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# Copyright (c) 2005 Ruby-GNOME2 Project Team
# This program is licenced under the same licence as Ruby-GNOME2.
#
# $Id: cairo-text-align-center.rb,v 1.1 2005/10/12 05:38:30 ktou Exp $
=begin
= cairo/Text Align Center
This demo shows how to use GDK and cairo to show text in center.
From http://cairographics.org/samples/text_align_center.html.
=end
require 'common'
module Demo
class CairoTextAlignCenter < CairoWindow
TEXT = "Ruby"
def initialize
super('cairo text align center')
end
def draw(cr)
cr.select_font_face("Sans",
Cairo::FONT_SLANT_NORMAL,
Cairo::FONT_WEIGHT_NORMAL)
cr.set_font_size(0.2)
extents = cr.text_extents(TEXT)
x = 0.5 - (extents.width / 2 + extents.x_bearing)
y = 0.5 - (extents.height / 2 + extents.y_bearing)
cr.move_to(x, y)
cr.show_text(TEXT)
# draw helping lines
cr.set_source_rgba(1, 0.2, 0.2, 0.6)
cr.arc(x, y, 0.05, 0, 2 * Math::PI)
cr.fill
cr.move_to(0.5, 0)
cr.rel_line_to(0, 1)
cr.move_to(0, 0.5)
cr.rel_line_to(1, 0)
cr.stroke
end
end
end
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