SpaceCurve

I hope that almost all of this is self-explanatory.
1. Entering formulas
The three wide fields immediately below the main window
are the components of the parametrization.

The formula parser knows the following functions:
	sin		cos		tan
	sinh		cosh		tanh
	arcsin		arccos		arctan
	arcsinh		arccosh		arctanh
	exp		ln
and the following binary operations, with their usual precedence:
	+	-	*	/	^
You can refer to the constants
	pi	and 	e
by name in your formulas.  Use 't' for your parameter; other variable 
names will be treated as if they are zero.
2. Changing the parameter
The two fields showing '-2' and '2' in the picture below hold the 
minimum and maximum values of 't', respectively.  The round,
horizontal slider immediately below them changes the current value
of the parameter.  The round button next to the 'maximum t' field
lets you mark a point to serve as the basepoint for the arc-length
calculation.
3.  Readouts
'K' and 'T' are curvature and torsion, respectively.  's' is arc-length
between the current (white) point and the marked (red) point.  The 's'
field may be greyed out if arc-length integrals didn't seem to be 
converging.
4.  Adjusting the view
You can click and drag in the main window to rotate the view, and you
can Control-Click-and-drag to zoom in and out.  The small slider on 
the right controls the size of any decorations you're currently drawing.

The slider at the the very bottom of the screen can be used to increase
the number of points used to draw your curve.  If your drawing doesn't
look smooth, drag this to the right.