Slideshow demo to show Clutter + GStreamer exporting (compile with valac -g --save-temps --pkg gdk-pixbuf-2.0 --pkg gstreamer-0.10 --pkg gstreamer-app-0.10 --pkg gio-2.0 --pkg clutter-1.0 slideshow.vala)

slideshow.vala

using Clutter;
using Mx;

class ClutterDemo {

    private Stage stage;
    private Rectangle[] rectangles;
    private List<string> filenames;
    private int current;
    private Queue<string> queue;
    private uint timeout_id;
    
    private Texture image;
    
    private DeformTexture widget;

    const int TRANSITION = 2000;
    const int TIME = 3;
    
    public void add_filename(string filename) {
        var file = File.new_for_path(filename);
        if (file.query_file_type(FileQueryInfoFlags.NONE) == FileType.DIRECTORY) {
            var enumerator = file.enumerate_children (FILE_ATTRIBUTE_STANDARD_NAME, 0);
            var file_info = enumerator.next_file();
            while (file_info != null) {
                this.add_filename(GLib.Path.build_filename(filename, file_info.get_name()));
                file_info = enumerator.next_file();
            }
        } else {
            stdout.printf ("Adding: %s\n", filename);
            this.filenames.prepend(filename);
        }
    }

    public ClutterDemo (string[] filenames) {
    
        this.filenames = new List<string>();
        foreach (string filename in filenames) {
            this.add_filename(filename);
        }
        this.filenames.reverse();
        
        this.queue = new Queue<string>();
        this.fill_queue();
    
        this.current = -1;
        this.image = null;

        stage = (Stage) Stage.get_default ();
        stage.hide.connect (Clutter.main_quit);

        this.load_next();
        
        this.timeout_id = Timeout.add_seconds(TIME, this.load_next_timeout);
        
        stage.key_press_event.connect((actor, event) => {
            Source.remove(timeout_id);
            
            if (event.keyval == 65363)
                this.load_next(false);
            
            if (event.unicode_value.tolower() == 'q')
                Clutter.main_quit();
                
            this.timeout_id = Timeout.add_seconds(TIME, this.load_next_timeout);
            
            return false;
        });

        stage.color = Color () { alpha = 255 };
        stage.show_all ();
        
        Idle.add(() => {
            setup_video();
            return false;
        });
    }
    
    public void setup_video() {
        var timer = new Timer();

        int width = (int)this.stage.width;
        int height = (int)this.stage.height;

        var pipeline_desc = @"appsrc name=mysource ! videoparse width=$width height=$height format=rgb ! ffmpegcolorspace ! videoscale method=1 ! videorate ! theoraenc ! oggmux ! filesink location=video.ogv";

        var pipeline = (Gst.Pipeline) Gst.parse_launch(pipeline_desc);

        var bus = pipeline.get_bus();
        
        var app_src = (Gst.AppSrc) pipeline.get_by_name("mysource");
        
        ulong need_data_id = 0;
        
        app_src.need_data.connect(() => {
            //need_data_id = Idle.add(() => {
                var ms = timer.elapsed();
                debug("Giving data! elapsed %f, %dx%d", ms, width, height);
                
                var buffer = new Gst.Buffer();

                uint8[] data = this.stage.read_pixels(0, 0, (int) this.stage.width, (int) this.stage.height);
                debug("Has pixels!");
                data.length = (width * height * 4);
                
                var pixbuf = new Gdk.Pixbuf.from_data(data, Gdk.Colorspace.RGB, true, 8, width, height, width * 4, null);
                pixbuf.save("video%u.png".printf(Random.next_int()), "png");
                
                buffer.data = data;
                
                app_src.push_buffer(buffer);
                
                timer.start();
        });

        /* set the caps on the source */
        var caps = new Gst.Caps.simple("video/x-raw-rgb",
            "bpp", typeof(int), 32,
            "depth", typeof(int), 24,
            "width", typeof(int), width,
            "height", typeof(int), height
        );
        app_src.caps = caps;
        
        debug("Playing");
        pipeline.set_state(Gst.State.PLAYING);
    }
    
    public bool fill_queue() {
        this.queue.clear();
        foreach (string filename in this.filenames) {
            this.queue.push_head(filename);
        }
        return (queue.get_length() > 0);
    }
    
    public bool load_next_timeout() {
        return this.load_next(true);
    }
    
    public bool load_next(bool transition = false) {
        var previous = this.image;
        var previous_widget = this.widget;
        if (previous != null) {
            if (transition)
                previous.animate(AnimationMode.LINEAR, TRANSITION, opacity: 0).completed.connect(() => {
                    stage.remove_actor(previous);
                });
            else
                stage.remove_actor(previous);
        }
        
        Texture? image = null;
        while (image == null) {
            if (this.queue.is_empty() && !this.fill_queue())
                break;
            
            var filename = this.queue.pop_nth(Random.int_range(0, (int32)this.queue.get_length()));
            stdout.printf("Queue: %u\n", this.queue.get_length());
            try {
                image = new Texture();
                image.set_from_file(filename);
            } catch {
                image = null;
                stdout.printf("File %s is not a valid image\n", filename);
            }
        }
        
        if (image == null) {
            var text = new Text.full ("Bitstream Vera Sans 18",
                                      "No valid images found!",
                                      Color.from_string ("white"));
            text.anchor_gravity = Gravity.CENTER;
            text.x = stage.width / 2;
            text.y = stage.height / 2;
            text.opacity = 0;
            stage.add_actor (text);
            text.animate (AnimationMode.LINEAR, TRANSITION,
                          opacity: 255);
            return false;
        }
        
        image.keep_aspect_ratio = true;
        image.set_request_mode(Clutter.RequestMode.WIDTH_FOR_HEIGHT);
        image.height = stage.height;
        
        if (image.width > stage.width) {
            image.set_request_mode(Clutter.RequestMode.HEIGHT_FOR_WIDTH);
            image.width = stage.width;
        }
        
        //image.x = this.stage.width / 2 - image.width / 2;
        image.x = this.stage.width;
        //image.y = -image.width;
        image.y = this.stage.height / 2 - image.height / 2;
        
        image.animate(Clutter.AnimationMode.LINEAR, TRANSITION, "x", this.stage.width / 2 - image.width / 2);
        
        this.image = image;
        
        stage.add_actor(image);
        
        
        return true;
    }

    public void start () {
            var text_group = new Group();
 
            var shadow = new Text.full ("Bitstream Vera Sans 40",
                                        "Congratulations!",
                                        Color.from_string ("black"));
            shadow.add_effect(new BlurEffect());
            text_group.add_actor(shadow);

            var text = new Text.full ("Bitstream Vera Sans 40",
                                      "Congratulations!",
                                      Color.from_string ("white"));
            text_group.add_actor(text);
            text_group.anchor_gravity = Gravity.CENTER;
            text_group.x = stage.width / 2;
            text_group.y = -text_group.height;    // Off-stage
            
            text.animate (AnimationMode.EASE_IN_OUT_BOUNCE, 3000,
                          y: stage.height / 2);

    }
}

void main (string[] args) {
    Clutter.init (ref args);
    Gst.init(ref args);
    var demo = new ClutterDemo (args[1:args.length]);
    demo.start ();
    Clutter.main ();
}