int w, h;
cairo_surface_t *image;
cairo_arc (cr, 128.0, 128.0, 76.8, 0, 2*M_PI);
cairo_clip (cr);
cairo_new_path (cr); /* path not consumed by clip()*/
image = cairo_image_surface_create_from_png ("data/romedalen.png");
w = cairo_image_surface_get_width (image);
h = cairo_image_surface_get_height (image);
cairo_scale (cr, 256.0/w, 256.0/h);
cairo_set_source_surface (cr, image, 0, 0);
cairo_paint (cr);
cairo_surface_destroy (image);