///|
fn BpmnPaint::font_name(self : BpmnPaint, name : String) -> String {
  let result=StringBuilder(); result.write_char('"'); let mut units=1
  for c in name {
    let escaped=match c { '"' => "\\\""; '\\' => "\\\\"; '\n' => "\\a "; '\r' => "\\d "; _ => c.to_string() }
    if escaped.length() > self.limit-self.used-units-2-font_stack.length() { self.fail("bpmn/render-limit","Font metadata exceeds the output budget"); return "" }
    units+=escaped.length(); result.write_string(escaped)
  }
  result.write_string("\", "+font_stack); result.to_string()
}

///|
fn BpmnPaint::label(self : BpmnPaint, label : @bpmn_layout.Label) -> @writer.Node {
  let box=label.box
  let attrs=[("class","bpmn-label"),("data-owner",label.owner)]
  let raw=label.bounds
  let children=[]
  let text_children=[]
  if raw is Some(r) { children.push(self.rect(r.x.token,r.y.token,r.width.token,r.height.token,"none",fill=self.paint.color("bg"))) }
  else if label.mask { children.push(self.rect(bn(box.x),bn(box.y),bn(box.width),bn(box.height),"none",fill=self.paint.color("bg"))) }
  let x=box.x+box.width/2.0
  let lines=label.text.split("\n").to_array()
  let height=lines.length().to_double()*(label.size+4.0)
  let center_y=box.y+box.height/2.0
  let family=label.font.name.map(name => self.font_name(name)).unwrap_or(font_stack)
  let color=label.family.map(f => self.paint.color("\{f.name()}-ink")).unwrap_or(self.paint.color("text"))
  for i,line in lines {
    let y=center_y-height/2.0+label.size+i.to_double()*(label.size+4.0)
    let attrs=[("x",bn(x)),("y",bn(y)),("text-anchor","middle"),("font-family",family),("font-size",label.font.size.map(n => n.token).unwrap_or("13")),("font-weight",label.weight.to_string()),("fill",color)]
    if label.font.italic.unwrap_or(false) { attrs.push(("font-style","italic")) }
    if label.font.underline.unwrap_or(false) || label.font.strike_through.unwrap_or(false) { attrs.push(("text-decoration",(if label.font.underline.unwrap_or(false) { "underline " } else { "" })+(if label.font.strike_through.unwrap_or(false) { "line-through" } else { "" }))) }
    text_children.push(self.element("text",attrs~,children=[self.text(line.to_owned())]))
  }
  if label.rotation == -90 { children.push(self.element("g",attrs=[("transform","rotate(-90 \{bn(box.x+box.width/2.0)} \{bn(box.y+box.height/2.0)})")],children=text_children)) }
  else { children.append(text_children) }
  self.element("g",attrs~,children~)
}