Current design decisions for my game engine:
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First major task was getting a 3D viewport rendered by my engine into a Qt window. Qt is quite flexible and there were a lot of different avenues that seemed feasible for this. There were Most of them didn't work out in the end or were intended for different use cases.
What worked for me in the end was:
- Render viewport to an offscreen image
- Export the memory with "vkGetMemoryFdKHR"
- In Qt, create a VkImage and import the memory that was exported from the engine
- Extend QQuickItem and QSGTextureProvider to show the VkImage on a custom QML type window -
- Render viewport to an offscreen image
- Export the memory with "vkGetMemoryFdKHR"
- In Qt, create a VkImage and import the memory that was exported from the engine
- Extend QQuickItem and QSGTextureProvider to show the VkImage on a custom QML type windowThe reason for doing it in this roundabout way is that Qt uses its own Vulkan instance and device, and you can't just directly use images in one instance that were created by another one, even if you're in the same process.
I _could_ have told Qt to just use my Vulkan context for its own rendering, and I tried it and it technically worked, but that led to all sorts of synchronization issues and crashes.
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The reason for doing it in this roundabout way is that Qt uses its own Vulkan instance and device, and you can't just directly use images in one instance that were created by another one, even if you're in the same process.
I _could_ have told Qt to just use my Vulkan context for its own rendering, and I tried it and it technically worked, but that led to all sorts of synchronization issues and crashes.
Right now I _still_ get validation errors, but no crashes (until I close the window, probably because I do zero clean up currently :D)
So proof of concept for the most important aspect: done ✅
Next up: finding Qt libraries for some advanced UI stuff I wanna use.
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Right now I _still_ get validation errors, but no crashes (until I close the window, probably because I do zero clean up currently :D)
So proof of concept for the most important aspect: done ✅
Next up: finding Qt libraries for some advanced UI stuff I wanna use.
Most importantly: docking. My vision for the engine editor is that everything is a fully configurable and detachable dock. It should be able to spread over all your monitors!
Qt has built-in docking functionality, but it's restricted to QtWidgets (i.e. not available in QtQuick) and is a bit limited.
First library I looked at was Advanced Docking System for Qt: https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System
Seemed very promising but it doesn't have (and will never get) Wayland support, so not an option :/
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Most importantly: docking. My vision for the engine editor is that everything is a fully configurable and detachable dock. It should be able to spread over all your monitors!
Qt has built-in docking functionality, but it's restricted to QtWidgets (i.e. not available in QtQuick) and is a bit limited.
First library I looked at was Advanced Docking System for Qt: https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System
Seemed very promising but it doesn't have (and will never get) Wayland support, so not an option :/
Next most promising library: KDDockWidgets: https://github.com/KDAB/KDDockWidgets
Technically has QML support but I tried it and it doesn't seem to work well :/
The QtWidgets version of it is almost perfect, it does exactly what I want. Widgets isn't a deal breaker, I can just embed QtQuick views inside the docks (and using QML isn't _that_ important to me).
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Next most promising library: KDDockWidgets: https://github.com/KDAB/KDDockWidgets
Technically has QML support but I tried it and it doesn't seem to work well :/
The QtWidgets version of it is almost perfect, it does exactly what I want. Widgets isn't a deal breaker, I can just embed QtQuick views inside the docks (and using QML isn't _that_ important to me).
The thing is, the license of KDDockWidgets is GPL. Not LGPL, which means that if I use it the whole engine editor must be available under GPL if I understand correctly.
My current intention is to make it MIT, but I'm still open to the idea of putting it under the (L)GPL license. But I kinda want it to be my decision, not be forced by one dependency :/
Soo I'm not sure what to do. Guess I'll try out Qt's built-in docking first. Would prefer not to make my own system...
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The thing is, the license of KDDockWidgets is GPL. Not LGPL, which means that if I use it the whole engine editor must be available under GPL if I understand correctly.
My current intention is to make it MIT, but I'm still open to the idea of putting it under the (L)GPL license. But I kinda want it to be my decision, not be forced by one dependency :/
Soo I'm not sure what to do. Guess I'll try out Qt's built-in docking first. Would prefer not to make my own system...
The other major non-traditional UI type I need is a node/graph editor (like the one in Blender for materials / geometry nodes). I need it primarily for complex animation graphs, and I'd also like to use it for dialogue trees and maybe quest scripting.
Haven't tried it yet but QtNodes seems promising: https://github.com/paceholder/nodeeditor
It's also based on QtWidgets. Again, not a deal breaker, looks like I could embed it in QML if I wanted to.
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The other major non-traditional UI type I need is a node/graph editor (like the one in Blender for materials / geometry nodes). I need it primarily for complex animation graphs, and I'd also like to use it for dialogue trees and maybe quest scripting.
Haven't tried it yet but QtNodes seems promising: https://github.com/paceholder/nodeeditor
It's also based on QtWidgets. Again, not a deal breaker, looks like I could embed it in QML if I wanted to.
I wish the situation was reversed - making my own node editor system seems doable and maybe even fun, while making a flexible docking solution for an existing UI framework just feels annoying...
I wonder if it would be easiest to fork "Advanced Docking System for Qt" and add Wayland support 🤔 Tbf it does seem to work under XWayland already, but I feel like if I write new software it should try to support Wayland natively, even though it's a pain...
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I wish the situation was reversed - making my own node editor system seems doable and maybe even fun, while making a flexible docking solution for an existing UI framework just feels annoying...
I wonder if it would be easiest to fork "Advanced Docking System for Qt" and add Wayland support 🤔 Tbf it does seem to work under XWayland already, but I feel like if I write new software it should try to support Wayland natively, even though it's a pain...
Ok looks like the missing feature in Wayland which was blocking a fix for the advanced docking system has since been merged and this should be doable now. The maintainer isn't interested in Linux support but would be open to PRs.
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Ok looks like the missing feature in Wayland which was blocking a fix for the advanced docking system has since been merged and this should be doable now. The maintainer isn't interested in Linux support but would be open to PRs.
Alright I checked out the demo of Advanced Docking System and it also does exactly what I need, under a BSD license, as long you force it to run via X11/XWayland. I think I'll just go with this for now and if I _really_ need proper Wayland support I'll look into upstreaming a fix. And maybe someone else will do it until then :D
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Alright I checked out the demo of Advanced Docking System and it also does exactly what I need, under a BSD license, as long you force it to run via X11/XWayland. I think I'll just go with this for now and if I _really_ need proper Wayland support I'll look into upstreaming a fix. And maybe someone else will do it until then :D
I'm having Rust thoughts again. Somebody stop me please.
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I'm having Rust thoughts again. Somebody stop me please.
You know, if I really do end up using Qt for my game engine editor, maybe it'll land under the KDE umbrella one day 🤔 KameEngine
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You know, if I really do end up using Qt for my game engine editor, maybe it'll land under the KDE umbrella one day 🤔 KameEngine
Quick progress update:
- Implemented prototype of an input system (more on that when the details are clearer)
- Made a simple freefly camera controller with it
- Implemented the Pool/Handle system from the HypeHype talk ( https://mastodon.gamedev.place/@tracefree/115162926709506134 ) for meshes, textures, etc
- Worked around an issue in Qt Advanced Docking System, it's now the most viable option so next step will be making a simple editor -
Quick progress update:
- Implemented prototype of an input system (more on that when the details are clearer)
- Made a simple freefly camera controller with it
- Implemented the Pool/Handle system from the HypeHype talk ( https://mastodon.gamedev.place/@tracefree/115162926709506134 ) for meshes, textures, etc
- Worked around an issue in Qt Advanced Docking System, it's now the most viable option so next step will be making a simple editorDecided not to natively support Wayland for the engine editor for the time being, just via XWayland. I made an honest effort but I already spent more time on this than I did on setting up Vulkan to draw triangles and there's just one hindrance after another. There's extensions for most of them but they're either still planned or not widely adopted yet. With X11 it's way simpler to e.g. embed a window into another window as a dockable widget.
The game itself does support Wayland though.
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Decided not to natively support Wayland for the engine editor for the time being, just via XWayland. I made an honest effort but I already spent more time on this than I did on setting up Vulkan to draw triangles and there's just one hindrance after another. There's extensions for most of them but they're either still planned or not widely adopted yet. With X11 it's way simpler to e.g. embed a window into another window as a dockable widget.
The game itself does support Wayland though.
The good news is that I got Qt Advanced Docking System to work together with 3D viewports of my Vulkan engine just the way I had envisioned :D
So now I can finally focus more on editor features such as gizmos, scene tree editing, component inspectors, etc -
The good news is that I got Qt Advanced Docking System to work together with 3D viewports of my Vulkan engine just the way I had envisioned :D
So now I can finally focus more on editor features such as gizmos, scene tree editing, component inspectors, etcAlso I removed all QtQuick (Qt's more "browser-like" UI framework) dependencies for now. It seemed nice but two of the libraries I want to use are based on QtWidgets (a more traditional C++ framework) and I'd rather not mix and match unless I find a good reason for it.
This also simplifies viewports. I no longer export/import memory between two Vulkan instances and instead just embed my game's SDL window in a Qt dock widget.
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Also I removed all QtQuick (Qt's more "browser-like" UI framework) dependencies for now. It seemed nice but two of the libraries I want to use are based on QtWidgets (a more traditional C++ framework) and I'd rather not mix and match unless I find a good reason for it.
This also simplifies viewports. I no longer export/import memory between two Vulkan instances and instead just embed my game's SDL window in a Qt dock widget.
What makes a 3D editor a 3D editor? That's right, an infinite grid!
Implemented the shader from this excellent article by @bgolus: https://bgolus.medium.com/the-best-darn-grid-shader-yet-727f9278b9d8
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What makes a 3D editor a 3D editor? That's right, an infinite grid!
Implemented the shader from this excellent article by @bgolus: https://bgolus.medium.com/the-best-darn-grid-shader-yet-727f9278b9d8
Now with major and minor grid lines and colored x- and z- axes
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Now with major and minor grid lines and colored x- and z- axes
There's this philosophy that you should be very conservative with the C++ features you use, only use those that are at least a decade old, and that ideally you'd just write C.
I'm of the philosophy that I wanna see for myself if a feature is problematic, even if I might have to suffer the consequences.
Anyway last week I learned about C++ "concepts" and over the weekend I already found a use case for them. Terrible name but cool concept!
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There's this philosophy that you should be very conservative with the C++ features you use, only use those that are at least a decade old, and that ideally you'd just write C.
I'm of the philosophy that I wanna see for myself if a feature is problematic, even if I might have to suffer the consequences.
Anyway last week I learned about C++ "concepts" and over the weekend I already found a use case for them. Terrible name but cool concept!
In a similar vein, I tried out C++ modules in the previous iteration of the engine and learned first hand why people warn against them. No regrets though.
Gli ultimi otto messaggi ricevuti dalla Federazione
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Per il piano casa UE servono 150 miliardi all’anno. E una stretta sugli alloggi brevi (ma non sarà un divieto)
@news
https://www.eunews.it/2025/12/16/piano-casa-ue-jorgensen-affitti-brevi/
Il commissario UE Dan Jørgensen ha presentato a Strasburgo il piano della Commissione europea per affrontare la crisi abitativa. Prevista una revisione delle regole sugli aiuti di Stato e una semplificazione delle procedure per la costruzione di nuovi alloggi
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@steek_hutzee 29 marzo 2022, dunque dopo essere stati invasi e col rischio che le truppe russe arrivassero a Kiev. Ma perché vergognarsi?
Se ce l'avessi lungo 3 cm stimerei Rocco Siffredi
Se la mia donna fosse 1.40 m x 140 Kili invidierei Flavio Briatore
Se alle medie mi avessero bullizzato oggi avrei voluto essere un bullo come Trump e Putin
Nessuno ti giudica ma permettimi di non essere come te
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A Chrome extensions has been caught stealing prompts that users entered into AI chatbots
https://www.koi.ai/blog/urban-vpn-browser-extension-ai-conversations-data-collection
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@dougrutherford good luck!
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This is NOT an invitation to tell me your opinions about my weight, willpower, or to criticize my choice to go on this medication. Thank you.
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I'm on a glp-1 medication. It's... pretty wild.
I would describe myself as having a malfunctioning appetite: I am *always* ravenously hungry normally, which is one of the reasons I am always cutting up and eating apple slices and baby carrots at my desk, so that I don't overdo it. It's very exhausting to manage.
For the first time in decades I'm experiencing the sensation of fullness and not constantly thinking about food. Weight is dropping off fast, maybe even *too* fast. Wild.
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@informapirata @calamarim @eticadigitale una delle ragioni per la quale mi sono completamente staccato da Google. Server mio, decido io.
http://kerberos.archathome.eu/ho-mollato-google-foto-benvenuto-immich/
