Re: Render Text to Pixbuf

[John Spray <jcspray icculus org>]

On Mon, 2007-04-30 at 14:32 -0500, Paul Davis wrote:
> Hey,
> 
> I'm working on trying to render text to a image that eventually gets
> painted on screen. Basically all I have access to is a Gdk::Pixbuf
> which I edit directly when I'm trying to do the text rendering.

Here's some code that I wrote quickly a while ago, no guarantees as to
how good/right it is.  GTK+ I'm afraid, but you should have no trouble
translating to gtkmm.

John

GdkPixbuf *DrawOverlay (GdkPixbuf *pb, int w, int h, gchar *text)
{ 
  GdkPixmap *pm = gdk_pixmap_new (NULL, w, h, 24);
    
    
  GdkGC *gc = gdk_gc_new (pm);
  gdk_draw_pixbuf (pm, gc, pb,
    0, 0, 0, 0,
    w, h,
    GDK_RGB_DITHER_NONE, 
    0,
    0);

  GtkWidget *scratch = gtk_window_new (GTK_WINDOW_TOPLEVEL);
  gtk_widget_realize (scratch);
  PangoLayout *layout = gtk_widget_create_pango_layout (scratch, NULL);
  gtk_widget_destroy (scratch);

  gchar *markup = g_strdup_printf (
    "<big><b><span foreground='#FFFF00'>%s</span></b></big>", text);
  pango_layout_set_markup (layout, markup, -1);
  g_free (markup);

  gdk_draw_layout (pm, gc, 10, 10, layout);
  g_object_unref (layout);

  GdkPixbuf *ret = gdk_pixbuf_get_from_drawable
    (NULL,
    pm,
    NULL,
    0,
    0,
    0,
    0,
    w,
    h);

  return ret;
}