3PDF’s , 2D & 3D comments, static & dynamic stamps
If you are looking to use a tool over the period of years to manage a building asset, then somewhere you need to acknowledge changes that will occur over time, and be able to record those changes.
There will be the AMIS (Asset Management Information System) that will be managing the Data side, keeping everything up to date, as it’s the main source of truth and is kept current. But what about the graphical side?
Using 3D PDF’s allow a greater number of people access to the graphical information. This though is a snapshot in time, produced from the BIM model with graphical and data information embedded in the document.
As it’s a snapshot in time, it will not automatically update when there are changes in the real asset. You do not want to spend all your time updating plans when these changes occur, especially if you have a multitude of assets that you are managing.
Rather you would do it in a batch process. Updating all the models at intervals so you have a new Frozen start point for your graphics.
So how to track those changes? In the AMIS it may show different quantities and a comment on condition update and what happened as a note, say “new rooms created for department X“, but it will not have updated plans.
So how do we convey this information and track it?
2D Comments

Inside PDF’s you can add comments in 2D format, this is adding a comment/note to the document. It usually has a date field that can be added to it. This is useful for noting inspections and possible condition changes or damage or repair work that need to be , or has been, undertaken. So someone opening the PDF later can see that information.
The Comments can be saved to the PDF, so as long as the file is given to others, they can read those comments. These modified files can be kept for future updating for the next creation of a 3D PDF of the building.
The 2D comments are useful at the document level as they can be general notes. But if you want to point to a specific element (eg a specific wall face or location, or a specific window or door) then you can use 3D Comments
3D Comments

3D comments can be put in a 3D view. They are associated with that view and are a sub-element of that view. They are not as pretty as 2D notes but are able to point at a specific element, so can be useful to identify a specific case among many similar items. These too can be saved to the file and shared.
Stamps, simple & dynamic

There are simple stamps, like images, like “Approved” or “Inspected” or “Draft” which convey a minimal amount of information. Although they can be used quite readily for logo’s and branding too.

Also there are dynamic stamps, these usually have a bit of JavaScript behind them and can auto-fill some information into the stamp, such as current date/time. You can also have ones with form fields that can be filled out too. You can develop your own bespoke stamps both simple and dynamic. Some of these are really useful for something like regular inspections of equipment and a stamped copy with the inspector and findings can be stored for future reference.
An issue I want to explore is transparency of stamps. If you have a big red stamp on a document it can obscure what is behind it. Giving the stamp some transparency will allow what is below it to have some legibility.
Stamps can also be saved in a PDF, but there are a couple of issues around this. If someone else opens up that file, they can move that stamp around, change it or even delete it. So if you are using stamps as validation documents and need a record to be kept, what can you do? There are Security controls you can put on PDF’s as well as having digital signatures and a few other complex methods, or you could flatten the document.
Flattening in PDF’s & issues with 3D PDF’s
Flattening an element in a PDF embeds that element into the document. Its like combining all the layers into one, so they are integral.
There are a couple of tools out there that will allow you to flatten one element, like a stamp into a Document, see Selective Flattener. You cannot run this in Adobe Reader but need Adobe Acrobat to be able to use it. Also, it doesn’t work on a 3D PDF file as it freezes the 3D pane into a 2D image at the same time.

Some flattener tools do not work in 3D PDF’s as the security inbuilt for the 3D area prevent the flattener tool working. Eg the one from here.
Others will flatten everything in the document. In fact, the simplest and easiest way to do this is just to print to PDF, so you make a copy of the PDF that you are viewing. Unfortunately if you do this with a 3D PDF then the 3D pane gets frozen into a 2D image, so it ceases to be a 3D PDF file but is a 2D PDF record only. This works in Acrobat Reader as well so it’s a simple and useful process for keeping records.
End comments
These are useful tools to help record changes for future adoption into updating models. They can also be used for verification documents for inspections and other validation processes.
I’d tinkered with 2d and 3D comments before but hadn’t realised there were the stamps that are pretty cool.
An issue I have with 3D PDF’s is they are not viewable in browsers, so you just get a blank page. So I use a 2D fronticespice to convey information to users for information about the document. Stamps could be used as a quick and efficient way of building these. Especially if they are Dynamic and can allow for adding title information.
I’ll also need to explore the transparency and flattening & simple logo processes too.