bijection / g9 Goto Github PK

I'll take the example code from "using Max and Min to limit a point's range of motion" as a starting point:

 var initial = {
    x1: -100,
    x2: 0,
    x3: 100,
}

function render(data, ctx){
    var m = Math.max(Math.min(data.x2, data.x3 - 20), data.x1 + 20)
    ctx.point(m,0, {affects: ['x2']})
    ctx.point(data.x2,20, {affects: ['x2']})
    ctx.point(data.x1,0, {fill: 'red'})
    ctx.point(data.x3,0, {fill: 'red'})
}

When I drag point x1 or x3, there's nothing stopping me from dragging one point beyond the other.

That can be fixed by repeating the trick used for x2:

    var mMin = Math.min(data.x1, data.x3 - 40)
    var mMax = Math.max(data.x1 + 40, data.x3)
    var m = Math.max(Math.min(data.x2, mMax - 20), mMin + 20)
    ctx.point(m,0, {affects: ['x2']})
    ctx.point(data.x2,20, {affects: ['x2']})
    ctx.point(mMin,0, { affects: ['x1'], fill: 'red'})
    ctx.point(mMax,0, { affects: ['x3'], fill: 'red'})

Now x1 and x3 can't get closer than 40 pixels and stop when dragged into each other. Great! But then I thought: well, what would be really cool is if x1 and x3 would push each other when dragged into each other. Is there a way to do this?

The problem, as I see it, is that in order for this to work, the values of x1 and x3 would have to be mutually dependent on each other: if I drag x1 into x3, then the value x3 should depend on x1, but if I drag x3 into x1, the value of x1 should depend on x3. And for that to work I need to know which of the points is being dragged, but I don't see a way to check for that in the documentation. But maybe there's another trick and I just don't properly think in terms of constraint based programming yet?

Hi there,

I really love the g9.js demos! I think they convey how gradients work in such a nice and intuitive manner.

Just for fun I was playing with the idea of running a Torch-like library in the browser. I ported over most of the g9 code to python and ran it with AD (as opposed to finite-differences) -> https://srush.github.io/g9py/ . Not sure why this is better, but it might let you run models with tons of parameters. Let me know if this is okay.

Cheers!
Sasha

Hi,

When I do an 'insertInto' call, the SVG which is created has its viewbox automatically set to some drawing size and offset. If I am rendering into a fixed size Div tag, how to I ensure that the resulting drawing is not arbitrarily re-scaled?

Thanks,
Forrest

Hi all, thanks for this awesome library! May I ask what the license is for using it?