse_button_callback(window, mouse_btn);
-	mfb_set_mouse_move_callback(window, mouse_move);
-	mfb_set_mouse_scroll_callback(window, mouse_scroll);
-
-
-Additionally you can set data per window and recover it
-
-	mfb_set_user_data(window, (void *) myData);
 	...
-	myData = (someCast *) mfb_get_user_data(window);
+}
+
+void resize(struct mfb_window *window, int width, int height) {
+	...
+	// Optionally you can also change the viewport size
+	mfb_set_viewport(window, x, y, width, height);
+}
+
+void keyboard(struct mfb_window *window, mfb_key key, mfb_key_mod mod, bool isPressed) {
+	...
+	// Remember to close the window in some way
+	if(key == KB_KEY_ESCAPE) {
+		mfb_close(window);
+	}
+
+	fprintf(stdout, "%s > keyboard: key: %s (pressed: %d) [key_mod: %x]\n", window_title, mfb_get_key_name(key), isPressed, mod);
+
+}
+
+void char_input(struct mfb_window *window, unsigned int charCode) {
+	...
+}
+
+void mouse_btn(struct mfb_window *window, mfb_mouse_button button, mfb_key_mod mod, bool isPressed) {
+	...
+}
+
+// Use wisely this event. It can be sent too often
+void mouse_move(struct mfb_window *window, int x, int y) {
+	...
+}
+
+// Mouse wheel
+void mouse_scroll(struct mfb_window *window, mfb_key_mod mod, float deltaX, float deltaY) {
+	...
+}
+
+struct mfb_window *window = mfb_open_ex("my display", 800, 600, WF_RESIZABLE);
+if (!window)
+	return 0;
+
+mfb_set_active_callback(window, active);
+mfb_set_resize_callback(window, resize);
+mfb_set_keyboard_callback(window, keyboard);
+mfb_set_char_input_callback(window, char_input);
+mfb_set_mouse_button_callback(window, mouse_btn);
+mfb_set_mouse_move_callback(window, mouse_move);
+mfb_set_mouse_scroll_callback(window, mouse_scroll);
+```
 
 
-Finally, you can get information about the events in the window directly:
+Additionally you can _set data per window and recover it_:
 
-	bool                mfb_is_window_active(struct mfb_window *window);
+```c
-	
+mfb_set_user_data(window, (void *) myData);
-	unsigned            mfb_get_window_width(struct mfb_window *window);
+...
-	unsigned            mfb_get_window_height(struct mfb_window *window);
+myData = (someCast *) mfb_get_user_data(window);
+```
 
-	int                 mfb_get_mouse_x(struct mfb_window *window);             // Last mouse pos X
-	int                 mfb_get_mouse_y(struct mfb_window *window);             // Last mouse pos Y
 
-	float               mfb_get_mouse_scroll_x(struct mfb_window *window);      // Mouse wheel X as a sum. When you call this function it resets.
+Finally, you can _get information about the events in the window directly_:
-	float               mfb_get_mouse_scroll_y(struct mfb_window *window);      // Mouse wheel Y as a sum. When you call this function it resets.
 
-	const uint8_t *     mfb_get_mouse_button_buffer(struct mfb_window *window); // One byte for every button. Press (1), Release 0. (up to 8 buttons)
+```c
+bool                mfb_is_window_active(struct mfb_window *window);
 
-	const uint8_t *     mfb_get_key_buffer(struct mfb_window *window);          // One byte for every key. Press (1), Release 0.
+unsigned            mfb_get_window_width(struct mfb_window *window);
+unsigned            mfb_get_window_height(struct mfb_window *window);
+
+int                 mfb_get_mouse_x(struct mfb_window *window);             // Last mouse pos X
+int                 mfb_get_mouse_y(struct mfb_window *window);             // Last mouse pos Y
+
+float               mfb_get_mouse_scroll_x(struct mfb_window *window);      // Mouse wheel X as a sum. When you call this function it resets.
+float               mfb_get_mouse_scroll_y(struct mfb_window *window);      // Mouse wheel Y as a sum. When you call this function it resets.
+
+const uint8_t *     mfb_get_mouse_button_buffer(struct mfb_window *window); // One byte for every button. Press (1), Release 0. (up to 8 buttons)
+
+const uint8_t *     mfb_get_key_buffer(struct mfb_window *window);          // One byte for every key. Press (1), Release 0.
+```
 
 
 First the code creates window with the mfb_open call that is used to display the data, next it's the applications responsibility to allocate a buffer (which has to be at least the size of the window and in 32-bit) Next when calling mfb_update function the buffer will be copied over to the window and displayed. Currently the mfb_update will return -1 if ESC key is pressed but later on it will support to return a key code for a pressed button. See https://github.com/emoon/minifb/blob/master/tests/noise.c for a complete example
 
 MiniFB has been tested on Windows, Mac OS X and Linux but may of course have trouble depending on your setup. Currently the code will not do any converting of data if not a proper 32-bit display can be created.
 
-Build instructions
+
-------------------
+**Extra: Timers and target FPS**
+
+You can create timers for your own purposes.
+
+```c
+struct mfb_timer *  mfb_timer_create();
+void                mfb_timer_destroy(struct mfb_timer *tmr);
+
+void                mfb_timer_reset(struct mfb_timer *tmr);
+double              mfb_timer_now(struct mfb_timer *tmr);
+double              mfb_timer_delta(struct mfb_timer *tmr);
+
+double              mfb_timer_get_frequency();
+double              mfb_timer_get_resolution();
+```
+
+Furthermore you can set a target fps for the application. The default is 60 frames per second. 
+
+```c
+void                mfb_set_target_fps(uint32_t fps);
+```
+
+This avoid the problem of update too fast the window collapsing the redrawing in fast processors.
+
+To use this you need to call the function:
+
+```c
+bool                mfb_wait_sync(struct mfb_window *window);
+```
+
+_Example_:
+
+```c
+do {
+	int         i;
+	mfb_update_state state;
+
+	// TODO: add some awesome rendering to the buffer
+
+	state = mfb_update(window, g_buffer);
+	if (state != STATE_OK) {
+		window = 0x0;
+		break;
+	}
+} while(mfb_wait_sync(window));
+```
+
+Note that if you have several windows running on the same thread it makes no sense to wait them all...
+
+
+## Build instructions
 
 MiniFB uses tundra https://github.com/deplinenoise/tundra as build system and is required to build the code as is but not many changes should be needed if you want to use it directly in your own code.
 
 You can also use CMake as build system.
 
-Mac
+### Mac
----
 
 Cocoa and clang is assumed to be installed on the system (downloading latest XCode + installing the command line tools should do the trick) then to build run: tundra2 macosx-clang-debug and you should be able to run the noise example (t2-output/macosx-clang-debug-default/noise)
 
@@ -120,44 +176,49 @@ To enable it just compile defining the preprocessor macro USE_METAL_API.
 
 If you use CMake just enable the flag:
 
-	mkdir build
+```
-	cd build
+mkdir build
-	cmake .. -DUSE_METAL_API=ON
+cd build
+cmake .. -DUSE_METAL_API=ON
+```
 
 or if you don't want to use Metal API:
 
-	mkdir build
+```
-	cd build
+mkdir build
-	cmake .. -DUSE_METAL_API=OFF
+cd build
+cmake .. -DUSE_METAL_API=OFF
+```
 
 
-Windows
+### Windows
--------
 
 Visual Studio (ver 2012 express has been tested) tools needed (using the vcvars32.bat (for 32-bit) will set up the enviroment) to build run: tundra2 win32-msvc-debug and you should be able to run noise in t2-output/win32-msvc-debug-default/noise.exe
 
 If you use CMake the Visual Studio project will be generated (2015, 2017 and 2019 have been tested).
 
 
-x11 (FreeBSD, Linux, *nix)
+### x11 (FreeBSD, Linux, *nix)
---------------------------
 
 gcc and x11-dev libs needs to be installed. To build the code run tundra2 x11-gcc-debug and you should be able to run t2-output/x11-gcc-debug-default/noise
 
 If you use CMake just disable the flag:
 
-	mkdir build
+```
-	cd build
+mkdir build
-	cmake .. -DUSE_WAYLAND_API=OFF
+cd build
+cmake .. -DUSE_WAYLAND_API=OFF
+```
 
 
-wayland (Linux)
+### Wayland (Linux)
---------------------------
 
 Depends on gcc and wayland-client and wayland-cursor. Built using the wayland-gcc variants.
 
 If you use CMake just enable the flag:
 
-	mkdir build
+```
-	cd build
+mkdir build
-	cmake .. -DUSE_WAYLAND_API=ON
+cd build
+cmake .. -DUSE_WAYLAND_API=ON
+```

include/MiniFB.h

@@ -56,6 +56,17 @@ float               mfb_get_mouse_scroll_y(struct mfb_window *window);      // M
 const uint8_t *     mfb_get_mouse_button_buffer(struct mfb_window *window); // One byte for every button. Press (1), Release 0. (up to 8 buttons)
 const uint8_t *     mfb_get_key_buffer(struct mfb_window *window);          // One byte for every key. Press (1), Release 0.
 
+void                mfb_set_target_fps(uint32_t fps);
+bool                mfb_wait_sync(struct mfb_window *window);
+
+struct mfb_timer *  mfb_timer_create();
+void                mfb_timer_destroy(struct mfb_timer *tmr);
+void                mfb_timer_reset(struct mfb_timer *tmr);
+double              mfb_timer_now(struct mfb_timer *tmr);
+double              mfb_timer_delta(struct mfb_timer *tmr);
+double              mfb_timer_get_frequency();
+double              mfb_timer_get_resolution();
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
 #ifdef __cplusplus

include/MiniFB_enums.h

@@ -172,6 +172,7 @@ typedef enum {
 
 // Opaque pointer
 struct mfb_window;
+struct mfb_timer;
 
 // Event callbacks
 typedef void(*mfb_active_func)(struct mfb_window *window, bool isActive);

src/MiniFB_internal.h

@@ -6,6 +6,13 @@
 #define kCall(func, ...)    if(window_data && window_data->func) window_data->func((struct mfb_window *) window_data, __VA_ARGS__);
 #define kUnused(var)        (void) var;
 
+typedef struct mfb_timer {
+    int64_t     start_time;
+    int64_t     delta_counter;
+    uint64_t    time;
+} mfb_timer;
+
+
 #if defined(__cplusplus)
 extern "C" {
 #endif

src/MiniFB_linux.c

@@ -0,0 +1,32 @@
+#include <time.h>
+#include <MiniFB.h>
+
+extern double   g_timer_frequency;
+extern double   g_timer_resolution;
+
+#define kClock      CLOCK_MONOTONIC
+//#define kClock      CLOCK_REALTIME
+
+uint64_t 
+mfb_timer_tick() {
+    struct timespec time;
+
+    if (clock_gettime(kClock, &time) != 0) {
+        return 0.0;
+    }
+
+    return time.tv_sec * 1e+9 + time.tv_nsec;
+}
+
+void 
+mfb_timer_init() {
+    struct timespec res;
+
+    if (clock_getres(kClock, &res) != 0) {
+        g_timer_frequency = 1e+9;
+    }
+    else {
+        g_timer_frequency = res.tv_sec + res.tv_nsec * 1e+9;
+    }
+    g_timer_resolution = 1.0 / g_timer_frequency;
+}

src/MiniFB_timer.c

@@ -0,0 +1,102 @@
+#include "MiniFB.h"
+#include "MiniFB_internal.h"
+#include <stdlib.h>
+
+//-------------------------------------
+double      g_timer_frequency;
+double      g_timer_resolution;
+double      g_time_for_frame = 1.0 / 60.0;
+
+//-------------------------------------
+extern uint64_t mfb_timer_tick();
+extern void mfb_timer_init();
+
+//-------------------------------------
+void
+mfb_set_target_fps(uint32_t fps) {
+    if(fps == 0) {
+        g_time_for_frame = 0;
+    }
+    else {
+        g_time_for_frame = 1.0 / fps;
+    }
+}
+
+//-------------------------------------
+struct mfb_timer *
+mfb_timer_create() {
+    static int  once = 1;
+    mfb_timer   *tmr;
+
+    if(once) {
+        once = 0;
+        mfb_timer_init();
+    }
+
+    tmr = malloc(sizeof(mfb_timer));
+    mfb_timer_reset(tmr);
+
+    return tmr;
+}
+
+//-------------------------------------
+void
+mfb_timer_destroy(struct mfb_timer *tmr) {
+    if(tmr != 0x0) {
+        free(tmr);
+    }
+}
+
+//-------------------------------------
+void
+mfb_timer_reset(struct mfb_timer *tmr) {
+    if(tmr == 0x0) 
+        return;
+
+    tmr->start_time    = mfb_timer_tick();
+    tmr->delta_counter = tmr->start_time;
+    tmr->time          = 0;
+}
+
+//-------------------------------------
+double
+mfb_timer_now(struct mfb_timer *tmr) {
+    uint64_t    counter;
+
+    if(tmr == 0x0) 
+        return 0.0;
+
+    counter         = mfb_timer_tick();
+    tmr->time      += (counter - tmr->start_time);
+    tmr->start_time = counter;
+
+    return tmr->time * g_timer_resolution;
+}
+
+//-------------------------------------
+double
+mfb_timer_delta(struct mfb_timer *tmr) {
+    int64_t     counter;
+    uint64_t    delta;
+
+    if(tmr == 0x0) 
+        return 0.0;
+
+    counter            = mfb_timer_tick();
+    delta              = (counter - tmr->delta_counter);
+    tmr->delta_counter = counter;
+
+    return delta * g_timer_resolution;
+}
+
+//-------------------------------------
+double
+mfb_timer_get_frequency() {
+    return g_timer_frequency;
+}
+
+//-------------------------------------
+double
+mfb_timer_get_resolution() {
+    return g_timer_resolution;
+}

src/macosx/MacMiniFB.m

@@ -10,6 +10,8 @@
 #include <MetalKit/MetalKit.h>
 #endif
 #include <unistd.h>
+#include <sched.h>
+#include <mach/mach_time.h>
 
 void init_keycodes();
 
@@ -250,6 +252,7 @@ mfb_open_ex(const char *title, unsigned width, unsigned height, unsigned flags)
     [window_data_osx->window setAcceptsMouseMovedEvents:YES];
 
     [window_data_osx->window center];
+    window_data_osx->timer = mfb_timer_create();
 
     [NSApp activateIgnoringOtherApps:YES];
 
@@ -286,6 +289,8 @@ destroy_window_data(SWindowData *window_data)
         [window removeWindowData];
         [window performClose:nil];
 
+        mfb_timer_destroy(window_data_osx->timer);
+
         memset(window_data_osx, 0, sizeof(SWindowData_OSX));
         free(window_data_osx);
     }
@@ -303,14 +308,12 @@ update_events(SWindowData *window_data)
     NSEvent* event;
 
     NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
-    do
+    do {
-    {
         event = [NSApp nextEventMatchingMask:NSEventMaskAny untilDate:[NSDate distantPast] inMode:NSDefaultRunLoopMode dequeue:YES];
         if (event) {
             [NSApp sendEvent:event];
         }
-    }
+    } while ((window_data->close == false) && event);
-    while ((window_data->close == false) && event);
 
     [pool release];
 }
@@ -375,6 +378,59 @@ mfb_update_events(struct mfb_window *window)
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
+extern double   g_time_for_frame;
+
+bool
+mfb_wait_sync(struct mfb_window *window) 
+{
+    NSEvent* event;
+
+    if(window == 0x0) {
+        return STATE_INVALID_WINDOW;
+    }
+
+    SWindowData *window_data = (SWindowData *) window;
+    if(window_data->close) {
+        destroy_window_data(window_data);
+        return false;
+    }
+
+    //NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
+
+    SWindowData_OSX *window_data_osx = (SWindowData_OSX *) window_data->specific;
+    double      current;
+    uint32_t    millis = 1;
+    while(1) {
+        event = [NSApp nextEventMatchingMask:NSEventMaskAny untilDate:[NSDate distantPast] inMode:NSDefaultRunLoopMode dequeue:YES];
+        if (event) {
+            [NSApp sendEvent:event];
+        }
+        
+        if(window_data->close) {
+            destroy_window_data(window_data);
+            return false;
+        }
+
+        current = mfb_timer_now(window_data_osx->timer);
+        if (current >= g_time_for_frame) {
+            mfb_timer_reset(window_data_osx->timer);
+            return true;
+        }
+        else if(current >= g_time_for_frame * 0.8) {
+            millis = 0;
+        }
+        
+        usleep(millis * 1000);
+        //sched_yield();
+    }
+
+    //[pool release];
+
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
 bool 
 mfb_set_viewport(struct mfb_window *window, unsigned offset_x, unsigned offset_y, unsigned width, unsigned height) 
 {
@@ -540,3 +596,35 @@ init_keycodes()
     g_keycodes[0x43] = KB_KEY_KP_MULTIPLY;
     g_keycodes[0x4E] = KB_KEY_KP_SUBTRACT;
 }
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+extern double   g_timer_frequency;
+extern double   g_timer_resolution;
+
+uint64_t 
+mfb_timer_tick() {
+    static mach_timebase_info_data_t    timebase = { 0 };
+
+    if (timebase.denom == 0) {
+        (void) mach_timebase_info(&timebase);
+    }
+    
+    uint64_t time = mach_absolute_time();
+
+    //return (time * s_timebase_info.numer) / s_timebase_info.denom;
+
+    // Perform the arithmetic at 128-bit precision to avoid the overflow!
+    uint64_t high    = (time >> 32) * timebase.numer;
+    uint64_t highRem = ((high % timebase.denom) << 32) / timebase.denom;
+    uint64_t low     = (time & 0xFFFFFFFFull) * timebase.numer / timebase.denom;
+    high /= timebase.denom;
+    
+    return (high << 32) + highRem + low;
+}
+
+void 
+mfb_timer_init() {
+    g_timer_frequency  = 1e+9;
+    g_timer_resolution = 1.0 / g_timer_frequency;
+}

src/macosx/WindowData_OSX.h

@@ -10,7 +10,9 @@
 @class OSXWindow;
 
 typedef struct {
-    OSXWindow   *window;
+    OSXWindow           *window;
+    struct mfb_timer    *timer;
+    
 #if defined(USE_METAL_API)
         struct {
             id<MTLCommandQueue>         command_queue;

src/wayland/WaylandMiniFB.c

@@ -27,6 +27,7 @@ destroy_window_data(SWindowData *window_data)
 
     SWindowData_Way   *window_data_way = (SWindowData_Way *) window_data->specific;
     if(window_data_way != 0x0) {
+        mfb_timer_destroy(window_data_way->timer);
         memset(window_data_way, 0, sizeof(SWindowData_Way));
         free(window_data_way);
     }
@@ -596,8 +597,8 @@ mfb_open(const char *title, unsigned width, unsigned height)
 
     init_keycodes();
 
-    if (wl_display_dispatch(window_data_way->display) == -1 || wl_display_roundtrip(window_data_way->display) == -1)
+    if (wl_display_dispatch(window_data_way->display) == -1 || 
-    {
+        wl_display_roundtrip(window_data_way->display) == -1) {
         return 0x0;
     }
 
@@ -667,6 +668,8 @@ mfb_open(const char *title, unsigned width, unsigned height)
     wl_surface_damage(window_data_way->surface, window_data->dst_offset_x, window_data->dst_offset_y, window_data->dst_width, window_data->dst_height);
     wl_surface_commit(window_data_way->surface);
 
+    window_data_way->timer = mfb_timer_create();
+
     mfb_set_keyboard_callback((struct mfb_window *) window_data, keyboard_default);
 
     printf("Window created using Wayland API\n");
@@ -762,7 +765,7 @@ mfb_update_events(struct mfb_window *window)
     if (!window_data_way->display || wl_display_get_error(window_data_way->display) != 0)
         return STATE_INTERNAL_ERROR;
 
-    if (wl_display_dispatch(window_data_way->display) == -1 || wl_display_roundtrip(window_data_way->display) == -1) {
+    if (wl_display_dispatch_pending(window_data_way->display) == -1) {
         return STATE_INTERNAL_ERROR;
     }
 
@@ -771,6 +774,51 @@ mfb_update_events(struct mfb_window *window)
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
+extern double   g_time_for_frame;
+
+bool 
+mfb_wait_sync(struct mfb_window *window) {
+    if(window == 0x0) {
+        return false;
+    }
+
+    SWindowData *window_data = (SWindowData *) window;
+    if(window_data->close) {
+        destroy(window_data);
+        return false;
+    }
+
+    SWindowData_Way   *window_data_way = (SWindowData_Way *) window_data->specific;
+    double      current;
+    uint32_t    millis = 1;
+    while(1) {
+        if (wl_display_dispatch_pending(window_data_way->display) == -1) {
+            return false;
+        }
+        
+        if(window_data->close) {
+            destroy_window_data(window_data);
+            return false;
+        }
+
+        current = mfb_timer_now(window_data_way->timer);
+        if (current >= g_time_for_frame) {
+            mfb_timer_reset(window_data_way->timer);
+            return true;
+        }
+        else if(current >= g_time_for_frame * 0.8) {
+            millis = 0;
+        }
+
+        usleep(millis * 1000);
+        //sched_yield();
+    }
+
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
 extern short int g_keycodes[512];
 
 void 

src/wayland/WindowData_Way.h

@@ -53,5 +53,6 @@ typedef struct
     uint32_t                buffer_stride;
 
     uint32_t                mod_keys;
+    struct mfb_timer        *timer;
     bool                    close;
 } SWindowData_Way;

src/windows/WinMiniFB.c

@@ -48,10 +48,8 @@ WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) {
 
                 StretchDIBits(window_data_win->hdc, window_data->dst_offset_x, window_data->dst_offset_y, window_data->dst_width, window_data->dst_height, 0, 0, window_data->buffer_width, window_data->buffer_height, window_data->draw_buffer, 
                               window_data_win->bitmapInfo, DIB_RGB_COLORS, SRCCOPY);
-
-                ValidateRect(hWnd, 0x0);
             }
-
+            ValidateRect(hWnd, 0x0);
             break;
         }
 
@@ -359,6 +357,8 @@ mfb_open_ex(const char *title, unsigned width, unsigned height, unsigned flags)
 
     window_data_win->hdc = GetDC(window_data_win->window);
 
+    window_data_win->timer = mfb_timer_create();
+
     mfb_set_keyboard_callback((struct mfb_window *) window_data, keyboard_default);
 
     return (struct mfb_window *) window_data;
@@ -421,9 +421,8 @@ mfb_update_events(struct mfb_window *window) {
 
     SWindowData_Win *window_data_win = (SWindowData_Win *) window_data->specific;
     while (window_data->close == false && PeekMessage(&msg, window_data_win->window, 0, 0, PM_REMOVE)) {
-        if(msg.message == WM_PAINT)
+        //if(msg.message == WM_PAINT)
-            return STATE_OK;
+        //    return STATE_OK;
-
         TranslateMessage(&msg);
         DispatchMessage(&msg);
     }
@@ -433,6 +432,53 @@ mfb_update_events(struct mfb_window *window) {
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
+extern double   g_time_for_frame;
+
+bool
+mfb_wait_sync(struct mfb_window *window) {
+    MSG msg;
+    
+    if (window == 0x0) {
+        return false;
+    }
+
+    SWindowData *window_data = (SWindowData *)window;
+    if (window_data->close) {
+        destroy_window_data(window_data);
+        return false;
+    }
+
+    SWindowData_Win *window_data_win = (SWindowData_Win *) window_data->specific;
+    double      current;
+    uint32_t    millis = 1;
+    while (1) {
+        if(PeekMessage(&msg, window_data_win->window, 0, 0, PM_REMOVE)) {
+            TranslateMessage(&msg);
+            DispatchMessage(&msg);
+        }
+
+        if (window_data->close) {
+            destroy_window_data(window_data);
+            return false;
+        }
+
+        current = mfb_timer_now(window_data_win->timer);;
+        if (current >= g_time_for_frame) {
+            mfb_timer_reset(window_data_win->timer);
+            return true;
+        }
+        else if(current >= g_time_for_frame * 0.8) {
+            millis = 0;
+        }
+
+        Sleep(millis);
+    }
+
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
 void 
 destroy_window_data(SWindowData *window_data) {
     if (window_data == 0x0)
@@ -453,6 +499,8 @@ destroy_window_data(SWindowData *window_data) {
     window_data_win->window = 0;
     window_data_win->hdc = 0;
     window_data_win->bitmapInfo = 0x0;
+    mfb_timer_destroy(window_data_win->timer);
+    window_data_win->timer = 0x0;
     window_data->close = true;
 }
 
@@ -659,3 +707,27 @@ mfb_set_viewport(struct mfb_window *window, unsigned offset_x, unsigned offset_y
 
     return true;
 }
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+extern double   g_timer_frequency;
+extern double   g_timer_resolution;
+
+uint64_t 
+mfb_timer_tick() {
+    int64_t     counter;
+
+    QueryPerformanceCounter((LARGE_INTEGER *) &counter);
+
+    return counter;
+}
+
+void 
+mfb_timer_init() {
+    uint64_t    frequency;
+
+    QueryPerformanceFrequency((LARGE_INTEGER *) &frequency);
+
+    g_timer_frequency  = (double) ((int64_t) frequency);
+    g_timer_resolution = 1.0 / g_timer_frequency;
+}

src/windows/WindowData_Win.h

@@ -7,9 +7,10 @@
 
 
 typedef struct {
-    HWND        window;
+    HWND                window;
-    WNDCLASS    wc;
+    WNDCLASS            wc;
-    HDC         hdc;
+    HDC                 hdc;
-    BITMAPINFO  *bitmapInfo;
+    BITMAPINFO          *bitmapInfo;
-    bool        mouse_inside;
+    struct mfb_timer    *timer;
+    bool                mouse_inside;
 } SWindowData_Win;

src/x11/WindowData_X11.h

@@ -6,15 +6,16 @@
 
 
 typedef struct {
-    Window      window;
+    Window              window;
-
+        
-    Display     *display;
+    Display             *display;
-    int         screen;
+    int                 screen;
-    GC          gc;
+    GC                  gc;
-    XImage      *image;
+    XImage              *image;
-
+        
-    void        *image_buffer;
+    void                *image_buffer;
-    XImage      *image_scaler;
+    XImage              *image_scaler;
-    uint32_t    image_scaler_width;
+    uint32_t            image_scaler_width;
-    uint32_t    image_scaler_height;
+    uint32_t            image_scaler_height;
+    struct mfb_timer   *timer;
 } SWindowData_X11;

src/x11/X11MiniFB.c

@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <MiniFB.h>
 #include <MiniFB_internal.h>
 #include "WindowData.h"
@@ -185,6 +186,8 @@ mfb_open_ex(const char *title, unsigned width, unsigned height, unsigned flags)
 
     window_data_x11->image = XCreateImage(window_data_x11->display, CopyFromParent, depth, ZPixmap, 0, 0x0, width, height, 32, width * 4);
 
+    window_data_x11->timer = mfb_timer_create();
+
     mfb_set_keyboard_callback((struct mfb_window *) window_data, keyboard_default);
 
     printf("Window created using X11 API\n");
@@ -203,106 +206,111 @@ int translate_key(int scancode);
 int translate_mod(int state);
 int translate_mod_ex(int key, int state, int is_pressed);
 
+static void 
+processEvent(SWindowData *window_data, XEvent *event) {
+    switch (event->type) {
+        case KeyPress:
+        case KeyRelease: 
+        {
+            mfb_key key_code      = (mfb_key) translate_key(event->xkey.keycode);
+            int is_pressed        = (event->type == KeyPress);
+            window_data->mod_keys = translate_mod_ex(key_code, event->xkey.state, is_pressed);
+
+            window_data->key_status[key_code] = is_pressed;
+            kCall(keyboard_func, key_code, (mfb_key_mod) window_data->mod_keys, is_pressed);
+        }
+        break;
+
+        case ButtonPress:
+        case ButtonRelease:
+        {
+            mfb_mouse_button button = (mfb_mouse_button) event->xbutton.button;
+            int          is_pressed = (event->type == ButtonPress);
+            window_data->mod_keys   = translate_mod(event->xkey.state);
+            switch (button) {
+                case Button1:
+                case Button2:
+                case Button3:
+                    kCall(mouse_btn_func, button, (mfb_key_mod) window_data->mod_keys, is_pressed);
+                    break;
+
+                case Button4:
+                    kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, 0.0f, 1.0f);
+                    break;
+                case Button5:
+                    kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, 0.0f, -1.0f);
+                    break;
+
+                case 6:
+                    kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, 1.0f, 0.0f);
+                    break;
+                case 7:
+                    kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, -1.0f, 0.0f);
+                    break;
+
+                default:
+                    kCall(mouse_btn_func, (mfb_mouse_button) (button - 4), (mfb_key_mod) window_data->mod_keys, is_pressed);
+                    break;
+            }
+        }
+        break;
+
+        case MotionNotify:
+            window_data->mouse_pos_x = event->xmotion.x;
+            window_data->mouse_pos_y = event->xmotion.y;
+            kCall(mouse_move_func, event->xmotion.x, event->xmotion.y);
+            break;
+
+        case ConfigureNotify: 
+        {
+            window_data->window_width  = event->xconfigure.width;
+            window_data->window_height = event->xconfigure.height;
+            window_data->dst_offset_x = 0;
+            window_data->dst_offset_y = 0;
+            window_data->dst_width    = window_data->window_width;
+            window_data->dst_height   = window_data->window_height;
+
+            SWindowData_X11 *window_data_x11 = (SWindowData_X11 *) window_data->specific;
+            XClearWindow(window_data_x11->display, window_data_x11->window);
+            kCall(resize_func, window_data->window_width, window_data->window_height);
+        }
+        break;
+
+        case EnterNotify:
+        case LeaveNotify:
+        break;
+
+        case FocusIn:
+            window_data->is_active = true;
+            kCall(active_func, true);
+            break;
+
+        case FocusOut:
+            window_data->is_active = false;
+            kCall(active_func, false);
+            break;
+
+        case DestroyNotify:
+            window_data->close = true;
+            return;
+            break;
+    }
+}
+
 static void 
 processEvents(SWindowData *window_data) {
     XEvent          event;
-    SWindowData_X11   *window_data_x11 = (SWindowData_X11 *) window_data->specific;
+    SWindowData_X11 *window_data_x11 = (SWindowData_X11 *) window_data->specific;
 
     while ((window_data->close == false) && XPending(window_data_x11->display)) {
         XNextEvent(window_data_x11->display, &event);
-
+        processEvent(window_data, &event);
-        switch (event.type) {
-            case KeyPress:
-            case KeyRelease: 
-            {
-                mfb_key key_code      = (mfb_key) translate_key(event.xkey.keycode);
-                int is_pressed        = (event.type == KeyPress);
-                window_data->mod_keys = translate_mod_ex(key_code, event.xkey.state, is_pressed);
-
-                window_data->key_status[key_code] = is_pressed;
-                kCall(keyboard_func, key_code, (mfb_key_mod) window_data->mod_keys, is_pressed);
-            }
-            break;
-
-            case ButtonPress:
-            case ButtonRelease:
-            {
-                mfb_mouse_button button = (mfb_mouse_button) event.xbutton.button;
-                int          is_pressed = (event.type == ButtonPress);
-                window_data->mod_keys   = translate_mod(event.xkey.state);
-                switch (button) {
-                    case Button1:
-                    case Button2:
-                    case Button3:
-                        kCall(mouse_btn_func, button, (mfb_key_mod) window_data->mod_keys, is_pressed);
-                        break;
-
-                    case Button4:
-                        kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, 0.0f, 1.0f);
-                        break;
-                    case Button5:
-                        kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, 0.0f, -1.0f);
-                        break;
-
-                    case 6:
-                        kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, 1.0f, 0.0f);
-                        break;
-                    case 7:
-                        kCall(mouse_wheel_func, (mfb_key_mod) window_data->mod_keys, -1.0f, 0.0f);
-                        break;
-
-                    default:
-                        kCall(mouse_btn_func, (mfb_mouse_button) (button - 4), (mfb_key_mod) window_data->mod_keys, is_pressed);
-                        break;
-                }
-            }
-            break;
-
-            case MotionNotify:
-                window_data->mouse_pos_x = event.xmotion.x;
-                window_data->mouse_pos_y = event.xmotion.y;
-                kCall(mouse_move_func, event.xmotion.x, event.xmotion.y);
-                break;
-
-            case ConfigureNotify: 
-            {
-                window_data->window_width  = event.xconfigure.width;
-                window_data->window_height = event.xconfigure.height;
-                window_data->dst_offset_x = 0;
-                window_data->dst_offset_y = 0;
-                window_data->dst_width    = window_data->window_width;
-                window_data->dst_height   = window_data->window_height;
-
-                XClearWindow(window_data_x11->display, window_data_x11->window);
-                kCall(resize_func, window_data->window_width, window_data->window_height);
-            }
-            break;
-
-            case EnterNotify:
-            case LeaveNotify:
-            break;
-
-            case FocusIn:
-                window_data->is_active = true;
-                kCall(active_func, true);
-                break;
-
-            case FocusOut:
-                window_data->is_active = false;
-                kCall(active_func, false);
-                break;
-
-            case DestroyNotify:
-                window_data->close = true;
-                return;
-                break;
-        }
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
-void destroy(SWindowData *window_data);
+void destroy_window_data(SWindowData *window_data);
 
 mfb_update_state 
 mfb_update(struct mfb_window *window, void *buffer) {
@@ -312,7 +320,7 @@ mfb_update(struct mfb_window *window, void *buffer) {
 
     SWindowData *window_data = (SWindowData *) window;
     if (window_data->close) {
-        destroy(window_data);
+        destroy_window_data(window_data);
         return STATE_EXIT;
     }
 
@@ -368,7 +376,7 @@ mfb_update_events(struct mfb_window *window) {
 
     SWindowData *window_data = (SWindowData *) window;
     if (window_data->close) {
-        destroy(window_data);
+        destroy_window_data(window_data);
         return STATE_EXIT;
     }
 
@@ -381,8 +389,56 @@ mfb_update_events(struct mfb_window *window) {
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
+extern double   g_time_for_frame;
+
+bool 
+mfb_wait_sync(struct mfb_window *window) {
+    if (window == 0x0) {
+        return STATE_INVALID_WINDOW;
+    }
+
+    SWindowData *window_data = (SWindowData *) window;
+    if (window_data->close) {
+        destroy_window_data(window_data);
+        return false;
+    }
+
+    SWindowData_X11 *window_data_x11 = (SWindowData_X11 *) window_data->specific;
+    XFlush(window_data_x11->display);
+    XEvent      event;
+    double      current;
+    uint32_t    millis = 1;
+    while(1) {
+        if(XEventsQueued(window_data_x11->display, QueuedAlready) > 0) {
+            XNextEvent(window_data_x11->display, &event);
+            processEvent(window_data, &event);
+        }
+        
+        if(window_data->close) {
+            destroy_window_data(window_data);
+            return false;
+        }
+
+        current = mfb_timer_now(window_data_x11->timer);
+        if (current >= g_time_for_frame) {
+            mfb_timer_reset(window_data_x11->timer);
+            return true;
+        }
+        else if(current >= g_time_for_frame * 0.8) {
+            millis = 0;
+        }
+
+        usleep(millis * 1000);
+        //sched_yield();
+    }
+    
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
 void 
-destroy(SWindowData *window_data)  {
+destroy_window_data(SWindowData *window_data)  {
     if (window_data != 0x0) {
         if (window_data->specific != 0x0) {
             SWindowData_X11   *window_data_x11 = (SWindowData_X11 *) window_data->specific;
@@ -392,6 +448,7 @@ destroy(SWindowData *window_data)  {
                 XDestroyWindow(window_data_x11->display, window_data_x11->window);
                 XCloseDisplay(window_data_x11->display);
             }
+            mfb_timer_destroy(window_data_x11->timer);
             memset(window_data_x11, 0, sizeof(SWindowData_X11));
             free(window_data_x11);
         }

tests/input_events.c

@@ -114,8 +114,7 @@ main()
 
     mfb_set_user_data(window, (void *) "Input Events Test");
 
-    for (;;)
+    do {
-    {
         int              i;
         mfb_update_state state;
 
@@ -143,7 +142,7 @@ main()
             window = 0x0;
             break;
         }
-    }
+    } while(mfb_wait_sync(window));
 
     return 0;
 }

tests/input_events_cpp.cpp

@@ -110,13 +110,11 @@ main()
 
     mfb_set_user_data(window, (void *) "Input Events CPP Test");
 
-    for (;;)
+    do {
-    {
         int         i;
         mfb_update_state state;
 
-        for (i = 0; i < WIDTH * HEIGHT; ++i)
+        for (i = 0; i < WIDTH * HEIGHT; ++i) {
-        {
             noise = seed;
             noise >>= 3;
             noise ^= seed;
@@ -133,7 +131,7 @@ main()
             window = 0x0;
             break;
         }
-    }
+    } while(mfb_wait_sync(window));
 
     return 0;
 }

tests/multiple_windows.c

@@ -138,6 +138,8 @@ main()
         pallete[64*7 + c] = MFB_RGB(255-col, 0,       0);
     }
 
+    mfb_set_target_fps(10);
+
     //--
     float   time = 0;
     for (;;)
@@ -191,6 +193,12 @@ main()
         if(window_a == 0x0 && window_b == 0x0) {
             break;
         }
+
+        // Don't need to do this for both windows in the same thread
+        if(window_a != 0x0)
+            mfb_wait_sync(window_a);
+        else if(window_b != 0x0)
+            mfb_wait_sync(window_b);
     }
 
     return 0;

tests/noise.c

@@ -17,13 +17,11 @@ main()
     if (!window)
         return 0;
 
-    for (;;)
+    do {
-    {
         int         i;
         mfb_update_state state;
 
-        for (i = 0; i < WIDTH * HEIGHT; ++i)
+        for (i = 0; i < WIDTH * HEIGHT; ++i) {
-        {
             noise = seed;
             noise >>= 3;
             noise ^= seed;
@@ -40,7 +38,7 @@ main()
             window = 0x0;
             break;
         }
-    }
+    } while(mfb_wait_sync(window));
 
     return 0;
 }