blog-static/code/patterns/patterns_genbase.rb

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1.4 KiB
Ruby
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require 'victor'
BASE = 4
DIRS = 7
def sum_digits(n)
x = n % BASE
x == 0 ? BASE : x
end
def step(x, y, n, dir)
return [n*Math.cos(2*Math::PI/DIRS*dir), n*Math.sin(2*Math::PI/DIRS*dir), (dir+1) % DIRS]
end
def run_number(number)
counter = 1
x, y, dir = 0.0, 0.0, 0
line_stack = [[0,0]]
(BASE/BASE.gcd(number) * DIRS).times do |i|
dx, dy, dir = step(x,y, sum_digits(i*number), dir)
x += dx
y += dy
line_stack << [x,y]
end
puts line_stack.to_s
return make_svg(line_stack)
end
def make_svg(line_stack)
line_length = 20
xs = line_stack.map { |c| c[0] }
ys = line_stack.map { |c| c[1] }
x_offset = -xs.min
y_offset = -ys.min
svg_coords = ->(p) {
nx, ny = p
[(nx+x_offset)*line_length + line_length/2, (ny+y_offset)*line_length + line_length/2]
}
max_width = (xs.max - xs.min).abs * line_length + line_length
max_height = (ys.max - ys.min).abs * line_length + line_length
svg = Victor::SVG.new width: max_width, height: max_height
style = { stroke: 'black', stroke_width: 5 }
svg.build do
line_stack.each_cons(2) do |pair|
p1, p2 = pair
x1, y1 = svg_coords.call(p1)
x2, y2 = svg_coords.call(p2)
line x1: x1, y1: y1, x2: x2, y2: y2, style: style
circle cx: x2, cy: y2, r: line_length/6, style: style, fill: 'black'
end
end
return svg
end
(1..10).each do |i|
run_number(i).save "pattern_#{i}"
end