xterm-cell-grid¶

Provenance¶

Source: .spec/spexcode/spec-cli/sessions/live-view/xterm-cell-grid/spec.md
Source SHA-256: a5564c7d90ad102d5ae3a110551e0c91a794b0be6b7dc391bda9a4cab71becde

xterm-cell-grid¶

The browser terminal is a cell grid, so renderer geometry comes from cells rather than an accumulated font measurement estimate. The pinned xterm DOM renderer measures glyphs to choose their internal letter spacing, but every emitted span also owns an explicit width equal to the cells represented by that span and clips ink to that box. A machine-specific CJK fallback face, font load, browser snap, or device-pixel ratio can therefore change ink inside a cell without shifting later cells or pushing the final glyphs through the row's right edge. Selection rebuilds the DOM rows through the same factory, so selected foreground spans retain those exact boxes; dragging cannot change glyph advance, hide the first selected cell, or perturb row layout.

The same version-locked, exact, idempotent installer used by [[xterm-sync-resize]] applies this upstream-sized correction. An unexpected xterm version or source shape fails installation. SpexCode does not reserve a guessed pixel gutter, remove a useful column, switch renderers by visibility, or patch glyphs by application or script. [[live-view]] owns the tmux/browser grid transaction and its real-browser evidence; this node owns the DOM renderer cell-box invariant.