This thread is for sharing my learnings and war stories from the LDraw web-rendering project buildinginstructions.js.
You can see how it evolves on BrickHub.org.

Here is a current example of how it renders a LEGO model:



It was not always like this. While there are at least two other web renderers that I know of, I still decided to start this project from scratch. This way I would get practical experience with the technologies involved (WebGL, Three.js, GLSL, etc.), and focus on having performance in mind from the very beginning. While the project itself hopefully ends up being of practical use for many, my goal with this thread is to share my experiences, wins and losses, and perhaps even get some good feedback to help drive the project forward.

The project started in July 2018 with the first breakthrough being in August 1. Back then I had finished an MPV of the .ldr parser while trying to adhere to the Three.js best practices for building a Loader. By modifying one of the Three.js sample files, I was able to get it to render:



As you can see, there were some massive BFC issues, but that was alright for a start. The important part was to get started and get something, anything really, up and running.
My top 3 takeaways from this early stage are:

- Ignore everything that is not absolutely needed in order to get started. This includes conditional lines, quads, BFC, colors, metadata, viewport clipping, etc, etc. While it is important to do things right, the proof of concept both gave me something tangible and came with a morale boost.

- Three.js and the LDraw file format work well together from the perspective of placing things in 3D. It is obvious that James Jessiman knew what he was doing when designing the specification.

- Depending on your approach of design, BFC can be very difficult to get right. There is psudocode in the spec, but unfortunately it did not fit into the data models I had chosen. The pseudocode assumes a single pass of computing both BFC information and triangle wrapping, while my code handles the BFC computation in a separate initial step that creates reusable components.

That is all for the first post. I will try to keep this thread alive with more war stories.

I'm working on a rendering application which requires very accurate models of all LEGO parts.
Naturally the LDraw library is a first stop for me, but I am running into some curious cases of lack of detail even in very common parts like 2xN bricks.
If you look at the underside of a real (modern) 2 x 4 brick for example, you will see a number of small supports, as well as divots where the studs stick out. However, such details are not present in even high resolution LDraw models.

I think it's fair enough if LDraw has some sort of philosophy that the part authors don't worry too much about this sort of detail. But I was just wondering if I was missing anything, or if there was a way to access more detailed part files, especially for very common elements such as these.

Thanks!

Sorry if I'm missing something obvious, guys. I'm now fully-converted to LDCad and loving it, but now that I've completed my first serious model using it (1400+ pieces) I can't seem to find an easy method to get a listing of all the parts used in it. I tried BrickUtils from years ago but it no longer appears to run and I can't quite follow all of the discussion about Rebrickable providing a parts list. Is there no parts list file export directly from LDCad?

Thanks again for all the great work and help!

Hallo community,

I designed an escape pod for my USC MF and wanted to save it in an proper building instruction. So I´m an bloody beginner with MLCad. I send a request to LEGO, about the used color palette. I received this list:

Quote:154 - New Dark Red
21 - Bright Red
41 - Tr. Red
1 - White
42 - Tr. Light Blue
322 - Medium Azur
23 - Bright Blue
102 - Medium Blue
140 - Earth Blue
24 - Bright Yellow
26 - Black
48 - Tr. Green
28 - Dark Green
330 - Olive Green
106 - Bright Orange
194 - Medium Stone Grey
199 - Dark Stone Grey
138 - Sand Yellow
05 - Brick Yellow
192 - Reddish Brown
312 - Medium Nougat
315 - Silver Metallic

Studio is a nice LEGO CAD tool, but current version (2.0.1(39)) lacks flexible parts. Fortunately, with some tweaks (and a few caveats), it is possible to use LDCad flexible parts in Studio.

If you created your model with Studio, you need to

• export it as LDraw
  
• open the exported model with LDCad
  
• add the flex parts using the guidelines that follow.
  
• reload the LDraw model in Studio.
  

• the fallback is made with segment parts present in the LDraw library of Studio
  
• The segment parts are not scaled: Studio is not able to scale parts.
  

Hi

I know this is an unusual  request, but could you please make a ball bearing part that fits in the hole of a Technic brick and the inner diameter fits to a Train metal axle (part x1687).

I need this to do instructions to train boogies that use these ball bearings.

Dimensions: 2x5x2.5mm



Thanks
Knud

Hello LDRAW people

hi guys i was wondering if there its any command or option that lpub can show you the sub model that you will be building as it was the PLI.

this is an example i do inserting an image of the sub model.




And also if there is any way to ask to render lpub a final image of the model. some times when i finish a building instruction is inside a sub model and i dont get a final render of the model in the last page. what im doing now is a render and add it as a image.

Hi,

I have the following problem:     

On the page is enough space for the model but it's only rendered in this small area. I have no idea how to fix this and I'm absolute beginner. I use LDGLite as a render and LPUB3D on Mac OS 

I think my code looks rather normal (not everything just until the step where it looks wrong):

Today i will be presenting a quick review of web lic. This application is like lpub but a web version of it its the evolution of licreator. As you know as its web version its probably slower than running on your local pc. but its works. its still on beta stage and every update its being published every time you login the web page.

URL: http://bugeyedmonkeys.com/lic/

Github: https://github.com/remig/web_lic

Main Features:

Web Lic is a free, open source web browser based application for creating and editing LEGO instruction books

Auto layout: Automatically layout the steps of your instruction book to nicely fill each page. Easily add a title page and an inventory page to list the parts in the model.

Rich, WYSIWYG UI editor: A fully interactive preview window makes it easy to customize the layout of your instruction book. Add new pages, steps or callouts with just a few mouse clicks. Quickly navigate through instruction books of any size.

Import and Export: Lic can import any LDraw-based model, which is supported by most LEGO model editors. Export your final instruction book as high resolution, print-quality images or PDF, or as small-sized images suitable for sharing online.


This application uses a private building instructions file format. you import your ldr file and its converted to a no human eye readable. Also it uses hi cpu and hi memory on the web browser.


when you open the ldraw file, it ask you if you want an auto arrange steps then it starts building the document.




as you can see you have a Template you can set and its apply to all the rest of the document. you can chang callout background. borders. layout etc. also you can chenge size of the pages background colors etc.



this is an example of an aligator. what i only did was open the file and it auto arranges several steps on the page if you dont want con work much. Also what i did was to modify the default look and feel of the template.

Also you can displace pieces with out moddifing the original design or use bufferechange. this i find very poserfull.

Check this out first you select the object of the step and right click, and select the part you are interested in displase


After the piece is selected you make right click and again you have a new menu. There you can displase the object. move it if its miss plased. or change it for an other.



As you can see now its did displace the object also added the arrow



you can also add annotation like text, arrows, images etc.

Other important think you can do its that you can rearrange steps, swap steps. make callout, add rotation icons etc. 

[img]blob:https://imgur.com/034527b1-39f4-4d72-955e-38918bb3c4f8[/img]


also if you are using sub models it automatically adds the sub model into the building instruction.




You can export  the file in PDF (you can set the DPI) or PNG (you can set the dpi) files.


thoughts. i like it very much. its near to be ready compared the licrator version that was outdated. i would like to play it arround with it little longer. Its much more flexible than lpub. but i would like to work with it and see how it runs with big models.


a little buy i have realized its that the colors of the bricks are not correct. you can change this form the interface too.