src/vs/editor/common/model/guidesTextModelPart.ts/GuidesTextModelPart/getVisibleColumnFromPosition
class GuidesTextModelPart:	private getVisibleColumnFromPosition(position: Position): number {
		return (
			CursorColumns.visibleColumnFromColumn(
				this.textModel.getLineContent(position.lineNumber),
				position.column,
				this.textModel.getOptions().tabSize
			) + 1
		);
	}