For my entry in the Flutter Clock Challenge I wanted to build something colorful, animated and playful that changes appearance with time. Ideally, I wanted it to look different every time I looked at it. I also wanted to explore the custom painting features of Flutter. 👨‍🎨

I ended up with an analog watch face featuring a simple particle system. It randomizes the color palettes while also maintaining legibility by calculating the luminance in real-time.

Building this was a bit of a struggle as I'm not very good with math, but the framework and the developer experience (hot reload, in particular) helped me out a lot. Being able to iterate quickly is a great way to learn new things. I guess the code could be improved in several ways, both in terms of elegance and performance. However, I've managed to easily stay far below the 16ms/frame benchmark (average 5ms/frame on my iPad while debugging). Flutter's rendering engine performs fantastically, even with my horrible math! 😅

Visit Ultimate Machine for a detailed write-up on how this was built.

• 🎨 Randomly selects color palettes while still maintaining legibility at all times.
• 🌤 Supports both light mode and dark mode, by filtering background color by luminance.
• 📱 Scales to fit the screen space available and adjust calculations & rendering accordingly.
• 🚀 At least 60 FPS on modern devices.
• 🌈 Constantly shifting and moving, making it fun to look at.

🎬 Watch it in action on Twitter 🎬

MIT License

Copyright (c) Mickel Andersson mickel@ultimatemachine.se (ultimatemachine.se & tayl.app)

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