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#! /usr/bin/env lua
-- vim:sw=4:sts=4
-- Example by Miles Bader <miles@gnu.org>
require "gtk"
require "cairo"
assert(cairo.version_string())
w = gtk.window_new(gtk.WINDOW_TOPLEVEL)
w:realize()
c = gdk.cairo_create(w.window)
str = "hello"
t_ext = cairo.new 'text_extents_t'
c:text_extents (str, t_ext)
-- look at the structure
-- gtk.dump_struct(t_ext)
-- read double elements of structures
a = t_ext.width
b = t_ext.height
c = t_ext.x_advance
-- write
t_ext.height = 95.5
-- and read again. Check that the surrounding fields haven't changed.
assert(t_ext.width == a)
assert(t_ext.height == 95.5)
assert(t_ext.x_advance == c)
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