Method getViewportStartLine

src/utils/Cursor.ts:172–184

(maxVisibleLines?: number)

  }

  getViewportStartLine(maxVisibleLines?: number): number {
    if (maxVisibleLines === undefined || maxVisibleLines <= 0) return 0
    const { line } = this.getPosition()
    const allLines = this.measuredText.getWrappedText()
    if (allLines.length <= maxVisibleLines) return 0
    const half = Math.floor(maxVisibleLines / 2)
    let startLine = Math.max(0, line - half)
    const endLine = Math.min(allLines.length, startLine + maxVisibleLines)
    if (endLine - startLine < maxVisibleLines) {
      startLine = Math.max(0, endLine - maxVisibleLines)
    }
    return startLine
  }

  getViewportCharOffset(maxVisibleLines?: number): number {
    const startLine = this.getViewportStartLine(maxVisibleLines)