Function resolvePatternFill

apps/sim/lib/pptx-renderer/renderer/style-resolver.ts:276–426

* Resolve ` ` into a CSS background value using repeating gradients. * * OOXML defines 40+ pattern presets. We support the most common ones and * fall back to a simple foreground/background 50% mix for unknown patterns.

(pattFill: SafeXmlNode, ctx: RenderContext)

 * fall back to a simple foreground/background 50% mix for unknown patterns.
 */
function resolvePatternFill(pattFill: SafeXmlNode, ctx: RenderContext): string {
  const preset = pattFill.attr('prst') ?? 'solid'

  // Foreground and background colors
  let fg = '#000000'
  let bg = '#ffffff'

  const fgClr = pattFill.child('fgClr')
  if (fgClr.exists()) {
    const { color, alpha } = resolveColor(fgClr, ctx)
    fg = toCssColor(color, alpha)
  }

  const bgClr = pattFill.child('bgClr')
  if (bgClr.exists()) {
    const { color, alpha } = resolveColor(bgClr, ctx)
    bg = toCssColor(color, alpha)
  }

  // Size of pattern tile in px
  const s = 8

  // Helper: returns CSS `background` shorthand with repeating pattern layer(s) over bg color.
  // Format: "<gradient-layer> 0 0/<size>, <bg-color-layer>"
  // This is a valid multi-layer CSS background shorthand.
  const pat = (gradient: string): string => `${gradient} 0 0/${s}px ${s}px, ${bg}`
  const pat2 = (g1: string, g2: string): string =>
    `${g1} 0 0/${s}px ${s}px, ${g2} 0 0/${s}px ${s}px, ${bg}`

  switch (preset) {
    // Solid fills
    case 'solid':
    case 'solidDmnd':
      return fg

    // Percentage fills (dots on background)
    case 'pct5':
    case 'pct10':
    case 'pct20':
    case 'pct25':
      return pat(`radial-gradient(${fg} 1px, transparent 1px)`)
    case 'pct30':
    case 'pct40':
    case 'pct50':
      return pat(`radial-gradient(${fg} 1.5px, transparent 1.5px)`)
    case 'pct60':
    case 'pct70':
    case 'pct75':
    case 'pct80':
    case 'pct90':
      return pat(`radial-gradient(${fg} 2.5px, transparent 2.5px)`)

    // Horizontal lines
    case 'horz':
    case 'ltHorz':
    case 'narHorz':
    case 'dkHorz':
      return pat(