TextBox

Use textbox when text must stay inside a known rectangle. It wraps deterministically and can shrink or truncate copy so agent-authored labels, callouts, and captions do not escape their boxes.

DSL example

elements: {
  summary: {
    id: 'summary',
    type: 'textbox',
    role: 'callout',
    layout: { x: 80, y: 120, width: 360, height: 140 },
    props: {
      type: 'textbox',
      x: 80,
      y: 120,
      width: 360,
      height: 140,
      content: 'TextBox wraps generated copy and keeps it within this visual region.',
      fontSize: 20,
      autoFit: 'shrink',
      background: { fill: '$surface', stroke: '$muted' },
    },
  },
}

Props

Prop	Type	Default	Description
x, y	number	required	Top-left corner of the box
width, height	number	required	Outer box dimensions
content	string	required	Text to display
padding	number | { x?: number; y?: number }	12, 10	Inner text inset
fontSize	number	20	Starting font size in pixels
minFontSize	number	10	Smallest font size used by autoFit: 'shrink'
fontFamily	string	'sans-serif'	Font family
fontWeight	string | number	'normal'	Font weight
lineHeight	number	1.2 * fontSize	Line height; values <= 4 are ratios
align	'start' | 'middle' | 'end'	'start'	Horizontal text alignment
verticalAlign	'top' | 'middle' | 'bottom'	'top'	Vertical placement of rendered lines
autoFit	'none' | 'shrink' | 'truncate'	'none'	How to handle text that exceeds the inner bounds
background	{ fill?: string; stroke?: string; strokeWidth?: number; radius?: number }	styled default	Background rectangle styling

Agent helper

Prefer createTextBoxPreset() or the CLI add-textbox command for generated prose:

npx @elucim/cli add-textbox diagram.elc --id summary --x 80 --y 120 --width 360 --height 140 --text "Bounded copy" --auto-fit shrink --background panel --out diagram.elc --json

Pass --background none when the text should be bounded for layout but drawn without a visible panel.

The helper and CLI default to autoFit: 'shrink' so generated copy stays bounded; the raw primitive defaults to autoFit: 'none'.