Using Mapbox GL JS 0.39.1, I set a filter on my layer:
map.setFilter('myLayer', ['!=', 'myKey', 'myValue'])
I cannot find a way to remove the filter. I would have thought there would be a map.removeFilter... function but have found nothing in the docs or in web searches. I could apply a fake filter (>'') so that it always matches but that seems inefficient. Surely there is a way to remove a filter.
EDIT: I have found that using the following code will achieve what I am trying to accomplish. Not sure if this is the recommended approach.
map.setFilter('myLayer');
The docs were just updated, personally I would recommend using
map.setFilter('myLayer', null)
as it's more explicit and in my opinion makes the code more readable. Though your approach of just map.setFilter('myLayer'); is also acceptable.
Related
babel-plugin-dev-expression can be used to transform __DEV__ to process.env.NODE_ENV !== 'production'.
But is there a Babel transform plugin to convert other "code fence" symbols to process.env expressions?
For example, I'd like to be able to transform __DEBUG__ to process.env.DEBUG.
Before I try to write a plugin myself, does anyone know of one that already exists? Google is not turning up anything, but I'm sure it must exist as I won't be the first person who's wanted this.
I found a plugin that does this: babel-plugin-transform-replace-expressions
Initially I'd thought it was just doing a string-based search and replace, but actually it's more sophisticated than that, so it fulfils the use case.
I'm writing MapBox vector tiles using geotrellis vectorpipe.
see here for the basic flow: https://geotrellis.github.io/vectorpipe/usage.html
Typically GeoJson Features can have an id field, so that Features can be rolled up into FeatureCollections. I need to make use of this field, but vectorpipe doesn't (natively) have this capability.
This is the Feature type used, and you can see it only has space for 1) a Geometry and 2) a data object D (which ends up populating properties in the output). There is no spot for an id.
https://geotrellis.github.io/scaladocs/latest/index.html#geotrellis.vector.Feature
Upstream there's a method called writeFeatureJsonWithID() that does let you inject an id field into a Feature when writing GeoJson.
https://github.com/locationtech/geotrellis/blob/master/vector/src/main/scala/geotrellis/vector/io/json/FeatureFormats.scala#L41-L49
My question is this:
I have worked through the vectorpipe code (https://github.com/geotrellis/vectorpipe), and I can't figure out if/where the data ever exists as GeoJson in a way where I can override and inject the id, maybe using the writeFeatureJsonWithID() or something I write explicitly. A lot of conversions are implicit, but it also may never explicitly sit as json.
Any ideas for how to get an id field in the final GeoJson written to vector tiles?
EDIT
Right now I think the trick is going to be finding a way to override .unfeature() method here:
https://github.com/locationtech/geotrellis/blob/master/vectortile/src/main/scala/geotrellis/vectortile/Layer.scala
The problem is that the internal.vector_tile.Tile is private, so I can construct it without forking the project.
Ended up having to fork geotrellis, hard-code a metadata => id function in Layer.unfeature() and compile locally to include in my project. Not ideal, but it works fine.
Also opened an issue here: https://github.com/locationtech/geotrellis/issues/2884
I noticed that hyperHTML preserves references I make to elements:
let div = document.createElement("div");
div.textContent = "Before Update";
hyperHTML.bind(document.body)`static1 - ${div} - static2`;
div.textContent = "After Update";
Above will produce a page that says:
static1 - After Update - static2
It is my understanding that hyperHTML ultimately clones an HTML <tempate> element to render the final output. However, don't you typical lose references when cloning an HTML template (like the variable "div" in the example above)?
Therefore, on the initial render, does hyperHTML somehow replace cloned elements with their originals after cloning the HTML template?
Here's how I think it works:
Create an HTML Template of the original template literal while
replacing all interpolations with comments.
Clone the html template with comments left in.
Make elements or document fragments out of each interpolation originally recieved
Replace each comment in the clone with its processed interpolation.
Is this correct?
I am not sure what is the question here, but there is a documentation page, and various examples too to understand how to use hyperHTML, which is not exactly in the way you are using it.
In fact, there's no need to have any reference there because hyperHTML is declarative, so you'd rather write:
function update(text) {
var render = hyperHTML.bind(document.body);
render`static1 - <div>${text}</div> - static2`;
}
and call update("any text") any time you need.
Here's how I think it works ... Is this correct?
No, it's not. hyperHTML doesn't clone anything the way you described, it associates once per unique template tag a sanitized version to the output and finds out all interpolated holes in it.
The part of the library that does this is called domtagger, and the mapping per template literal is based on the standard fact that these are unique per scope:
const templates = [];
function addTemplate(template, value) {
templates.push(template);
return template.join(value);
}
function asTemplate(value) {
return addTemplate`number ${value}!`;
}
asTemplate(1);
asTemplate(2);
asTemplate(Math.random());
templates[0] === templates[1]; // true
templates[1] === templates[2]; // true
// it is always the same template object!
After that, any other element using once that very same tag template will have a clone of that fragment with a map to find holes once and some complex logic to avoid replacing anything that's already known, being that text, attributes, events, or any other kind of node.
hyperHTML never removes comments, it uses these as pin and then uses domdiff to eventually update nodes related to these pins whenever there's a need to update anything.
Domdiff is a vDOM-less implementation of the petit-dom algorithm, which in turns is based on E.W Myers' "An O(ND) Difference Algorithm and Its Variations" paper.
Whenever you have DOM nodes in the holes, hyperHTML understand that and fill these holes with those nodes. If you pass repeatedly the same node, hyperHTML won't do anything 'cause it's full of algorithm and smart decisions, all described in the documentation, to obtain best performance out of its abstraction.
All these things, and much more, normalized for any browser out there, makes hyperHTML weight roughly 7K once minified and gzipped, bit it also offers:
Custom Elements like hooks through onconnected/disconnected listeners
lightweight components through hyperHTML.Component
SVG manipulation as content or via wire
easy Custom Elements definition through HyperHTMLElement class
As summary, if you need these simplifications and you don't want to reinvent the wheel, I suggest you give it a better try.
If you instead are just trying to understand how it works, there's no need to assume anything because the project is fully open source.
So far, all I've read from your questions here and there, is that you just believe to understand how it works so I hope in this reply I've put together all the missing pieces you need to fully understand it.
Do you want to write your own lit/hyperHTML library? Go ahead, feel free to use the domtagger or the domdiff library too, few others are already doing the same.
I'm working on a script to convert a Simulink library to a plain model, meaning it can be simulated, it does not auto-lock etc.
Is there a way to do this with code aside from basically copy-pasting every single block into a new model? And if it isn't, what is the most efficient way to do the "copy-paste".
I was not able to find any clues as how to approach this problem here, or on Google, or on the official documentation or on the MathWorks forum so I'm at a loss on how to proceed.
Thank you in advance!
I don't think it's possible to convert a library to a model, but you can programmatically add library blocks to models like so:
sys = 'testModel';
new_system(sys);
open_system(sys);
add_block('Simulink/Sources/Sine Wave', [sys, '/MySineWave']);
save_system(sys);
close_system(sys);
sim(sys);
You could even use the find_system command to list all the blocks in a library and then loop through them all and create a new model for each using the above code.
I was just curious to know if it's by any means possible to add a sort functionality to the default find action of a model without overriding the same in the controller ?
We do have beforeCreate and afterCreate features in the models which is quite useful in many cases. Similarly beforeFetch or something like that, if exists can be really useful when we want some pre/post processing on the result set while doing a get request.
An example of this would be: localhost:1337/user?sort=id desc