[ramoneguru]

Nice work, did you start off by looking at any previously built canvas-like spreadsheets or was it straight to "virtualized custom canvas magic"?

I interviewed at a spreadsheet company (for a frontend role) and they asked, "how would you go about determining what cells need a border when a user clicks an individual cell, clicks a cell and selects multiple cells, clicks a cell next to an already selected cell." Fascinating problem and we talked about solutions for a little bit.

Noticed that you can't unselect a cell once it's selected? I'm on a Mac with Chrome (latest, no updates available).

Repo steps: 1. Select a few cells (⌘ + click) or an individual cell 2. Try unselecting (⌘ + click) those same cells clicked in #1 3. Cell is not unselected

[billylitt]

Row Zero frontend dev here -- when architecting, we looked at some off-the-shelf canvas-based table tools, but ultimately rolled our engine for more control & flexibility with our growing feature set. We elected for canvas over DOM for perf among other reasons (eg DOM scrollbar virtualization is hard when MAX_ROW * ROW_HEIGHT exceeds the maximum allowed browser element height).

Great interview question. Tons of nuance to drawing borders on adjacent cells, how to handle varying thickness, etc. Once you start looking closely, you notice the pixel differences between how this gets handled by various spreadsheeting tools.

Thanks for the report! This one's already on my list actually (selection negation & unique selection deduping) -- look for a fix soon.

[robbiejs]

Congrats on releasing the product! What are you using instead of the native scroll event of a browser element? Are you listener to `onwheel` events? Have you find a way to keep scrolling momentun scroll-browser/cross-device or do you normalize the delta to +1/-1?

I am the creator of DataGridXL (https://datagridxl.com), an Excel-like data grid component and it uses native scrolling. However, the document/sheet height/width is indeed limited by max div dimensions. Does your spreadsheet have a max?

[alooPotato]

Did you look at https://grid.glideapps.com/ by chance for rendering? Curious what it didn't support if you did.

[billylitt]

I don't remember looking at Glide, although it looks really nice & full-featured. I'll have to play around with it sometime. I do remember trying out https://www.npmjs.com/package/@deephaven/grid.

One pivotal feature that is difficult to map onto 3P tools is our data table UI, which is a separate scrollable grid that floats on top of the main sheet. That, combined with the complexity of formula selection, inserting buttons into cells (header dropdowns, filter, sort), led us to decide that rolling our own solution for full control was the right choice.