Typo in smooth_heaviside?

[Yanksi]

In smooth_heaviside.glsl, $t$ is described as:

//   t  control steepness of step function: --> 0 more linear, --> inf more like
//     Heaviside function (piecewise constant function x<0--> -1 , x>0 --> 1)

However, when I was trying to plot the function, it seems that the boundary point should be 0.5 instead of 0.

[alecjacobson]

ack. This is frustrating. Thanks for point it out. For now, I've simply fixed the comment to correctly describe what it's doing (despite being wrong). This way existing programs will not be broken.