fractals examples improved - gsl-shell.git - gsl-shell

diff --git a/examples/fractals.lua b/examples/fractals.lua
index 01fef0ad..92a53a02 100644
--- a/examples/fractals.lua
+++ b/examples/fractals.lua

@@ -26,30 +26,46 @@ local function c_generator(n, n_angle, len_frac, g)

end

end

-local function vonkoch(n)

- local p = plot('Von Koch\'s curve')

- local b = path()

- b:move_to (0, -0.05)

- p:addline(b, 'white')

- p:addline(ipath(c_generator(n, 6, 1/3, {0,1,-1,0})), 'blue')

- p:show()

- return p

-end

-

local function levyc(n)

local p = plot('Levy\'s C curve')

local c = ipath(c_generator(n, 4, 1/2, {-1,0,0,1}))

p:addline(c, 'red', {}, {{'rotate', angle= -pi/4}})

p:addline(c, 'red', {}, {{'translate', x=1/sqrt(2), y=-1/sqrt(2)},{'rotate', angle= pi/4}})

+ p.units = false

p:show()

return p

end

-demo1 = || vonkoch(5)

-demo2 = function()

- local p = levyc(7)

- p.units = false

- end

+function demo1()

+ local pl = plot()

+

+ local t = path()

+ t:move_to(0,0)

+ t:line_to(1,0)

+ t:line_to(0.5,-sqrt(3)/2)

+ t:close()

+

+ local v = ipath(c_generator(4, 6, 1/3, {0,1,-1,0}))

+ local c = rgba(0,0,0.7,0.2)

+ pl:add(v, c)

+ pl:add(v, c, {}, {{'translate', x=1, y=0}, {'rotate', angle=-2*pi/3}})

+ pl:add(v, c, {}, {{'translate', x=0.5, y=-sqrt(3)/2},

+ {'rotate', angle=-2*2*pi/3}})

+ pl:add(t, c)

+

+ c = rgb(0,0,0.7)

+

+ pl:addline(v, c)

+ pl:addline(v, c, {}, {{'translate', x=1, y=0}, {'rotate', angle=-2*pi/3}})

+ pl:addline(v, c, {}, {{'translate', x=0.5, y=-sqrt(3)/2},

+ {'rotate', angle=-2*2*pi/3}})

+

+ pl.units = false

+ pl:show()

+ return pl

+end

+

+demo2 = function(n) return levyc(n and n or 6) end

function demo3()

local rdsd = sqrt(2)/2

@@ -77,6 +93,51 @@ function demo3()

return pl

end

+

+function demo3bis(n)

+ n = n and n or 10

+ local rdsd = sqrt(2)/2

+ local m = new(2^(n+1)-1, 4)

+

+ local function pitag_tree(x, y, th, ll, k, depth)

+ m:set(k, 1, x)

+ m:set(k, 2, y)

+ m:set(k, 3, th)

+ m:set(k, 4, depth)

+ if depth > 0 then

+ x, y = x - ll*sin(th), y + ll*cos(th)

+ k = pitag_tree(x, y, th + pi/4, ll*rdsd, k+1, depth-1)

+ x, y = x + ll*rdsd*cos(th+pi/4), y + ll*rdsd*sin(th+pi/4)

+ k = pitag_tree(x, y, th - pi/4, ll*rdsd, k+1, depth-1)

+ end

+ return k

+ end

+

+ pitag_tree(0, 0, 0, 1, 1, n)

+

+ local cfgen = color_function('darkgreen', 1)

+

+ local pl = plot()

+ pl.units = false

+

+ for d=n, 0, -1 do

+ local dfact = rdsd^(n-d)

+ local box = rect(0, 0, dfact, dfact)

+ for k=1, 2^(n+1)-1 do

+ if m:get(k,4) == d then

+ local x, y, th = m:get(k,1), m:get(k,2), m:get(k,3)

+ local tr = {{'translate', x=x, y=y}, {'rotate', angle=th}}

+ pl:add(box, cfgen(1-d/n), {}, tr)

+ pl:add(box, cfgen(1-(d-1)/n), {{'stroke', width= 2.5*dfact}}, tr)

+ -- pl:addline(box, cfgen(1-(d-1)/n), {}, tr)

+ end

+ end

+ end

+

+ pl:show()

+ return pl

+end

+

print 'demo1() - Von Koch\'s curve'

print 'demo2() - Levy\'s C curve'

print 'demo3() - Pythagorean Tree'