With LDD Being Discontinued I've elected to migrate to LDraw and would like some help

[Hamish Grace]

I posted first in the topic here:  'LDD Is Dead?' and for the sake of ease on my part I'll just copy-paste what I wrote:

Hi, I'm a long-time user of LDD, love it to bits.  I love the simple UI, easy to use, nice layout of the pieces in an easy-to-search interface, and a pretty building interface.
I tried using LDraw once before but found the information and choices to be quite over-whelming.  A quick google for 'LDraw' came up with a parts list and a whole bunch of different editors and it was too much, so I stayed with LDD.
Now LDD is semi-dead, I'm trying to learn LDraw again.

I'm interested in learning about LDraw and want to know what the closest editor to LDD would be.
I've tried opening MLCad and was physically ill upon seeing the interface.  I've just now downloaded MLCad and SR-3D Builder and would like to know where the resources for learning how to use these would be.

As someone who uses advanced 3D applications on a day-to-day basis (I work in the games industry and use 3DS-Max and Maya), I'm not afraid of a complicated UI, but the information available to me for learning these LDraw applications is disparate and fragmented.
LDD was so easy to learn, all the info was right there in an easy-to-find options menu, and it was so simple to just get started and make some models, but with these LDraw applications I find myself completely lost.

My main gripe besides the hideous interfaces for MLCad, LDCad, and SR-3D Builder all, is the lack of part snapping and illegal colour/placement detection.  See here:



That is both an illegal colour and an illegal placement.
This I do not like.

My needs are simple:
-easy to use
-not completely hideous
-legal part colours only
-collision detection/snapping

Any help would be appreciated, this is all quite overwhelming and I'm a bit lost.

[Roland Melkert]

My needs are simple:
-easy to use
-not completely hideous
-legal part colours only
-collision detection/snapping

Any help would be appreciated, this is all quite overwhelming and I'm a bit lost.

Welcome to LDraw,

LDraw is by its very nature more complicated then LDD as LDD was designed for kids and LDraw is/was targeted at adults. This also means LDraw (imho) has more to offer trough its many available tools and editors.

Personally I think LDCad is only slightly hideous If you want you could tweak the colors by editing the main.gui file, as the default colors try to mimic the LEGO building booklet colors.

You could limit yourself to using the physical color parts but it will increase part bin seeking unless you set up your own custom bins (In LDCad)

SR3DBuilder and LDCad have part snapping and bricksmith is working on it I believe. Non of these (far as I  know) use collision detection though.

In LDCad snapping is disabled by default and I choose not to implement collision detection on purpose, see also:

http://www.melkert.net/LDCad/faq#faq_ps2

Above is partially bias as I'm the author of LDCad.

[Hamish Grace]

Personally I think LDCad is only slightly hideous If you want you could tweak the colors by editing the main.gui file, as the default colors try to mimic the LEGO building booklet colors.

You could limit yourself to using the physical color parts but it will increase part bin seeking unless you set up your own custom bins (In LDCad)

SR3DBuilder and LDCad have part snapping and bricksmith is working on it I believe. Non of these (far as I  know) use collision detection though.

In LDCad snapping is disabled by default and I choose not to implement collision detection on purpose, see also:

http://www.melkert.net/LDCad/faq#faq_ps2

Above is partially bias as I'm the author of LDCad.

Thank you for your reply 
How would I go about 'setting up my own custom bins', and what is part bin seeking?
Surely official part colours is a fairly important part of any LEGO CAD application..
I'm wanting to use a digital LEGO system so i can design builds and purchase the parts for them from bricklink, so official part colours is important.

I found the FAQ on your site and enabled part snapping, thanks for that.  But why no collision detection?

[Roland Melkert]

How would I go about 'setting up my own custom bins', and what is part bin seeking?
Surely official part colours is a fairly important part of any LEGO CAD application..
I'm wanting to use a digital LEGO system so i can design builds and purchase the parts for them from bricklink, so official part colours is important.

I found the FAQ on your site and enabled part snapping, thanks for that.  But why no collision detection?

You can create custom bin content by editing/adding .pbg files in the %appdata%\LDCad\partbin\  folder. See the techdocs on my site and the readme.txt files in the folder for more information.

For an example of colored parts see the set bin group (jeep/truck icon in the bin, and then e.g. the 8071 set.

Colored parts in LDraw are really just hardcoded normal part references, so you won't have the part numbers LDD uses.

There are however a few parts that do have those numbers. These are the official physically colored parts. This is an optional sub branche of the official part library but is far from complete and somewhat abandended. Mayne one of the official library authors/maintainers can give you more info on this.

Those parts can be found in the sorted/static colored parts bin (white chicken icon when using the latest library). With bin seeking I ment you will spent more time trying to find a specific part as the bin is not designed with them in mind.

As for no collision detection... The LDraw library has zero connection info so I had to add that for all the parts currently snapping, this is alot of work and having to also add full collision detection information would make it even more time consuming. Also the involved math etc would make it even more complicated while I'm not 100% sure it is that essential to begin with. I might add it one day if all other features are done tough

[Hamish Grace]

You can create custom bin content by editing/adding .pbg files in the %appdata%\LDCad\partbin\  folder. See the techdocs on my site and the readme.txt files in the folder for more information.

There are however a few parts that do have those numbers. These are the official physically colored parts. This is an optional sub branche of the official part library but is far from complete and somewhat abandended. Mayne one of the official library authors/maintainers can give you more info on this.

That... sounds like a lot of work.  Does any LDraw application support 'official colours for parts only'?  It just seems like a major oversight to me and is really game-breaking.
I might as well just stick with LDD, it's got part snapping, collision detection, and official colours only.

I'm just not seeing this:

LDraw (imho) has more to offer trough its many available tools and editors.

given the lack of things I'd consider pretty major.

I'm really wanting to like LDraw, but this is pretty major.

[Niklas Buchmann]

given the lack of things I'd consider pretty major.

I'm really wanting to like LDraw, but this is pretty major.

The LDraw vs LDD discussion depends a lot on ones perspective and requirements.

Personally, I've always used the LDraw system, first with MLCad, then with SR3d Builder and now with LDCad. I've taken a look or two at LDD, but I never felt it could offer what I wanted in a digital LEGO editor. LDD is missing lots and lots of parts, it does not support custom parts or stickers, it does not allow free placement of parts, management of larger models seems tricky (I think, maybe I haven't found the right way), the graphics are really bad and I haven't even started talking about the user interface or workflow here.

Collision detection is something I specifically do not want in an editor. I want to be the one making the decision if I can place a part or not because there are techniques that should work but do not in real life, others are considered illegal by LEGO but work just fine.
An option to limit bricks to "official" colors is problematic as well. What is an official color anyway? Is it what LEGO is producing right now? Is it anything LEGO has ever made? Do you want to include test runs or color combinations that were made for LEGOLAND etc. but never released in any set?
Part snapping of course is really useful, but that's why it is included in the more up-to-date LDraw editors.

[Hamish Grace]

The LDraw vs LDD discussion depends a lot on ones perspective and requirements.

This is true.

LDD is missing lots and lots of parts, it does not support custom parts or stickers, it does not allow free placement of parts, management of larger models seems tricky (I think, maybe I haven't found the right way)

larger models sure are super hard to do, yes.  LDraw apps are a lot better at this.
LDD is missing a lot of parts, both current runs and everything discontinued, this is half the reason I'm here.

the graphics are really bad and I haven't even started talking about the user interface or workflow here.

are we talking the UI?  because lol.  Just.. so much lol.
The 'render' tool in LDD sucks for sure, but there are exporters for POV-Ray and the likes too.

Collision detection is something I specifically do not want in an editor. I want to be the one making the decision if I can place a part or not because there are techniques that should work but do not in real life, others are considered illegal by LEGO but work just fine.

This I understand.  I have on many occasions 'fought the system', as Roland puts it.  But I have also relied on it when filling gaps and checking moving pieces too.

An option to limit bricks to "official" colors is problematic as well. What is an official color anyway? Is it what LEGO is producing right now? Is it anything LEGO has ever made? Do you want to include test runs or color combinations that were made for LEGOLAND etc. but never released in any set?

the answer to any of those questions is of course also answerable with:  'Do I want to have a spreadsheet open on the side to check if a part colour actually exists all the time'.

I guess I'm just not the type for LDraw.

[Milan Vančura]

I guess I'm just not the type for LDraw.

I do not see it in so strict way. Look at this from different point of view: LDraw is not one utility, it is whole system based on top of the parts database. And all programs are developed by somebody in his/her free time. That's something completely different than a team paid by the company. Esp. if "we" start from the scratch so often, usually because people make their SW closed-source. So it's a matter of priorities, what to develop first and what next. Two or three years ago part snapping was a sci-fi, if I'm correct. Than snapping in SR3D Builder started to be very usable. Now, we have LDCad where we even may edit snapping data comfortably in GUI. (But still we have no standard for this.)

It might be a matter of time to implement collision detection and other aspects of physics, like hinges bending or automatic check of gears turning. But yes, this is not ready yet.

[Paul Griffin]

SR3DBuilder and LDCad have part snapping and bricksmith is working on it I believe. Non of these (far as I  know) use collision detection though.

In LDCad snapping is disabled by default and I choose not to implement collision detection on purpose, see also:

http://www.melkert.net/LDCad/faq#faq_ps2

Above is partially bias as I'm the author of LDCad.

I understand why snapping is preferred over collision detection.  With collision detection, you've got about 1000 triangles per part with only so much precision to their vertices.  Plus, let's not forget that it's not really collision detection - collision detection is for finding when and how two objects touched each other, not about finding when the static friction between two non-overlapping objects is greater than some particular applied force yet less than what a child could exert.

But what "degenerate" cases would you watch out for if you were to try to implement "collision detection"?

Above is partially leading as I've got an idea of how to do collision detection and am about to try my hand at it.

[Roland Melkert]

I understand why snapping is preferred over collision detection.  With collision detection, you've got about 1000 triangles per part with only so much precision to their vertices.  Plus, let's not forget that it's not really collision detection - collision detection is for finding when and how two objects touched each other, not about finding when the static friction between two non-overlapping objects is greater than some particular applied force yet less than what a child could exert.

I don't think this kind of snapping is possible using just the raw LDraw data as even with bfc you are not always sure about what is inside or outside etc.

But what "degenerate" cases would you watch out for if you were to try to implement "collision detection"?

Not all fitting connections are modeled using the exact same shapes / tube orientation etc. In LDCad I mainly simplified most things to pen / hole variants and most of the rest is done using simple (group) named orientation hotspots.