Updated "ugly" EGL wayland example to support XDG

init_window.c

// gcc -o test init_window.c -I. -lwayland-client -lwayland-server -lwayland-client-protocol -lwayland-egl -lEGL -lGLESv2
#include <wayland-client-core.h>
#include <wayland-client.h>
#include <wayland-server.h>
#include <wayland-client-protocol.h>
#include <wayland-egl.h> // Wayland EGL MUST be included before EGL headers

#include "xdg-shell-client-protocol.h"

#include "init_window.h"
#include "log.h"

#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#include <math.h>

#include <sys/time.h>

#include <GLES2/gl2.h>

struct wl_compositor *compositor = NULL;
struct wl_surface *surface;
struct wl_egl_window *egl_window;
struct wl_region *region;

struct xdg_wm_base *XDGWMBase;
struct xdg_surface *XDGSurface;
struct xdg_toplevel *XDGToplevel;

struct _escontext ESContext = {
	.native_display = NULL,
	.window_width = 0,
	.window_height = 0,
	.native_window  = 0,
	.display = NULL,
	.context = NULL,
	.surface = NULL
};

#define TRUE 1
#define FALSE 0

#define WINDOW_WIDTH 1280
#define WINDOW_HEIGHT 720

bool program_alive;
int32_t old_w, old_h;

static void xdg_toplevel_handle_configure(void *data,
		struct xdg_toplevel *xdg_toplevel, int32_t w, int32_t h,
		struct wl_array *states) {

	// no window geometry event, ignore
	if(w == 0 && h == 0) return;

	// window resized
	if(old_w != w && old_h != h) {
		old_w = w;
		old_h = h;

		wl_egl_window_resize(ESContext.native_window, w, h, 0, 0);
		wl_surface_commit(surface);
	}
}

static void xdg_toplevel_handle_close(void *data,
		struct xdg_toplevel *xdg_toplevel) {
	// window closed, be sure that this event gets processed
	program_alive = false;
}

struct xdg_toplevel_listener xdg_toplevel_listener = {
	.configure = xdg_toplevel_handle_configure,
	.close = xdg_toplevel_handle_close,
};


static void xdg_surface_configure(void *data, struct xdg_surface *xdg_surface,
		uint32_t serial) {
	// confirm that you exist to the compositor
	xdg_surface_ack_configure(xdg_surface, serial);

}

const struct xdg_surface_listener xdg_surface_listener = {
	.configure = xdg_surface_configure,
};

static void xdg_wm_base_ping(void *data, struct xdg_wm_base *xdg_wm_base,
		uint32_t serial) {
	xdg_wm_base_pong(xdg_wm_base, serial);
}

const struct xdg_wm_base_listener xdg_wm_base_listener = {
	.ping = xdg_wm_base_ping,
};

void CreateNativeWindow(char *title, int width, int height) {
	old_w = WINDOW_WIDTH;
	old_h = WINDOW_HEIGHT;

	region = wl_compositor_create_region(compositor);

	wl_region_add(region, 0, 0, width, height);
	wl_surface_set_opaque_region(surface, region);

	struct wl_egl_window *egl_window = 
		wl_egl_window_create(surface, width, height);

	if (egl_window == EGL_NO_SURFACE) {
		LOG("No window !?\n");
		exit(1);
	}
	else LOG("Window created !\n");
	ESContext.window_width = width;
	ESContext.window_height = height;
	ESContext.native_window = egl_window;

}

EGLBoolean CreateEGLContext ()
{
	EGLint numConfigs;
	EGLint majorVersion;
	EGLint minorVersion;
	EGLContext context;
	EGLSurface surface;
	EGLConfig config;
	EGLint fbAttribs[] =
	{
		EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
		EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
		EGL_RED_SIZE,        8,
		EGL_GREEN_SIZE,      8,
		EGL_BLUE_SIZE,       8,
		EGL_NONE
	};
	EGLint contextAttribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE, EGL_NONE };
	EGLDisplay display = eglGetDisplay( ESContext.native_display );
	if ( display == EGL_NO_DISPLAY )
	{
		LOG("No EGL Display...\n");
		return EGL_FALSE;
	}

	// Initialize EGL
	if ( !eglInitialize(display, &majorVersion, &minorVersion) )
	{
		LOG("No Initialisation...\n");
		return EGL_FALSE;
	}

	// Get configs
	if ( (eglGetConfigs(display, NULL, 0, &numConfigs) != EGL_TRUE) || (numConfigs == 0))
	{
		LOG("No configuration...\n");
		return EGL_FALSE;
	}

	// Choose config
	if ( (eglChooseConfig(display, fbAttribs, &config, 1, &numConfigs) != EGL_TRUE) || (numConfigs != 1))
	{
		LOG("No configuration...\n");
		return EGL_FALSE;
	}

	// Create a surface
	surface = eglCreateWindowSurface(display, config, ESContext.native_window, NULL);
	if ( surface == EGL_NO_SURFACE )
	{
		LOG("No surface...\n");
		return EGL_FALSE;
	}

	// Create a GL context
	context = eglCreateContext(display, config, EGL_NO_CONTEXT, contextAttribs );
	if ( context == EGL_NO_CONTEXT )
	{
		LOG("No context...\n");
		return EGL_FALSE;
	}

	// Make the context current
	if ( !eglMakeCurrent(display, surface, surface, context) )
	{
		LOG("Could not make the current window current !\n");
		return EGL_FALSE;
	}

	ESContext.display = display;
	ESContext.surface = surface;
	ESContext.context = context;
	return EGL_TRUE;
}

EGLBoolean CreateWindowWithEGLContext(char *title, int width, int height) {
	CreateNativeWindow(title, width, height);
	return CreateEGLContext();
}

void draw() {
	glClearColor(0.5, 0.3, 0.0, 1.0);

	//struct timeval tv;

	//gettimeofday(&tv, NULL);

	//float time = tv.tv_sec + tv.tv_usec/1000000.0;

	//static GLfloat vertex_data[] = {
	//	0.6, 0.6, 1.0,
	//	-0.6, -0.6, 1.0,
	//	0.0, 1.0, 1.0
	//};

	//for(int i=0; i<3; i++) {
	//	vertex_data[i*3+0] = vertex_data[i*3+0]*cos(time) - vertex_data[i*3+1]*sin(time); 
	//	vertex_data[i*3+1] = vertex_data[i*3+0]*sin(time) + vertex_data[i*3+1]*cos(time); 
	//}

	glClear(GL_COLOR_BUFFER_BIT);

	//glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, vertex_data);
	//glEnableVertexAttribArray(0);

	//glDrawArrays(GL_TRIANGLES, 0, 3);
}

unsigned long last_click = 0;
void RefreshWindow() { eglSwapBuffers(ESContext.display, ESContext.surface); }

static void global_registry_handler
(void *data, struct wl_registry *registry, uint32_t id,
 const char *interface, uint32_t version) {
	LOG("Got a registry event for %s id %d\n", interface, id);
	if (strcmp(interface, "wl_compositor") == 0)
		compositor = 
			wl_registry_bind(registry, id, &wl_compositor_interface, 1);
	else if(strcmp(interface, xdg_wm_base_interface.name) == 0) {
		XDGWMBase = wl_registry_bind(registry, id,
				&xdg_wm_base_interface, 1);
		xdg_wm_base_add_listener(XDGWMBase, &xdg_wm_base_listener, NULL);
	} 
}

static void global_registry_remover
(void *data, struct wl_registry *registry, uint32_t id) {
	LOG("Got a registry losing event for %d\n", id);
}

const struct wl_registry_listener listener = {
	global_registry_handler,
	global_registry_remover
};

static void
get_server_references() {

	struct wl_display * display = wl_display_connect(NULL);
	if (display == NULL) {
		LOG("Can't connect to wayland display !?\n");
		exit(1);
	}
	LOG("Got a display !");

	struct wl_registry *wl_registry =
		wl_display_get_registry(display);
	wl_registry_add_listener(wl_registry, &listener, NULL);

	// This call the attached listener global_registry_handler
	wl_display_dispatch(display);
	wl_display_roundtrip(display);

	// If at this point, global_registry_handler didn't set the 
	// compositor, nor the shell, bailout !
	if (compositor == NULL || XDGWMBase == NULL) {
		LOG("No compositor !? No XDG !! There's NOTHING in here !\n");
		exit(1);
	}
	else {
		LOG("Okay, we got a compositor and a shell... That's something !\n");
		ESContext.native_display = display;
	}
}

void destroy_window() {
	eglDestroySurface(ESContext.display, ESContext.surface);
	wl_egl_window_destroy(ESContext.native_window);
	xdg_toplevel_destroy(XDGToplevel);
	xdg_surface_destroy(XDGSurface);
	wl_surface_destroy(surface);
	eglDestroyContext(ESContext.display, ESContext.context);
}

int main() {
	get_server_references();

	surface = wl_compositor_create_surface(compositor);
	if (surface == NULL) {
		LOG("No Compositor surface ! Yay....\n");
		exit(1);
	}
	else LOG("Got a compositor surface !\n");

	XDGSurface = xdg_wm_base_get_xdg_surface(XDGWMBase, surface);

	xdg_surface_add_listener(XDGSurface, &xdg_surface_listener, NULL);

	XDGToplevel = xdg_surface_get_toplevel(XDGSurface);
	xdg_toplevel_set_title(XDGToplevel, "Wayland EGL example");
	xdg_toplevel_add_listener(XDGToplevel, &xdg_toplevel_listener, NULL);

	wl_surface_commit(surface);

	CreateWindowWithEGLContext("Nya", 1280, 720);

	program_alive = true;

	while (program_alive) {
		wl_display_dispatch_pending(ESContext.native_display);
		draw();
		RefreshWindow();
	}

	destroy_window();
	wl_display_disconnect(ESContext.native_display);
	LOG("Display disconnected !\n");

	exit(0);
}

Hi, i'm getting a "EGL_BAD_ALLOC" error when try to do eglCreateWindowSurface call. Do you happen to know why is that happening?

Thanks.

Hi, i'm getting a "EGL_BAD_ALLOC" error when try to do eglCreateWindowSurface call. Do you happen to know why is that happening?

Thanks.

Check if the target EGL version is supported on your machine. (You have eglgears for that)

Hi, i'm able to resolve it,
i had to bind render api after eglInitialize call to fix this issue, i did it like this

 EGLint major;
 EGLint minor;
 result = eglInitialize(display, &major, &minor);

 if( result != EGL_TRUE )
 {
        printf("Failed to Initialize EGL\n");
 }
 result = eglBindAPI(EGL_OPENGL_ES_API);
 if( result != EGL_TRUE )
 {
     printf("Failed to bind API\n");
 }