3D pdf instruction creation

[Technic tango]

What I want to do:

Create a 3D pdf instruction for my now, wip ponsse buffalo dual.

What I know:

This creator here is the only  known person (to me, after much research) to have made 3D pdf lego instructions and there are some things I can infer or have gathered.

1. He is using adobe acrobat, and every piece is its own mesh, individually textured. This leads me to believe they are meshes exported as colladas, which are akin to fbxes which are both just a collection of textured 3d objects. 

2. I would need to seperately export a collada for each step, and identify which pieces have been added in each step.

This is where I am lost. I feel like there must be a more efficient way to do this. His 3D pdf file is hardly over 10mb, from what I recall, which is much less than what one would expect from so many bundled meshes. There must be a better way that i do not know of. Secondly, the issue of defining what pieces have been added. In lego instructions, they have red outlines around each newly added part to help them stand out from the others. There are two ways I can see being able to do this: The first, and arguably more complex way, is to create a custom material in studio for every colour used in the model for it to have its own outline when exported for each step. The other alternative i can think of, is longer and more tedious, but probably easier to figure out. First one would put the collada in blender, isolate which meshes in the collada are new, and apply a node texture that creates coloured outlines. (I dont know how this would be done but someting this simple should definitely be possible with blender's node system). I hope I have made my situation clear, and any insights would be greatly appreciated.

Edited December 29, 2022 by Technic tango

[vascolp]

Hi,

I got bit curious about this. By reading Comments on several of marthart models on Rebrickable, for instance this one, you will notice:

• He has a site, where he explain several things and includes free instructions
• He uses a professional software SolidEdge to model its buildings
• This software produces 3D PDF Models by a simple click
• The user models the MOC in the software using sub-models and the software produces a 3D PDF file that can be viewed in Acrobat Reader step by step by each sub-model in sequence.
• The main advantage of this is that it takes much less time to produce instructions than producing proper instructions step by step.
• Some people are not comfortable with this approach because they cannot handle it properly or are not used to it.

I understand marthart´s idea of using this software.... but probably only a good idea if you have access to a similar software.

 

[aeh5040]

This is a fascinating topic, but perhaps it might do better in the "Digital Lego" EB forum?

[Technic tango]

Hmm so he models every part in cad first? Thats alot of effort! That is a very different approach than what i had thought one may take. I do have a fair bit of experience modeling in fusion 360 so i will take a look at this program.

Upon further inspection, if one were to use a 3d pdf software, there would be no benefit over the other to design every piece from scratch. Marthart ive found, through some digging, has a very profound engineering background and likely wasnt aware of lego designing programs as his first 3d instruction was made in 2012, just 1 year after ldcad wad made. I saw this, which is a toon shader in blender so im thinking someone could make one for studio itself, or just simply apply it to the parts they want in the collada in blender itself. Alot of work, but it should be functional and feasible for someone with lesser technical knowledge. 

2 hours ago, aeh5040 said:

This is a fascinating topic, but perhaps it might do better in the "Digital Lego" EB forum?

I tried finding something like that but i was searching for variants of instructions, and decided to post here since i intended on using it for technic and my only reference was a technic creator.

[m2fel]

My guess is that he imports the 3d models of the parts from another program like stu.io into solidedge. Then builds the model in solidedge. It looks like solidege can generate the 3d pdf without further work. Thus making standard instructions would be additional work and maybe even difficult if such a function is not available in solidedge like it is in stud.io