adding graphics to max/msp

You do need to edit the javascript code. Do you want dial functionality, or did you want the radius to scale as you shift-drag, say? (this is pretty trivial to do)

The variable you're interested in is vradius. You also need to know how the mouse has changed relative to its previous position so create a global variable called prev_w. (below)

var prev_w = [];

You'll need to tweak the onclick and ondrag methods.

For onclick, you should store the value of w into prev_w (so it's not blank, and also so if we click to jump we won't have a crazy scaling factor)

Ondrag needs to be slightly changed. This call doesn't have a shift parameter, but you can find the relevant looking one in the jsui dial's source code. It looks like this:

function ondrag(x,y,but,cmd,shift,capslock,option,ctrl) { // note the presence of shift, which is what we need

w = sketch.screentoworld(x,y);
// w[0] = x pos, w[1] = y pos

// Now find the distance between the two points
var distx = w[0]-prev_w[0];
var disty = w[1]-prev_w[1];

var distance = Math.sqrt(distx*distx + disty*disty); // Pythagorean distance
if (distx
vradius -= distance;
} else {
vardius += distance;
}

// At the end of this function, you should store w into prev_w:
prev_w = w;

This is my best guess at it (haven't tried this yet!)