Mecabricks Interview (Blog or Die! Entry #16)

Accepted entry for the “Interview” category.

Author: Caleb Inman (VAkkron)

Word Count: 1,674

Mecabricks Interview

Screenshot-2018-1-14 Mecabricks com.png

It is my pleasure to present an interview with the mysterious man known online as Scrubs, creator and supporter of Lego CAD and rendering software Mecabricks.  Ladies, gentlemen, and constant readers, please put your hands together and lend your ears as we pull back the curtain on the life and work of the one and only Mr. Nicolas Jarraud!

[Caleb Inman: CI; Nicolas Jarraud: NJ]

CI: Hello Nicolas!  Can you give me a brief description of yourself, either education or career, and your interest in Lego?

NJ: I was born in France in the early 80s and like most kids there I played with LEGO in my childhood. The sets that we owned with my sister are now in a big case stored at my parents’ place. I currently live on the other side of the globe in New Zealand where I moved more than a decade ago. Until recently I was designing production equipment for a medical company. I am now working for a big tech company as an optical engineer where we design the next generation cockpits for traditional and self-driving cars.

My dark age finished somewhere in 2011 when I started Mecabricks. I had to catch up on 15 years of LEGO products and history! From this date, I accumulated a big amount of sets. Way too many according to my wife. Some of them to keep like the modular buildings and others only for parts that I model.


Render credit: Nicolas

CI: Impressive to hear you actually buy parts in order to model them for your parts library.  That’s an amazing level of dedication.  Do you actually use those Lego pieces that you’ve bought to build anything?  What made you decide to devote your time to virtual building, and why do you believe virtual building is important?  What are benefits of digital Lego modelling over physical building?

NJ: I am not really a builder. I can barely follow the instructions from the LEGO manuals and I always have pieces remaining at the end! I am not bringing any news by saying that LEGO is expensive. Building virtually allows to use any quantities of any parts in any colours. Freedom! You are not constrained by physics. Parts can intersect and are not subject to gravity. This is a different way of thinking and it can appeal to both people wishing to build their creations later with real bricks or simply create something more abstract that is not possible in real life.

To put it in a wider context, this is also a fun way for kids (or adults) to discover CAD (Computer-Aided Design) and maybe generate vocations. With the likes of 3D printing or laser cutting being more and more accessible to the public, understanding CAD system is a nice to have skill.

CI: I know exactly what you mean, and in fact I was one of those kids who decided to be an engineer because of my experiences with Lego CAD programs.  However, I used LDD, and there were other CAD programs available for Lego building before Mecabricks.  Can you describe your experience with them, and the problems they had that you are trying to solve with Mecabricks?

NJ: LDD is not for me. Too many constraints. I am not able to build anything with it. I always end up fighting with parts to put them in the right orientation at the right place. LDraw based CAD software were maybe the opposite at the time. Too much freedom and therefore the same issues. I have also been asked multiple times why Mecabricks was not using the LDraw part library – For the same reason I wanted something unique for the building tool, I did not want to depend on a third-party library. I managed to create a whole separate system using modern tools and modern formats.

Overall, I love technical challenges which was probably the main driver. Bringing more options to people is also not a bad thing. All of them are very different in the way they work.


Render and model by saabfan2013

CI: So Mecabricks is essentially build from the ground up.  Very impressive.  What else makes Mecabricks unique?  Has developing a community forum and website helped to generate interest in your CAD program?

NJ: Mecabricks doesn’t need to be installed. This is only online. You open your browser on your computer or your tablet and you have all your files available with the latest version of the tools and the parts. It all happens seamlessly. This is a big advantage for example for schools where it can be a complicated process to get anything installed on the kids’ machines.

Mecabricks is also a great place to discuss everything about digital LEGO. The forum is still pretty basic but includes a lot of great tips for building and rendering. You will find there talented people with different skills: Renderbricks for technical stuff, Zanna for the artistic side, Saabfan (one of the designer of the Apollo Saturn V set)  for the building technics to name a few.

CI: You are doing some ground-breaking work with digital render systems.  First, tell me how these renders are becoming more and more realistic, and closer to mimicking real-life photography.

NJ: It is only in 2014 that I have been pushed by user Renderbricks to create export tools so that models could be opened in traditional 3D software. This has brought Mecabricks to a new level and I am now working at making this even easier and more accessible to a wider audience.

My favourite software is of course Blender and in the recent years the community has been really active. The rendering engine called Cycles is now mature and powerful. I am closely following the development and every new feature they provide is implemented in the Add-ons available on Mecabricks.

In the past few years I also spent way too much time observing and taking close shots of LEGO elements to understand how they interact with light. Being an optical engineer was a big help.


Render credit: Nicolas

CI: I wouldn’t have thought of that.  That’s a great way to combine career experience with your hobby.  I am sure the technical expertise extends far beyond light and computer programming. Is the hardware system just as complex?  Also, what will be the availability of this render feature?

NJ: This new feature of Mecabricks will be available in the second half of January 2018. It will be possible to create stunning images in your browser without special knowledge. Although the use is very simple, this is not the case of the system that is running in the background.


Render by Renderbricks

CI: I have heard the phrase “render farm” used.  Can you describe what that means and how is this the best option for builders who want to render their models?

NJ: The main issue with 3D rendering is that it takes a lot of power and a lot of time. It can take multiple hours for common home computers to calculate a single frame. So, the idea here is to send the LEGO scene to special computers that are built for this task only. When the render button is clicked, a 3D file is created and sent to New Zealand. This file is then converted to a Blender scene and shared among multiple computers to be rendered. The final image is assembled and composited before being sent back to the user.

As an example, a 4K images (3840×2160) that would take more than 3 hours to be generated on my 3-year-old iMac is only taking about 7 minutes with the system I designed and built. Everything is optimized for LEGO rendering.

Ease of use, quick turnaround and guarantee to use the latest render features available are the key aspects of the Mecabricks render farm.


Render by Nicolas; Model by IstakaCiti (link unavailable)

CI: Who is your target audience?  Can builders from other Lego CAD software export their models into Mecabricks?

NJ: Anybody willing to showcase a digital 3D LEGO creation. I think it will be popular among designers posting projects on the LEGO Ideas platform. Having nice presentation images is a bonus to ensure a good visibility.

It is currently possible to import LDD models in Mecabricks with some limitations. But with minimal rework in the workshop the result it pretty good. Obviously, I am not a wizard and parts not available yet in Mecabricks cannot be imported.

CI: What will be the cost to use the rendering feature?

NJ: To be announced very soon but very affordable anyway. The goal is to find a balance to be able to pay for electrical power and any future hardware development.


Render by Renderbricks

CI: What do you plan to do next?  Where will your innovations take you in the future?

NJ: The to-do list is never ending and the community growing. So, I try to share my time between running what is currently existing and designing the future of Mecabricks.

The next big feature that is long overdue is an instruction builder. The goal is to make a tool that is both easy to use and powerful enough to create high quality manuals.

CI: I know many builders from both the physical and virtual branches of the hobby have been waiting for an easy, comprehensive instruction builder for a long time.  That will be a massive innovation.  Before I conclude this interview, is there anything else you’d like to share with these wonderful constant readers?

NJ: Building digital LEGO models is fun and the possibilities endless. Give it a try.


Render and model by saabfan2013

CI: You do incredible work and I have seen the excitement of people who have been able to use the render farm.  The results look spectacular.  Thank you for doing this interview, and I hope you keep up your excellent work!  Best of luck in the future.


*All images in this interview are made with the Mecabricks render engine and courtesy of their respective creators.

32 thoughts on “Mecabricks Interview (Blog or Die! Entry #16)

  1. Awesome interview. Learned a ton. Looking at these “renders”, I realize more and more that they are getting harder and harder to distinguish from photography of actual brick. Really nailed the lighting in all of the examples. If the end-goal for a builder is the model image (as opposed to part/color availability, etc.) Mecabricks and the render feature look like really great options.


    1. Yeah, this stuff is super cool. I still haven’t gotten my hands on the software much, but I see that a few veterans have commented below. I’m glad I could reach new audiences with this interview, that was the goal! Thanks Ted.


  2. Great interview. I’ll have to look into Mecabricks. I didn’t know about it. I tried LDD a long time ago and found it too cumbersome so have shied away from digital altogether, but I like the idea of being able to try out a design before buying a bunch of parts. The render feature is pretty brilliant. A lot of the digital builds I see posted are pretty hard on the eyes, maybe they’ll get better by using this. You left out one question I’m always wondering, how impossible would adding physics to digital building be? I’m guessing it’d be really hard to have the program computer stress analysis. Would be helpful to people who actually planned to build the design with real bricks.


    1. Jake. Excellent question. I read this last night and I have been thinking about it for a while. The cool part is that Nicolas is already using Blender, a 3D polygonal CAD program (you might be familiar with it). I know that Blender has capacity to do some of these simulations.

      The way that the Lego models are imported to Blender right now allow each piece to become a discrete element. (At least I think that’s how it works.) That way you can add things like light, noise, surface patterns, or other effects that are build into basic CAD programs like Blender. So if each piece is already a discrete body recognized in Blender, they should be subject to Blender’s simulation programs, like you said, such as FEA, gravity, etc. Now, the difficult part would be attributing weight, composition, and other fundamental physical and chemical characteristics to each piece, but overall I imagine it would be doable. Perhaps this is something I can look into in the future. Maybe I could even build my Senior Project around it. 😛

      Thanks for raising a really good question. That would be a great service for builders, but also for people who use Lego as a mock-up for other engineering applications.


      1. It seems like it would be difficult to me. Need to calculate clutch power on each connection that is being pulled apart, the weight bearing on each piece to see if it would be crushed, and then you have to figure out if it can survive a swoosh. That is the most important part. And if it doesn’t then the model has to fall on the floor and the programmer has to figure out how to put it all back together. 🙂


      2. Ack, yeah, you’re right. There would be a lot that goes into it. Who knows though, my gut tells me it is possible. I know clutch power differs from connection to connection, even color to color, but if that could be averaged, then a model could possibly be simulated as a solid body with a known weak point or stress concentration along each piece seam. That way, “failure” would still be connected to the actual destruction of a MOC. It would require a dang lot of simulated stress concentrations, though.

        I’m probably blathering. I’ve got very little experience in this. But alas, it’s cool to dream about.


  3. Looking at these renders a little more closely. That blue spaceship and what looks like a window in the reflection of the bubble windscreen, was that added in the render or photoshopped in later? Maybe I should just go to the source and ask the question, but thought that was pretty impressive if Mecabricks could go that far with their lighting options.


    1. Hello,

      this is Michael from Renderbricks. There’s nothing done by Photoshop in this case. The Advanced Addon is using textures for scratches, grease and fingerprints. You can render the pictures as a so called Foreground Plate and add your own background to it. For the blue spaceship Scrubs used a real environment as a HDR map (High Dynamic Range) what you can see in the background. The table and reflections is rendered.


      1. That is cool. I’m impressed. It looks like a photo to me. You guys have done an excellent job of making it realistic. It is also kind of ironic. I think when most of us take pictures of our models we are trying hard to get rid of smudges, fingerprints, window reflections, etc. And you guys have worked out ways to add them in. Maybe you should work in a feature where one or two brick are pushed down all the way or slightly out of square. That would add to the realism. Thanks for responding.


      2. This is actually possible in the add-on I made for Blender and the Mecabricks render farm. There is a value that can be changed to randomly slightly rotate/move the parts to give the impress that they have been assembled by hand. I know how ironic it is. Photographers try so hard to make clean and tidy photos when we try so hard to replicated the errors a photographer can do 😉


      3. I love the comment Scrubs makes here, and Jake pointed it out too. The real world is, by nature, messy and subject to entropy, so order is difficult to achieve. Virtual environments are, by default, perfect, rectangular, and tidy, so mimicking the advanced disorder of the real world is the best way to make something look realistic. Video games drop huge dollars into deteriorated and well-used aesthetic for their environments, and obviously renders deserve the same treatment. It is a fascinating concept.


      4. Thanks for joining the conversation, Michael. I really appreciate it. You are a mighty source of knowledge on the subject, and as Scrubs credited you, partially responsible for the current software we have. Thank you to Scrubs as well for stopping by. That means a lot to me.


  4. Fantastic article VA! As someone who has worked with CAD and rendering programs before, I’m honestly blown away by the level of detail on display here! Scrubs has done some incredible work on building this site, and all of that effort clearly shows. I look forward to where all of this technology takes us in the future. Great stuff!


  5. This is a good example for a very useful and fun to use digital transformation of a great product: LEGO. I hope Nicolas will get all the attention he, the core people giving support and the community deserves. Maybe some honor by The LEGO Group some day because Mecabricks is gold.

    I am using this as auniversity professor for my lectures and for my trainees at my studio as a simple, painless and very satisfying step into the complex world of 3d computergraphics with great and professional results out-of-the-box. I will also teach kids at school with a neat concept using Mecabricks and Blender.

    To me it’s a real unique innovative tool and workflow. Honestly: this should be a must have for TLG. It has so much influencing potential and is a bridge beetween the real and virtual branding of LEGO.

    Especially for all LEGO fans who have not the skills to do 3d … yet. I will keep on researching and testing to help Nicolas to make Mecabricks better and better.

    Cheers to all. LEGO is more.


    1. Hey, that’s an idea… Lego definitely struggles getting on board the digital side of things. This is professional-level software that they could certainly benefit from using.

      You’re using this in a classroom? That is awesome! Frankly, I’m jealous. I wish I could attend your school. That sounds like a brilliant combination of education and hands-on learning, all in an environment that’s very interesting. Congrats for getting that to work.


  6. I was in college when computer rendering was really getting going, Pixar was about six years away from giving us Toy Story. There were shorts here and there and scenes in big budget flicks, but seeing what animators had to endure just to get a single image rendered instantly turned me off to digital. I’m way too impatient to wait 17 hours for a low res image to be rendered. I’ve tried LDD and found it frustrating. I have a digital pad I now have to use for a personal business for simply drawing and it is completely backwards to how my brain works and how my skills have been trained. I have great difficulty understanding HTML and anything computer language oriented. And I find that having to “dumb down” in order to do anything almost insulting to a basic work ethic. In short, I hate computers.


    This interview has piqued my interest. If for anything because I know that there is tremendous potential in this branch of art and I know that I have much schooling to do in order to just keep up. I’m still waiting for physics to play a MAJOR roll in this medium, but I think it’s more of an affectation of equality. My model fell apart because I didn’t account for gravity but rendered builds don’t. I know that is truly an indispensable tool in reality. But reality isn’t necessary on a computer, and that’s the hardest thing to wrap my brain around. But that is an exciting way to view sculpture that my practical mind can now shut the fuck up about.


    1. I’m glad that this interview could spark your interest for digital building. Personally I found considering stability and how the model would behave irl one of the most interesting parts about digital building. I make sure that all of the models I do are buildable irl. All of my builds shown above have been tested with real bricks. (just not in the right colours) 😉


    2. As Saabfan mentions below, representing proper physics sometimes plays a significant and entertaining role for digital creators. For others, the lack of physics is the main benefit.

      For me, it’s always been more of a handicap. I know that because of physics, my Cloud City model would never, ever have a chance of existing in reality. When I was designing my parents’ wedding portrait, I finished all the regular design then spent about 15 hours throwing as much Technic pieces and support onto the backside as I could Then I crossed my fingers, hoped, prayed, and built the thing in real life. It was a miracle that it stayed together at all, because I was literally shooting in the dark to see if it would work or not.

      I mentioned to Jake just now (up a little ways) that a gravity simulator might actually be possible. Nicolas has built the Mecabricks render engine in Blender, but Blender is useful for far more than rendering. One of its uses is indeed simulation, so I am interested to play around with those features and see what sort of realism I can concoct.

      Thanks for chiming in, Matt. I’ve always had the feeling that you are turned off to the heavily digital. I would be curious to see your take on it as an art form, however, especially with the unlimited possibility of a program like Blender.


  7. Official Contest Review
    Entry # 16
    Title: Mecabricks Interview
    Author: Caleb Inman (VAkkron)
    Views: 193 Comments: 16

    Favorite Question/answer combo: Q: “I have heard the phrase “render farm” used. Can you describe what that means and how is this the best option for builders who want to render their models?” For the answer, consult the interview.

    Favorite Comment inspired by the entry: “You guys have done an excellent job of making it realistic. It is also kind of ironic. I think when most of us take pictures of our models we are trying hard to get rid of smudges, fingerprints, window reflections, etc. And you guys have worked out ways to add them in.” – Jake RF

    Single Sentence Summary: An interview with Nicolas Jarraud, the creator of Mecabricks LegoCAD and rendering software.

    The Good:

    1. You selected an unexpected and fascinating subject to interview, Judging by the comments I think it’s safe to say that most of the readers were not familiar with the product/service and very receptive to the information. I can also count myself among those who have been very frustrated with traditional digital building programs and for the first time in a long time it seems like something I’d like to try. Picking a good interviewee is half the battle so you get points for a good choice.

    2. A skeptic might say this was an advertisement masquerading as an interview but you did a good job of tempering this issue by your introductory background questions that helped to make the subject more relatable and seem like one of us, as opposed to a faceless salesman (one of them). It also helped that you educated the reader beyond just the sales pitch, for example I had no idea what a render farm was before reading this post. I might have been able to reason my way through it, but it was nice to have a concise, accurate explanation of the term. There were a few of those moments that added value to the interview. The article was accessible to the novice (me) and never turned into a force-fed shameless sales pitch. Kudos for handling the topic and your subject with both respect and a degree of subtlety.

    3. Good questions make all the difference, no matter how interesting an interviewee may be, without the right questions it’s easy to lose focus and fail to make the most of the interaction. While you may not re-invent the interview, the questions proceeded in a solid logical, chronological order and I was hard pressed to think of a follow up question when I was done reading. The renders displayed in the piece were well selected and there were just the right amount of examples. Given the topic, I think you made the most of the questions.

    The Bad:

    1. I think it might have been helpful to have a screenshot or two of the actual program in action, showing the interface in action. I’m not sure if that’s possible or if you asked and were rejected but that was once curious itch I had that needed to be scratched. While I was certainly able to find that information by following the link and experimenting with Mecabricks myself, I know some people are too lazy or apathetic to follow the link and it might have helped to better illustrate the topic for that slice of the audience. It was nice that a commenter included a screenshot, because the interview felt a little incomplete without it.

    2. You had a tendency to stuff too many questions into a single block and I think it might have overwhelmed your subject a little bit because on a couple of occasions the answer(s) seemed somewhat incomplete. Considering English is probably his second language Nicolas did remarkably well, but I think you could have helped him out a bit by spacing out the questions to get everything covered.

    3. This falls into the category of suggestions for improvement rather than a flaw that needs to be addressed but it might have been fun to include your own experience designing a model with the product and it might have created another series of questions. While the focus should always be on the interviewee, your style is more conversational and it might have been interesting to read about him helping you through a problem or commenting on your experience. Just a thought for next time, because I do hope this isn’t the last interview you conduct for the blog, you’ve got a skill for it.

    The Whatever:
    The article mad me curious as to how you landed on that subject. Were you using the product and thought “hey this would make a great interview” or was it recommended to you? I don’t think you needed to include it in the interview but the result was entertaining enough that the thought crossed my mind.


    1. Thanks for asking the “Whatever” question, because it tells a lot of the backstory for this interview. As it turns out, I have never used the render farm, but I have seen so many hundreds of examples from the digital creators I follow (Saabfan and Renderbricks among them) that I had to get behind the scenes. I have also been following the software since 2014, and the render engine has progressed from a Blender add-on to a totally in-browser supported user interface. I happened to teach myself Blender last summer to gain experience in polygonal CAD, and talking to Saabfan and other guys made me really curious how Mecabricks utilized the software. In the last year, it has morphed into something totally different, and I haven’t done a good job at keeping up. This interview was as much for me as for you, and I am glad to feel caught up on the details.

      I can see the skeptic’s interpretation of this as a sales pitch, and I tried very carefully to avoid that. I was the one who went after Scrubs initially, and he was gracious enough to break from work long enough to respond. My intent with the interview is to show primarily physical builders a good example of why digital building is important, and that it can honestly hold its own. My question of money was more of a warning to that same audience that this isn’t free, rather than trying to sell anything. Still, if it causes anyone to go support the incredible work that Scrubs is doing, I would be proud. He is such a hard-working and community-focused person that he would no doubt listen to some new voices asking for other features. Maybe you and other readers of this interview will be those voices.

      Your 2nd Bad point is fully on me. I sent Nicolas a set of questions, and when I got his replies I modified my questions to sound more conversational. I probably broke every rule of proper interviewing by doing that, but I think (hope, cross my fingers) that the result was worthwhile.

      Again, thanks for your comment, Keith. Both your comment here and on my Izzy article have made me consider writing again on those topics to address some of the stuff that you brought up.


  8. Wow, fantastic weblog layout! How long have you ever been running a blog for? you made running a blog glance easy. The whole glance of your site is magnificent, as well as the content material!


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