Peek

peek.cpp

#include <iostream>
#include <cassert>

#include <gtk/gtk.h>
#include <gdk/gdkscreen.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
#include <cairo.h>

static GtkWidget *window;
static GdkPixbufAnimation *pixbuf_animation;
static GdkPixbufAnimationIter* animationIter;

static gboolean draw(GtkWidget */*window*/, cairo_t* cr, gpointer /*user_data*/)
{
    static uint gindex = 0;
    static int fps_counter = 0;

    auto pixbuf = gdk_pixbuf_animation_iter_get_pixbuf(animationIter);
    gdk_cairo_set_source_pixbuf(cr, pixbuf, 0, 0);
    cairo_paint(cr);

    return false;
}

static void make_transparent(GtkWidget *widget)
{
    GdkScreen *screen = gtk_widget_get_screen(widget);
    GdkVisual *visual = gdk_screen_get_rgba_visual(screen);

    if (visual == nullptr)
    {
        visual = gdk_screen_get_system_visual(screen);
    }

    gtk_widget_set_visual(widget, visual);
}

static gboolean timer(gpointer /*user_data*/)
{
    GTimeVal time;
    g_get_current_time(&time);
    gdk_pixbuf_animation_iter_advance(animationIter, &time);
    g_timeout_add(gdk_pixbuf_animation_iter_get_delay_time(animationIter), timer, nullptr);
    gtk_widget_queue_draw(window);

    return FALSE;
}

int main(int ac, char** av)
{
    if ( fork() )
    {
        exit(0); // It's in your heeead, in your heeeead... :D
    }

    gtk_init(&ac, &av);

    window = gtk_window_new(GTK_WINDOW_POPUP);

    pixbuf_animation = gdk_pixbuf_animation_new_from_file("peek", nullptr);
    if (!pixbuf_animation)
    {
        exit(0);
    }

    GTimeVal time;
    g_get_current_time(&time);
    animationIter = gdk_pixbuf_animation_get_iter(pixbuf_animation, &time);
    timer(nullptr);

    gtk_window_set_title(GTK_WINDOW(window), "Never Gonna Give You Up!");
    gtk_window_set_decorated(GTK_WINDOW(window), false);
    gtk_widget_set_app_paintable(window, true);
    gtk_window_set_skip_taskbar_hint(GTK_WINDOW(window), true);
    gtk_window_set_skip_pager_hint(GTK_WINDOW(window), true);

    GdkRectangle workarea = {0};
    gdk_monitor_get_workarea(gdk_display_get_primary_monitor(gdk_display_get_default()), &workarea);

    auto imgw = gdk_pixbuf_animation_get_width (pixbuf_animation);
    auto imgh = gdk_pixbuf_animation_get_height (pixbuf_animation);
    gtk_window_resize(GTK_WINDOW(window), imgw, imgh);

    gtk_window_move(GTK_WINDOW(window), workarea.width - imgw, workarea.height - imgh / 2 - 50);

    make_transparent(window);

    g_signal_connect(G_OBJECT(window), "delete-event", gtk_main_quit, nullptr);
    g_signal_connect(G_OBJECT(window), "draw", G_CALLBACK(draw), nullptr);

    gtk_widget_show_all(window);

    gtk_main();

    return 0;
}