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Mapbox GL JS line animation

I am working with ~150,000 polylines that span North America. Across all the lines I'd like to draw/animate from the start to the end of each line. I started down the road of adding vertices to an array and updating a Mapbox source like this example. This was not feasible given the size of the entire dataset. In geojson form it's about 800mb and manipulating this in the browser seemed unreasonable.
As an alternate approach, I've broken each polyline into equally sized segments of 10km in length. I added an attribute on each segment which represents its percent distance from the start. I created an interval below that triggers a setFilter event, filtering segments based in the percent from start.
currentLinPos=0;
lineInterval=setInterval(function(){
currentLinPos+=.01;
if(currentLinPos>0.9999){
currentLinPos=0
}
map.setFilter('lines',['<','linePrc',currentLinPos])
}, 250);
Even when working with a small subset of the data, performance choppy and lags. I expected a better result from Mapbox GL but perhaps I need to rethink my data structure or approach entirely. Or would using something like DECK.GL be far superior here?

Increase Linewidth on zoom THREE.js

I try to process dynamic 2d rainfields (comparable to this, just that I process the data dynamically and animate it).
Until now I found that the best fitting solution for my project is creating horizontal LineSegments, so I can process the data set line by line and give each LineSegment a color. I store everything I need in a BufferGeometry.
Now my problem is
that when I implement a zoom by simply reducing the z-index of the camera, the spaces between those lines become visible, because the lines dont become thicker.
I read that the linewidth-parameter of a LineSegment object is inaccessible on Windows so is there any other way I could try?

How to get the same node positions in d3's force layout graph

I would like to create a force directed graph, but i need it to stay the same every time it is generated (with the same data).
Is there any way to do this using d3.js?
UPDATE:
I found working solution, which is based on using seeded random number generator
// set the random seed
Math.seedrandom('mySeed');

You could by modifying D3's force layout, or by creating your own layout based on it. There are at least 3 places where randomness (Math.Random) is used in the positioning of nodes (there may be more, given the force layout references other code). You would have to eliminate all randomness in order to get the graph to display in the same way each time:
https://github.com/mbostock/d3/blob/master/src/layout/force.js
However, this would hamper how the layout works – it's using randomness to sort itself out into a legible diagram quickly. If your number of nodes is small, then it probably wouldn't be an issue, but a large number of nodes could just end up a tangle.

D3.js scattergraph with large (>500,000) points? Clustering?

I'm looking at plotting a scatterplot with a large number of points (500,000 and upwards).
Currently, we're doing this in Python with Matplotlib. It plots the points, and it provides controls to pan and zoom. I don't believe it provides any clustering or points, it just plots them all - doesn't make much sense at the zoomed out view, I suppose, but you can zoom in and they're all there.
I was looking at doing the chart in JavaScript, to make it a bit easier to distribute. I was looking at D3.js, to see if something similar is feasible there. I did find this example of a basic scatterplot:
http://bl.ocks.org/mbostock/3887118
Firstly, would you be able to plot that number of points? (500,000 and upwards) I was under the impression you couldn't due to the overhead of all the DOM objects? Are there ways around this?
Secondly, is there any kind of clustering available, either a library or even just an example of this being done in D3.js?
Thirdly, if anybody knows any good examples of pan/zoom functionality and clustering, or even just a packaged JS library that handles it, that would be awesome.
Fourth, it would be also nice to have click handlers for each point - and to display some text either in a overlay, or even just in a separate window. Any thoughts on this?

Can you draw half a million points with D3? Sure, but not with SVG. You'll have to use canvas (here's a simple example with 10,000 points that includes brush-based selection: http://bl.ocks.org/emeeks/306e64e0d687a4374bcd) and that means that you no longer have individual elements to assign click handlers to. You will not be able to render half a million points with SVG, because all those DOM elements will choke your interface, as you mentioned.
D3 does include quadtree support that can be leveraged for clustering. It's in use in the above example to speed up search but you could use it to nest elements in proximity at certain scales.
Ultimately, your choices are:
1) Some other library/custom implementation that renders in canvas and polls the mouse position to give you the data element rendered at that point.
2) A sophisticated custom D3 approach that nests elements in proximity and only renders SVG elements appropriate at the zoom level and canvas position (pan) you're at.

Yes, D3.js can be made to work with million scale data with two things:
pre-rendering on the server side. For more see here: https://mango-is.com/blog/engineering/pre-render-d3-js-charts-at-server-side/
By aggregating (or clustering) part of the data so that user can interact and expand the graph if need be. For this use collapsible nodes if you can (http://bl.ocks.org/mbostock/1062288).
Also avoid using force layout. It takes time to settle and converge to a stable positioning.
For clustering libraries, I would pick one up off the shelf. I would choose the scikits library from python, there are many in JavaScript but they are not very robust as they mostly cover k-means or hierarchical clustering. I would precalculate the coordinates using scikits by clustering and then render it using D3.
D3 handles Pan and zoom. Again click handlers and text display are available in D3. (http://bl.ocks.org/robschmuecker/7880033)

concept for creating a small game using sheetengine

I am creating a small isometric online game and would like to use the sheetengine.
Here is my basic idea:
create a scene of the size approx 4100x3000
creating 75x45 basesheets (since the World is 75x45 fixed and wont increase)
To place some objects on the map I use the class Sheet (I will only change the size and the position of the sheets after placing them)
For Zoom In/Out I actually redraw the whole scene - so I destroy all the basesheets and then place them from new in a bigger size - as for the Sheets ... I'm trying to change their size and their position
For moving the map I'm using the method scene.setCenter - since the scene is already of that huge size, I don't have to redraw the map after the translation
My questions:
How can I change the position and the size of the sheet after placing them? I know that using the SheetObject you can do all that, but I will have a huge amount of objects placed and the calculation time is taking to long with SheetObjects. That's why I'm not using that class... An object of the "class" Sheet has a property
sheet.data.translationx
I coudl also manipulate this and thsi works, but there must be method and I couldn't find it
Is there a better way of handling big scenes with sheetengine? I mean creating a scene that big is definitely not a good Idea. But if I make it smaller, I will not see the whole world after a translation - so how could I handle it differently?