Programming turtle graphics: Difference between revisions

Revision as of 10:31, 21 December 2008

There is a predefined turtle object t. Therefore, all commands start with t, like t.fd(100);

t.forward(len); or t.fd(len);
t.back(len); or t.bk(len);
t.right(angle); or t.rt(angle); ([math]\displaystyle{ 0\leq angle \leq 360 }[/math])
t.left(angle); or t.lt(angle);
t.penUp(); or t.pu();
t.penDown(); or t.pd();
t.clearScreen(); or t.cs();
t.clean();
t.setPos(x,y);
t.home();
t.hideTurtle(); or t.ht();
t.showTurtle(); or t.st();
t.setPenSize(size); (size: number)
t.setPenColor(col); (col: colorString, e.g. 'red' or '#ff0000')

@@ Line 24: / Line 24: @@
 <script type="text/javascript" src="http://jsxgraph.uni-bayreuth.de/distrib/jsxturtle.js"></script>
 <form><textarea id="input" rows=3 cols=35 wrap="off" style="width:600px;">
+t.fd(100);
 </textarea><br />
 <input type="button" value="run" onClick="run()">
+<input type="button" value="clear" onClick="clear()">
+<input type="button" value="clear log" onClick="clearlog()">
 </form>
 </html>
@@ Line 36: / Line 39: @@
 function run() {
    brd.suspendUpdate();
-   eval($('input').value);
+  var code = $('input').value;
+   eval(code);
+  $('logwindow').innerHTML += code+'\n';
+  $('input').value = '';
    brd.unsuspendUpdate();
+}
+function clear() {
+  t.cs();
+  $('input').value = 't.fd(100);';
+}
+function clearlog() {
+  $('output').innerHTML = '';
 }
 </script>
 </html>
 ===Log window===
-<source lang="javascript">
+<html>
-</source>
+<pre id="logwindow" class="javascript javascript" style="font-family:monospace;">&nbsp;</pre>
+</pre>
+</html>