Sierpinski curve: Difference between revisions

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Line 4: Produce a graphical or ASCII-art representation of a [[wp:Sierpiński_curve\|Sierpinski curve]] of at least order 3. =={{header\|11l}}== {{trans\|C++}} <syntaxhighlight lang="11l">T SierpinskiCurve . Float x, y . Int angle, length . F line(out) V theta = radians(Float(.angle)) .x += .length * cos(theta) .y -= .length * sin(theta) out.write(‘ L’gconvfmt(.x)‘,’gconvfmt(.y)) . F execute(out, s) out.write(‘M’gconvfmt(.x)‘,’gconvfmt(.y)) L(c) s S c ‘F’, ‘G’ .line(out) ‘+’ .angle = (.angle + 45) % 360 ‘-’ .angle = (.angle - 45) % 360 . F :rewrite(s) V t = ‘’ L(c) s I c == ‘X’ t ‘’= ‘XF+G+XF--F--XF+G+X’ E t ‘’= c R t F write(out, size, length, order) .length = length .x = length / sqrt(2) .y = .x * 2 .angle = 45 out.write(‘<svg xmlns='http://www.w3.org/2000/svg' width='’size‘' height='’size"'>\n") out.write("<rect width='100%' height='100%' fill='white'/>\n") out.write(‘<path stroke-width='1' stroke='black' fill='none' d='’) V s = ‘F--XF--F--XF’ L 0 .< order s = .:rewrite(s) .execute(out, s) out.write("'/>\n</svg>\n") V out = File(‘sierpinski_curve.svg’, WRITE) SierpinskiCurve().write(out, 545, 7, 5)</syntaxhighlight> {{out}} Same as C++ output. =={{header\|Action!}}== Action! language does not support recursion. Therefore an iterative approach with a stack has been proposed. <syntaxhighlight lang="action!">DEFINE C_="10+" DEFINE N_="20+" DEFINE E_="30+" DEFINE S_="40+" DEFINE W_="50+" DEFINE SafePlot="BYTE inside inside=InsideScreen() IF inside THEN Plot(x,y) FI" DEFINE SafeDrawTo="IF inside=1 AND InsideScreen()=1 THEN DrawTo(x,y) FI" DEFINE Next="Push(state+1,level)" DEFINE DrawN="Push(21,level-1)" DEFINE DrawE="Push(31,level-1)" DEFINE DrawS="Push(41,level-1)" DEFINE DrawW="Push(51,level-1)" INT x,y,stackSize DEFINE MAX_COUNT="100" BYTE ARRAY stack(MAX_COUNT) PROC InitStack() stackSize=0 RETURN BYTE FUNC IsEmpty() IF stackSize=0 THEN RETURN (1) FI RETURN (0) PROC Push(BYTE state,level) stack(stackSize)=state stackSize==+1 stack(stackSize)=level stackSize==+1 RETURN PROC Pop(BYTE POINTER state,level) stackSize==-1 level^=stack(stackSize) stackSize==-1 state^=stack(stackSize) RETURN BYTE FUNC InsideScreen() IF x<0 OR y<0 OR x>319 OR y>191 THEN RETURN (0) FI RETURN (1) PROC LineN() SafePlot y==-4 SafeDrawTo RETURN PROC LineNE() SafePlot x==+2 y==-2 SafeDrawTo RETURN PROC LineE() SafePlot x==+4 SafeDrawTo RETURN PROC LineSE() SafePlot x==+2 y==+2 SafeDrawTo RETURN PROC LineS() SafePlot y==+4 SafeDrawTo RETURN PROC LineSW() SafePlot x==-2 y==+2 SafeDrawTo RETURN PROC LineW() SafePlot x==-4 SafeDrawTo RETURN PROC LineNW() SafePlot x==-2 y==-2 SafeDrawTo RETURN PROC SierpinskiCurve(BYTE level) BYTE state InitStack() Push(C_ 1,level+1) WHILE IsEmpty()=0 DO Pop(@state,@level) IF state=C_ 1 THEN Next DrawN ELSEIF state=C_ 2 THEN LineNE() Next DrawE ELSEIF state=C_ 3 THEN LineSE() Next DrawS ELSEIF state=C_ 4 THEN LineSW() Next DrawW ELSEIF state=C_ 5 THEN LineNW() ELSEIF state=N_ 1 THEN IF level=1 THEN LineNE() LineN() LineNW() ELSE Next DrawN FI ELSEIF state=N_ 2 THEN LineNE() Next DrawE ELSEIF state=N_ 3 THEN LineN() Next DrawW ELSEIF state=N_ 4 THEN LineNW() DrawN ELSEIF state=E_ 1 THEN IF level=1 THEN LineSE() LineE() LineNE() ELSE Next DrawE FI ELSEIF state=E_ 2 THEN LineSE() Next DrawS ELSEIF state=E_ 3 THEN LineE() Next DrawN ELSEIF state=E_ 4 THEN LineNE() DrawE ELSEIF state=S_ 1 THEN IF level=1 THEN LineSW() LineS() LineSE() ELSE Next DrawS FI ELSEIF state=S_ 2 THEN LineSW() Next DrawW ELSEIF state=S_ 3 THEN LineS() Next DrawE ELSEIF state=S_ 4 THEN LineSE() DrawS ELSEIF state=W_ 1 THEN IF level=1 THEN LineNW() LineW() LineSW() ELSE Next DrawW FI ELSEIF state=W_ 2 THEN LineNW() Next DrawN ELSEIF state=W_ 3 THEN LineW() Next DrawS ELSEIF state=W_ 4 THEN LineSW() DrawW ELSE Break() FI OD RETURN PROC Main() BYTE CH=$02FC,COLOR1=$02C5,COLOR2=$02C6 Graphics(8+16) Color=1 COLOR1=$0C COLOR2=$02 x=1 y=187 SierpinskiCurve(6) DO UNTIL CH#$FF OD CH=$FF RETURN</syntaxhighlight> {{out}} [https://gitlab.com/amarok8bit/action-rosetta-code/-/raw/master/images/Sierpinski_curve.png Screenshot from Atari 8-bit computer] =={{header\|ALGOL W}}== Using code from the [[Sierpinski arrowhead curve]] task.<br> Curve algorithm based on the XPL0 sample. <syntaxhighlight lang="algolw"> begin % draw sierpinski curves using ascii art % integer CANVAS_WIDTH; CANVAS_WIDTH := 200; begin % the ascii art canvas and related items % string(1) array canvas ( 1 :: CANVAS_WIDTH, 1 :: CANVAS_WIDTH ); integer heading, asciiX, asciiY, width, maxX, maxY, minX, minY; % draw a line using ascii art - the length is ignored and the heading determines the % % character to use % % the position is updated % procedure drawLine( real value length ) ; begin % stores the min and max coordinates % procedure updateCoordinateRange ; begin if asciiX > maxX then maxX := asciiX; if asciiY > maxY then maxY := asciiY; if asciiX < minX then minX := asciiX; if asciiY < minY then minY := asciiY end updateCoordinateRange ; if heading = 0 then begin updateCoordinateRange; canvas( asciiX, asciiY ) := "_"; asciiX := asciiX + 1 end else if heading = 45 then begin updateCoordinateRange; canvas( asciiX, asciiY ) := "/"; asciiY := asciiY - 1; asciiX := asciiX + 1 end else if heading = 90 then begin updateCoordinateRange; canvas( asciiX, asciiY ) := "\|"; asciiY := asciiY - 1 end else if heading = 135 then begin asciiX := asciiX - 1; updateCoordinateRange; canvas( asciiX, asciiY ) := "\"; asciiY := asciiY - 1 end else if heading = 180 then begin asciiX := asciiX - 1; updateCoordinateRange; canvas( asciiX, asciiY ) := "_" end else if heading = 225 then begin asciiX := asciiX - 1; asciiY := asciiY + 1; updateCoordinateRange; canvas( asciiX, asciiY ) := "/" end else if heading = 270 then begin asciiY := asciiY + 1; updateCoordinateRange; canvas( asciiX - 1, asciiY ) := "\|"; end else if heading = 315 then begin asciiY := asciiY + 1; updateCoordinateRange; canvas( asciiX, asciiY ) := "\"; asciiX := asciiX + 1 end if_various_headings end drawLine ; % changes the heading by the specified angle ( in degrees ) - angle must be +/- 45 % procedure turn( integer value angle ) ; if angle > 0 then heading := ( heading + angle ) rem 360 else begin heading := heading + angle; if heading < 0 then heading := heading + 360 end tuen ; % initialises the ascii art canvas % procedure initArt ; begin heading := 0; asciiX := CANVAS_WIDTH div 2; asciiY := asciiX; maxX := asciiX; maxY := asciiY; minX := asciiX; minY := asciiY; for x := 1 until CANVAS_WIDTH do for y := 1 until CANVAS_WIDTH do canvas( x, y ) := " " end initArt ; % shows the used parts of the canvas % procedure drawArt ; begin for y := minY until maxY do begin write(); for x := minX until maxX do writeon( canvas( x, y ) ) end for_y ; write() end drawIArt ; % draws a sierpinski curve of the specified order and line length % procedure sierpinskiCurve( integer value order ) ; begin % recursively draws a segment of the sierpinski curve % procedure curve( integer value order; integer value angle ) ; if 0 not = order then begin turn( + angle ); curve( order - 1, - angle ); turn( - angle ); drawline( 1 ); if heading rem 180 = 0 then drawline( 1 ); turn( - angle ); curve( order - 1, - angle ); turn( + angle ); end curve ; for Quad := 1 until 4 do begin curve( order * 2, 45 ); turn( 45 ); drawline( 1 ); if heading rem 180 = 0 then drawline( 1 ); turn( 45 ); end for_Quad end sierpinskiCurve ; % draw curves % i_w := 1; s_w := 0; % set output formatting % for order := 3 do begin write( "Sierpinski curve of order ", order ); write( "===========================" ); write(); initArt; sierpinskiCurve( order ); drawArt end for_order end end. </syntaxhighlight> {{out}} <pre> Sierpinski curve of order 3 =========================== /\__/\ /\__/\ /\__/\ /\__/\ \ / \ / \ / \ / \| \| \| \| \| \| \| \| / __ \__/ __ \ / __ \__/ __ \ \/ \ / \/ \/ \ / \/ \| \| \| \| /\__/ __ \__/\ /\__/ __ \__/\ \ / \ / \ / \ / \| \| \| \| \| \| \| \| / __ \ / __ \__/ __ \ / __ \ \/ \/ \/ \ / \/ \/ \/ \| \| /\__/\ /\__/ __ \__/\ /\__/\ \ / \ / \ / \ / \| \| \| \| \| \| \| \| / __ \__/ __ \ / __ \__/ __ \ \/ \ / \/ \/ \ / \/ \| \| \| \| /\__/ __ \__/\ /\__/ __ \__/\ \ / \ / \ / \ / \| \| \| \| \| \| \| \| / __ \ / __ \ / __ \ / __ \ \/ \/ \/ \/ \/ \/ \/ \/ </pre> =={{header\|AutoHotkey}}== {{trans\|Go}} Requires [https://www.autohotkey.com/boards/viewtopic.php?t=6517 Gdip Library] <~~lang~~syntaxhighlight ~~AutoHotkey~~lang="autohotkey">SierpinskiW := 500 SierpinskiH := 500 level := 5 Line 163 ⟶ 548: ExitApp Return </syntaxhighlight> ~~</lang>~~ =={{header\|BASIC}}== ==={{header\|FreeBASIC}}=== {{trans\|XPL0}} <syntaxhighlight lang="vb">#define pi 4 * Atn(1) #define yellow Rgb(255,255,0) Dim Shared As Integer posX, posY Dim Shared As Single direc Sub Dibuja(largo As Integer) posX += Fix(largo * Cos(direc)) posY -= Fix(largo * Sin(direc)) Line - (posX, posY), yellow End Sub Sub Curva(orden As Integer, angulo As Single, long1 As Single, long2 As Single) If orden <> 0 Then direc += angulo Curva(orden-1, -angulo, long1, long2) direc -= angulo Dibuja(long1) direc -= angulo Curva(orden-1, -angulo, long1, long2) direc += angulo End If End Sub Screenres 640, 480, 32 Dim As Single ang45 = pi / 4 Dim As Byte orden = 3 Dim As Byte tam = 20 direc = 0 posX = 640/4 posY = 3480/4 Pset (posX, posY) For c As Byte = 1 To 4 Curva(orden2, ang45, tam/Sqr(2), 5tam/6) direc += ang45 Dibuja(tam/Sqr(2)) direc += ang45 Next Windowtitle "Hit any key to end program" Sleep</syntaxhighlight> ==={{header\|QuickBASIC}}=== {{trans\|XPL0}} <syntaxhighlight lang="qbasic"> REM Sierpinski curve DECLARE SUB Curve (Lev%, Ang!, L1!, L2!) DECLARE SUB DrawLine (L!) CONST Order = 3, Pi = 3.141592654#, Ang45 = Pi / 4!, Size = 20! CONST Sqr2 = 1.4142135623731# DIM SHARED Dir, PosX%, PosY% SCREEN 12 PosX% = 640 \ 4: PosY% = 3 480 \ 4 PSET (PosX%, PosY%) Dir = 0! FOR Quad% = 1 TO 4 CALL Curve(Order * 2, Ang45, Size / Sqr2, 5! * Size / 6!) Dir = Dir + Ang45 CALL DrawLine(Size / Sqr2) Dir = Dir + Ang45 NEXT Quad% END SUB Curve (Lev%, Ang, L1, L2) IF Lev% <> 0 THEN Dir = Dir + Ang CALL Curve(Lev% - 1, -Ang, L1, L2) Dir = Dir - Ang CALL DrawLine(L1) Dir = Dir - Ang CALL Curve(Lev% - 1, -Ang, L1, L2) Dir = Dir + Ang END IF END SUB SUB DrawLine (L) PosX% = PosX% + INT(L * COS(Dir) + .5) PosY% = PosY% - INT(L * SIN(Dir) + .5) LINE -(PosX%, PosY%), 15 END SUB </syntaxhighlight> ==={{header\|Yabasic}}=== <syntaxhighlight lang="yabasic">// Rosetta Code problem: http://rosettacode.org/wiki/Sierpinski_curve // Adapted from https://www.ocg.at/sites/ocg.at/files/EuroLogo2001/P74Batagelj.pdf to Yabasic by Galileo, 01/2022 import turtle sub Sierp(n, a, h, k) if n = 0 move(k) : return turn(a) : Sierp(n - 1, -a, h, k) : turn(-a) : move(h) turn(-a) : Sierp(n - 1, -a, h, k) : turn(a) end sub sub Sierpinski(n, d) local i pen(false) goxy(10, 680) pen(true) color 255, 255, 0 for i = 1 to 4 Sierp(n, 45, d/sqrt(2), 5d/6) turn(45) move(d/sqrt(2)) turn(45) next end sub startTurtle() Sierpinski(9, 12) </syntaxhighlight> =={{header\|C++}}== Output is a file in SVG format. The curve is generated using the Lindenmayer system method. <~~lang~~syntaxhighlight lang="cpp">// See https://en.wikipedia.org/wiki/Sierpi%C5%84ski_curve#Representation_as_Lindenmayer_system #include <cmath> #include <fstream> Line 247 ⟶ 750: s.write(out, 545, 7, 5); return 0; }</~~lang~~syntaxhighlight> {{out}} [[Media:Sierpinski_curve_cpp.svg]] ~~See: [https://slack-files.com/T0CNUL56D-F01GZ1BU4RZ-99f34b7076 sierpinski_curve.svg] (offsite SVG image)~~ =={{header\|EasyLang}}== [https://easylang.online/show/#cod=jZJNbsIwEIX3PsWTFXXRKBa0RSoLb+EQKAs3GLBqnMhOiXP7akgcIGXRle15n+fnaRpfV7ChDzo2sPqiLQRUNPU5g/+xOmS7EoIBONQeFm09UBQBoFwGCc7HJzFVBuMQWl+dlA9jrlEfEQOJJUKrG7wNGd1U7EYCMIcUNyUkquxBBaiYnBDkWJZz4str9Y3lQ1iwZ1ea5eWuSJJCp5pkiXJXVTDBmuTc3qsu6RE9lDvCuiPEkMEapzuzb09YiHcKnOuLJpD9wzBzGEbkG44BleBbfms6Ipeo6oC98XilujetJy0Y90yjrlITALSdKhV32eljIWmiv1w+4/J7TiSXRl9ogqKIm6K4HpxNuyWxA48cPG7ybT4RdOcoWVrN1Xwp2dz61QLrT3yssBBrxn4B Run it] <syntaxhighlight> proc lsysexp level . axiom$ rules$[] . for l to level an$ = "" for c$ in strchars axiom$ for i = 1 step 2 to len rules$[] if rules$[i] = c$ c$ = rules$[i + 1] break 1 . . an$ &= c$ . swap axiom$ an$ . . proc lsysdraw axiom$ x y ang lng . . linewidth 0.3 move x y for c$ in strchars axiom$ if c$ = "F" or c$ = "G" x += cos dir lng y += sin dir * lng line x y elif c$ = "-" dir -= ang elif c$ = "+" dir += ang . . . axiom$ = "F--xF--F--xF" rules$[] = [ "x" "xF+G+xF--F--xF+G+x" ] lsysexp 5 axiom$ rules$[] lsysdraw axiom$ 50 98 45 0.9 </syntaxhighlight> =={{header\|Factor}}== {{works with\|Factor\|0.99 2020-08-14}} <~~lang~~syntaxhighlight lang="factor">USING: accessors kernel L-system sequences ui ; : curve ( L-system -- L-system ) Line 265 ⟶ 808: } >>rules ; [ <L-system> curve "Sierpinski curve" open-window ] with-ui</~~lang~~syntaxhighlight> Line 297 ⟶ 840: \| x \|\| iterate L-system \|} =={{header\|Fōrmulæ}}== {{FormulaeEntry\|page=https://formulae.org/?script=examples/Sierpi%C5%84ski_curve}} '''Solution''' === Recursive === [[File:Fōrmulæ - Sierpiński curve 01.png]] '''Test cases''' [[File:Fōrmulæ - Sierpiński curve 02.png]] [[File:Fōrmulæ - Sierpiński curve 03.png]] === L-system === There are generic functions written in Fōrmulæ to compute an L-system in the page [[L-system#Fōrmulæ \| L-system]]. The program that creates a Sierpiński curve is: [[File:Fōrmulæ - L-system - Sierpiński curve 01.png]] [[File:Fōrmulæ - L-system - Sierpiński curve 02.png]] =={{header\|Go}}== Line 302 ⟶ 871: {{trans\|Phix}} A partial translation anyway which produces a static image of a SC of level 5, yellow on blue, which can be viewed with a utility such as EOG. <~~lang~~syntaxhighlight lang="go">package main import ( Line 419 ⟶ 988: dc.Stroke() dc.SavePNG("sierpinski_curve.png") }</~~lang~~syntaxhighlight> =={{header\|Java}}== {{trans\|C++}} <~~lang~~syntaxhighlight lang="java">import java.io.; public class SierpinskiCurve { Line 513 ⟶ 1,082: private static final String PRODUCTION = "XF+G+XF--F--XF+G+X"; private static final int ANGLE = 45; }</~~lang~~syntaxhighlight> {{out}} [[Media:Sierpinski_curve_java.svg]] ~~See: [https://slack-files.com/T0CNUL56D-F016J6Q8W78-4a6e0291c9 sierpinski_curve.svg] (offsite SVG image)~~ =={{header\|jq}}== {{works with\|jq}} '''Works with gojq, the Go implementation of jq''' This entry uses an L-system and turtle graphics to generate an SVG file which can be viewed using a web browser, at least if the file type is `.svg`. The SVG viewBox is dynamically sized. See [[Category_talk:Jq-turtle]] for the turtle.jq module used here. Please note that the `include` directive may need to be modified depending on the location of the included file, and the command-line options used. <syntaxhighlight lang="jq">include "turtle" {search: "."}; # Compute the curve using a Lindenmayer system of rules def rules: { X: "XF+G+XF--F--XF+G+X", "": "F--XF--F--XF" }; def sierpinski($count): rules as $rules \| def p($count): if $count == 0 then . else gsub("X"; $rules["X"]) \| p($count-1) end; $rules[""] \| p($count) ; def interpret($x): if $x == "+" then turtleRotate(45) elif $x == "-" then turtleRotate(-45) elif $x == "F" or $x == "G" then turtleForward(5) else . end; def sierpinski_curve($n): sierpinski($n) \| split("") \| reduce .[] as $action ( turtle([100,100]) \| turtleDown; interpret($action) ) ; # viewBox = <min-x> <min-y> <width> <height> # Input: {svg, minx, miny, maxx, maxy} def svg: "<svg viewBox='\(.minx\|floor) \(.miny - 2 \|floor) \(.maxx - .minx\|ceil) \(2 + .maxy - .miny\|ceil)'", " preserveAspectRatio='xMinYmin meet'", " xmlns='http://www.w3.org/2000/svg' >", path("none"; "red"; 1), "</svg>"; sierpinski_curve(5) \| svg </syntaxhighlight> =={{header\|Julia}}== ===Turtle procedural (lineto) version=== Modified from [https://craftofcoding.wordpress.com/2018/05/08/recursive-patterns-the-sierpinski-curve/ Craft of Coding blog, Processing version] <~~lang~~syntaxhighlight ~~Julia~~lang="julia">using Luxor function sierpinski_curve(x0, y0, h, level) Line 573 ⟶ 1,195: finish() preview() </syntaxhighlight> ~~</lang>~~ [[File:sierpinski-curve--drawing.png]] ===LSystem version=== <~~lang~~syntaxhighlight lang="julia">using Lindenmayer # https://github.com/cormullion/Lindenmayer.jl sierpcurve = LSystem(Dict("X" => "XF+G+XF--F--XF+G+X"), "F--XF--F--XF") Line 590 ⟶ 1,213: showpreview = true ) </syntaxhighlight> ~~</lang>~~ =={{header\|Lambdatalk}}== <syntaxhighlight lang="scheme"> {def sierp {def sierp.r {lambda {:order :length :angle} {if {= :order 0} then M:length // move :length else {sierp.r {- :order 1} // recurse {/ :length 2} {- :angle}} T:angle // turn :angle {sierp.r {- :order 1} // recurse {/ :length 2} {+ :angle}} T:angle // turn :angle {sierp.r {- :order 1} // recurse {/ :length 2} {- :angle}} }}} {lambda {:order :length} {if {= {% :order 2} 0} // if :order is even then {sierp.r :order :length 60} // recurse with 60° else T60 // else turn 60° {sierp.r :order :length -60} // recurse with -60° }}} Four curves drawn using the turtle promitive. {svg {@ width="580" height="580" style="box-shadow:0 0 8px #000;"} {polyline {@ points="{turtle 50 5 0 {sierp 1 570}}" stroke="#ccc" fill="transparent" stroke-width="7"}} {polyline {@ points="{turtle 50 5 0 {sierp 3 570}}" stroke="#8ff" fill="transparent" stroke-width="5"}} {polyline {@ points="{turtle 50 5 0 {sierp 5 570}}" stroke="#f88" fill="transparent" stroke-width="3"}} {polyline {@ points="{turtle 50 5 0 {sierp 7 570}}" stroke="#000" fill="transparent" stroke-width="1"}} } </syntaxhighlight> See the result in http://lambdaway.free.fr/lambdawalks/?view=sierpinsky =={{header\|Mathematica}} / {{header\|Wolfram Language}}== <syntaxhighlight lang ~~Mathematica~~="mathematica">Graphics[SierpinskiCurve[3]]</~~lang~~syntaxhighlight> =={{header\|Nim}}== {{trans\|C++}} We produce a SVG file using same algorithm as the one of C++ version. <syntaxhighlight lang="nim">import math type SierpinskiCurve = object x, y: float angle: float length: int file: File proc line(sc: var SierpinskiCurve) = let theta = degToRad(sc.angle) sc.x += sc.length.toFloat cos(theta) sc.y -= sc.length.toFloat * sin(theta) sc.file.write " L", sc.x, ',', sc.y proc execute(sc: var SierpinskiCurve; s: string) = sc.file.write 'M', sc.x, ',', sc.y for c in s: case c of 'F', 'G': sc.line() of '+': sc.angle = floorMod(sc.angle + 45, 360) of '-': sc.angle = floorMod(sc.angle - 45, 360) else: discard func rewrite(s: string): string = for c in s: if c == 'X': result.add "XF+G+XF--F--XF+G+X" else: result.add c proc write(sc: var SierpinskiCurve; size, length, order: int) = sc.length = length sc.x = length.toFloat / sqrt(2.0) sc.y = 2 * sc.x sc.angle = 45 sc.file.write "<svg xmlns='http://www.w3.org/2000/svg' width='", size, "' height='", size, "'>\n" sc.file.write "<rect width='100%' height='100%' fill='white'/>\n" sc.file.write "<path stroke-width='1' stroke='black' fill='none' d='" var s = "F--XF--F--XF" for _ in 1..order: s = s.rewrite() sc.execute(s) sc.file.write "'/>\n</svg>\n" let outfile = open("sierpinski_curve.svg", fmWrite) var sc = SierpinskiCurve(file: outfile) sc.write(545, 7, 5) outfile.close()</syntaxhighlight> {{out}} Same as C++ output. =={{header\|Perl}}== <~~lang~~syntaxhighlight lang="perl">use strict; use warnings; use SVG; Line 633 ⟶ 1,361: open my $fh, '>', 'sierpinski-curve.svg'; print $fh $svg->xmlify(-namespace=>'svg'); close $fh;</~~lang~~syntaxhighlight> See: [https://github.com/SqrtNegInf/Rosettacode-Perl5-Smoke/blob/master/ref/sierpinski-curve.svg sierpinski-curve.svg] (offsite SVG image) =={{header\|Phix}}== {{libheader\|Phix/pGUI}} {{libheader\|Phix/online}} ~~<lang Phix>-- demo\rosetta\Sierpinski_curve.exw~~ You can run this online [http://phix.x10.mx/p2js/Sierpinski_curve.htm here]. -- <!--<syntaxhighlight lang="phix">(phixonline)--> ~~-- Draws curves lo to hi (simultaneously), initially {1,1}, max {8,8}~~ <span style="color: #000080;font-style:italic;">-- ~~-- Press +/- to change hi, shift +/- to change lo.~~ -- demo\rosetta\Sierpinski_curve.exw ~~-- ("=_" are also mapped to "+-", for the non-numpad +/-)~~ -- ================================= -- -- ~~include pGUI.e~~ -- Draws curves lo to hi (simultaneously), initially {1,1}, max {8,8} -- Press +/- to change hi, shift +/- to change lo, ctrl +/- for both. -- ("=_" are also mapped to "+-", for the non-numpad +/-) --</span> <span style="color: #008080;">with</span> <span style="color: #008080;">javascript_semantics</span> <span style="color: #008080;">include</span> <span style="color: #000000;">pGUI</span><span style="color: #0000FF;">.</span><span style="color: #000000;">e</span> <span style="color: #004080;">Ihandle</span> <span style="color: #000000;">dlg</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">canvas</span> <span style="color: #004080;">cdCanvas</span> <span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">cdcanvas</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">width</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">height</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">lm</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">tm</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span><span style="color: #0000FF;">,</span> <span style="color: #000080;font-style:italic;">-- left and top margins</span> <span style="color: #000000;">lo</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">hi</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span> <span style="color: #004080;">atom</span> <span style="color: #000000;">cx</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">cy</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">h</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #004080;">atom</span> <span style="color: #000000;">newX</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">newY</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">cdCanvasVertex</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">newX</span><span style="color: #0000FF;">-</span><span style="color: #000000;">width</span><span style="color: #0000FF;">/</span><span style="color: #000000;">2</span><span style="color: #0000FF;">+</span><span style="color: #000000;">h</span><span style="color: #0000FF;">+</span><span style="color: #000000;">lm</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">height</span><span style="color: #0000FF;">-</span><span style="color: #000000;">newY</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span><span style="color: #0000FF;"></span><span style="color: #000000;">h</span><span style="color: #0000FF;">+</span><span style="color: #000000;">tm</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">cx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">newX</span> <span style="color: #000000;">cy</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">newY</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineN</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">-</span><span style="color: #000000;">2</span><span style="color: #0000FF;"></span><span style="color: #000000;">h</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineS</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span><span style="color: #0000FF;"></span><span style="color: #000000;">h</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span><span style="color: #0000FF;"></span><span style="color: #000000;">h</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">-</span><span style="color: #000000;">2</span><span style="color: #0000FF;"></span><span style="color: #000000;">h</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineNW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">-</span><span style="color: #000000;">h</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">-</span><span style="color: #000000;">h</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineNE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">+</span><span style="color: #000000;">h</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">-</span><span style="color: #000000;">h</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineSE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">+</span><span style="color: #000000;">h</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">h</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">lineSW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineTo</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cx</span><span style="color: #0000FF;">-</span><span style="color: #000000;">h</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cy</span><span style="color: #0000FF;">+</span><span style="color: #000000;">h</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">forward</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">forward</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">forward</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">forward</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lineNE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineN</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineNW</span><span style="color: #0000FF;">()</span> <span style="color: #008080;">else</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineNE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineN</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineNW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lineSE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineNE</span><span style="color: #0000FF;">()</span> <span style="color: #008080;">else</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineSE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineNE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lineSW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineS</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineSE</span><span style="color: #0000FF;">()</span> <span style="color: #008080;">else</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineSW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineS</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineSE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lineNW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">lineSW</span><span style="color: #0000FF;">()</span> <span style="color: #008080;">else</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineNW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineSW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">sierpinskiCurve</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">sierN</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineNE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierE</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineSE</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierS</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineSW</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">sierW</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">lineNW</span><span style="color: #0000FF;">()</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">function</span> <span style="color: #000000;">redraw_cb</span><span style="color: #0000FF;">(</span><span style="color: #004080;">Ihandle</span> <span style="color: #000080;font-style:italic;">/ih/</span><span style="color: #0000FF;">)</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">width</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">height</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">IupGetIntInt</span><span style="color: #0000FF;">(</span><span style="color: #000000;">canvas</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"DRAWSIZE"</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">width</span><span style="color: #0000FF;">></span><span style="color: #000000;">height</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lm</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">((</span><span style="color: #000000;">width</span><span style="color: #0000FF;">-</span><span style="color: #000000;">height</span><span style="color: #0000FF;">)/</span><span style="color: #000000;">2</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">tm</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> <span style="color: #000000;">width</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">height</span> <span style="color: #008080;">else</span> <span style="color: #000000;">lm</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">0</span> <span style="color: #000000;">tm</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">((</span><span style="color: #000000;">height</span><span style="color: #0000FF;">-</span><span style="color: #000000;">width</span><span style="color: #0000FF;">)/</span><span style="color: #000000;">2</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">height</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">width</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #7060A8;">cdCanvasActivate</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">for</span> <span style="color: #000000;">level</span><span style="color: #0000FF;">=</span><span style="color: #000000;">lo</span> <span style="color: #008080;">to</span> <span style="color: #000000;">hi</span> <span style="color: #008080;">do</span> <span style="color: #000000;">cx</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">width</span><span style="color: #0000FF;">/</span><span style="color: #000000;">2</span> <span style="color: #000000;">cy</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">height</span> <span style="color: #000000;">h</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cx</span><span style="color: #0000FF;">/</span><span style="color: #7060A8;">power</span><span style="color: #0000FF;">(</span><span style="color: #000000;">2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">level</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">cdCanvasBegin</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">,</span> <span style="color: #004600;">CD_CLOSED_LINES</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">sierpinskiCurve</span><span style="color: #0000FF;">(</span><span style="color: #000000;">level</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">cdCanvasEnd</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">for</span> <span style="color: #7060A8;">cdCanvasFlush</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">return</span> <span style="color: #004600;">IUP_DEFAULT</span> <span style="color: #008080;">end</span> <span style="color: #008080;">function</span> <span style="color: #008080;">function</span> <span style="color: #000000;">map_cb</span><span style="color: #0000FF;">(</span><span style="color: #004080;">Ihandle</span> <span style="color: #000000;">ih</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">cdcanvas</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">cdCreateCanvas</span><span style="color: #0000FF;">(</span><span style="color: #004600;">CD_IUP</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ih</span><span style="color: #0000FF;">)</span> <span style="color: #000000;">cddbuffer</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">cdCreateCanvas</span><span style="color: #0000FF;">(</span><span style="color: #004600;">CD_DBUFFER</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">cdcanvas</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">cdCanvasSetBackground</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">,</span> <span style="color: #004600;">CD_WHITE</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">cdCanvasSetForeground</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">,</span> <span style="color: #004600;">CD_BLUE</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">return</span> <span style="color: #004600;">IUP_DEFAULT</span> <span style="color: #008080;">end</span> <span style="color: #008080;">function</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">set_dlg_title</span><span style="color: #0000FF;">()</span> <span style="color: #7060A8;">IupSetStrAttribute</span><span style="color: #0000FF;">(</span><span style="color: #000000;">dlg</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"TITLE"</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"Sierpinski curve (%d..%d)"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">,</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">})</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #008080;">function</span> <span style="color: #000000;">key_cb</span><span style="color: #0000FF;">(</span><span style="color: #004080;">Ihandle</span> <span style="color: #000080;font-style:italic;">/ih/</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">atom</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #004600;">K_ESC</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">IUP_CLOSE</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">if</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #004600;">K_F5</span> <span style="color: #008080;">then</span> <span style="color: #008080;">return</span> <span style="color: #004600;">IUP_DEFAULT</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000080;font-style:italic;">-- (let browser reload work)</span> <span style="color: #000000;">c</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">iup_XkeyBase</span><span style="color: #0000FF;">(</span><span style="color: #000000;">c</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #7060A8;">find</span><span style="color: #0000FF;">(</span><span style="color: #000000;">c</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"+=-_"</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #004080;">bool</span> <span style="color: #000000;">bCtrl</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">IupGetInt</span><span style="color: #0000FF;">(</span><span style="color: #004600;">NULL</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"CONTROLKEY"</span><span style="color: #0000FF;">),</span> <span style="color: #000000;">bShift</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">IupGetInt</span><span style="color: #0000FF;">(</span><span style="color: #004600;">NULL</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"SHIFTKEY"</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'+'</span> <span style="color: #008080;">or</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'='</span> <span style="color: #008080;">then</span> <span style="color: #008080;">if</span> <span style="color: #000000;">bCtrl</span> <span style="color: #008080;">or</span> <span style="color: #008080;">not</span> <span style="color: #000000;">bShift</span> <span style="color: #008080;">then</span> <span style="color: #000000;">hi</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">min</span><span style="color: #0000FF;">(</span><span style="color: #000000;">8</span><span style="color: #0000FF;">,</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">if</span> <span style="color: #000000;">bCtrl</span> <span style="color: #008080;">or</span> <span style="color: #000000;">bShift</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lo</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">min</span><span style="color: #0000FF;">(</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">elsif</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'-'</span> <span style="color: #008080;">or</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">=</span><span style="color: #008000;">'_'</span> <span style="color: #008080;">then</span> <span style="color: #008080;">if</span> <span style="color: #000000;">bCtrl</span> <span style="color: #008080;">or</span> <span style="color: #000000;">bShift</span> <span style="color: #008080;">then</span> <span style="color: #000000;">lo</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">max</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">if</span> <span style="color: #000000;">bCtrl</span> <span style="color: #008080;">or</span> <span style="color: #008080;">not</span> <span style="color: #000000;">bShift</span> <span style="color: #008080;">then</span> <span style="color: #000000;">hi</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">max</span><span style="color: #0000FF;">(</span><span style="color: #000000;">lo</span><span style="color: #0000FF;">,</span><span style="color: #000000;">hi</span><span style="color: #0000FF;">-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #000000;">set_dlg_title</span><span style="color: #0000FF;">()</span> <span style="color: #7060A8;">cdCanvasClear</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cddbuffer</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">IupUpdate</span><span style="color: #0000FF;">(</span><span style="color: #000000;">canvas</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">return</span> <span style="color: #004600;">IUP_CONTINUE</span> <span style="color: #008080;">end</span> <span style="color: #008080;">function</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">main</span><span style="color: #0000FF;">()</span> <span style="color: #7060A8;">IupOpen</span><span style="color: #0000FF;">()</span> <span style="color: #000000;">canvas</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">IupCanvas</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"RASTERSIZE=770x770"</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">IupSetCallbacks</span><span style="color: #0000FF;">(</span><span style="color: #000000;">canvas</span><span style="color: #0000FF;">,</span> <span style="color: #0000FF;">{</span><span style="color: #008000;">"MAP_CB"</span><span style="color: #0000FF;">,</span> <span style="color: #7060A8;">Icallback</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"map_cb"</span><span style="color: #0000FF;">),</span> <span style="color: #008000;">"ACTION"</span><span style="color: #0000FF;">,</span> <span style="color: #7060A8;">Icallback</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"redraw_cb"</span><span style="color: #0000FF;">)})</span> <span style="color: #000000;">dlg</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">IupDialog</span><span style="color: #0000FF;">(</span><span style="color: #000000;">canvas</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">IupSetCallback</span><span style="color: #0000FF;">(</span><span style="color: #000000;">dlg</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"KEY_CB"</span><span style="color: #0000FF;">,</span> <span style="color: #7060A8;">Icallback</span><span style="color: #0000FF;">(</span><span style="color: #008000;">"key_cb"</span><span style="color: #0000FF;">))</span> <span style="color: #000000;">set_dlg_title</span><span style="color: #0000FF;">()</span> <span style="color: #7060A8;">IupShow</span><span style="color: #0000FF;">(</span><span style="color: #000000;">dlg</span><span style="color: #0000FF;">)</span> <span style="color: #7060A8;">IupSetAttribute</span><span style="color: #0000FF;">(</span><span style="color: #000000;">canvas</span><span style="color: #0000FF;">,</span> <span style="color: #008000;">"RASTERSIZE"</span><span style="color: #0000FF;">,</span> <span style="color: #004600;">NULL</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">if</span> <span style="color: #7060A8;">platform</span><span style="color: #0000FF;">()!=</span><span style="color: #004600;">JS</span> <span style="color: #008080;">then</span> <span style="color: #7060A8;">IupMainLoop</span><span style="color: #0000FF;">()</span> <span style="color: #7060A8;">IupClose</span><span style="color: #0000FF;">()</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span> <span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span> <span style="color: #000000;">main</span><span style="color: #0000FF;">()</span> <!--</syntaxhighlight>--> =={{header\|Processing}}== ~~Ihandle dlg, canvas~~ {{trans\|Go}} ~~cdCanvas cddbuffer, cdcanvas~~ <syntaxhighlight lang="processing"> // https://rosettacode.org/wiki/Sierpinski_curve#C.2B.2B ~~integer width, height,~~ // translation of the GO code https://rosettacode.org/wiki/Sierpinski_curve#Go ~~lo = 1, hi = 1~~ // output on github at: https://github.com/rupertrussell/sierpinski_curve ~~atom cx, cy, h~~ // animated gif created using: https://ezgif.com/ int width = 770; int height = 770; int level = 6; float cx = width / 2; float cy = height; float oldx = width/2; ~~procedure lineTo(atom newX, newY)~~ float oldy = height; ~~cdCanvasVertex(cddbuffer, newX-width/2+h, height-newY+2h)~~ ~~cx = newX~~ ~~cy = newY~~ ~~end procedure~~ ~~procedure lineN() lineTo(cx,cy-2h) end procedure~~ ~~procedure lineS() lineTo(cx,cy+2h) end procedure~~ ~~procedure lineE() lineTo(cx+2h,cy) end procedure~~ ~~procedure lineW() lineTo(cx-2h,cy) end procedure~~ float h = cx / pow(2, (level+1)); ~~procedure lineNW() lineTo(cx-h,cy-h) end procedure~~ int count = 0; ~~procedure lineNE() lineTo(cx+h,cy-h) end procedure~~ ~~procedure lineSE() lineTo(cx+h,cy+h) end procedure~~ ~~procedure lineSW() lineTo(cx-h,cy+h) end procedure~~ void setup() { ~~procedure sierN(integer level)~~ size(770, 770); ~~if level=1 then~~ noLoop(); // stop draw from looping repeatedly ~~lineNE() lineN()~~ } ~~lineNW()~~ ~~else~~ ~~sierN(level-1) lineNE()~~ ~~sierE(level-1) lineN()~~ ~~sierW(level-1) lineNW()~~ ~~sierN(level-1)~~ ~~end if~~ ~~end procedure~~ ~~procedure sierE(integer level)~~ ~~if level=1 then~~ ~~lineSE() lineE()~~ ~~lineNE()~~ ~~else~~ ~~sierE(level-1) lineSE()~~ ~~sierS(level-1) lineE()~~ ~~sierN(level-1) lineNE()~~ ~~sierE(level-1)~~ ~~end if~~ ~~end procedure~~ ~~procedure sierS(integer level)~~ ~~if level=1 then~~ ~~lineSW() lineS()~~ ~~lineSE()~~ ~~else~~ ~~sierS(level-1) lineSW()~~ ~~sierW(level-1) lineS()~~ ~~sierE(level-1) lineSE()~~ ~~sierS(level-1)~~ ~~end if~~ ~~end procedure~~ ~~procedure sierW(integer level)~~ ~~if level=1 then~~ ~~lineNW() lineW()~~ ~~lineSW()~~ ~~else~~ ~~sierW(level-1) lineNW()~~ ~~sierN(level-1) lineW()~~ ~~sierS(level-1) lineSW()~~ ~~sierW(level-1)~~ ~~end if~~ ~~end procedure~~ void draw() { ~~procedure sierpinskiCurve(integer level)~~ background(0, 0, 255); // blue background ~~sierN(level) lineNE()~~ stroke(255, 255, 0); // yellow curve ~~sierE(level) lineSE()~~ ~~sierS~~squareCurve(level) ~~lineSW()~~; ~~sierW~~print(~~level)~~"count = " , ~~lineNW(~~count); save("Sierpinski_Curve_Level" + level + ".png"); ~~end procedure~~ } void squareCurve(int level) { sierN(level); lineNE(); sierE(level); lineSE(); sierS(level); lineSW(); sierW(level); lineNW(); lineNE(); // needed to close the square in the top left hand corner } void lineTo(float newX, float newY) { ~~function redraw_cb(Ihandle /ih/, integer /posx/, integer /posy/)~~ if (count == 0) { ~~{width, height} = IupGetIntInt(canvas, "DRAWSIZE")~~ oldx = newX-width/2+h; ~~cdCanvasActivate(cddbuffer)~~ ~~for~~oldy ~~level~~=lo ~~to hi do~~height-newY+2h; } ~~cx = width/2~~ line(oldx, oldy, ~~cy =~~newX-width/2+h, height-newY+2h); // save("line-" + count + ".png"); // save each step in drawing the curve ~~h = cx/power(2,level+1)~~ cx = newX; ~~cdCanvasBegin(cddbuffer, CD_CLOSED_LINES)~~ cy = newY; ~~sierpinskiCurve(level)~~ ~~cdCanvasEnd(cddbuffer)~~ ~~end for~~ ~~cdCanvasFlush(cddbuffer)~~ ~~return IUP_DEFAULT~~ ~~end function~~ oldx = newX-width/2+h; ~~function map_cb(Ihandle ih)~~ oldy = height-newY+2h; ~~cdcanvas = cdCreateCanvas(CD_IUP, ih)~~ count ++; ~~cddbuffer = cdCreateCanvas(CD_DBUFFER, cdcanvas)~~ } ~~cdCanvasSetBackground(cddbuffer, CD_WHITE)~~ ~~cdCanvasSetForeground(cddbuffer, CD_BLUE)~~ ~~return IUP_DEFAULT~~ ~~end function~~ void lineN() { ~~function key_cb(Ihandle /ih/, atom c)~~ lineTo(cx, cy-2h); ~~if c=K_ESC then return IUP_CLOSE end if~~ } ~~if find(c,"+=-_") then~~ void lineS() { ~~bool bShift = IupGetInt(NULL,"SHIFTKEY")~~ lineTo(cx, cy+2h); ~~if c='+' or c='=' then~~ } ~~if bShift then~~ void lineE() { ~~lo = min(lo+1,hi)~~ lineTo(cx+2h, cy); ~~else~~ } ~~hi = min(8,hi+1)~~ void lineW() { ~~end if~~ lineTo(cx-2h, cy); ~~elsif c='-' or c='_' then~~ } ~~if bShift then~~ void lineNW() { ~~lo = max(1,lo-1)~~ lineTo(cx-h, cy-h); ~~else~~ } ~~hi = max(lo,hi-1)~~ void lineNE() { ~~end if~~ lineTo(cx+h, cy-h); ~~end if~~ } ~~IupSetStrAttribute(dlg, "TITLE", "Sierpinski curve (%d..%d)",{lo,hi})~~ void lineSE() { ~~cdCanvasClear(cddbuffer)~~ lineTo(cx+h, cy+h); ~~IupUpdate(canvas)~~ } ~~end if~~ void lineSW() { ~~return IUP_CONTINUE~~ lineTo(cx-h, cy+h); ~~end function~~ } void sierN(int level) { ~~procedure main()~~ if (level == 1) { ~~IupOpen()~~ lineNE(); lineN(); lineNW(); } else { sierN(level - 1); lineNE(); sierE(level - 1); lineN(); sierW(level - 1); lineNW(); sierN(level - 1); } } void sierE(int level) { if (level == 1) { lineSE(); lineE(); lineNE(); } else { sierE(level - 1); lineSE(); sierS(level - 1); lineE(); sierN(level - 1); lineNE(); sierE(level - 1); } } void sierS(int level) { if (level == 1) { lineSW(); lineS(); lineSE(); } else { sierS(level - 1); lineSW(); sierW(level - 1); lineS(); sierE(level - 1); lineSE(); sierS(level - 1); } } void sierW(int level) { if ( level == 1) { lineNW(); lineW(); lineSW(); } else { sierW(level - 1); lineNW(); sierN(level - 1); lineW(); sierS(level - 1); lineSW(); sierW(level - 1); } } </syntaxhighlight> {{out}} Offsite image at [https://github.com/rupertrussell/sierpinski_curve/blob/main/Sierpinski_Curve_Level5.png Sierpinski_Curve_Level5.png] Offsite image at [https://github.com/rupertrussell/sierpinski_curve/blob/main/Sierpinski_Curve_Level6.png Sierpinski_Curve_Level6.png] Offsite image at [https://github.com/rupertrussell/sierpinski_curve/blob/main/sierpinski_curve.gif level 5 animated gif] =={{header\|Python}}== <syntaxhighlight lang="python">import numpy as np import matplotlib.pyplot as plt from matplotlib.colors import hsv_to_rgb as hsv def curve(axiom, rules, angle, depth): for _ in range(depth): axiom = ''.join(rules[c] if c in rules else c for c in axiom) a, x, y = 0, [0], [0] for c in axiom: match c: case '+': a += 1 case '-': a -= 1 case 'F' \| 'G': x.append(x[-1] + np.cos(aanglenp.pi/180)) y.append(y[-1] + np.sin(aanglenp.pi/180)) l = len(x) # this is very slow, but pretty colors for i in range(l - 1): plt.plot(x[i:i+2], y[i:i+2], color=hsv([i/l, 1, .7])) plt.gca().set_aspect(1) plt.show() curve('F--XF--F--XF', {'X': 'XF+G+XF--F--XF+G+X'}, 45, 5) #curve('F+XF+F+XF', {'X': 'XF-F+F-XF+F+XF-F+F-X'}, 90, 5) #curve('F', {'F': 'G-F-G', 'G': 'F+G+F'}, 60, 7) #curve('A', {'A': '+BF-AFA-FB+', 'B': '-AF+BFB+FA-'}, 90, 6) #curve('FX+FX+', {'X': 'X+YF', 'Y': 'FX-Y'}, 90, 12)</syntaxhighlight> Output in the plot window. =={{header\|Quackery}}== <syntaxhighlight lang="quackery"> [ $ "turtleduck.qky" loadfile ] now! [ stack ] is switch.arg ( --> [ ) [ switch.arg put ] is switch ( x --> ) [ switch.arg release ] is otherwise ( --> ) [ switch.arg share != iff ]else[ done otherwise ]'[ do ]done[ ] is case ( x --> ) [ $ "" swap witheach [ nested quackery join ] ] is expand ( $ --> $ ) [ $ "L" ] is L ( $ --> $ ) ~~canvas = IupCanvas(NULL)~~ ~~IupSetAttribute(canvas, "RASTERSIZE", "770x770")~~ [ $ "R" ] is R ( $ --> $ ) ~~IupSetCallback(canvas, "MAP_CB", Icallback("map_cb"))~~ ~~IupSetCallback(canvas, "ACTION", Icallback("redraw_cb"))~~ [ $ "F" ] is F ( $ --> $ ) [ $ "G" ] is G ( $ --> $ ) ~~dlg = IupDialog(canvas)~~ ~~IupSetAttribute(dlg, "TITLE", "Sierpinski curve (1..1)")~~ [ $ "AFLGLAFRRFRRAFLGLA" ] is A ( $ --> $ ) ~~IupSetCallback(dlg, "K_ANY", Icallback("key_cb"))~~ $ "FRRAFRRFRRAF" 5 times expand [ $ "turtleduck.qky" loadfile ] now! [ stack ] is switch.arg ( --> [ ) [ switch.arg put ] is switch ( x --> ) [ switch.arg release ] is otherwise ( --> ) [ switch.arg share != iff ]else[ done otherwise ]'[ do ]done[ ] is case ( x --> ) [ $ "" swap witheach [ nested quackery join ] ] is expand ( $ --> $ ) [ $ "L" ] is L ( $ --> $ ) [ $ "R" ] is R ( $ --> $ ) [ $ "F" ] is F ( $ --> $ ) [ $ "G" ] is G ( $ --> $ ) [ $ "AFLGLAFRRFRRAFLGLA" ] is A ( $ --> $ ) $ "FRRAFRRFRRAF" 4 times expand turtle 10 frames 1 8 turn witheach [ switch [ char L case [ -1 8 turn ] char R case [ 1 8 turn ] char A case [ ( ignore ) ] otherwise [ 5 1 walk ] ] ] -1 8 turn 1 frames</syntaxhighlight> {{output}} ~~IupMap(dlg)~~ ~~IupShowXY(dlg,IUP_CENTER,IUP_CENTER)~~ ~~IupMainLoop()~~ ~~IupClose()~~ ~~end procedure~~ [[File:Quackery Sierpinski curve.png]] ~~main()</lang>~~ =={{header\|Raku}}== Line 795 ⟶ 1,809: {{works with\|Rakudo\|2020.02}} <syntaxhighlight lang="raku" ~~perl6~~line>use SVG; role Lindenmayer { Line 833 ⟶ 1,847: ], ], );</~~lang~~syntaxhighlight> See: [https://github.com/thundergnat/rc/blob/master/img/sierpinski-curve-perl6.svg Sierpinski-curve-perl6.svg] (offsite SVG image) =={{header\|Rust}}== Program output is a file in SVG format. <~~lang~~syntaxhighlight lang="rust">// [dependencies] // svg = "0.8.0" Line 920 ⟶ 1,934: fn main() { SierpinskiCurve::save("sierpinski_curve.svg", 545, 5).unwrap(); }</~~lang~~syntaxhighlight> {{out}} [[Media:Sierpinski_curve_rust.svg]] ~~See: [https://slack-files.com/T0CNUL56D-F016A6G6Q5D-9e16463547 sierpinski_curve.svg] (offsite SVG image)~~ =={{header\|Sidef}}== Uses the '''LSystem()''' class from [https://rosettacode.org/wiki/Hilbert_curve#Sidef Hilbert curve]. <~~lang~~syntaxhighlight lang="ruby">var rules = Hash( x => 'xF+G+xF--F--xF+G+x', ) Line 943 ⟶ 1,957: ) lsys.execute('F--xF--F--xF', 5, "sierpiński_curve.png", rules)</~~lang~~syntaxhighlight> Output image: [https://github.com/trizen/rc/blob/master/img/sierpi%C5%84ski_curve-sidef.png Sierpiński curve] Line 949 ⟶ 1,963: {{trans\|Go}} {{libheader\|DOME}} <~~lang~~syntaxhighlight ~~ecmascript~~lang="wren">import "graphics" for Canvas, Color import "dome" for Window Line 1,077 ⟶ 2,091: } var Game = SierpinskiCurve.new(770, 770, 5, Color.blue, Color.yellow)</~~lang~~syntaxhighlight> {{out}} [[File:Wren-Sierpinski_curve.png\|400px]] =={{header\|XPL0}}== [[File:SierpenXPL0.gif\|200px\|thumb\|right]] <syntaxhighlight lang "XPL0">int PosX, PosY; real Dir; proc Draw(Len); real Len; [PosX:= PosX + fix(LenCos(Dir)); PosY:= PosY - fix(LenSin(Dir)); Line(PosX, PosY, $E \yellow\); ]; proc Curve(Lev, Ang, Len1, Len2); int Lev; real Ang, Len1, Len2; [if Lev # 0 then [Dir:= Dir + Ang; Curve(Lev-1, -Ang, Len1, Len2); Dir:= Dir - Ang; Draw(Len1); Dir:= Dir - Ang; Curve(Lev-1, -Ang, Len1, Len2); Dir:= Dir + Ang; ]; ]; def Order=3, Pi=3.141592654, Ang45=Pi/4.0, Size=20.; int Quad; [SetVid($12); \VGA graphics: 640x480x8 PosX:= 640/4; PosY:= 3480/4; Move(PosX, PosY); Dir:= 0.; for Quad:= 1 to 4 do [Curve(Order2, Ang45, Size/Sqrt(2.), 5.Size/6.); Dir:= Dir + Ang45; Draw(Size/Sqrt(2.)); Dir:= Dir + Ang45; ]; ]</syntaxhighlight> =={{header\|zkl}}== Uses Image Magick and the PPM class from http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm#zkl <~~lang~~syntaxhighlight lang="zkl">sierpinskiCurve(5) : turtle(_,45,45); // n=5 --> 11,606 characters fcn sierpinskiCurve(order){ Line 1,112 ⟶ 2,168: } img.writeJPGFile("sierpinskiCurve.zkl.jpg"); }</~~lang~~syntaxhighlight> {{out}} Offsite image at [http://www.zenkinetic.com/Images/RosettaCode/sierpinskiCurve.zkl.jpg Sierpinski curve order 5]