Technique for debugging Three.js - javascript

I have a Three.js page that I'd like to update from r42 to r55. A fair amount of the API has changed in that time.
Some of these changes were straightforward, but now I'm stuck on some gnarly details of the JSONLoader, for which the format has changed from JavaScript to JSON and possibly other changes are causing it to fail. An undefined value is tripping up the API somewhere internally, and I can't tell what the issue is because the top few layers of the stack are in minified code.
What technique works best for getting the full source here? Are there source maps available?
I tried swapping the three.min.js file for Three.js, however the minified file contains many other files too. I don't like the idea of having to load all those files into my workspace and reference each of them just to debug a single issue for a minute.
Is there a single file that contains the non-minified equivalent of three.min.js? Is there another approach that would work just as well?
EDIT So I'm cloning the three.js repo to get the source files, and will end up with a bunch of HTML like this:
<script type="text/javascript" src="three.js/src/Three.js"></script>
<script type="text/javascript" src="three.js/src/core/Object3D.js"></script>
<script type="text/javascript" src="three.js/src/core/Geometry.js"></script>
...
The repo is ~200MB and is taking an age to clone. There's no way to do partial clones with Git, apparently.
There has to be an easier way!

Actually that is what I do when I want to debug my code. Swap out three.min.js and put in three.js. The minified version contains the same code.
The non-minified version of the file is under version control:
https://github.com/mrdoob/three.js/tree/master/build

use non-minified builds
look at the commented out debugging points already present in three.js (i.e. console.log)
'use strict' if not already
add more console.log/debugs

Related

Draw.io : How can I debug unminified js code?

I downloaded draw.io source files from the github repository and tried to make some minor changes to the import function, but all the sources are minified (especially app.min.js).
So my question is this: is there any way to debug the code with the unminified sources?
Also I tried to pass inside the query string the param dev=1, but it gives some errors and doesn't manage to load.
I already saw the post Draw.io — Is there non-minified source? but I don't know how to build draw.io.
If you know the function that you need to edit you can use https://unminify.com to reverse the spacing minification but the variable and function names will still be simplified making it difficult (but not impossible) to edit.
I've found, in my opinon, a strange solution.
I took build.xml file and replaced all the <jscomp> instructions with <concat> so the result file isn't a minification but just a merge of all source files.
This method works just fine and it solves my problem but i don't know if there is a simpler and more right method.

How do I install ReactJS locally?

I've tried reading over the "guide" on their website, and none of it makes sense to me. I thought it'd be the same thing as JQuery, but apparently I'm missing something.
I have this appended in my html document (where it's appropriate of course):
<script src="respond.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script src="https://unpkg.com/react#latest/dist/react.js"></script>
<script src="https://unpkg.com/react-dom#latest/dist/react-dom.js"></script>
<script src="https://unpkg.com/babel-standalone#6.15.0/babel.min.js"></script>
<script src="app.js"></script>
<script type="text/babel" src="app_2.js"></script>
As you might have guessed, I'm using Adobe Dreamweaver to develop my webpage.
That is what the first script element is for. The second being for JQuery.
After running an "example" for ReactJS with JSX, I found the three following script elements in the html document. That, to me, tells me that all I had to do in order to get it working is link those in as well.
Long story short: it didn't work. I tested it on Firefox and Chrome.
The thing I'm still scratching my head over is the error I receive when trying to view the remote files for the ReactJS-related files (on DW):
Not found: package "filename%version"
Where filename is the name of the JS file and version is the version (I'm assuming).
This only occurs for those files and not for JQuery. DW still let's me know that the file is remote and cannot be altered, but I get nothing for the other remote files.
What gives?
I was able to get it working after some scrambling, reading, and random attempts.
Turns out I was getting in my own way.
Because of the tutorial I was learning react from, I had assumed I was required to always create a react object and react-dom object.
After removing those two declarations from my js file, I was able to then see the expected results in my browser.
The only thing I can think of as to why those declarations would cause an issue is either because one of the files I import already does so (which has to happen as I don't declare the "React" or "React-dom" instances anymore but am still able to use them) or it is no longer required explicitly. The tutorial I went through was a bit dated.
I'm gonna have so much fun with this!

ClojureScript-Lib and my ClojureScript on same page

Let's assume I have a small web-application and want to use a third-party library that comes with an already compiled version of a ClojureScript.
As a user of that library I have to include that generated Javascript file in my HTML page.
<script src="/javascript/gen/lib.js" type="text/javascript">
So far so good. Everything works fine.
But since my web-application needs some frontend-magic, I wanted to include some ClojureScript of my own. So I wrote a couple of lines, compiled it to Javascript and added another line in the HTML head:
<script src="/javascript/gen/lib.js" type="text/javascript">
<script src="/javascript/gen/my-stuff.js" type="text/javascript">
This is, where it gets ugly. I get this error in the javascript console:
Error: Namespace "goog.debug.Error" already declared.
After googling that error, I get multiple pages, that state, that I can not use multiple Google Closure Compiled things on one page. See SO: Multiple ClojureScript files on same page
So, how do I tackle that situation? On one hand I have an already Google Closure compiled lib and on the other hand my ClojureScript stuff. How do I get one (or two) compiled Javascript files out of this?
Would it be easier, if that third-party lib would provide a non-compiled ClojureScript version?
Yes, it would be easier if the third-party library would provide a non-compiled ClojureScript version. Then you would require it and use it from your code and compile everything together. The ClojureScript compiler with require each dependency once (even the shared dependencies) and the Google Closure compiler would do its optimization pass over all the code.
Try to find the library in Clojars or package it as a jar to consume it from your existing ClojureScript setup. (If the library is open source, give us a link and we'll help you out)

Why using jquery map?

Why using jquery.min.map if:
jquery = 242 ko
jquery.min + jquery.min.map = 83 + 125 = 208 ko (the map is even greater than the library)
And if we remove the comments, we will get a small jquery that could be easier to read (and to debug).
So, why using the map if it will only add more than 100 ko and an extra request?
What is the best practice?
Source maps are loaded only when the developer tools are active. Browsers won't load them for application's users.
Edit: It should be mentioned that there are 2 types of source maps. One which is an external file and there is a link to it in the actual file and another one which is embedded in the main file. Browsers actually have to load the entire file (i.e. including the embedded source map) for the second type.
Check https://www.html5rocks.com/en/tutorials/developertools/sourcemaps/ for more information.
That's called a source map. This answer goes into detail about what they are, how they work, and why you would want to use it.
EDIT
Extracted answer from the above SO link for posterity. Answered by #aaronfrost
The .map files are for js and css files that have been minified. They are called SourceMaps. When you minify a file, like the angular.js file, it takes thousands of lines of pretty code and turns it into only a few lines of ugly code. Hopefully, when you are shipping your code to production, you are using the minified code instead of the full, unminified version. When your app is in production, and has an error, the sourcemap will help take your ugly file, and will allow you to see the original version of the code. If you didn't have the sourcemap, then any error would seem cryptic at best.
Same for CSS files. Once you take a SASS or LESS file and compile it to CSS, it looks nothing like it's original form. If you enable sourcemaps, then you can see the original state of the file, instead of the modified state.
What is it for?
To de-reference uglified code
How can a developer use it?
You use it for debugging a production app. In development mode you can use the full version of Angular. In production, you would use the minified version.
Should I care about creating a js.map file?
If you care about being able to debug production code easier, then yes, you should do it.
How does it get created?
It is created at build time. There are build tools that can build your .map file for you as it does other files. https://github.com/gruntjs/grunt-contrib-uglify/issues/71

Can I use CoffeeScript to combine other js files?

I'm wondering if I can use CoffeeScript to include other standard JS files (as a simple way to do some combining of files).
I have a client-side minification tool I'm using (an app called Live Reload) which is working just fine.
<!-- Some jQuery plugins I'm using. -->
<script src="/js/libs/some-plugin.js"></script>
<script src="/js/libs/another-plugin.js"></script>
<!-- The output of my /js/script.coffee file: -->
<script src="/js/script.js"></script>
What I'd like to do, is just combine those plugins into output of my coffeescript file. I've looked high and low and I've only seen articles on server methods for this as well as a lot of articles on things like requirejs.org. I'm not trying to do anything that complex- I just want to get rid of a couple round trips for js files I know I'm never going to touch.
Does CoffeeScript have an "include" function to speak of?
There are ways you can achieve this by creating a more complex Cakefile, in which you will read the contents of js-files and append them with CS compiler output than write it into the single target js file. You can even create a fake global require function which will mimic its behaviour in the bundled file.
If you were looking for a standard tool or at least an approach to that problem, unfortunately, since CS is very young, there's none yet. There are some attempts though: https://github.com/jashkenas/coffeescript/wiki/%5BIntegrations%5D-Build-Tools.
I'm currently working on such a tool myself and am planning to publish it within a month. I'll post back then.
Basically, the answer seems to be no. This is not something CoffeeScript is capable of.

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