lock in

(the UI exists now. for real this time.)

hehe okay. LOCK IN.

this is the one where Penumbra stops being a really nice backend with no face and becomes an actual app you can look at. Slint UI, real components, and I wrote my own text editor because of course I did.so the editor. new crate, penumbra-editor. I could’ve just shoved a <textarea> equivalent in and called it a day but nooo, I wanted a proper block-based editor like the good note apps have. so it’s a document model made of blocks, each block has styled spans, and you edit it through commands: InsertText, DeleteRange, SplitBlock, MergeBlocks, SetMark, MoveCursor. every command goes through a Journal that’s just a command list + a pointer, which means undo/redo falls out for free (truncate on new push, walk the pointer back and forth). there’s a cursor/selection model and a view_model that snapshots the doc into something the UI can render without touching the guts. it’s BROKEN AND WEIRD NOW BUT IT’LL GET BETTER I PROMISE

the layout engine grew a CPU brain.

it was originally GPU-only via that vibe-graph-layout-gpu crate, which is great until you’re in an environment with no WebGPU (like… a lot of places, including some wasm setups) and then it just returns zero displacement and everything sits in a sad pile. so now there’s cpu.rs, my own Barnes-Hut quadtree force layout in plain Rust, and the engine tries GPU first and falls back to CPU when there’s no backend or the GPU step fails. no more “works on my machine with a discrete GPU only.” graceful degradation, hehe.

and then the actual Slint UI

which is the thing. it’s great.

it’s split into real components now: theme.slint for the tokens, top-bar.slint, map-canvas.slint for the graph, note-card.slint for the cards, editor-panel.slint for writing. app.slint wires it together. this is the part that broke my brain in Dioxus for literal months and in Slint it’s just… a file with a live preview and it looks how I tell it to. I keep waiting for the catch. haven’t hit it yet

tests too

NO JINXING ME (please)

I don’t want to jinx it but. this feels like the first time Penumbra is actually the thing I pictured back in that architecture-day devlog. backend I’m proud of, a UI that doesn’t fight me, my own editor, works on GPU or CPU, desktop or browser.

I locked in :3