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Re:D3.compose – compose reusable charts and components with ... by forrestthewoods on Monday December 07, 2015 @10:56AM (#10690162)
I swear many people would be better off just manually generating paths on their own. It's not difficult.

D3 is pretty awesome and all but it is NOT a charting library. It's a data binding framework. It adds several layers of incredibly hard to follow abstraction.

It's super duper cool when it does exactly what you want and all you desire is to drop your in your data. A+++ would recommend. But if you want to do something slightly different it's a huge pain in the ass. At the end of the day it's just a handful of SVG primitives. Draw them yourself and move on with your day. I promise you it's easier.

Re:D3.compose – compose reusable charts and components with ... by timruffles on Monday December 07, 2015 @11:59AM (#10690686)
Wha? Yes, D3 is definitely not a charting library - because it's a data-focused, thin wrapper over the DOM & SVG APIs. It's designed from the group up to "let you do something slightly different": that's the point. It's the low-level primitives you'd otherwise reinvent.

Your experience is totally different from everyone on every team I've used D3 with, and all the people I've taught D3. I can understand "D3 does too little", but "D3 does too much" is just weird.

Re:D3.compose – compose reusable charts and components with ... by catpolice on Monday December 07, 2015 @12:47PM (#10691100)
Hmm, here's my experience:

What I've needed from D3 is the math-y bits: calculating layouts, paths, etc. What I don't need (or want) is for it to ever touch the DOM.

But that's what it wants to do most. D3 is sort of the best of the jQuery-inspired "select and mutate" generation - it does data binding in a way that really makes sense as long as you let it handle DOM operations.

But following React, there's been a pretty big movement away from procedural DOM manipulation and toward the declarative re-rendery "DOM as a pure function of state" approach. In that case, letting D3 mess with the DOM (especially in the way that it does, where complex links between DOM and data are maintained in the background) is bad news.

If you already have a way of getting elements in and out of the DOM and keeping their state aligned with the data that you like better than the select-and-mutate model, a lot of what D3 does seems unnecessary or introduces problematic interference. React and D3, for instance, tend to not play very nice without a lot of effort.

I've had projects where programmers lean on D3 because that's the way they've learned to get SVG elements into the DOM - they'll take an example they've found somewhere that mostly only uses simple shapes, modify it a little bit to do what they want and ask me for help adding that visualization into another project. Sometimes in these cases, D3 isn't getting used for much except for "insert an svg element with these attributes for every node in this data structure", in which case it's total overkill, and I end up stripping it out entirely. I sometimes end up keeping it around for things (I'm probably not going to write my own Reingold-Tilford tree layout algorithm), but often in these cases I have to do extra work to keep it from conflicting with other things.

Re:D3.compose – compose reusable charts and components with ... by jcheng on Monday December 07, 2015 @01:38PM (#10691532)
I had come to the same conclusion as I'm very sympathetic to the React mindset, and thought that combining the d3 "math-y bits" with React as a rendering engine might be the very best of both worlds.

But the one thing that I couldn't find a good solution to, was transitions/animations as data changes. Support for transitions in d3 is quite impressive (often just calling .transition() on your selection) and I couldn't find nearly as nice a solution with React, though chenglou[0] seems to be making continuous progress.

[0] https://github.com/chenglou

Re:D3.compose – compose reusable charts and components with ... by snappy173 on Monday December 07, 2015 @05:44PM (#10693368)
I just stuck with d3, and used the react lifecycle methods to trigger redraws and such.

http://bl.ocks.org/cpapazian/6228888157c39be85e9c

The D3Component wrapper lets you put a d3-style reusable component inside of a react dom tree, using react props to pass parameters and event handlers to the d3 chart.

Re:D3.compose – compose reusable charts and components with ... by rjayatilleka on Monday December 07, 2015 @04:31PM (#10692868)
That's a very fair judgement, but it's also something the d3 team knows about. D3 4.0 is breaking d3 into a bunch of reusable components. The exact use case you mentioned, getting the path/layout data so React or anoth DOM manipulation library can be used, is supported by d3-shape, which just can out recently. Tree diagrams are still in progress, but various curves and pie charts are already implemented.
Re:D3.compose – compose reusable charts and components with ... by andreaferretti on Monday December 07, 2015 @05:24PM (#10693216)
This is exactly the use case I ran into most often, and I have designed a small library precisely to do these computations without touching the DOM. If you want to have a look, it is on https://www.github.com/andreaferretti/paths-js
Re:D3.compose – compose reusable charts and components with ... by timruffles on Tuesday December 08, 2015 @11:33AM (#10697382)
Just to say, D3 is entirely the 're-rendery "DOM as a pure function of state"' approach. `el.__data__` is just optimisation (if you're only using d3). You should be able to `setInterval(yourD3Code, 16)` if you're writing idiomatic d3.
Re:D3.compose – compose reusable charts and components with ... by purpleparakeet on Monday December 07, 2015 @01:11PM (#10691296)
FYI, D3 4.0 is just around the corner and breaks the library into different components so you can just import the ones you need.
Re:D3.compose – compose reusable charts and components with ... by jwr on Monday December 07, 2015 @11:21AM (#10690362)
I wondered if I was the only one who thought that way — apparently not. I also found D3 to be very inflexible, with abstractions doing strange things behind your back. In general, a lot of "magic" was happening behind the scenes.

I mostly write in ClojureScript, so the data binding wasn't that attractive — I can do all of that work better anyway.

I guess what I'm looking for is a library with graphics/charting primitives written in ClojureScript, possibly using React. Hmm.

Re:D3.compose – compose reusable charts and components with ... by krebby on Monday December 07, 2015 @11:35AM (#10690483)
The next version of D3 will be modular, with the different parts broken out into separate packages (i.e. shape utils separate from databinding utils). Currently I'm using D3 piecemeal with React with a good deal of success.
Re:D3.compose – compose reusable charts and components with ... by yashap on Monday December 07, 2015 @03:20PM (#10692383)
Disagree. Like any framework or medium-to-big library, D3 does take some time to learn, but totally pays off once you learn it. If you're just doing a single viz, then sure, rolling your own is ok. But if you're doing lots, and especially if they need to be interactive, I'd strongly advise against reinventing the wheel.

I also have not found it too hard to step outside of/modify the online examples, though I guess it depends on the particular viz you're trying to create.

Re:D3.compose – compose reusable charts and components with ... by mizzao on Monday December 07, 2015 @12:39PM (#10691025)
I've had the complete opposite experience with D3. It adds one layer of abstraction (data binding) that is a little hard to understand, but pays off reams once you "get" it.

It doesn't do anything if you just desire to drop in your data - you need to build everything from scratch. On the other hand, if you start with good code or a good example and want to do something slightly different, it's very easy to modify to do what you want.

The amount of code it would take to "do everything yourself" that D3 does would be an order of magnitude more.

Re:D3.compose – compose reusable charts and components with ... by SonicSoul on Monday December 07, 2015 @11:45AM (#10690559)
Can you elaborate on "manually generating paths"?
Re:D3.compose – compose reusable charts and components with ... by forrestthewoods on Monday December 07, 2015 @12:06PM (#10690743)
The end result is an <svg> element with a bunch of with a bunch of <path> <line> <rect> children. Sometimes you can wrangle D3 to generate the <path>s you want. Sometimes it's easier to more directly make them yourself.
Re:D3.compose – compose reusable charts and components with ... by ZoeZoeBee on Monday December 07, 2015 @12:07PM (#10690753)
You can use SVG to draw a line between points, and set the interpolation