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require 'rvg/rvg'
Magick::RVG.dpi = 90
rvg = Magick::RVG.new(12.cm, 6.cm).viewbox(0, 0, 1200, 600) do |canvas|
canvas.title = 'Example quad01 - quadratic Bezier commands in path data'
canvas.desc = <<-END_DESC
Picture showing a "Q" a "T" command, along with annotations showing the
control points and end points
END_DESC
canvas.background_fill = 'white'
canvas.rect(1195, 592, 1, 1).styles(fill: 'none', stroke: 'blue', stroke_width: 1)
canvas.path('M200,300 Q400,50 600,300 T1000,300')
.styles(fill: 'none', stroke: 'red', stroke_width: 5)
# End points
canvas.g.styles(fill: 'black') do |grp|
grp.circle(10, 200, 300)
grp.circle(10, 600, 300)
grp.circle(10, 1000, 300)
end
# Control points and lines from end points to control points
canvas.g.styles(fill: '#888') do |grp|
grp.circle(10, 400, 50)
grp.circle(10, 800, 550)
end
canvas.path('M200,300 L400,50 L600,300 L800,550 L1000,300')
.styles(fill: 'none', stroke: '#888', stroke_width: 2)
end
rvg.draw.write('quad01.gif')
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