LibreOffice Conference 2026: Slide sections in Impress

Duration: 7:56 1106 transcript words EN summary

Video summary

The video introduces a new feature in LibreOffice Impress called "slide sections," presented by Pranam Lashkari from Collabora, which aims to bring order to long and complex presentations. Without this feature, slides often appear disorganized and difficult to navigate, but slide sections allow users to group related slides into named categories that significantly improve clarity and structure. The presenter demonstrates how these sections can be used to organize content by topic, assign specific parts of a deck to different presenters in collaborative environments, or simply collapse irrelevant groups to focus on the current section being edited. This organizational capability makes managing large presentations much easier by allowing users to move entire blocks of slides at once rather than dragging individual slides one by one. Under the hood, the feature relies on a streamlined data structure that stores only the section name, a unique GUID identifier, and a starting index, rather than listing every slide within each section. The system automatically determines the range of slides for a section based on where it starts and where the next section begins, extending to the end of the deck if no subsequent section is defined. This design simplifies the underlying code and makes undo operations more efficient by storing the complete state of sections rather than just changes. Furthermore, the implementation ensures that any modifications to sections are instantly reflected in collaborative online views, maintaining real-time synchronization for teams working together on the same document. The technical discussion also addresses interoperability with Microsoft PowerPoint, noting that while PowerPoint uses a fixed string identifier for sections, LibreOffice utilizes a flexible GUID system that maps bidirectionally between slides and section data. Although the raw XML representation of these sections might look intimidating to users unfamiliar with ODF file formats, it remains readable and manageable within the software's architecture. The user interface allows for easy management through right-click menus where users can add, rename, remove, or collapse sections, while also supporting a new maximized view in Collabora Online and Kood that displays more slides simultaneously. This enhanced viewing mode further leverages sectioning to help users visualize the overall flow of their presentation without getting lost in excessive detail. In conclusion, the slide sections feature represents a significant improvement for anyone creating lengthy or multi-author presentations by providing robust tools for organization and collaboration. The presenter emphasizes that despite the complex-looking XML behind the scenes, the functionality is straightforward and stable, encouraging users to adopt this feature to streamline their workflow. By enabling precise control over large groups of slides and supporting seamless teamwork, LibreOffice Impress now offers capabilities that rival proprietary software while maintaining its open-source flexibility. The presentation ends with an invitation for users to try out these new features immediately, highlighting how they make the task of building professional presentations less tedious and more efficient.

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start. >> So I'm Pranam Lashkari as you can read from there. I'm a software engineer and uh work for Collabora and my today's topic is slid section in impress. Another very boring presentation is going to be but I'll try to keep you awake. First of all, why you need slide sections? Because your presentations without it looks like this. It's all mess everywhere. Not the kids. They are not the mess. And with section, it looks amazing and clean and organized like this thing. So for again very boring text, why do you need it? You can name your sections as as as let me just give you a demo why I'm showing you this thing. If you can see here I have sections here organized. First section is hi with my name there and then there is all this slide group there. Why? So now I exactly know what I'm going to talk about how I organized. I can go into flow there. So what are the slide section? You can group sections and then you can name it and everything there. So how does it work? That's the main focus I'm going to keep here. And why do we need that? Just in case if you have very long decks, you can group them and then collapse and focus on only slides which you are working on right now on this one particular group. Then there are some presentations which are done by multiple people because multiple people are presenting. So you can make sections for each person. So one person works on just one section and doesn't mess up uh someone else's slide. And um this also helps because with sections you can select entire section and move entire section to a different completely different position. So it makes your life a little bit easier when moving a dozen of slide at a time. Under the hood, what do we have there? So if we focus on the coding part, we have one slide section manager per document. And there is this one structure which just stores very simple information. the name of the section and the section identified by GU ID and we also store index there. So how we we don't store what slides are in the slide section. We just store the starting index and that section continues until the next section is specified. So if uh one section starts at slide two, if there is no section specified after that uh then it goes up to the end of the uh slide deck. If there is another section specified at slide 10, then that section ends at slide 10. And you can perform simple uh group actions add, remove, rename, move. And uh we we done this uh using Uno API uh for the online. And uh for for the undo part we store the entire uh entire uh section data not just uh what you have changed in the section but entire list of section with a start index name. Uh so it makes uh our life as a developer a little bit easier than maintaining just the delta. And if you change anything in the slide section, it instantly updates all the view if you are in a collaborative view in your collabor online. How does it look? It looks scary. >> Very very scary. Uh so first of all uh it started because uh this feature [clears throat] was already part in in the PPT and we wanted to uh do the interop thing. So if we are bringing the PPT features uh to support the interopability why not to have it also in the ODF. So first of all uh in PPT they already had this this scary line is not so scary because it's always fixed. If you type this uh PPT knows that uh this is this entire section is about sections and then they are identified by this uh again huge number and uh [clears throat] and based on all this interop stuff we did something similar but we don't need a section identifier that fixed long string like this one here. This one is fixed always. But in our case, we we can just write this section to make life a little bit easier in our case. And then we have this long identifier. It's a go ID, but uh basically if you don't know what go I is, it's just a simple identifier, an ID and in that ID we store which slides are there and they are mapappable both ways. So slide has the data that which section they belong to and the section information has which slide they belong to. So you can map it either way and um basically that's it. It's it just looks scary when you see it the first time but otherwise it's just simple nested uh XML which is very readable in ODF files but uh not so readable in uh PPT uh and uh I'm just reading it right now. ODF ODF speak slide PBTX slide ID uh whatever I just said it's summarized there but um apart from that how does the UI look in the editor I have some screenshots there because I would have done the live demo but I have an extraordinary ability to uh make a perfectly stable software unworkable during the presentation so this time I'm just uh showing you the uh screenshots so if you want uh add a section. You just right click on it and you get this option. And if you click on the sections, you again get all these options of uh moving, renaming, remove just this section or slides and the section all together. And um you can rename it, you can collapse all all together to see what you are uh doing and the road map and stuff. And apart from that, another amazing feature we have in collabor online and kod is that you can now maximize the entire slide deck to see more slides all together and it also supports sections there. Isn't it beautiful? And I have worked on it. And basically this slide says that we have done our work and it works perfectly fine. Feel free to use it. And how does it work from uh core to browser? We have uno command slide sections and we just write uh all this detail in JSON form if you want name ID start index slide count if you want to uh play around with it and uh mostly that's it. Thank you. [applause]