Five things you may not know about LDraw: Guest editorial by Matt Wagner

Today we feature a guest editorial by Matt Wagner on virtual building. As some of you may have noticed I share a lot of these thoughts with Matt and find the prejudice against LDraw to be quite thoughtfree.

Anyway, I’ll pass you over to Matt.

Thanks to Andrew and Tim for the chance to share some of what I know about LDraw. First off, I want to make it clear that by no means do I represent the entire LDraw community; I’m only one of many virtual LEGO builders out there.

What I’d like to share is this:

Five things you might not know about LDraw:

  1. LDraw is free. Anyone can download and use LDraw (and MLCAD and all of the associated programs), and the most often-used rendering program (called POV-Ray) used to create the 3D images is also free. Get started at
  2. LDraw’s parts library is both unlimited and limited. Anyone who’s used the program knows that the extensive part library allows you to click and drag into your virtual model to your heart’s content. But since LDraw is not officially licensed by LEGO, all those parts files are created by everyday users out of polygons and groups of polygons called primitives. And since nobody’s getting paid for their work, the creation of parts is slow and up to the community. takes these parts and releases official parts updates periodically after ensuring that each part meets their quality requirements; however, no official parts updates have been released in over 5 years. Parts that are created in the meantime get placed in the “unofficial” parts library on the LDraw website, but have varying degrees of quality and mistakes until they are approved as official, and some parts that you might hope to find simply haven’t been created in LDraw yet. For example, the minifig heads with facial expressions other than the benign-looking smile, as well as all of the new male and female hairpieces, all pieces that have been available for years now in real life LEGO pieces, are still unavailable in LDraw.
  3. LDraw has its own unique challenges. It is true that gravity and tension are not something you need to worry about in LDraw: as the program is basically placing bricks in a 3D space, it is possible to place a 2×4 brick going right through another 2×4 brick, something virtual builders call “impossible building.” This may be why some people consider LDraw to be less of a challenge than building with actual LEGO pieces. But building pieces at an angle, something that may require only the positioning of a hinge piece or the click of a bracket in real life, is much more difficult in LDraw. Anything built using SNOT is harder than in real life. Large models become very cumbersome in LDraw. Doing these things is possible, but they require complicated extra steps involving multi-part files and careful aligning of connections and angles.
  4. Publishing LDraw models can also be a challenge, something that can become more complicated than photographing with a lightbox. LDView is a great program that creates a clean-looking image of your virtual moc in seconds. But for those who want to approach the realism seen in some of the virtual modelers who’ve been featured on Brothers-Brick before, you need to learn how to use POV-Ray: a free ray-tracing program. POV-Ray allows you to place light sources, floors, skies, backgrounds, and other tools to enhance your model’s presentation. POV-Ray also has a feature called radiosity which is something that adds a lot of light and realism to a render, but also stretches out render times to several hours or even days. There are a few tutorials out there on how to use some of these advanced features with POV-Ray; Brichkhelf user Koyan’s tutorial is one that I have used.
  5. Virtual LEGO and real-life LEGO can complement each other. Say you’re wanting to build a new model, but you don’t have all of the pieces you need. You want to make sure you can fit everything together the way you’re imagining. You can build it in LDraw first to best visualize your model. Then you know exactly which parts you need to order on Bricklink. Or here’s another scenario: you’ve just built an amazing model out of pieces that you have, but another contest comes along that requires the use of pieces that are tied up in that last creation. You hate to have buy new pieces this time, so what do you do? Build it in LDraw and save a virtual version of your model, so that you can archive it forever and free up those precious bricks. Thanks.

I hope I’ve helped broaden your views on LDraw and virtual LEGO in general, and hopefully I’ve dispelled some of the misconceptions that cause virtual entries to be prohibited from competing in LEGO contests.

13 comments on “Five things you may not know about LDraw: Guest editorial by Matt Wagner

  1. anoved

    Another great thing you can do with LDraw is use LPub to create building instructions for your models. For example, in the past I’ve posted instructions for some of my alternate models.

    At any rate, I primarily use LDraw for the last point mentioned by Matt – to virtually “record” models I’ve built in real life, freeing up the bricks for other creations. This is especially useful if you’ve got a small collection! I’ve also found that the process of methodically rebuilding a model as I enter it in LDraw often helps me find ways to improve the construction.

    Last but not least, Mac users will want to check out Bricksmith for building LDraw models. Have fun!

  2. legovaughan

    “…and find the prejudice against LDraw to be quite thoughtfree. ”

    hehehe ‘thoughtfree’ – that made me chuckle.

  3. tedwwward

    All very nice but you have not addressed the primary concern that causes LDraw entries to be prohibited: the perceived unfairness of unlimited number of elements and excessive numbers of “rare” elements.

    There is also the question of whether or not this is LEGO building. If I painted a realistic picture of a LEGO creation that showed only accurate, possible building techniques should that be allowed? What about a pencil sketch?

    LDraw is a great tool, as your final point makes clear, but there is no basis for allowing such in contests. Are we to start allowing LDraw renderings at Fests and Cons? Maybe I should take good photos of my MOCs and put them on the table at our clubs next public display. That would be sure to impress people and encourage them to build or join our club.

    Promote the tool but I think you are barking up the wrong tree asking for more.

  4. Gambort Post author

    Ted> Classic Castle have been dealing with this for years by simply forboidding excessive use of “rare” elements in CAD. Furthermore are you suggesting that wallet size should be an acceptable substitute for talent?

    I guess you have a different take on the hobby to me. I like it for seeing great *creations* in the LEGO medium. If someone draws them well enough (eg. Mike Rayhawk) I like them too. The actual ABS is of secondary importance to me, the talent displayed in the creation (and presentation) is more important.

  5. seanmichaelragan

    I would add to the rare elements issue the point that there is very little to no rational mapping between L-DRAW colors and real LEGO colors. L-DRAW will let you use any part in any color, when in fact the parts you require may not ever have been made in anything like the color you used in the virtual model. In my mind, this is the biggest obstacle to using L-DRAW all the time as a prototyping too.

  6. Eric Burdo

    LPub is a great tool. When we did the LEGO MINDSTORMS One Kit Wonders book, we used LDraw to do all the building instructions. There are programs you can get to compare your instructions to the actual parts list of the MINDSTORMS kit. It tells you if you can build the model from the Retail kit (or the Education kit).

    I think more tools like that would make the LPub stuff even better.

  7. tedwwward

    Gambort> I am not trying to denigrate those who like to “build” with LDraw but it is a subset, spin-off whatever you like of the hobby. It is a tool that perhaps more people would use if they knew more about it but it is not a finished product in terms of our hobby. You would not enter renderings of a proposed building in an architectural contest for actual buildings. Entering LDraw renderings, to most of us, is the same thing.

    I understand that some contests allow LDraw and I would be happy to see more that offer LDraw their own category but you have not answered my question: if I accurately draw a MOC should I be able to enter that in contests and displays on an equal footing with in real-life (IRL) MOCs? For most people the answer is no and nothing so far presented is going to change that view.

    As for the red-herring of “wallet-size”, this is also dealt with by most contests by having a parts limit or baseplate-size limit or multiple categories and combinations of all three approaches. I don’t generally share that objection to LDraw due to these limits in most contests that apply to both virtual and IRL MOCs. I was simply pointing out a major omission in the thesis.

    Comparing MOCs to pictures of MOCs is like comparing apples to pictures of apples. Just not the same thing. Equally valid with both different and similar difficulties and skills but in the end, not the same.

  8. Andrew

    Ted, where I feel your argument breaks down is in the fact that we’re mainly talking about restrictions placed on online contests. For example, contest judges don’t go to each builder’s home to view their entries in person. To use your metaphor, the “currency” within the online LEGO fan community is indeed pictures of apples, not real apples.

    Like Tim (Gambort), my interest is in a LEGO creation’s design and presentation, not whether or not it’s been built from physical bricks (as demonstrated by our fairly extensive CAD category of virtual creations here on TBB).

    If I were to go to a convention and see a printout of an LDraw design, I might see that differently (conventions are about seeing the LEGO creation in person), but in the online world, I don’t really distinguish between a well-photographed physical model and a well-rendered virtual model. In fact, as more builders take the time to post-process their photos and as rendering becomes more and more photo-realistic, at some point the line is going to blur. As someone interested in LEGO as an expression of creativity (and possiblity), I’m fine with that.

  9. Gambort Post author

    ‘To use your metaphor, the “currency” within the online LEGO fan community is indeed pictures of apples, not real apples.’ was Andrew saying exactly what I was going to.

    ‘If someone draws them well enough (eg. Mike Rayhawk) I like them too.’ was me trying to imply that I would accept a drawing if it was done well enough. It would have to be an accurate representation of a LEGO model though.

    Furthermore the “red herring” you claim is a “red herring” of your own devising. You can’t complain about LDraw users using expensive parts and accept them from people who are rich enough to afford them.

    And I believe some people have taken laptops showcasing (in full 3D) various LDraw models to conferences and they have been broadly well received.

  10. matt

    I appreciate a lively discussion, and I’m glad that opinions are going back and forth with respect for each side.

    But Ted! Point #2 in my editorial began to address the issue of unlimited parts, but maybe I should add a few things to clarify why that is not a valid basis for an argument against LDraw. Forgive me if I echo what Tim and Andrew might have already said.

    Like I said in the editorial, LDraw library is not unlimited in the sense that I explained. But even it was, unlimited parts do not automatically make a great builder or automatically create great and amazing mocs (obviously this is not true in LDraw, just take a look at my mocs!). This should be fairly obvious, but I think it needs to be explored a little. Often, the best builders have huge part libraries but this is only because they’ve invested time and money into the hobby; if one were to argue that they first acquired their massive parts libraries and then became great builders, that would be just ridiculous. It’s a correlation that some of the best builders have the biggest part libraries, but not cause-and-effect. Also as a side note, I’m not understanding your point on how multiple categories in a contest keep those builders with the most extensive parts libraries from competing.

    The spirit of LEGO contests, in my opinion, is based on rewarding people with good ideas. Innovation is what wins contests, not unlimited parts. Look at the winners of the most recent online LEGO contests and I would bet that most of the winners used some type of interesting part usage, or had a great sense of humor, or did something that was never done before, in order to win. LDraw entries should be allowed into this arena because good ideas are not unique to plastic bricks or lines of code.

  11. Tedward

    I must say, I wish that the last sentence of the original article had specified, “prohibited from competing in online LEGO contests”.

    Now that I am addressing the right topic, I think I have to change my mind. Andrew and Tim made good points about the online contest being a contest of pictures. I assume however they will acknowledge that ANY method used to create those pictures would have to be accepted as valid including paintings, drawings, “photoshopped” images, etc so long as it was accurately depicting a build possible with LEGO elements. Of course that brings up how to “prove” a design is possible without actually building it IRL but that’s not my problem. :)

    What really changed my mind is what Matt said about the nature of online contests, “The spirit of LEGO contests, in my opinion, is based on rewarding people with good ideas.” I have to say that when I think about it I have to agree. As he mentions, humour, innovation and technical skill are what makes winning entries to me. So long as the entry could be made using actual bricks there really is no difference between a picture made by taking a photograph of a MOC or by working it up in LDraw.

    Thanks for the discussion.

  12. matt

    I’m glad we agree, though I’d be hesitant to group LDraw in with just any drawing or painting of LEGO. LDraw has a certain standard that does allow bricks that are added in studs-on-top format to fit together. But I must admit that paintings or drawings, if they were able to portray a feasible model, cannot be excluded based on that argument.

    And you bring up a good point about LDraw entries, and that is that those of us who build them do need some type of accountability to ensure that the build is actually possible (from both a spatial perspective as well as color usage) if it is to compete against real-life-bricks built entries. I have seen only one contest in which this was a stipulation, and it’s because Tim was involved in it.

  13. Gambort Post author

    Ted> I agree totally about pictures so long as they truly represent a buildable model. Glad we agree.

    matt> It requires someone with a bit of experience to judge the buildability of a CAD model but that can also be true of brick builds where people mod elements (which is often dissallowed). I suspect most contest judges have a good idea of what is readily available and can spot blatant cheating pretty easily.

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