minifb-zig-port/README.md

# 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:

```c
struct mfb_window *window = mfb_open_ex("my display", 800, 600, WF_RESIZABLE);
if (!window)
	return 0;

for (;;)
{
	int state;

	// TODO: add some fancy rendering to the buffer of size 800 * 600

	state = mfb_update(buffer);

	if (state < 0)
		break;
}
```


Furthermore, you can _add callbacks to the windows_:

```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_:

```c
mfb_set_user_data(window, (void *) myData);
...
myData = (someCast *) mfb_get_user_data(window);
```


Finally, you can _get information about the events in the window directly_:

```c
bool                mfb_is_window_active(struct mfb_window *window);

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.


**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

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)

MacOS X Mojave does not support Cocoa framework as expected. For that reason now you can switch to Metal API.
To enable it just compile defining the preprocessor macro USE_METAL_API.

If you use CMake just enable the flag:

```
mkdir build
cd build
cmake .. -DUSE_METAL_API=ON
```

or if you don't want to use Metal API:

```
mkdir build
cd build
cmake .. -DUSE_METAL_API=OFF
```


### iOS (beta)

It works with and without an UIWindow created. 
If you want to create the UIWindow through an Story Board, remember to set the UIViewController as iOSViewController and the UIView as iOSView.

**Issues:**

- It seems that you have to manually set 'tvOS Deployment Target' to less than 13.
- It seems that you have to manually set 'Launch Screen File' in project > executable > general to be able to get the real device height.
- You need to manually set the 'Signing Team' and 'Bundle Identifier'. 
- No multitouch is available yet.
- As this version uses Metal API it cannot be run in the emulator.

**Functions:**

Some of the MiniFB functions don't make sense on mobile. 
The available functions for iOS are:
```c
struct mfb_window * mfb_open(const char *title, unsigned width, unsigned height);
struct mfb_window * mfb_open_ex(const char *title, unsigned width, unsigned height, unsigned flags);	// flags ignored

mfb_update_state    mfb_update(struct mfb_window *window, void *buffer);

void                mfb_close(struct mfb_window *window);

void                mfb_set_user_data(struct mfb_window *window, void *user_data);
void *              mfb_get_user_data(struct mfb_window *window);

bool                mfb_set_viewport(struct mfb_window *window, unsigned offset_x, unsigned offset_y, unsigned width, unsigned height);

void                mfb_set_mouse_button_callback(struct mfb_window *window, mfb_mouse_button_func callback);
void                mfb_set_mouse_move_callback(struct mfb_window *window, mfb_mouse_move_func callback);
void                mfb_set_resize_callback(struct mfb_window *window, mfb_resize_func callback);

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
```

Timers are also available.
```c
struct mfb_timer *  mfb_timer_create(void);
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(void);
double              mfb_timer_get_resolution(void);
```

For now, no multitouch is available.

**Example:**

```objective-c
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    if(g_window == 0x0) {
        g_width  = [UIScreen mainScreen].bounds.size.width;
        g_height = [UIScreen mainScreen].bounds.size.height;
        g_window = mfb_open("noise", g_width, g_height);
        if(g_window != 0x0) {
            g_buffer = malloc(g_width * g_height * 4);
        }
    }

    return YES;
}

- (void)applicationDidBecomeActive:(UIApplication *)application {    
    mDisplayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(OnUpdateFrame)];
    [mDisplayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
}

- (void)applicationWillTerminate:(UIApplication *)application {
    [mDisplayLink invalidate];
    mfb_close(g_window);
}

- (void) OnUpdateFrame {
    if(g_buffer != 0x0) {
		// Do your wonderful rendering stuff
    }
    
    mfb_update_state state = mfb_update(g_window, g_buffer);
    if (state != STATE_OK) {
        free(g_buffer);
        g_buffer = 0x0;
        g_width   = 0;
        g_height  = 0;
    }
}
```

**CMake**
```
mkdir build
cd build
cmake -G Xcode -DCMAKE_SYSTEM_NAME=iOS -DCMAKE_OSX_DEPLOYMENT_TARGET=11.0 ..
```


### 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)

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
cmake .. -DUSE_WAYLAND_API=OFF
```


### 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
cmake .. -DUSE_WAYLAND_API=ON
```