Dragon Curve 2

I want to show the dragon curve in five language soluitons:

1. Pascal
2. Python
3. Turtle
4. Delphi
5. Java Script

A dragon curve is any member of a family of self-similar fractal curves, which can be approximated by recursive methods such as Lindenmayer systems as a procedure in Pascal shows:

procedure Dragon(n,a,t:Integer; d,x,y: Double; var b: TBitmap);
  var a1, a2: integer;
begin
 if n 



<p>Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree angle. And a left dragon is a left followed by a right. The same you get also with Python and Turtle in maXbox:<br>
</p>

<pre class="brush:php;toolbar:false">Const DRAGFUNC =
  'def dragon(level=4, size=200, direction=45):   '+LF+
  '  if level:                                     '+LF+
  '      right(direction)                          '+LF+
  '      dragon(level-1, size/1.41421356237, 45)   '+LF+
  '      left(direction * 2)                       '+LF+
  '      dragon(level-1, size/1.41421356237, -45)  '+LF+
  '      right(direction)                          '+LF+
  '  else:                                         '+LF+
  '      forward(size)                             ';

function PyCodeDragonTurtle(imgpath, aAPIKey: string): string;
begin
  with TPythonEngine.Create(Nil) do begin
  //pythonhome:= 'C:\Users\User\AppData\Local\Programs\Python\Python312\';
  try
    loadDLL;
    autofinalize:= false;
    ExecString('from turtle import right,left,forward,speed, exitonclick,hideturtle');
    ExecStr(DRAGFUNC); 
    ExecStr('speed(0)');  
    //ExecStr('hideturtle()'); 
    ExecStr('dragon(6)');
    ExecStr('exitonclick()');
    //result:= (EvalStr('r.json()')); *)
  except
    raiseError;        
  finally      
    Free;
  end; 
 end;
end; 

The dragon curve is probably most commonly thought of as the shape that is generated from repeatedly folding a strip of paper in half.

Dragon as Pen.Color:= (p);

The script you get at:
Multilanguage Script

https://sourceforge.net/projects/maxbox/files/Examples/13_General/1320_dragon_curve_51_py.txt/download

with Depth = 9

Pen.Width:= 2; Pen.Color := cllime;

Turtle Sound

Try the sound that turtle with angle as amplitude and step as tone:

procedure DrawDragon2(step, adir: integer; len:real);
begin
  //myturtle:= TJvTurtle.create(self);
  with myturtle do begin
    if (step >-1) and (len >1) then begin
      len:= len /sqrt(2);
      Turn(45*adir);
        DrawDragon2(step-1, +1, len);
      Turn(-90*adir);
        DrawDragon2(step-1, -1, len);
      Turn(45*adir);
    end else      //*)
      moveforward(len )
  end;  
end;

JavaScript Embedded

The Microsoft Edge WebView2 control allows you to embed web technologies (HTML, CSS, and JavaScript) in your native apps. The WebView2 control uses Microsoft Edge as the rendering engine to display the web content in native apps.

<!-- DragonCurve.html -->


<script type="text/javascript">
function pDragon(cId) {
  // Plotting Dragon curves. 2/25/17 aev
  var n=document.getElementById('ord').value;
  var sc=document.getElementById('sci').value;
  var hsh=document.getElementById('hshi').value;
  var vsh=document.getElementById('vshi').value;
  var clr=document.getElementById('cli').value;
  var c=c1=c2=c2x=c2y=x=y=0, d=1, n=1<<n;
  var cvs=document.getElementById(cId);
  var ctx=cvs.getContext("2d");
  hsh=Number(hsh); vsh=Number(vsh);
  x=y=cvs.width/2;
  // Cleaning canvas, init plotting
  ctx.fillStyle="white"; ctx.fillRect(0,0,cvs.width,cvs.height);
  ctx.beginPath();
  for(i=0; i<=n;) {
    ctx.lineTo((x+hsh)*sc,(y+vsh)*sc);
    c1=c&1; c2=c&2;
    c2x=1*d; if(c2>0) {c2x=(-1)*d}; c2y=(-1)*c2x;
    if(c1>0) {y+=c2y} else {x+=c2x}
    i++; c+=i/(i&-i);
  }
  ctx.strokeStyle = clr;  ctx.stroke();
}
</script>


<p><b>Please input order, scale, x-shift, y-shift, color:></b></p>
<input id="ord" value="11" type="number" min="7" max="25" size="2">
<input id="sci" value="7.0" type="number" min="0.001" max="10" size="5">
<input id="hshi" value="-265" type="number" min="-50000" max="50000" size="6">
<input id="vshi" value="-260" type="number" min="-50000" max="50000" size="6">
<input id="cli" value="red" type="text" size="14">
<button onclick="pDragon('canvId')">Plot it!</button>
<h3 id="Dragon-curve">Dragon curve</h3>
<canvas id="canvId" width="640" height="640" style="border: 2px inset;"></canvas>

 

Modify and explore in EdgeView of maXbox5
The Script you find at:

the whole 5 languages script at

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