m2-GTK4/examples/media.mod

MODULE media ;

(*
   m2-GTK4 example - media: a GdkTexture shown in a GtkPicture.

   Generates a PNG with Cairo at run time, loads it as a texture and
   displays it; a GtkVideo widget is added as a placeholder.

   Build:  make examples
   Run:    ./build/examples/media
*)

FROM Gio IMPORT g_application_run;
FROM GtkApplication IMPORT gtk_application_new;
FROM GtkWindow IMPORT gtk_application_window_new, gtk_window_set_title,
   gtk_window_set_default_size, gtk_window_set_child, gtk_window_present;
FROM GtkBox IMPORT gtk_box_new, gtk_box_append, gtk_box_set_spacing;
FROM GtkEnums IMPORT GtkVertical;
FROM GtkPicture IMPORT gtk_picture_new, gtk_picture_set_paintable;
FROM GtkVideo IMPORT gtk_video_new;
FROM GdkTexture IMPORT gdk_texture_new_from_filename;
FROM GError IMPORT GError;
FROM Cairo IMPORT cairo_image_surface_create, cairo_create, cairo_destroy,
   cairo_surface_destroy, cairo_set_source_rgb, cairo_rectangle, cairo_fill,
   cairo_surface_write_to_png, CairoFormatARGB32;
FROM GtkClosures IMPORT Connect2;
FROM GtkUtils IMPORT ClearError;
FROM SYSTEM IMPORT ADDRESS, ADR;
FROM libc IMPORT printf;

CONST
   AppId = "org.example.m2gtk4.Media";
   PngPath = "/tmp/opencode/m2media_demo.png";

PROCEDURE MakePng;
VAR
   surface, cr: ADDRESS;
BEGIN
   surface := cairo_image_surface_create(CairoFormatARGB32, 200, 120);
   cr := cairo_create(surface);
   cairo_set_source_rgb(cr, 0.16, 0.50, 0.72);
   cairo_rectangle(cr, 0.0, 0.0, 200.0, 120.0);
   cairo_fill(cr);
   cairo_destroy(cr);
   cairo_surface_write_to_png(surface, PngPath);
   cairo_surface_destroy(surface)
END MakePng;

PROCEDURE OnActivate (application: ADDRESS; data: ADDRESS);
VAR
   window, box, picture, video, texture: ADDRESS;
   err: GError;
BEGIN
   MakePng();

   err := NIL;
   texture := gdk_texture_new_from_filename(PngPath, err);
   picture := gtk_picture_new();
   IF texture # NIL THEN
      gtk_picture_set_paintable(picture, texture)
   ELSE
      printf("could not load %s\n", PngPath);
      ClearError(err)
   END;

   video := gtk_video_new();

   box := gtk_box_new(GtkVertical, 8);
   gtk_box_set_spacing(box, 8);
   gtk_box_append(box, picture);
   gtk_box_append(box, video);

   window := gtk_application_window_new(application);
   gtk_window_set_title(window, "m2-GTK4 Media");
   gtk_window_set_default_size(window, 320, 320);
   gtk_window_set_child(window, box);
   gtk_window_present(window)
END OnActivate;

VAR
   app: ADDRESS;
BEGIN
   app := gtk_application_new(AppId, 0);
   IF app = NIL THEN
      printf("gtk_application_new failed\n");
      HALT(1)
   END;
   Connect2(app, "activate", OnActivate, NIL);
   g_application_run(app, 0, NIL)
END media.