Meeting at FrOSCon 2025 ======================= :Date: 2025-08-17 :Author: Benny Lyons and Hermann Voßeler :toc: Present:: - Wouter Verwijlen - Benny Lyons - Hermann Voßeler End goal:: To produce a design document. This Meeting is based on the document link:TODO[»Lumiera Workflow Proposals«] by Wouter Verwijlen. Wouter travelled to FrOSCon to meet the core team in person. This meeting discussed some central points of the planned workflow support in the Lumiera GUI. We discussed problems, agreed on various points and decided to produce a design document. Here we attempt to reconstruct and document the original meeting. Points discussed ---------------- We agreed upon the importance of a _Magnetic Timeline,_ as introduced by Final Cut X. However, our link:{ldoc}devel/rfc_final/ProcPlacementMetaphor.html[Placement concept (2008)] which predates FCPX's release,footnote:[Final Cut Pro X was link:https://en.wikipedia.org/wiki/Final_Cut_Pro#Final_Cut_Pro_X[released in 2011], and the »Magnetic Timeline« is generally considered a novel concept introduced with this update. The initial reception was rather controversial.] shares similar goals but its scope is more far-reaching. We consider _Magnetic Timeline_ to be an important advancement to legacy track oriented GUI schemes; but it is more mouse confined and does not support several Control Systems footnote:[The term »Control System« refers to one technical realisation of an human-computer-interface, which is used coherently and can coexist with other such interfaces -> link:{ldoc}/design/gui/InteractionControl.html#_foundation_concepts[more]. + The most relevant control systems are: Mouse, keyboard, pen, hardware controls, ...] on an equal footing, which is our vision. Modes, Tools and Views ~~~~~~~~~~~~~~~~~~~~~~ Modes are generally frowned upon in the User Interface Design discipline. On the other hand, they enjoy popularity in video editing applications. Tools and Views were introduced to improve the usability of Modes. We agreed to adopt tools as the more preferable system, but only if we manage to develop a suitable handling mechanism that can be used naturally throughout all Control Systems. Taking inspiration from Blender, _Hermann_ proposed a fundamental shift by extending the scope of tool usage to the entire UI. To do this, we agreed to introduce a top-level tool to navigate throughout the UI. _Wouter_ expressed some concerns on how effect parameters and mixer stripes could be accessed. This remains a problem to be resolved. We agreed that this default navigation tool should map down naturally to conventional usage of the mouse. We discussed that a consequence of that decision might be to introduce a special tool dedicated to dragging and moving clips, but we were concerned that such a mode might hamper fluid working with the UI. It seems preferable to introduce the moving of clips as a sub-mode into the navigation tool, with the option to lock moving of clips. _Wouter_ introduced a context sensitive tool palette which is rendered as an overlay in the timeline UI. The ability of Tools to support sub-modes is a simple extension of this proposal. With this functionality, it would be then be possible to switch between trim-, roll-, slide- and slip-edit after activating the edit tool. Similarly, the _gear switch_ as proposed in a previous online discussion would be integrated as a sub-mode if a user decided to manipulate any setting value. Internationalisation ~~~~~~~~~~~~~~~~~~~ The language of the UI is English. This does not mean that we exclude any language (all contributions are welcome). Certain words and terminology should never be translated, e.g., Track, Clip, Placement, ... . We also do not support translations that require a re-ordering of UI elements such as languages written right-to-left. This is due to priorities that we define. Unlimited Placement Constraints ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The use of fine-grained placement constraints is plagued with overwhelming the user with excessive relationships. This can be improved by using a small number of prototype set-ups: magnetic, relative and music anchored. Moreover, we require a diagnostic to reveal the reason why a given clip is positioned at where it is. .Routing _Hermann_ explained how the routing in Render Engine is based on Placements. All data streams are grouped according to the medium (video, audio,...) by default. Mixing-groups can be automatically established if resources are tagged. Layering order ~~~~~~~~~~~~~~ The layering order is usually arranged according to track sequence in the UI. To retain this configuration we would have to put some content into a track which can be located at a distance from other related content: not an ideal situation. One way to alleviate this problem is to allow the user to configure the layer ordering for a single track so that all content is always fixed to be above a reference clip. While this promises to be an interesting mechanism to improve the track sequence dilemma and provide the user a greater track arrangement freedom, further practical tests need to be carried out to determine its feasibility. Grouping Devices ~~~~~~~~~~~~~~~~ One idea presented in _Wouter_'s document was the introduction of a light-weight grouping device. This would solve some problems, for example, a number of objects can be collectively moved as one unit together. _Hermann_ proposed to use placements to achieve the same effect. It is yet to be resolved how this grouping can be visually represented. One important issue proposed by _Wouter_ was to use segments to arrange the narrative at the top level. To implement this feature would require on the one hand a considerable effort by developers, on the other hand, it does not naturally fit into the Lumiera core design as it would be a very specific extension instead of a homogeneous building block in Lumiera. _Hermann_ proposes to use nested sequences to implement this feature which is already been planned for the session model. All these nested sequences will have their own track structure, which is a tree relationship. For example, expanding one structure would not necessarily expand neighbouring structures. Another advantage of using this mechanism is that it can be used to construct a transition between adjacent chapters of a film while still retaining the ability to reshuffle chapters to explore various narratives. We can thus solve two problems with the same feature. _Wouter_ was concerned that it might be tedious to navigate between different chapters, especially if it is necessary to expand or collapse these elements repeatedly. One countermeasure to relieve constant opening and closing elements would be to expand the elements step wise while still retaining the ability to edit the contents. Target audience ~~~~~~~~~~~~~~~ It is important to identify our target audience to be able to obtain a clear vision of which features are more preferable to include and those features which might be less suitable to incorporate into Lumiera. This will allow us to fine-focus into the particular needs of these groups and provide us with a mechanism to curtail our long feature list. Eventually we might have a list of features ordered according to priority. Other factors are, of course, important in determining whether a feature is implemented or not, e.g., effort required to implement a feature; but we focus solely on identifying our target audience here. In his »Lumiera Workflow Proposals«, _Wouter_ identified five groups which mould most likely be attracted to Lumiera and its goals. - The highly specialised editor who works in an environment where different parts of the post-production of a film are handled by different people: assistant editors, colourists, audio engineers, etc. - The allround contracted editor who handles all aspects of post-production - The allround artistic filmmaker who also edits - The allround social media creator who values the use of visual effects, motion graphics and sound effects. - The free-flowing editor who does not have a fixed idea of how the edit should be and instead wants to play and move things around, and who might not work in a linear fashion: they might do a bit of colour correction to get a better sense of how a scene feels, then go back to editing, etc. - The editor who has the film already cut in their head and have a very strong sense of what they want to do and work in a very structured way towards accomplishing this vision. These groupings are naturally provisional and will mostly likely change -- which is very good -- as we add important features that are deemed essential but fit to no group in our selection. _Benny_ proposed to order these groups according to, in our opinion, those who would be most interested to those he would be less interested. In the following discussion, we identified the first group (the specialised editor within an industrial work environment) and also the social media creators to be a more challenging audience, since these require rather specialised tools to perform their tasks. Conclusions ----------- While we reached agreement in many points, the goal is to produce a design document for the GUI workflow. This task will require to spell out many details, thereby validating the viability of our ideas. - it remains to be shown that a generic _gesture concept_ can be mapped onto different control systems coherently - it is not clear yet to which extent it is possible to include other UI elements like the effect property settings into an overarching _navigation mode_ - a scheme must be worked out which allows to add a _placement prototype_ to each clip added to the timeline; furthermore we need to develop a representation that exposes the detailed _placement constraints_ in an understandable way - the proposed mechanism to control the layering order should be actually implemented and put into practical use to determine its feasibility - we need to consider in more detail how the proposed _light-weight grouping_ can be represented graphically and what actual features can be attached to such a new device. - a detailed analysis is required to establish gradual steps of expanding / collapsing, so that the overall timeline remains balanced and excess complexity can be hidden.