Merge pull request 'Refactor to integrate with CeTZ' functional API and shared-state' (#15) from feat/refactor-1 into dev

Reviewed-on: #15

src/cetz.typ

@@ -1 +1 @@
-#import "@preview/cetz:0.3.4": *
+#import "@preview/cetz:0.4.0": *

src/core/draw/delay.typ

@@ -0,0 +1,28 @@
+#import "/src/cetz.typ": draw
+
+#import "/src/core/utils.typ": get-ctx, set-ctx
+
+#let render(delay) = get-ctx(ctx => {
+  let y0 = ctx.y
+  let y1 = ctx.y - delay.size
+  for (i, line) in ctx.lifelines.enumerate() {
+    line.lines.push(("delay-start", y0))
+    line.lines.push(("delay-end", y1))
+    ctx.lifelines.at(i) = line
+  }
+  if delay.name != none {
+    let x0 = ctx.x-pos.first()
+    let x1 = ctx.x-pos.last()
+    draw.content(
+      ((x0 + x1) / 2, (y0 + y1) / 2),
+      anchor: "center",
+      delay.name
+    )
+  }
+  ctx.y = y1
+  set-ctx(c => {
+    c.y = ctx.y
+    c.lifelines = ctx.lifelines
+    return c
+  })
+})

src/core/draw/event.typ

@@ -0,0 +1,31 @@
+#import "/src/consts.typ": *
+#import "/src/core/utils.typ": get-ctx, set-ctx
+
+#let render(evt) = get-ctx(ctx => {
+  let par-name = evt.participant
+  let i = ctx.pars-i.at(par-name)
+  let par = ctx.participants.at(i)
+  let line = ctx.lifelines.at(i)
+  let entry = (evt.event, ctx.y)
+
+  if evt.event == "disable" {
+    line.level -= 1
+  } else if evt.event == "enable" {
+    line.level += 1
+    entry.push(evt.lifeline-style)
+  } else if evt.event == "create" {
+    ctx.y -= CREATE-OFFSET
+    entry.at(1) = ctx.y
+    (par.draw)(par, y: ctx.y)
+  } else if evt.event == "destroy" {
+  } else {
+    panic("Unknown event '" + evt.event + "'")
+  }
+
+  line.lines.push(entry)
+  set-ctx(c => {
+    c.lifelines.at(i) = line
+    c.y = ctx.y
+    return c
+  })
+})

src/core/draw/group.typ

@@ -0,0 +1,117 @@
+#import "/src/cetz.typ": draw
+
+#import "/src/consts.typ": *
+#import "/src/core/utils.typ": get-ctx, set-ctx
+
+#let render-start(grp) = get-ctx(ctx => {
+  let grp = grp
+  ctx.y -= Y-SPACE
+  let m = measure(
+    box(
+      grp.name,
+      inset: (
+        left: 5pt,
+        right: 5pt,
+        top: 3pt,
+        bottom: 3pt
+      ),
+    )
+  )
+  ctx.groups = ctx.groups.map(g => {
+    if g.at(1).min-i == grp.min-i { g.at(2) += 1 }
+    if g.at(1).max-i == grp.max-i { g.at(3) += 1 }
+    g
+  })
+  if grp.grp-type == "alt" {
+    grp.insert("elses", ())
+  }
+  ctx.groups.push((ctx.y, grp, 0, 0))
+  ctx.y -= m.height / 1pt
+
+  set-ctx(c => {
+    c.y = ctx.y
+    c.groups = ctx.groups
+    return c
+  })
+})
+
+
+#let draw-group(x0, x1, y0, y1, group) = {
+  let name = text(group.name, weight: "bold")
+  let m = measure(box(name))
+  let w = m.width / 1pt + 15
+  let h = m.height / 1pt + 6
+  draw.rect(
+    (x0, y0),
+    (x1, y1)
+  )
+  draw.line(
+    (x0, y0),
+    (x0 + w, y0),
+    (x0 + w, y0 - h / 2),
+    (x0 + w - 5, y0 - h),
+    (x0, y0 - h),
+    fill: COL-GRP-NAME,
+    close: true
+  )
+  draw.content(
+    (x0, y0),
+    name,
+    anchor: "north-west",
+    padding: (left: 5pt, right: 10pt, top: 3pt, bottom: 3pt)
+  )
+
+  if group.desc != none {
+    draw.content(
+      (x0 + w, y0),
+      text([\[#group.desc\]], weight: "bold", size: .8em),
+      anchor: "north-west",
+      padding: 3pt
+    )
+  }
+}
+
+#let draw-else(x0, x1, y, elmt) = {
+  draw.line(
+    (x0, y),
+    (x1, y),
+    stroke: (dash: (2pt, 1pt), thickness: .5pt)
+  )
+  draw.content(
+    (x0, y),
+    text([\[#elmt.desc\]], weight: "bold", size: .8em),
+    anchor: "north-west",
+    padding: 3pt
+  )
+}
+
+#let render-end(group) = get-ctx(ctx => {
+  ctx.y -= Y-SPACE
+  let (start-y, group, start-lvl, end-lvl) = ctx.groups.pop()
+  let x0 = ctx.x-pos.at(group.min-i) - start-lvl * 10 - 20
+  let x1 = ctx.x-pos.at(group.max-i) + end-lvl * 10 + 20
+  
+  draw-group(x0, x1, start-y, ctx.y, group)
+
+  if group.grp-type == "alt" {
+    for (else-y, else-elmt) in group.elses {
+      draw-else(x0, x1, else-y, else-elmt)
+    }
+  }
+
+  set-ctx(c => {
+    c.y = ctx.y
+    c.groups = ctx.groups
+    return c
+  })
+})
+
+#let render-else(else_) = set-ctx(ctx => {
+  ctx.y -= Y-SPACE
+  let m = measure(text([\[#else_.desc\]], weight: "bold", size: .8em))
+  ctx.groups.last().at(1).elses.push((
+    ctx.y, else_
+  ))
+  ctx.y -= m.height / 1pt
+  return ctx
+})

src/core/draw/note.typ

@@ -0,0 +1,163 @@
+#import "/src/cetz.typ": draw
+
+#import "/src/consts.typ": *
+#import "/src/core/utils.typ": get-ctx, set-ctx
+
+#let get-size(note) = {
+  let PAD = if note.shape == "hex" {NOTE-HEX-PAD} else {NOTE-PAD}
+  let m = measure(box(note.content))
+  let w = m.width / 1pt + PAD.last() * 2
+  let h = m.height / 1pt + PAD.first() * 2
+  if note.shape == "default" {
+    w += NOTE-CORNER-SIZE
+  }
+  return (
+    width: w,
+    height: h
+  )
+}
+
+#let get-base-x(pars-i, x-pos, note) = {
+  if note.side == "across" {
+    return (x-pos.first() + x-pos.last()) / 2
+  }
+  if note.side == "over" {
+    if type(note.pos) == array {
+      let xs = note.pos.map(par => x-pos.at(pars-i.at(par)))
+      return (calc.min(..xs) + calc.max(..xs)) / 2
+    }
+  }
+  return x-pos.at(pars-i.at(note.pos))
+}
+
+#let get-box(note) = {
+  let PAD = if note.shape == "hex" {NOTE-HEX-PAD} else {NOTE-PAD}
+  let inset = (
+    left: PAD.last() * 1pt,
+    right: PAD.last() * 1pt,
+    top: PAD.first() * 1pt,
+    bottom: PAD.first() * 1pt,
+  )
+  if note.shape == "default" {
+    inset.right += NOTE-CORNER-SIZE * 1pt
+  }
+  if note.side == "left" {
+    inset.right += NOTE-GAP * 1pt
+  } else if note.side == "right" {
+    inset.left += NOTE-GAP * 1pt
+  }
+  return box(note.content, inset: inset)
+}
+
+#let render(note, y: auto, forced: false) = {
+  if not note.linked {
+    if not note.aligned {
+      set-ctx(c => {
+        c.y -= Y-SPACE
+        return c
+      })
+    }
+  } else if not forced {
+    return ()
+  }
+
+  get-ctx(ctx => {
+    let y = y
+    if y == auto {
+      y = ctx.y
+    }
+    
+
+    let PAD = if note.shape == "hex" {NOTE-HEX-PAD} else {NOTE-PAD}
+    let m = measure(box(note.content))
+    let w = m.width / 1pt + PAD.last() * 2
+    let h = m.height / 1pt + PAD.first() * 2
+    let total-w = w
+    if note.shape == "default" {
+      total-w += NOTE-CORNER-SIZE
+    }
+
+    let base-x = get-base-x(ctx.pars-i, ctx.x-pos, note)
+
+    let i = none
+    if note.pos != none and type(note.pos) == str {
+      i = ctx.pars-i.at(note.pos)
+    }
+    let x0 = base-x
+    if note.side == "left" {
+      x0 -= NOTE-GAP
+      x0 -= total-w
+      if ctx.lifelines.at(i).level != 0 {
+        x0 -= LIFELINE-W / 2
+      }
+    } else if note.side == "right" {
+      x0 += NOTE-GAP
+      x0 += ctx.lifelines.at(i).level * LIFELINE-W / 2
+    } else if note.side == "over" or note.side == "across" {
+      x0 -= total-w / 2
+    }
+
+    let x1 = x0 + w
+    let x2 = x0 + total-w
+    let y0 = y
+
+    if note.linked {
+      y0 += h / 2
+    }
+    let y1 = y0 - h
+
+    if note.shape == "default" {
+      draw.line(
+        (x0, y0),
+        (x1, y0),
+        (x2, y0 - NOTE-CORNER-SIZE),
+        (x2, y1),
+        (x0, y1),
+        stroke: black + .5pt,
+        fill: note.color,
+        close: true
+      )
+      draw.line(
+        (x1, y0),
+        (x1, y0 - NOTE-CORNER-SIZE),
+        (x2, y0 - NOTE-CORNER-SIZE),
+        stroke: black + .5pt
+      )
+    } else if note.shape == "rect" {
+      draw.rect(
+        (x0, y0),
+        (x2, y1),
+        stroke: black + .5pt,
+        fill: note.color
+      )
+    } else if note.shape == "hex" {
+      let lx = x0 + PAD.last()
+      let rx = x2 - PAD.last()
+      let my = (y0 + y1) / 2
+      draw.line(
+        (lx, y0),
+        (rx, y0),
+        (x2, my),
+        (rx, y1),
+        (lx, y1),
+        (x0, my),
+        stroke: black + .5pt,
+        fill: note.color,
+        close: true
+      )
+    }
+
+    draw.content(
+      ((x0 + x1)/2, (y0 + y1)/2),
+      note.content,
+      anchor: "center"
+    )
+
+    if note.aligned-with == none and (note.pos != none or note.side == "across") {
+      set-ctx(c => {
+        c.y -= h
+        return c
+      })
+    }
+  })
+}

src/core/draw/participant.typ

@@ -0,0 +1,406 @@
+#import "/src/cetz.typ": draw
+
+#import "/src/consts.typ": *
+#import "/src/core/utils.typ": get-ctx, get-style, set-ctx
+
+#let get-size(par) = {
+  if par.invisible {
+    return (width: 0pt, height: 0pt)
+  }
+  let m = measure(box(par.display-name))
+  let w = m.width
+  let h = m.height
+  let (shape-w, shape-h) = (
+    participant: (w + PAR-PAD.last() * 2, h + PAR-PAD.first() * 2),
+    actor: (ACTOR-WIDTH * 1pt, ACTOR-WIDTH * 2pt + SYM-GAP * 1pt + h),
+    boundary: (BOUNDARY-HEIGHT * 2pt, BOUNDARY-HEIGHT * 1pt + SYM-GAP * 1pt + h),
+    control: (CONTROL-HEIGHT * 1pt, CONTROL-HEIGHT * 1pt + SYM-GAP * 1pt + h),
+    entity: (ENTITY-HEIGHT * 1pt, ENTITY-HEIGHT * 1pt + 2pt + SYM-GAP * 1pt + h),
+    database: (DATABASE-WIDTH * 1pt, DATABASE-WIDTH * 4pt / 3 + SYM-GAP * 1pt + h),
+    collections: (
+      w + COLLECTIONS-PAD.last() * 2 + calc.abs(COLLECTIONS-DX) * 1pt,
+      h + COLLECTIONS-PAD.first() * 2 + calc.abs(COLLECTIONS-DY) * 1pt,
+    ),
+    queue: (
+      w + QUEUE-PAD.last() * 2 + 3 * (h + QUEUE-PAD.first() * 2) / 4,
+      h + QUEUE-PAD.first() * 2
+    ),
+    custom: (
+      measure(par.custom-image).width,
+      measure(par.custom-image).height + SYM-GAP * 1pt + h
+    )
+  ).at(par.shape)
+
+  return (
+    width: calc.max(w, shape-w),
+    height: calc.max(h, shape-h)
+  )
+}
+
+#let _render-participant(x, y, p, m, bottom) = {
+  let w = m.width / 1pt
+  let h = m.height / 1pt
+  let x0 = x - w / 2 - PAR-PAD.last() / 1pt
+  let x1 = x + w / 2 + PAR-PAD.last() / 1pt
+  let y0 = y + h + PAR-PAD.first() / 1pt * 2
+  if bottom {
+    y0 = y
+  }
+  let y1 = y0 - h - PAR-PAD.first() / 1pt * 2
+
+  draw.rect(
+    (x0, y0),
+    (x1, y1),
+    radius: 2pt,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.content(
+    ((x0 + x1) / 2, (y0 + y1) / 2),
+    p.display-name,
+    anchor: "center"
+  )
+}
+
+#let _render-actor(x, y, p, m, bottom) = {
+  let w2 = ACTOR-WIDTH / 2
+  let head-r = ACTOR-WIDTH / 4
+  let height = ACTOR-WIDTH * 2
+  let arms-y = height * 0.375
+
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + height + SYM-GAP}
+  draw.circle(
+    (x, y0 - head-r),
+    radius: head-r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.line((x, y0 - head-r * 2), (x, y0 - height + w2), stroke: black + .5pt)
+  draw.line((x - w2, y0 - arms-y), (x + w2, y0 - arms-y), stroke: black + .5pt)
+  draw.line((x - w2, y0 - height), (x, y0 - height + w2), (x + w2, y0 - height), stroke: black + .5pt)
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-boundary(x, y, p, m, bottom) = {
+  let circle-r = BOUNDARY-HEIGHT / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + BOUNDARY-HEIGHT + SYM-GAP}
+  let x0 = x - BOUNDARY-HEIGHT
+  let y1 = y0 - circle-r
+  let y2 = y0 - BOUNDARY-HEIGHT
+
+  draw.circle(
+    (x + circle-r, y1),
+    radius: circle-r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.line(
+    (x0, y0), (x0, y2),
+    stroke: black + .5pt
+  )
+  draw.line(
+    (x0, y1), (x, y1),
+    stroke: black + .5pt
+  )
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-control(x, y, p, m, bottom) = {
+  let r = CONTROL-HEIGHT / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + CONTROL-HEIGHT + SYM-GAP}
+
+  draw.circle(
+    (x, y0 - r),
+    radius: r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.mark((x, y0), (x - r / 2, y0), symbol: "stealth", fill: black)
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-entity(x, y, p, m, bottom) = {
+  let r = ENTITY-HEIGHT / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + ENTITY-HEIGHT + SYM-GAP}
+  let y1 = y0 - ENTITY-HEIGHT - 1.5
+
+  draw.circle(
+    (x, y0 - r),
+    radius: r,
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.line(
+    (x - r, y1),
+    (x + r, y1),
+    stroke: black + .5pt
+  )
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-database(x, y, p, m, bottom) = {
+  let height = DATABASE-WIDTH * 4 / 3
+  let rx = DATABASE-WIDTH / 2
+  let ry = rx / 2
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + height + SYM-GAP}
+  let y1 = y0 - height
+
+  draw.merge-path(
+    close: true,
+    fill: p.color,
+    stroke: black + .5pt,
+    {
+      draw.bezier((x - rx, y0 - ry), (x, y0), (x - rx, y0 - ry/2), (x - rx/2, y0))
+      draw.bezier((), (x + rx, y0 - ry), (x + rx/2, y0), (x + rx, y0 - ry/2))
+      draw.line((), (x + rx, y1 + ry))
+      draw.bezier((), (x, y1), (x + rx, y1 + ry/2), (x + rx/2, y1))
+      draw.bezier((), (x - rx, y1 + ry), (x - rx/2, y1), (x - rx, y1 + ry/2))
+    }
+  )
+  draw.merge-path(
+    stroke: black + .5pt,
+    {
+      draw.bezier((x - rx, y0 - ry), (x, y0 - ry*2), (x - rx, y0 - 3*ry/2), (x - rx/2, y0 - ry*2))
+      draw.bezier((), (x + rx, y0 - ry), (x + rx/2, y0 - ry*2), (x + rx, y0 - 3*ry/2))
+    }
+  )
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let _render-collections(x, y, p, m, bottom) = {
+  let w = m.width / 1pt
+  let h = m.height / 1pt
+  let dx = COLLECTIONS-DX
+  let dy = COLLECTIONS-DY
+  let total-w = w + PAR-PAD.last() * 2 / 1pt + calc.abs(dx)
+  let total-h = h + PAR-PAD.first() * 2 / 1pt + calc.abs(dy)
+
+  let x0 = x - total-w / 2
+  let x1 = x0 + calc.abs(dx)
+  let x3 = x0 + total-w
+  let x2 = x3 - calc.abs(dx)
+  
+  let y0 = if bottom {y} else {y + total-h}
+  let y1 = y0 - calc.abs(dy)
+  let y3 = y0 - total-h
+  let y2 = y3 + calc.abs(dy)
+
+  let r1 = (x1, y0, x3, y2)
+  let r2 = (x0, y1, x2, y3)
+
+  if dx < 0 {
+    r1.at(0) = x0
+    r1.at(2) = x2
+    r2.at(0) = x1
+    r2.at(2) = x3
+  }
+
+  if dy < 0 {
+    r1.at(1) = y1
+    r1.at(3) = y3
+    r2.at(1) = y0
+    r2.at(3) = y2
+  }
+  draw.rect(
+    (r1.at(0), r1.at(1)),
+    (r1.at(2), r1.at(3)),
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  draw.rect(
+    (r2.at(0), r2.at(1)),
+    (r2.at(2), r2.at(3)),
+    fill: p.color,
+    stroke: black + .5pt
+  )
+  
+  draw.content(
+    ((r2.at(0) + r2.at(2)) / 2, (r2.at(1) + r2.at(3)) / 2),
+    p.display-name,
+    anchor: "center"
+  )
+}
+
+#let _render-queue(x, y, p, m, bottom) = {
+  let w = (m.width + QUEUE-PAD.last() * 2) / 1pt
+  let h = (m.height + QUEUE-PAD.first() * 2) / 1pt
+  let total-h = h
+  let ry = total-h / 2
+  let rx = ry / 2
+  let total-w = w + 3 + 3 * rx
+
+  let x0 = x - total-w / 2
+  let y0 = if bottom {y} else {y + total-h}
+  let y1 = y0 - total-h
+  let x-left = x0 + rx
+  let x-right = x-left + w + rx
+  draw.merge-path(
+    close: true,
+    fill: p.color,
+    stroke: black + .5pt,
+    {
+      draw.bezier((x-right, y0), (x-right + rx, y0 - ry), (x-right + rx/2, y0), (x-right + rx, y0 - ry/2))
+      draw.bezier((), (x-right, y1), (x-right + rx, y1 + ry/2), (x-right + rx/2, y1))
+      draw.line((), (x-left, y1))
+      draw.bezier((), (x-left - rx, y0 - ry), (x-left - rx/2, y1), (x-left - rx, y1 + ry/2))
+      draw.bezier((), (x-left, y0), (x-left - rx, y0 - ry/2), (x-left - rx/2, y0))
+    }
+  )
+  draw.merge-path(
+    stroke: black + .5pt,
+    {
+      draw.bezier((x-right, y0), (x-right - rx, y0 - ry), (x-right - rx/2, y0), (x-right - rx, y0 - ry/2))
+      draw.bezier((), (x-right, y1), (x-right - rx, y1 + ry/2), (x-right - rx/2, y1))
+    }
+  )
+  draw.content(
+    ((x-left + x-right - rx) / 2, y0 - ry),
+    p.display-name,
+    anchor: "center"
+  )
+}
+
+#let _render-custom(x, y, p, m, bottom) = {
+  let image-m = measure(p.custom-image)
+  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + image-m.height / 1pt + SYM-GAP}
+  draw.content((x - image-m.width / 2pt, y0), p.custom-image, anchor: "north-west")
+  draw.content(
+    (x, y),
+    p.display-name,
+    anchor: if bottom {"north"} else {"south"}
+  )
+}
+
+#let render(par, y: 0, bottom: false) = draw.group(cetz-ctx => {
+  let ctx = cetz-ctx.shared-state.chronos
+  let m = measure(box(par.display-name))
+  let func = (
+    participant: _render-participant,
+    actor: _render-actor,
+    boundary: _render-boundary,
+    control: _render-control,
+    entity: _render-entity,
+    database: _render-database,
+    collections: _render-collections,
+    queue: _render-queue,
+    custom: _render-custom,
+  ).at(par.shape)
+  func(ctx.x-pos.at(par.i), y, par, m, bottom)
+},)
+
+#let render-lifelines() = get-ctx(ctx => {
+  let participants = ctx.participants
+  for p in participants.filter(p => not p.invisible) {
+    let x = ctx.x-pos.at(p.i)
+
+    // Draw vertical line
+    let last-y = 0
+
+    let rects = ()
+    let destructions = ()
+    let lines = ()
+
+    // Compute lifeline rectangles + destruction positions
+    for line in ctx.lifelines.at(p.i).lines {
+      let event = line.first()
+      if event == "create" {
+        last-y = line.at(1)
+
+      } else if event == "enable" {
+        if lines.len() == 0 {
+          draw.line(
+            (x, last-y),
+            (x, line.at(1)),
+            stroke: p.line-stroke
+          )
+        }
+        lines.push(line)
+      
+      } else if event == "disable" or event == "destroy" {
+        let lvl = 0
+        if lines.len() != 0 {
+          let l = lines.pop()
+          lvl = lines.len()
+          rects.push((
+            x + lvl * LIFELINE-W / 2,
+            l.at(1),
+            line.at(1),
+            l.at(2)
+          ))
+          last-y = line.at(1)
+        }
+
+        if event == "destroy" {
+          destructions.push((x + lvl * LIFELINE-W / 2, line.at(1)))
+        }
+      } else if event == "delay-start" {
+        draw.line(
+          (x, last-y),
+          (x, line.at(1)),
+          stroke: p.line-stroke
+        )
+        last-y = line.at(1)
+      } else if event == "delay-end" {
+        draw.line(
+          (x, last-y),
+          (x, line.at(1)),
+          stroke: (
+            dash: "loosely-dotted",
+            paint: gray.darken(40%),
+            thickness: .8pt
+          )
+        )
+        last-y = line.at(1)
+      }
+    }
+
+    draw.line(
+      (x, last-y),
+      (x, ctx.y),
+      stroke: p.line-stroke
+    )
+
+    // Draw lifeline rectangles (reverse for bottom to top)
+    for rect in rects.rev() {
+      let (cx, y0, y1, style) = rect
+      let style = get-style("lifeline", style)
+      draw.rect(
+        (cx - LIFELINE-W / 2, y0),
+        (cx + LIFELINE-W / 2, y1),
+        ..style
+      )
+    }
+
+    // Draw lifeline destructions
+    for dest in destructions {
+      let (cx, cy) = dest
+      draw.line((cx - 8, cy - 8), (cx + 8, cy + 8), stroke: COL-DESTRUCTION + 2pt)
+      draw.line((cx - 8, cy + 8), (cx + 8, cy - 8), stroke: COL-DESTRUCTION + 2pt)
+    }
+
+    // Draw participants (end)
+    if p.show-bottom {
+      (p.draw)(p, y: ctx.y, bottom: true)
+    }
+  }
+},)

src/core/draw/separator.typ

@@ -0,0 +1,47 @@
+#import "/src/cetz.typ": draw
+
+#import "/src/consts.typ": *
+#import "/src/core/utils.typ": get-ctx, set-ctx
+
+#let render(sep) = get-ctx(ctx => {
+  ctx.y -= Y-SPACE
+
+  let x0 = ctx.x-pos.first() - 20
+  let x1 = ctx.x-pos.last() + 20
+  let m = measure(
+    box(
+      sep.name,
+      inset: (left: 3pt, right: 3pt, top: 5pt, bottom: 5pt)
+    )
+  )
+  let w = m.width / 1pt
+  let h = m.height / 1pt
+  let cx = (x0 + x1) / 2
+  let xl = cx - w / 2
+  let xr = cx + w / 2
+
+  ctx.y -= h / 2
+  draw.rect(
+    (x0, ctx.y),
+    (x1, ctx.y - 3),
+    stroke: none,
+    fill: white
+  )
+  draw.line((x0, ctx.y), (x1, ctx.y))
+  ctx.y -= 3
+  draw.line((x0, ctx.y), (x1, ctx.y))
+  draw.content(
+    ((x0 + x1) / 2, ctx.y + 1.5),
+    sep.name,
+    anchor: "center",
+    padding: (5pt, 3pt),
+    frame: "rect",
+    fill: COL-SEP-NAME
+  )
+  ctx.y -= h / 2
+
+  set-ctx(c => {
+    c.y = ctx.y
+    return c
+  })
+})

src/core/draw/sequence.typ

@@ -0,0 +1,361 @@
+#import "/src/cetz.typ": draw, vector
+
+#import "note.typ"
+#import "/src/consts.typ": *
+#import "/src/core/utils.typ": get-ctx, set-ctx
+
+#let get-arrow-marks(sym, color) = {
+  if sym == none {
+    return none
+  }
+  if type(sym) == array {
+    return sym.map(s => get-arrow-marks(s, color))
+  }
+  (
+    "": none,
+    ">": (symbol: ">", fill: color),
+    ">>": (symbol: "straight"),
+    "\\": (symbol: ">", fill: color, harpoon: true),
+    "\\\\": (symbol: "straight", harpoon: true),
+    "/": (symbol: ">", fill: color, harpoon: true, flip: true),
+    "//": (symbol: "straight", harpoon: true, flip: true),
+    "x": none,
+    "o": none,
+  ).at(sym)
+}
+
+#let reverse-arrow-mark(mark) = {
+  if type(mark) == array {
+    return mark.map(m => reverse-arrow-mark(m))
+  }
+  let mark2 = mark
+  if type(mark) == dictionary and mark.at("harpoon", default: false) {
+    let flipped = mark.at("flip", default: false)
+    mark2.insert("flip", not flipped)
+  }
+  return mark2
+}
+
+#let is-tip-of-type(type_, tip) = {
+  if type(tip) == str and tip == type_ {
+    return true
+  }
+  if type(tip) == array and tip.contains(type_) {
+    return true
+  }
+  return false
+}
+#let is-circle-tip = is-tip-of-type.with("o")
+#let is-cross-tip = is-tip-of-type.with("x")
+
+#let render(seq) = get-ctx(ctx => {
+  ctx.y -= Y-SPACE
+
+  let i1 = ctx.pars-i.at(seq.p1)
+  let i2 = ctx.pars-i.at(seq.p2)
+  let width = calc.abs(ctx.x-pos.at(i1) - ctx.x-pos.at(i2))
+
+  let h = 0
+  let comment = if seq.comment == none {none} else {
+    let w = calc.min(width * 1pt, measure(seq.comment).width)
+    box(
+      width: if i1 == i2 {auto} else {w},
+      seq.comment
+    )
+  }
+  // Reserve space for comment
+  if comment != none {
+    h = calc.max(h, measure(comment).height / 1pt + 6)
+  }
+  if "linked-note" in seq {
+    h = calc.max(h, note.get-size(seq.linked-note).height / 2)
+  }
+  ctx.y -= h
+
+  let start-info = (
+    i: i1,
+    x: ctx.x-pos.at(i1),
+    y: ctx.y,
+    ll-lvl: ctx.lifelines.at(i1).level * LIFELINE-W / 2
+  )
+  let end-info = (
+    i: i2,
+    x: ctx.x-pos.at(i2),
+    y: ctx.y,
+    ll-lvl: ctx.lifelines.at(i2).level * LIFELINE-W / 2
+  )
+  let slant = if seq.slant == auto {
+    DEFAULT-SLANT
+  } else if seq.slant != none {
+    seq.slant
+  } else {
+    0
+  }
+  end-info.y -= slant
+  if seq.p1 == seq.p2 {
+    end-info.y -= 10
+  }
+
+  if seq.disable-src {
+    let src-line = ctx.lifelines.at(i1)
+    src-line.level -= 1
+    src-line.lines.push(("disable", start-info.y))
+    ctx.lifelines.at(i1) = src-line
+  }
+  if seq.destroy-src {
+    let src-line = ctx.lifelines.at(i1)
+    src-line.lines.push(("destroy", start-info.y))
+    ctx.lifelines.at(i1) = src-line
+  }
+  if seq.disable-dst {
+    let dst-line = ctx.lifelines.at(i2)
+    dst-line.level -= 1
+    dst-line.lines.push(("disable", end-info.y))
+    ctx.lifelines.at(i2) = dst-line
+  }
+  if seq.destroy-dst {
+    let dst-line = ctx.lifelines.at(i2)
+    dst-line.lines.push(("destroy", end-info.y))
+    ctx.lifelines.at(i2) = dst-line
+  }
+  if seq.enable-dst {
+    let dst-line = ctx.lifelines.at(i2)
+    dst-line.level += 1
+    ctx.lifelines.at(i2) = dst-line
+  }
+  if seq.create-dst {
+    let par = ctx.participants.at(i2)
+    let m = measure(box(par.display-name))
+    let f = if i1 > i2 {-1} else {1}
+    end-info.x -= (m.width + PAR-PAD.last() * 2) / 2pt * f
+    (par.draw)(par, y: end-info.y)
+  }
+
+  end-info.ll-lvl = ctx.lifelines.at(i2).level * LIFELINE-W / 2
+
+  // Compute left/right position at start/end
+  start-info.insert("lx", start-info.x)
+  if start-info.ll-lvl != 0 { start-info.lx -= LIFELINE-W / 2 }
+  end-info.insert("lx", end-info.x)
+  if end-info.ll-lvl != 0 { end-info.lx -= LIFELINE-W / 2 }
+
+  start-info.insert("rx", start-info.x + start-info.ll-lvl)
+  end-info.insert("rx", end-info.x + end-info.ll-lvl)
+
+  // Choose correct points to link
+  let x1 = start-info.rx
+  let x2 = end-info.lx
+
+  if (start-info.i > end-info.i) {
+    x1 = start-info.lx
+    x2 = end-info.rx
+  }
+
+  let style = (
+    mark: (
+      start: get-arrow-marks(seq.start-tip, seq.color),
+      end: get-arrow-marks(seq.end-tip, seq.color),
+      scale: 1.2
+    ),
+    stroke: (
+      dash: if seq.dashed {(2pt,2pt)} else {"solid"},
+      paint: seq.color,
+      thickness: .5pt
+    )
+  )
+
+  let y0 = start-info.y
+  if "linked-note" in seq {
+    // TODO: adapt note.render
+    (seq.linked-note.draw)(seq.linked-note, y: start-info.y, forced: true)
+  }
+
+  let flip-mark = end-info.i <= start-info.i
+  if seq.flip {
+    flip-mark = not flip-mark
+  }
+  if flip-mark {
+    style.mark.end = reverse-arrow-mark(style.mark.end)
+  }
+
+  let pts
+  let comment-pt
+  let comment-anchor
+  let comment-angle = 0deg
+
+  if seq.p1 == seq.p2 {
+    if seq.flip {
+      x1 = start-info.lx
+    } else {
+      x2 = end-info.rx
+    }
+
+    let x-mid = if seq.flip {
+      calc.min(x1, x2) - 20
+    } else {
+      calc.max(x1, x2) + 20
+    }
+
+    pts = (
+      (x1, start-info.y),
+      (x-mid, start-info.y),
+      (x-mid, end-info.y),
+      (x2, end-info.y)
+    )
+
+    if comment != none {
+      comment-anchor = (
+        start: if x-mid < x1 {"south-east"} else {"south-west"},
+        end: if x-mid < x1 {"south-west"} else {"south-east"},
+        left: "south-west",
+        right: "south-east",
+        center: "south",
+      ).at(seq.comment-align)
+
+      comment-pt = (
+        start: pts.first(),
+        end: pts.at(1),
+        left: if x-mid < x1 {pts.at(1)} else {pts.first()},
+        right: if x-mid < x1 {pts.first()} else {pts.at(1)},
+        center: (pts.first(), 50%, pts.at(1))
+      ).at(seq.comment-align)
+    }
+
+  } else {
+    pts = (
+      (x1, start-info.y),
+      (x2, end-info.y)
+    )
+
+    if comment != none {
+      let start-pt = pts.first()
+      let end-pt = pts.last()
+      if seq.start-tip != "" {
+        start-pt = (pts.first(), COMMENT-PAD, pts.last())
+      }
+      if seq.end-tip != "" {
+        end-pt = (pts.last(), COMMENT-PAD, pts.first())
+      }
+
+      comment-pt = (
+        start: start-pt,
+        end: end-pt,
+        left: if x2 < x1 {end-pt} else {start-pt},
+        right: if x2 < x1 {start-pt} else {end-pt},
+        center: (start-pt, 50%, end-pt)
+      ).at(seq.comment-align)
+
+      comment-anchor = (
+        start: if x2 < x1 {"south-east"} else {"south-west"},
+        end: if x2 < x1 {"south-west"} else {"south-east"},
+        left: "south-west",
+        right: "south-east",
+        center: "south",
+      ).at(seq.comment-align)
+    }
+
+    let (p1, p2) = pts
+    if x2 < x1 {
+      (p1, p2) = (p2, p1)
+    }
+    comment-angle = vector.angle2(p1, p2)
+  }
+
+  // Start circle tip
+  if is-circle-tip(seq.start-tip) {
+    draw.circle(
+      pts.first(),
+      radius: CIRCLE-TIP-RADIUS,
+      stroke: none,
+      fill: seq.color,
+      name: "_circle-start-tip"
+    )
+    pts.at(0) = "_circle-start-tip"
+  
+  // Start cross tip
+  } else if is-cross-tip(seq.start-tip) {
+    let size = CROSS-TIP-SIZE
+    let cross-pt = (
+      pts.first(),
+      size * 2,
+      pts.at(1)
+    )
+    draw.line(
+      (rel: (-size, -size), to: cross-pt),
+      (rel: (size, size), to: cross-pt),
+      stroke: seq.color + 1.5pt
+    )
+    draw.line(
+      (rel: (-size, size), to: cross-pt),
+      (rel: (size, -size), to: cross-pt),
+      stroke: seq.color + 1.5pt
+    )
+    pts.at(0) = cross-pt
+  }
+
+  // End circle tip
+  if is-circle-tip(seq.end-tip) {
+    draw.circle(
+      pts.last(),
+      radius: 3,
+      stroke: none,
+      fill: seq.color,
+      name: "_circle-end-tip"
+    )
+    pts.at(pts.len() - 1) = "_circle-end-tip"
+  
+  // End cross tip
+  } else if is-cross-tip(seq.end-tip) {
+    let size = CROSS-TIP-SIZE
+    let cross-pt = (
+      pts.last(),
+      size * 2,
+      pts.at(pts.len() - 2)
+    )
+    draw.line(
+      (rel: (-size, -size), to: cross-pt),
+      (rel: (size, size), to: cross-pt),
+      stroke: seq.color + 1.5pt
+    )
+    draw.line(
+      (rel: (-size, size), to: cross-pt),
+      (rel: (size, -size), to: cross-pt),
+      stroke: seq.color + 1.5pt
+    )
+    pts.at(pts.len() - 1) = cross-pt
+  }
+
+  draw.line(..pts, ..style)
+
+  if comment != none {
+    draw.content(
+      comment-pt,
+      comment,
+      anchor: comment-anchor,
+      angle: comment-angle,
+      padding: 3pt
+    )
+  }
+
+  if seq.create-dst {
+    let dst-line = ctx.lifelines.at(i2)
+    dst-line.lines.push(("create", end-info.y))
+    ctx.lifelines.at(i2) = dst-line
+  }
+  if seq.enable-dst {
+    let dst-line = ctx.lifelines.at(i2)
+    dst-line.lines.push(("enable", end-info.y, seq.lifeline-style))
+    ctx.lifelines.at(i2) = dst-line
+  }
+
+  if "linked-note" in seq {
+    let m = note.get-size(seq.linked-note)
+    end-info.y = calc.min(end-info.y, y0 - m.height / 2)
+  }
+
+  set-ctx(c => {
+    c.y = end-info.y
+    c.lifelines = ctx.lifelines
+    return c
+  })
+})

src/core/draw/sync.typ

@@ -0,0 +1,32 @@
+#import "/src/core/utils.typ": get-ctx, is-elmt, set-ctx
+
+#let render(sync) = get-ctx(ctx => {
+  set-ctx(c => {
+    c.sync-ys = ()
+    return c
+  })
+
+  for e in sync.elmts {
+    assert(is-elmt(e), message: "Sync element can only contain chronos elements, found " + repr(e))
+    assert(
+      e.type == "seq",
+      message: "Sync element can only contain sequences, found '" + e.type + "'"
+    )
+
+    set-ctx(c => {
+      c.y = ctx.y
+      return c
+    })
+    (e.draw)(e)
+    set-ctx(c => {
+      c.sync-ys.push(c.y)
+      return c
+    })
+  }
+
+  set-ctx(c => {
+    c.y = calc.min(..c.sync-ys)
+    c.remove("sync-ys")
+    return c
+  })
+})

src/core/renderer.typ

@@ -0,0 +1,402 @@
+#import "/src/cetz.typ": canvas, draw
+
+#import "draw/note.typ": get-box as get-note-box, get-size as get-note-size
+#import "draw/participant.typ"
+#import "utils.typ": *
+#import "/src/consts.typ": *
+
+#let DEBUG-INVISIBLE = false
+
+#let init-lifelines(participants) = {
+  return participants.map(p => {
+    p.insert("lifeline-lvl", 0)
+    p.insert("max-lifelines", 0)
+    p
+  })
+}
+
+#let unwrap-syncs(elements) = {
+  let i = 0
+  while i < elements.len() {
+    let elmt = elements.at(i)
+    if elmt.type == "sync" {
+      elements = (
+        elements.slice(0, i + 1) +
+        elmt.elmts +
+        elements.slice(i + 1)
+      )
+    }
+    i += 1
+  }
+  return elements
+}
+
+#let seq-update-lifelines(participants, pars-i, seq) = {
+  let participants = participants
+  let com = if seq.comment == none {""} else {seq.comment}
+  let i1 = pars-i.at(seq.p1)
+  let i2 = pars-i.at(seq.p2)
+  let cell = (
+    elmt: seq,
+    i1: calc.min(i1, i2),
+    i2: calc.max(i1, i2),
+    cell: box(com, inset: 3pt)
+  )
+
+  if seq.disable-src or seq.destroy-src {
+    let p = participants.at(i1)
+    p.lifeline-lvl -= 1
+    participants.at(i1) = p
+  }
+  if seq.disable-dst {
+    let p = participants.at(i2)
+    p.lifeline-lvl -= 1
+    participants.at(i2) = p
+  }
+  if seq.enable-dst {
+    let p = participants.at(i2)
+    p.lifeline-lvl += 1
+    p.max-lifelines = calc.max(p.max-lifelines, p.lifeline-lvl)
+    participants.at(i2) = p
+  }
+
+  return (participants, cell)
+}
+
+#let evt-update-lifelines(participants, pars-i, evt) = {
+  let par-name = evt.participant
+  let i = pars-i.at(par-name)
+  let par = participants.at(i)
+  if evt.event == "disable" or evt.event == "destroy" {
+    par.lifeline-lvl -= 1
+  
+  } else if evt.event == "enable" {
+    par.lifeline-lvl += 1
+    par.max-lifelines = calc.max(par.max-lifelines, par.lifeline-lvl)
+  }
+  participants.at(i) = par
+  return participants
+}
+
+#let note-get-cell(pars-i, note) = {
+  let (p1, p2) = (none, none)
+  let cell = none
+  if note.side == "left" {
+    p1 = "["
+    p2 = note.pos
+    cell = get-note-box(note)
+  } else if note.side == "right" {
+    p1 = note.pos
+    p2 = "]"
+    cell = get-note-box(note)
+  } else if note.side == "over" and note.aligned-with != none {
+    let box1 = get-note-box(note)
+    let box2 = get-note-box(note.aligned-with)
+    let m1 = measure(box1)
+    let m2 = measure(box2)
+    cell = box(
+      width: (m1.width + m2.width) / 2,
+      height: calc.max(m1.height, m2.height)
+    )
+    p1 = note.pos
+    p2 = note.aligned-with.pos
+  } else {
+    return none
+  }
+
+  let i1 = pars-i.at(p1)
+  let i2 = pars-i.at(p2)
+  cell = (
+    elmt: note,
+    i1: calc.min(i1, i2),
+    i2: calc.max(i1, i2),
+    cell: cell
+  )
+
+  return cell
+}
+
+#let compute-max-lifeline-levels(participants, elements, pars-i) = {
+  let cells = ()
+  for elmt in elements {
+    if elmt.type == "seq" {
+      let cell
+      (participants, cell) = seq-update-lifelines(
+        participants,
+        pars-i,
+        elmt
+      )
+      cells.push(cell)
+    } else if elmt.type == "evt" {
+      participants = evt-update-lifelines(
+        participants,
+        pars-i,
+        elmt
+      )
+    
+    } else if elmt.type == "note" {
+      let cell = note-get-cell(pars-i, elmt)
+      if cell != none {
+        cells.push(cell)
+      }
+    }
+  }
+
+  return (participants, elements, cells)
+}
+
+/// Compute minimum widths for participant names and shapes
+#let participants-min-col-widths(participants) = {
+  let widths = ()
+  for i in range(participants.len() - 1) {
+    let p1 = participants.at(i)
+    let p2 = participants.at(i + 1)
+    let m1 = participant.get-size(p1)
+    let m2 = participant.get-size(p2)
+    let w1 = m1.width
+    let w2 = m2.width
+    widths.push(w1 / 2pt + w2 / 2pt + PAR-SPACE)
+  }
+  return widths
+}
+
+/// Compute minimum width for over notes
+#let notes-min-col-widths(elements, widths, pars-i) = {
+  let widths = widths
+  let notes = elements.filter(e => e.type == "note")
+  for n in notes.filter(e => (e.side == "over" and 
+                              type(e.pos) == str)) {
+    
+    let m = get-note-size(n)
+    let i = pars-i.at(n.pos)
+
+    if i < widths.len() {
+      widths.at(i) = calc.max(
+        widths.at(i),
+        m.width / 2 + NOTE-GAP
+      )
+    }
+    if i > 0 {
+      widths.at(i - 1) = calc.max(
+        widths.at(i - 1),
+        m.width / 2 + NOTE-GAP
+      )
+    }
+  }
+  return widths
+}
+
+/// Compute minimum width for simple sequences (spanning 1 column)
+#let simple-seq-min-col-widths(cells, widths) = {
+  let widths = widths
+  for cell in cells.filter(c => c.i2 - c.i1 == 1) {
+    let m = measure(cell.cell)
+    widths.at(cell.i1) = calc.max(
+      widths.at(cell.i1),
+      m.width / 1pt + COMMENT-PAD
+    )
+  }
+  return widths
+}
+
+/// Compute minimum width for self sequences
+#let self-seq-min-col-widths(cells, widths) = {
+  let widths = widths
+  for cell in cells.filter(c => (c.elmt.type == "seq" and
+                                 c.i1 == c.i2)) {
+    let m = measure(cell.cell)
+    let i = cell.i1
+    if cell.elmt.flip {
+      i -= 1
+    }
+    if 0 <= i and i < widths.len() {
+      widths.at(i) = calc.max(
+        widths.at(i),
+        m.width / 1pt + COMMENT-PAD
+      )
+    }
+  }
+  return widths
+}
+
+/// Compute remaining widths for longer sequences (spanning multiple columns)
+#let long-seq-min-col-widths(cells, widths) = {
+  let widths = widths
+  let multicol-cells = cells.filter(c => c.i2 - c.i1 > 1)
+  multicol-cells = multicol-cells.sorted(key: c => {
+    c.i1 * 1000 + c.i2
+  })
+  for cell in multicol-cells {
+    let m = measure(cell.cell)
+    let width = (
+      m.width / 1pt +
+      COMMENT-PAD -
+      widths.slice(cell.i1, cell.i2 - 1).sum()
+    )
+    widths.at(cell.i2 - 1) = calc.max(
+      widths.at(cell.i2 - 1), width
+    )
+  }
+  return widths
+}
+
+/// Add lifeline widths
+#let col-widths-add-lifelines(participants, widths) = {
+  return widths.enumerate().map(((i, w)) => {
+    let p1 = participants.at(i)
+    let p2 = participants.at(i + 1)
+    w += p1.max-lifelines * LIFELINE-W / 2
+    if p2.max-lifelines != 0 {
+      w += LIFELINE-W / 2
+    }
+    return w
+  })
+}
+
+#let process-col-elements(elements, widths, pars-i) = {
+  let widths = widths
+  let cols = elements.filter(e => e.type == "col")
+  for col in cols {
+    let i1 = pars-i.at(col.p1)
+    let i2 = pars-i.at(col.p2)
+    if calc.abs(i1 - i2) != 1 {
+      let i-min = calc.min(i1, i2)
+      let i-max = calc.max(i1, i2)
+      let others = pars-i.pairs()
+                         .sorted(key: p => p.last())
+                         .slice(i-min + 1, i-max)
+                         .map(p => "'" + p.first() + "'")
+                         .join(", ")
+      panic(
+        "Column participants must be consecutive (participants (" +
+        others +
+        ") are in between)"
+      )
+    }
+    let i = calc.min(i1, i2)
+
+    let width = widths.at(i)
+
+    if col.width != auto {
+      width = normalize-units(col.width)
+    }
+
+    width = calc.max(
+      width,
+      normalize-units(col.min-width)
+    )
+    if col.max-width != none {
+      width = calc.min(
+        width,
+        normalize-units(col.max-width)
+      )
+    }
+    widths.at(i) = width + normalize-units(col.margin)
+  }
+  return widths
+}
+
+#let compute-columns-width(participants, elements, pars-i) = {
+  elements = elements.filter(is-elmt)
+  elements = unwrap-syncs(elements)
+
+  let cells
+  (participants, elements, cells) = compute-max-lifeline-levels(participants, elements, pars-i)
+
+  let widths = participants-min-col-widths(participants)
+  widths = notes-min-col-widths(elements, widths, pars-i)
+  widths = simple-seq-min-col-widths(cells, widths)
+  widths = self-seq-min-col-widths(cells, widths)
+  widths = long-seq-min-col-widths(cells, widths)
+  widths = col-widths-add-lifelines(participants, widths)
+  widths = process-col-elements(elements, widths, pars-i)
+  return widths
+}
+
+#let setup-ctx(participants, elements) = (ctx => {
+  let state = ctx.at("shared-state", default: (:))
+
+  let chronos-ctx = (
+    participants: init-lifelines(participants),
+    pars-i: get-participants-i(participants),
+    y: 0,
+    groups: (),
+    lifelines: participants.map(_ => (
+      level: 0,
+      lines: ()
+    ))
+  )
+  chronos-ctx.insert(
+    "widths",
+    compute-columns-width(
+      chronos-ctx.participants,
+      elements,
+      chronos-ctx.pars-i
+    )
+  )
+
+  // Compute each column's X position
+  let x-pos = (0,)
+  for width in chronos-ctx.widths {
+    x-pos.push(x-pos.last() + width)
+  }
+  chronos-ctx.insert("x-pos", x-pos)
+  state.insert("chronos", chronos-ctx)
+  ctx.shared-state = state
+  return (
+    ctx: ctx
+  )
+},)
+
+#let render-debug() = get-ctx(ctx => {
+  for p in ctx.participants.filter(p => p.invisible) {
+    let color = if p.name.starts-with("?") {green} else if p.name.ends-with("?") {red} else {blue}
+    let x = ctx.x-pos.at(p.i)
+    draw.line(
+      (x, 0),
+      (x, ctx.y),
+      stroke: (paint: color, dash: "dotted")
+    )
+    draw.content(
+      (x, 0),
+      p.display-name,
+      anchor: "west",
+      angle: 90deg
+    )
+  }
+})
+
+#let render(participants, elements) = context canvas(length: 1pt, {
+  setup-ctx(participants, elements)
+  
+  // Draw participants (start)
+  get-ctx(ctx => {
+    for p in ctx.participants {
+      if p.from-start and not p.invisible and p.show-top {
+        (p.draw)(p)
+      }
+    }
+  })
+
+  // Draw elements
+  for elmt in elements {
+    if not is-elmt(elmt) {
+      (elmt,)
+    } else if "draw" in elmt and elmt.type != "par" {
+      (elmt.draw)(elmt)
+    }
+  }
+
+  set-ctx(ctx => {
+    ctx.y -= Y-SPACE
+    return ctx
+  })
+
+  draw.on-layer(-1, {
+    if DEBUG-INVISIBLE {
+      render-debug()
+    }
+    
+    participant.render-lifelines()
+  })
+})

src/core/setup.typ

@@ -0,0 +1,320 @@
+#import "draw/group.typ": render-end as grp-render-end
+#import "utils.typ": get-group-span, is-elmt
+#import "/src/participant.typ": _exists as par-exists, _par
+#import "/src/sequence.typ": _seq
+
+#let flatten-group(elmts, i) = {
+  let group = elmts.at(i)
+  elmts.at(i) = group
+  return (
+    elmts.slice(0, i + 1) +
+    group.elmts +
+    ((
+      type: "grp-end",
+      draw: grp-render-end,
+      start-i: i
+    ),) +
+    elmts.slice(i+1)
+  )
+}
+
+#let update-group-children(elmts, i) = {
+  let elmts = elmts
+  let group-end = elmts.at(i)
+  
+  elmts.at(group-end.start-i).elmts = elmts.slice(group-end.start-i + 1, i)
+  return elmts
+}
+
+#let convert-return(elmts, i, activation-history) = {
+  if activation-history.len() == 0 {
+    panic("Cannot return if no lifeline is activated")
+  }
+  let elmts = elmts
+  let activation-history = activation-history
+  let ret = elmts.at(i)
+  let seq = activation-history.pop()
+  elmts.at(i) = _seq(
+    seq.p2, seq.p1,
+    comment: ret.comment,
+    disable-src: true,
+    dashed: true
+  ).first()
+  return (elmts, activation-history)
+}
+
+#let unwrap-containers(elmts) = {
+  let elmts = elmts
+  let i = 0
+  let activation-history = ()
+
+  // Flatten groups + convert returns
+  while i < elmts.len() {
+    let elmt = elmts.at(i)
+    if not is-elmt(elmt) {
+      i += 1
+      continue
+    }
+
+    if elmt.type == "grp" {
+      elmts = flatten-group(elmts, i)
+
+    } else if elmt.type == "seq" {
+      if elmt.enable-dst {
+        activation-history.push(elmt)
+      }
+    
+    } else if elmt.type == "evt" {
+      if elmt.event == "enable" {
+        for elmt2 in elmts.slice(0, i).rev() {
+          if elmt2.type == "seq" {
+            activation-history.push(elmt2)
+            break
+          }
+        }
+      }
+    
+    } else if elmt.type == "ret" {
+      (elmts, activation-history) = convert-return(elmts, i, activation-history)
+    }
+    i += 1
+  }
+
+  return (elmts, activation-history)
+}
+
+
+#let prepare-seq-participants(ctx, seq) = {
+  let ctx = ctx
+  if not par-exists(ctx.participants, seq.p1) {
+    ctx.participants.push(_par(seq.p1).first())
+  }
+  if not par-exists(ctx.participants, seq.p2) {
+    ctx.participants.push(_par(
+      seq.p2,
+      from-start: not seq.create-dst
+    ).first())
+  
+  } else if seq.create-dst {
+    let i = ctx.participants.position(p => p.name == seq.p2)
+    ctx.participants.at(i).from-start = false
+  }
+
+  let p1 = seq.p1
+  let p2 = seq.p2
+  if seq.p1 == "?" {
+    p1 = "?" + seq.p2
+  }
+  if seq.p2 == "?" {
+    p2 = seq.p1 + "?"
+  }
+  ctx.linked.push(p1)
+  ctx.linked.push(p2)
+  ctx.last-seq = (
+    seq: seq,
+    i: ctx.i,
+    p1: p1,
+    p2: p2
+  )
+  return ctx
+}
+
+#let prepare-note-participants(ctx, note) = {
+  let ctx = ctx
+  let note = note
+  note.insert(
+    "linked",
+    note.pos == none and note.side != "across"
+  )
+  if note.pos == none and note.side != "across" {
+    let names = ctx.participants.map(p => p.name)
+    let i1 = names.position(n => n == ctx.last-seq.p1)
+    let i2 = names.position(n => n == ctx.last-seq.p2)
+    let pars = (
+      (i1, ctx.last-seq.p1),
+      (i2, ctx.last-seq.p2)
+    ).sorted(key: p => p.first())
+
+    if note.side == "left" {
+      note.pos = pars.first().last()
+    } else if note.side == "right" {
+      note.pos = pars.last().last()
+    }
+
+    let seq = ctx.last-seq.seq
+    seq.insert("linked-note", note)
+    ctx.elmts.at(ctx.last-seq.i) = seq
+  }
+  if note.aligned {
+    let n = ctx.last-note.note
+    n.aligned-with = note
+    ctx.elmts.at(ctx.last-note.i) = n
+  }
+  if note.side == "left" {
+    ctx.linked.push("[")
+  } else if note.side == "right" {
+    ctx.linked.push("]")
+  }
+
+  let pars = none
+  if type(note.pos) == str {
+    pars = (note.pos,)
+  } else if type(note.pos) == array {
+    pars = note.pos
+  }
+  if pars != none {
+    for par in pars {
+      if not par-exists(ctx.participants, par) {
+        participants.push(_par(par).first())
+      }
+    }
+  }
+
+  ctx.elmts.at(ctx.i) = note
+
+  ctx.last-note = (
+    note: note,
+    i: ctx.i
+  )
+
+  return ctx
+}
+
+#let prepare-evt-participants(ctx, evt) = {
+  let par = evt.participant
+  if not par-exists(ctx.participants, par) {
+    let p = _par(
+      par,
+      from-start: evt.event != "create"
+    ).first()
+    ctx.participants.push(p)
+  
+  } else if evt.event == "create" {
+    let i = ctx.participants.position(p => p.name == par)
+    ctx.participants.at(i).from-start = false
+  }
+  return ctx
+}
+
+#let normalize-special-participants(elmt) = {
+  if elmt.p1 == "?" {
+    elmt.p1 = "?" + elmt.p2
+  } else if elmt.p2 == "?" {
+    elmt.p2 = elmt.p1 + "?"
+  }
+  return elmt
+}
+
+#let prepare-participants(elmts) = {
+  let ctx = (
+    linked: (),
+    last-seq: none,
+    last-note: none,
+    participants: (),
+    elmts: elmts,
+    i: 0
+  )
+
+  for (i, elmt) in ctx.elmts.enumerate() {
+    ctx.i = i
+    if not is-elmt(elmt) {
+      continue
+    }
+
+    if elmt.type == "par" {
+      ctx.participants.push(elmt)
+
+    } else if elmt.type == "seq" {
+      ctx = prepare-seq-participants(ctx, elmt)
+    
+    } else if elmt.type == "note" {
+      ctx = prepare-note-participants(ctx, elmt)
+    
+    } else if elmt.type == "evt" {
+      ctx = prepare-evt-participants(ctx, elmt)
+    }
+  }
+  ctx.linked = ctx.linked.dedup()
+
+  let pars = ctx.participants
+  let participants = ()
+  
+  if "[" in ctx.linked {
+    participants.push(_par("[", invisible: true).first())
+  }
+  
+  for (i, p) in pars.enumerate() {
+    let before = _par(
+      "?" + p.name,
+      invisible: true
+    ).first()
+    let after = _par(
+      p.name + "?",
+      invisible: true
+    ).first()
+    
+    if before.name in ctx.linked {
+      if participants.len() == 0 or not participants.last().name.ends-with("?") {
+        participants.push(before)
+      } else {
+        participants.insert(-1, before)
+      }
+    }
+
+    participants.push(p)
+
+    if after.name in ctx.linked {
+      participants.push(after)
+    }
+  }
+  if "]" in ctx.linked {
+    participants.push(_par(
+      "]",
+      invisible: true
+    ).first())
+  }
+
+  return (ctx.elmts, participants)
+}
+
+#let finalize-setup(elmts, participants) = {
+  for (i, p) in participants.enumerate() {
+    p.insert("i", i)
+    participants.at(i) = p
+  }
+
+  let containers = ()
+
+  for (i, elmt) in elmts.enumerate() {
+    if not is-elmt(elmt) {
+      continue
+    }
+    if elmt.type == "seq" {
+      elmts.at(i) = normalize-special-participants(elmt)
+    } else if elmt.type == "grp-end" {
+      // Put back elements in group because they might have changed
+      elmts = update-group-children(elmts, i)
+    } else if elmt.type in ("grp", "alt") {
+      containers.push(i)
+    }
+  }
+
+  // Compute groups spans (horizontal)
+  for i in containers {
+    let elmt = elmts.at(i)
+    let (min-i, max-i) = get-group-span(participants, elmt)
+    elmts.at(i).insert("min-i", min-i)
+    elmts.at(i).insert("max-i", max-i)
+  }
+
+  return (elmts, participants)
+}
+
+#let setup(elements) = {
+  let (elmts, activation-history) = unwrap-containers(elements)
+  
+  let participants
+  (elmts, participants) = prepare-participants(elmts)
+
+  return finalize-setup(elmts, participants)
+}

src/core/utils.typ

@@ -1,3 +1,15 @@
+#import "/src/cetz.typ": draw
+
+#let is-elmt(elmt) = {
+  if type(elmt) != dictionary {
+    return false
+  }
+  if "type" not in elmt {
+    return false
+  }
+  return true
+}
+
 #let normalize-units(value) = {
   if type(value) == int or type(value) == float {
     return value
@@ -79,4 +91,17 @@
     height: new-h,
     scale(x: r, y: r, reflow: true, canvas)
   )
+})
+
+#let set-ctx(func) = draw.set-ctx(c => {
+  let ctx = c.shared-state.chronos
+  let new-ctx = func(ctx)
+  assert(new-ctx != none, message: "set-ctx must return a context!")
+  c.shared-state.chronos = new-ctx
+  return c
+})
+
+#let get-ctx(func) = draw.get-ctx(c => {
+  let ctx = c.shared-state.chronos
+  func(ctx)
 })

src/diagram.typ

@@ -1,249 +1,14 @@
-#import "utils.typ": get-group-span, fit-canvas
-#import "renderer.typ": render
-#import "participant.typ" as participant: _par, PAR-SPECIALS
-#import "sequence.typ": _seq
-
-#let _gap(size: 20) = {
-  return ((
-    type: "gap",
-    size: size
-  ),)
-}
-
-#let _evt(participant, event) = {
-  return ((
-    type: "evt",
-    participant: participant,
-    event: event,
-    lifeline-style: auto
-  ),)
-}
-
-#let _col(p1, p2, width: auto, margin: 0, min-width: 0, max-width: none) = {
-  return ((
-    type: "col",
-    p1: p1,
-    p2: p2,
-    width: width,
-    margin: margin,
-    min-width: min-width,
-    max-width: max-width
-  ),)
-}
+#import "core/draw/event.typ": render as evt-render
+#import "core/renderer.typ": render
+#import "core/setup.typ": setup
+#import "core/utils.typ": fit-canvas, set-ctx
 
 #let diagram(elements, width: auto) = {
   if elements == none {
     return
   }
   
-  let participants = ()
-  let elmts = elements
-  let i = 0
-
-  let activation-history = ()
-
-  // Flatten groups + convert returns
-  while i < elmts.len() {
-    let elmt = elmts.at(i)
-    if elmt.type == "grp" {
-      elmt.elmts = elmt.elmts.map(e => {
-        if e.type == "seq" {
-          if e.p1 == "?" {
-            e.p1 = "?" + e.p2
-          } else if e.p2 == "?" {
-            e.p2 = e.p1 + "?"
-          }
-        }
-        e
-      })
-      elmts.at(i) = elmt
-      elmts = (
-        elmts.slice(0, i + 1) +
-        elmt.elmts +
-        ((
-          type: "grp-end",
-          start-i: i
-        ),) +
-        elmts.slice(i+1)
-      )
-    } else if elmt.type == "grp-end" {
-      // Put back elements in group because they might have changed
-      elmts.at(elmt.start-i).elmts = elmts.slice(elmt.start-i + 1, i)
-
-    } else if elmt.type == "seq" {
-      if elmt.enable-dst {
-        activation-history.push(elmt)
-      }
-    } else if elmt.type == "evt" {
-      if elmt.event == "enable" {
-        for elmt2 in elmts.slice(0, i).rev() {
-          if elmt2.type == "seq" {
-            activation-history.push(elmt2)
-            break
-          }
-        }
-      }
-    } else if elmt.type == "ret" {
-      if activation-history.len() == 0 {
-        panic("Cannot return if no lifeline is activated")
-      }
-      let seq = activation-history.pop()
-      elmts.at(i) = _seq(
-        seq.p2, seq.p1,
-        comment: elmt.comment,
-        disable-src: true,
-        dashed: true
-      ).first()
-    }
-    i += 1
-  }
-
-  // List participants
-  let linked = ()
-  let last-seq = none
-  let last-note = none
-  for (i, elmt) in elmts.enumerate() {
-    if elmt.type == "par" {
-      participants.push(elmt)
-    } else if elmt.type == "seq" {
-      if not participant._exists(participants, elmt.p1) {
-        participants.push(_par(elmt.p1).first())
-      }
-      if not participant._exists(participants, elmt.p2) {
-        let par = _par(elmt.p2, from-start: not elmt.create-dst).first()
-        participants.push(par)
-      
-      } else if elmt.create-dst {
-        let i = participants.position(p => p.name == elmt.p2)
-        participants.at(i).from-start = false
-      }
-
-      let p1 = elmt.p1
-      let p2 = elmt.p2
-      if elmt.p1 == "?" {
-        p1 = "?" + elmt.p2
-      }
-      if elmt.p2 == "?" {
-        p2 = elmt.p1 + "?"
-      }
-      linked.push(p1)
-      linked.push(p2)
-      last-seq = (
-        elmt: elmt,
-        i: i,
-        p1: p1,
-        p2: p2
-      )
-    } else if elmt.type == "note" {
-      elmt.insert("linked", elmt.pos == none and elmt.side != "across")
-      if elmt.pos == none and elmt.side != "across" {
-        let names = participants.map(p => p.name)
-        let i1 = names.position(n => n == last-seq.p1)
-        let i2 = names.position(n => n == last-seq.p2)
-        let pars = ((i1, last-seq.p1), (i2, last-seq.p2)).sorted(key: p => p.first())
-        if elmt.side == "left" {
-          elmt.pos = pars.first().last()
-        } else if elmt.side == "right" {
-          elmt.pos = pars.last().last()
-        }
-
-        let seq = last-seq.elmt
-        seq.insert("linked-note", elmt)
-        elmts.at(last-seq.i) = seq
-      }
-      if elmt.aligned {
-        let n = last-note.elmt
-        n.aligned-with = elmt
-        elmts.at(last-note.i) = n
-      }
-      elmts.at(i) = elmt
-      if elmt.side == "left" {
-        linked.push("[")
-      } else if elmt.side == "right" {
-        linked.push("]")
-      }
-
-      let pars = none
-      if type(elmt.pos) == str {
-        pars = (elmt.pos,)
-      } else if type(elmt.pos) == array {
-        pars = elmt.pos
-      }
-      if pars != none {
-        for par in pars {
-          if not participant._exists(participants, par) {
-            participants.push(_par(par).first())
-          }
-        }
-      }
-
-      last-note = (
-        elmt: elmt,
-        i: i
-      )
-    } else if elmt.type == "evt" {
-      let par = elmt.participant
-      if not participant._exists(participants, par) {
-        let p = _par(par, from-start: elmt.event != "create").first()
-        participants.push(p)
-      
-      } else if elmt.event == "create" {
-        let i = participants.position(p => p.name == par)
-        participants.at(i).from-start = false
-      }
-    }
-  }
-  linked = linked.dedup()
-
-  let pars = participants
-  participants = ()
-  
-  if "[" in linked {
-    participants.push(_par("[", invisible: true).first())
-  }
-  
-  for (i, p) in pars.enumerate() {
-    let before = _par("?" + p.name, invisible: true).first()
-    let after = _par(p.name + "?", invisible: true).first()
-    
-    if before.name in linked {
-      if participants.len() == 0 or not participants.last().name.ends-with("?") {
-        participants.push(before)
-      } else {
-        participants.insert(-1, before)
-      }
-    }
-
-    participants.push(p)
-
-    if after.name in linked {
-      participants.push(after)
-    }
-  }
-  if "]" in linked {
-    participants.push(_par("]", invisible: true).first())
-  }
-
-  // Add index to participant
-  for (i, p) in participants.enumerate() {
-    p.insert("i", i)
-    participants.at(i) = p
-  }
-
-  // Compute groups spans (horizontal)
-  for (i, elmt) in elmts.enumerate() {
-    if elmt.type == "grp" or elmt.type == "alt" {
-      let (min-i, max-i) = get-group-span(participants, elmt)
-      elmts.at(i).insert("min-i", min-i)
-      elmts.at(i).insert("max-i", max-i)
-    } else if elmt.type == "seq" {
-      if elmt.p1 == "?" {
-        elmts.at(i).p1 = "?" + elmt.p2
-      } else if elmt.p2 == "?" {
-        elmts.at(i).p2 = elmt.p1 + "?"
-      }
-    }
-  }
+  let (elmts, participants) = setup(elements)
 
   let canvas = render(participants, elmts)
   fit-canvas(canvas, width: width)

src/group.typ

@@ -1,9 +1,9 @@
-#import "/src/cetz.typ": draw
-#import "consts.typ": *
+#import "core/draw/group.typ"
 
 #let _grp(name, desc: none, type: "default", elmts) = {
   return ((
     type: "grp",
+    draw: group.render-start,
     name: name,
     desc: desc,
     grp-type: type,
@@ -20,6 +20,7 @@
     let else-elmts = args.at(i + 1, default: ())
     all-elmts.push((
       type: "else",
+      draw: group.render-else,
       desc: else-desc
     ))
     all-elmts += else-elmts
@@ -40,60 +41,3 @@
 }
 #let _opt(desc, elmts) = grp("opt", desc: desc, type: "opt", elmts)
 #let _break(desc, elmts) = grp("break", desc: desc, type: "break", elmts)
-
-#let render(x0, x1, y0, y1, group) = {
-  let shapes = ()
-  let name = text(group.name, weight: "bold")
-  let m = measure(box(name))
-  let w = m.width / 1pt + 15
-  let h = m.height / 1pt + 6
-  shapes += draw.rect(
-    (x0, y0),
-    (x1, y1)
-  )
-  shapes += draw.merge-path(
-    fill: COL-GRP-NAME,
-    close: true,
-    {
-      draw.line(
-        (x0, y0),
-        (x0 + w, y0),
-        (x0 + w, y0 - h / 2),
-        (x0 + w - 5, y0 - h),
-        (x0, y0 - h)
-      )
-    }
-  )
-  shapes += draw.content(
-    (x0, y0),
-    name,
-    anchor: "north-west",
-    padding: (left: 5pt, right: 10pt, top: 3pt, bottom: 3pt)
-  )
-
-  if group.desc != none {
-    shapes += draw.content(
-      (x0 + w, y0),
-      text([\[#group.desc\]], weight: "bold", size: .8em),
-      anchor: "north-west",
-      padding: 3pt
-    )
-  }
-
-  return shapes
-}
-
-#let render-else(x0, x1, y, elmt) = {
-  let shapes = draw.line(
-    (x0, y),
-    (x1, y),
-    stroke: (dash: (2pt, 1pt), thickness: .5pt)
-  )
-  shapes += draw.content(
-    (x0, y),
-    text([\[#elmt.desc\]], weight: "bold", size: .8em),
-    anchor: "north-west",
-    padding: 3pt
-  )
-  return shapes
-}

src/lib.typ

@@ -1,9 +1,8 @@
 #let version = version(0, 2, 2)
-#import "diagram.typ": diagram, from-plantuml, _gap, _evt, _col
+#import "diagram.typ": diagram, from-plantuml
 
 #import "sequence.typ": _seq, _ret
 #import "group.typ": _grp, _loop, _alt, _opt, _break
 #import "participant.typ": _par
-#import "separator.typ": _sep, _delay
-#import "note.typ": _note
-#import "sync.typ": _sync
+#import "misc.typ": _sep, _delay, _sync, _gap, _evt, _col
+#import "note.typ": _note

src/misc.typ

@@ -0,0 +1,64 @@
+#import "core/draw/delay.typ"
+#import "core/draw/separator.typ"
+#import "core/draw/sync.typ"
+#import "core/utils.typ": set-ctx
+
+#let _sep(name) = {
+  return ((
+    type: "sep",
+    draw: separator.render,
+    name: name
+  ),)
+}
+
+#let _delay(name: none, size: 30) = {
+  return ((
+    type: "delay",
+    draw: delay.render,
+    name: name,
+    size: size
+  ),)
+}
+
+#let _sync(elmts) = {
+  return ((
+    type: "sync",
+    draw: sync.render,
+    elmts: elmts
+  ),)
+}
+
+#let gap-render(gap) = set-ctx(ctx => {
+  ctx.y -= gap.size
+  return ctx
+})
+
+#let _gap(size: 20) = {
+  return ((
+    type: "gap",
+    draw: gap-render,
+    size: size
+  ),)
+}
+
+#let _evt(participant, event) = {
+  return ((
+    type: "evt",
+    draw: evt-render,
+    participant: participant,
+    event: event,
+    lifeline-style: auto
+  ),)
+}
+
+#let _col(p1, p2, width: auto, margin: 0, min-width: 0, max-width: none) = {
+  return ((
+    type: "col",
+    p1: p1,
+    p2: p2,
+    width: width,
+    margin: margin,
+    min-width: min-width,
+    max-width: max-width
+  ),)
+}

src/note.typ

@@ -1,5 +1,5 @@
-#import "/src/cetz.typ": draw
 #import "consts.typ": *
+#import "core/draw/note.typ"
 
 #let SIDES = (
   "left",
@@ -30,6 +30,7 @@
   }
   return ((
     type: "note",
+    draw: note.render,
     side: side,
     content: content,
     pos: pos,
@@ -39,147 +40,3 @@
     aligned-with: none
   ),)
 }
-
-#let get-note-box(note) = {
-  let PAD = if note.shape == "hex" {NOTE-HEX-PAD} else {NOTE-PAD}
-  let inset = (
-    left: PAD.last() * 1pt,
-    right: PAD.last() * 1pt,
-    top: PAD.first() * 1pt,
-    bottom: PAD.first() * 1pt,
-  )
-  if note.shape == "default" {
-    inset.right += NOTE-CORNER-SIZE * 1pt
-  }
-  if note.side == "left" {
-    inset.right += NOTE-GAP * 1pt
-  } else if note.side == "right" {
-    inset.left += NOTE-GAP * 1pt
-  }
-  return box(note.content, inset: inset)
-}
-
-#let get-size(note) = {
-  let PAD = if note.shape == "hex" {NOTE-HEX-PAD} else {NOTE-PAD}
-  let m = measure(box(note.content))
-  let w = m.width / 1pt + PAD.last() * 2
-  let h = m.height / 1pt + PAD.first() * 2
-  if note.shape == "default" {
-    w += NOTE-CORNER-SIZE
-  }
-  return (
-    width: w,
-    height: h
-  )
-}
-
-#let _get-base-x(pars-i, x-pos, note) = {
-  if note.side == "across" {
-    return (x-pos.first() + x-pos.last()) / 2
-  }
-  if note.side == "over" {
-    if type(note.pos) == array {
-      let xs = note.pos.map(par => x-pos.at(pars-i.at(par)))
-      return (calc.min(..xs) + calc.max(..xs)) / 2
-    }
-  }
-  return x-pos.at(pars-i.at(note.pos))
-}
-
-#let render(pars-i, x-pos, note, y, lifelines) = {
-  let shapes = ()
-  let PAD = if note.shape == "hex" {NOTE-HEX-PAD} else {NOTE-PAD}
-  let m = measure(box(note.content))
-  let w = m.width / 1pt + PAD.last() * 2
-  let h = m.height / 1pt + PAD.first() * 2
-  let total-w = w
-  if note.shape == "default" {
-    total-w += NOTE-CORNER-SIZE
-  }
-
-  let base-x = _get-base-x(pars-i, x-pos, note)
-
-  let i = none
-  if note.pos != none and type(note.pos) == str {
-    i = pars-i.at(note.pos)
-  }
-  let x0 = base-x
-  if note.side == "left" {
-    x0 -= NOTE-GAP
-    x0 -= total-w
-    if lifelines.at(i).level != 0 {
-      x0 -= LIFELINE-W / 2
-    }
-  } else if note.side == "right" {
-    x0 += NOTE-GAP
-    x0 += lifelines.at(i).level * LIFELINE-W / 2
-  } else if note.side == "over" or note.side == "across" {
-    x0 -= total-w / 2
-  }
-
-  let x1 = x0 + w
-  let x2 = x0 + total-w
-  let y0 = y
-
-  if note.linked {
-    y0 += h / 2
-  }
-  let y1 = y0 - h
-
-  if note.shape == "default" {
-    shapes += draw.merge-path(
-      stroke: black + .5pt,
-      fill: note.color,
-      close: true,
-      {
-        draw.line(
-          (x0, y0),
-          (x1, y0),
-          (x2, y0 - NOTE-CORNER-SIZE),
-          (x2, y1),
-          (x0, y1)
-        )
-      }
-    )
-    shapes += draw.line((x1, y0), (x1, y0 - NOTE-CORNER-SIZE), (x2, y0 - NOTE-CORNER-SIZE), stroke: black + .5pt)
-  } else if note.shape == "rect" {
-    shapes += draw.rect(
-      (x0, y0),
-      (x2, y1),
-      stroke: black + .5pt,
-      fill: note.color
-    )
-  } else if note.shape == "hex" {
-    let lx = x0 + PAD.last()
-    let rx = x2 - PAD.last()
-    let my = (y0 + y1) / 2
-    shapes += draw.merge-path(
-      stroke: black + .5pt,
-      fill: note.color,
-      close: true,
-      {
-        draw.line(
-          (lx, y0),
-          (rx, y0),
-          (x2, my),
-          (rx, y1),
-          (lx, y1),
-          (x0, my),
-        )
-      }
-    )
-  }
-
-  shapes += draw.content(
-    ((x0 + x1)/2, (y0 + y1)/2),
-    note.content,
-    anchor: "center"
-  )
-
-  if note.aligned-with == none and (note.pos != none or note.side == "across") {
-    y -= h
-  }
-
-  let r = (y, shapes)
-  return r
-}

src/participant.typ

@@ -1,7 +1,6 @@
-#import "/src/cetz.typ": draw
-#import "consts.typ": *
+#import "core/draw/participant.typ"
 
-#let PAR-SPECIALS = "?[]"
+#let PAR-SPECIALS = ("?", "[", "]")
 #let SHAPES = (
   "participant",
   "actor",
@@ -36,6 +35,7 @@
   }
   return ((
     type: "par",
+    draw: participant.render,
     name: name,
     display-name: if display-name == auto {name} else {display-name},
     from-start: from-start,
@@ -50,7 +50,7 @@
 }
 
 #let _exists(participants, name) = {
-  if name == "?" or name == "[" or name == "]" {
+  if name in PAR-SPECIALS {
     return true
   }
 
@@ -61,307 +61,3 @@
   }
   return false
 }
-
-#let get-size(par) = {
-  if par.invisible {
-    return (width: 0pt, height: 0pt)
-  }
-  let m = measure(box(par.display-name))
-  let w = m.width
-  let h = m.height
-  let (shape-w, shape-h) = (
-    participant: (w + PAR-PAD.last() * 2, h + PAR-PAD.first() * 2),
-    actor: (ACTOR-WIDTH * 1pt, ACTOR-WIDTH * 2pt + SYM-GAP * 1pt + h),
-    boundary: (BOUNDARY-HEIGHT * 2pt, BOUNDARY-HEIGHT * 1pt + SYM-GAP * 1pt + h),
-    control: (CONTROL-HEIGHT * 1pt, CONTROL-HEIGHT * 1pt + SYM-GAP * 1pt + h),
-    entity: (ENTITY-HEIGHT * 1pt, ENTITY-HEIGHT * 1pt + 2pt + SYM-GAP * 1pt + h),
-    database: (DATABASE-WIDTH * 1pt, DATABASE-WIDTH * 4pt / 3 + SYM-GAP * 1pt + h),
-    collections: (
-      w + COLLECTIONS-PAD.last() * 2 + calc.abs(COLLECTIONS-DX) * 1pt,
-      h + COLLECTIONS-PAD.first() * 2 + calc.abs(COLLECTIONS-DY) * 1pt,
-    ),
-    queue: (
-      w + QUEUE-PAD.last() * 2 + 3 * (h + QUEUE-PAD.first() * 2) / 4,
-      h + QUEUE-PAD.first() * 2
-    ),
-    custom: (
-      measure(par.custom-image).width,
-      measure(par.custom-image).height + SYM-GAP * 1pt + h
-    )
-  ).at(par.shape)
-
-  return (
-    width: calc.max(w, shape-w),
-    height: calc.max(h, shape-h)
-  )
-}
-
-#let _render-participant(x, y, p, m, bottom) = {
-  let w = m.width / 1pt
-  let h = m.height / 1pt
-  let x0 = x - w / 2 - PAR-PAD.last() / 1pt
-  let x1 = x + w / 2 + PAR-PAD.last() / 1pt
-  let y0 = y + h + PAR-PAD.first() / 1pt * 2
-  if bottom {
-    y0 = y
-  }
-  let y1 = y0 - h - PAR-PAD.first() / 1pt * 2
-
-  draw.rect(
-    (x0, y0),
-    (x1, y1),
-    radius: 2pt,
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  draw.content(
-    ((x0 + x1) / 2, (y0 + y1) / 2),
-    p.display-name,
-    anchor: "center"
-  )
-}
-
-#let _render-actor(x, y, p, m, bottom) = {
-  let w2 = ACTOR-WIDTH / 2
-  let head-r = ACTOR-WIDTH / 4
-  let height = ACTOR-WIDTH * 2
-  let arms-y = height * 0.375
-
-  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + height + SYM-GAP}
-  draw.circle(
-    (x, y0 - head-r),
-    radius: head-r,
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  draw.line((x, y0 - head-r * 2), (x, y0 - height + w2), stroke: black + .5pt)
-  draw.line((x - w2, y0 - arms-y), (x + w2, y0 - arms-y), stroke: black + .5pt)
-  draw.line((x - w2, y0 - height), (x, y0 - height + w2), (x + w2, y0 - height), stroke: black + .5pt)
-  draw.content(
-    (x, y),
-    p.display-name,
-    anchor: if bottom {"north"} else {"south"}
-  )
-}
-
-#let _render-boundary(x, y, p, m, bottom) = {
-  let circle-r = BOUNDARY-HEIGHT / 2
-  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + BOUNDARY-HEIGHT + SYM-GAP}
-  let x0 = x - BOUNDARY-HEIGHT
-  let y1 = y0 - circle-r
-  let y2 = y0 - BOUNDARY-HEIGHT
-
-  draw.circle(
-    (x + circle-r, y1),
-    radius: circle-r,
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  draw.line(
-    (x0, y0), (x0, y2),
-    stroke: black + .5pt
-  )
-  draw.line(
-    (x0, y1), (x, y1),
-    stroke: black + .5pt
-  )
-  draw.content(
-    (x, y),
-    p.display-name,
-    anchor: if bottom {"north"} else {"south"}
-  )
-}
-
-#let _render-control(x, y, p, m, bottom) = {
-  let r = CONTROL-HEIGHT / 2
-  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + CONTROL-HEIGHT + SYM-GAP}
-
-  draw.circle(
-    (x, y0 - r),
-    radius: r,
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  draw.mark((x, y0), (x - r / 2, y0), symbol: "stealth", fill: black)
-  draw.content(
-    (x, y),
-    p.display-name,
-    anchor: if bottom {"north"} else {"south"}
-  )
-}
-
-#let _render-entity(x, y, p, m, bottom) = {
-  let r = ENTITY-HEIGHT / 2
-  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + ENTITY-HEIGHT + SYM-GAP}
-  let y1 = y0 - ENTITY-HEIGHT - 1.5
-
-  draw.circle(
-    (x, y0 - r),
-    radius: r,
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  draw.line(
-    (x - r, y1),
-    (x + r, y1),
-    stroke: black + .5pt
-  )
-  draw.content(
-    (x, y),
-    p.display-name,
-    anchor: if bottom {"north"} else {"south"}
-  )
-}
-
-#let _render-database(x, y, p, m, bottom) = {
-  let height = DATABASE-WIDTH * 4 / 3
-  let rx = DATABASE-WIDTH / 2
-  let ry = rx / 2
-  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + height + SYM-GAP}
-  let y1 = y0 - height
-
-  draw.merge-path(
-    close: true,
-    fill: p.color,
-    stroke: black + .5pt,
-    {
-      draw.bezier((x - rx, y0 - ry), (x, y0), (x - rx, y0 - ry/2), (x - rx/2, y0))
-      draw.bezier((), (x + rx, y0 - ry), (x + rx/2, y0), (x + rx, y0 - ry/2))
-      draw.line((), (x + rx, y1 + ry))
-      draw.bezier((), (x, y1), (x + rx, y1 + ry/2), (x + rx/2, y1))
-      draw.bezier((), (x - rx, y1 + ry), (x - rx/2, y1), (x - rx, y1 + ry/2))
-    }
-  )
-  draw.merge-path(
-    stroke: black + .5pt,
-    {
-      draw.bezier((x - rx, y0 - ry), (x, y0 - ry*2), (x - rx, y0 - 3*ry/2), (x - rx/2, y0 - ry*2))
-      draw.bezier((), (x + rx, y0 - ry), (x + rx/2, y0 - ry*2), (x + rx, y0 - 3*ry/2))
-    }
-  )
-  draw.content(
-    (x, y),
-    p.display-name,
-    anchor: if bottom {"north"} else {"south"}
-  )
-}
-
-#let _render-collections(x, y, p, m, bottom) = {
-  let w = m.width / 1pt
-  let h = m.height / 1pt
-  let dx = COLLECTIONS-DX
-  let dy = COLLECTIONS-DY
-  let total-w = w + PAR-PAD.last() * 2 / 1pt + calc.abs(dx)
-  let total-h = h + PAR-PAD.first() * 2 / 1pt + calc.abs(dy)
-
-  let x0 = x - total-w / 2
-  let x1 = x0 + calc.abs(dx)
-  let x3 = x0 + total-w
-  let x2 = x3 - calc.abs(dx)
-  
-  let y0 = if bottom {y} else {y + total-h}
-  let y1 = y0 - calc.abs(dy)
-  let y3 = y0 - total-h
-  let y2 = y3 + calc.abs(dy)
-
-  let r1 = (x1, y0, x3, y2)
-  let r2 = (x0, y1, x2, y3)
-
-  if dx < 0 {
-    r1.at(0) = x0
-    r1.at(2) = x2
-    r2.at(0) = x1
-    r2.at(2) = x3
-  }
-
-  if dy < 0 {
-    r1.at(1) = y1
-    r1.at(3) = y3
-    r2.at(1) = y0
-    r2.at(3) = y2
-  }
-  draw.rect(
-    (r1.at(0), r1.at(1)),
-    (r1.at(2), r1.at(3)),
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  draw.rect(
-    (r2.at(0), r2.at(1)),
-    (r2.at(2), r2.at(3)),
-    fill: p.color,
-    stroke: black + .5pt
-  )
-  
-  draw.content(
-    ((r2.at(0) + r2.at(2)) / 2, (r2.at(1) + r2.at(3)) / 2),
-    p.display-name,
-    anchor: "center"
-  )
-}
-
-#let _render-queue(x, y, p, m, bottom) = {
-  let w = (m.width + QUEUE-PAD.last() * 2) / 1pt
-  let h = (m.height + QUEUE-PAD.first() * 2) / 1pt
-  let total-h = h
-  let ry = total-h / 2
-  let rx = ry / 2
-  let total-w = w + 3 + 3 * rx
-
-  let x0 = x - total-w / 2
-  let y0 = if bottom {y} else {y + total-h}
-  let y1 = y0 - total-h
-  let x-left = x0 + rx
-  let x-right = x-left + w + rx
-  draw.merge-path(
-    close: true,
-    fill: p.color,
-    stroke: black + .5pt,
-    {
-      draw.bezier((x-right, y0), (x-right + rx, y0 - ry), (x-right + rx/2, y0), (x-right + rx, y0 - ry/2))
-      draw.bezier((), (x-right, y1), (x-right + rx, y1 + ry/2), (x-right + rx/2, y1))
-      draw.line((), (x-left, y1))
-      draw.bezier((), (x-left - rx, y0 - ry), (x-left - rx/2, y1), (x-left - rx, y1 + ry/2))
-      draw.bezier((), (x-left, y0), (x-left - rx, y0 - ry/2), (x-left - rx/2, y0))
-    }
-  )
-  draw.merge-path(
-    stroke: black + .5pt,
-    {
-      draw.bezier((x-right, y0), (x-right - rx, y0 - ry), (x-right - rx/2, y0), (x-right - rx, y0 - ry/2))
-      draw.bezier((), (x-right, y1), (x-right - rx, y1 + ry/2), (x-right - rx/2, y1))
-    }
-  )
-  draw.content(
-    ((x-left + x-right - rx) / 2, y0 - ry),
-    p.display-name,
-    anchor: "center"
-  )
-}
-
-#let _render-custom(x, y, p, m, bottom) = {
-  let image-m = measure(p.custom-image)
-  let y0 = if bottom {y - m.height / 1pt - SYM-GAP} else {y + m.height / 1pt + image-m.height / 1pt + SYM-GAP}
-  draw.content((x - image-m.width / 2pt, y0), p.custom-image, anchor: "north-west")
-  draw.content(
-    (x, y),
-    p.display-name,
-    anchor: if bottom {"north"} else {"south"}
-  )
-}
-
-#let render(x-pos, p, y: 0, bottom: false) = {
-  let m = measure(box(p.display-name))
-  let func = (
-    participant: _render-participant,
-    actor: _render-actor,
-    boundary: _render-boundary,
-    control: _render-control,
-    entity: _render-entity,
-    database: _render-database,
-    collections: _render-collections,
-    queue: _render-queue,
-    custom: _render-custom,
-  ).at(p.shape)
-  func(x-pos.at(p.i), y, p, m, bottom)
-}

src/renderer.typ

@@ -1,510 +0,0 @@
-#import "/src/cetz.typ": canvas, draw
-#import "utils.typ": get-participants-i, get-style, normalize-units
-#import "group.typ"
-#import "participant.typ"
-#import participant: PAR-SPECIALS
-#import "sequence.typ"
-#import "separator.typ"
-#import "sync.typ"
-#import "consts.typ": *
-#import "note.typ" as note: get-note-box
-
-#let DEBUG-INVISIBLE = false
-
-#let get-columns-width(participants, elements) = {
-  participants = participants.map(p => {
-    p.insert("lifeline-lvl", 0)
-    p.insert("max-lifelines", 0)
-    p
-  })
-  let pars-i = get-participants-i(participants)
-  let cells = ()
-
-  // Unwrap syncs
-  let i = 0
-  while i < elements.len() {
-    let elmt = elements.at(i)
-    if elmt.type == "sync" {
-      elements = elements.slice(0, i + 1) + elmt.elmts + elements.slice(i + 1)
-    }
-    i += 1
-  }
-
-  // Compute max lifeline levels
-  for elmt in elements {
-    if elmt.type == "seq" {
-      let com = if elmt.comment == none {""} else {elmt.comment}
-      let i1 = pars-i.at(elmt.p1)
-      let i2 = pars-i.at(elmt.p2)
-      cells.push(
-        (
-          elmt: elmt,
-          i1: calc.min(i1, i2),
-          i2: calc.max(i1, i2),
-          cell: box(com, inset: 3pt)
-        )
-      )
-
-      if elmt.disable-src or elmt.destroy-src {
-        let p = participants.at(i1)
-        p.lifeline-lvl -= 1
-        participants.at(i1) = p
-      }
-      if elmt.disable-dst {
-        let p = participants.at(i2)
-        p.lifeline-lvl -= 1
-        participants.at(i2) = p
-      }
-      if elmt.enable-dst {
-        let p = participants.at(i2)
-        p.lifeline-lvl += 1
-        p.max-lifelines = calc.max(p.max-lifelines, p.lifeline-lvl)
-        participants.at(i2) = p
-      }
-    } else if elmt.type == "evt" {
-      let par-name = elmt.participant
-      let i = pars-i.at(par-name)
-      let par = participants.at(i)
-      if elmt.event == "disable" or elmt.event == "destroy" {
-        par.lifeline-lvl -= 1
-      
-      } else if elmt.event == "enable" {
-        par.lifeline-lvl += 1
-        par.max-lifelines = calc.max(par.max-lifelines, par.lifeline-lvl)
-      }
-      participants.at(i) = par
-    
-    } else if elmt.type == "note" {
-      let (p1, p2) = (none, none)
-      let cell = none
-      if elmt.side == "left" {
-        p1 = "["
-        p2 = elmt.pos
-        cell = get-note-box(elmt)
-      } else if elmt.side == "right" {
-        p1 = elmt.pos
-        p2 = "]"
-        cell = get-note-box(elmt)
-      } else if elmt.side == "over" {
-        if elmt.aligned-with != none {
-          let box1 = get-note-box(elmt)
-          let box2 = get-note-box(elmt.aligned-with)
-          let m1 = measure(box1)
-          let m2 = measure(box2)
-          cell = box(width: (m1.width + m2.width) / 2, height: calc.max(m1.height, m2.height))
-          p1 = elmt.pos
-          p2 = elmt.aligned-with.pos
-        }
-      }
-
-      if p1 != none and p2 != none and cell != none {
-        let i1 = pars-i.at(p1)
-        let i2 = pars-i.at(p2)
-        cells.push(
-          (
-            elmt: elmt,
-            i1: calc.min(i1, i2),
-            i2: calc.max(i1, i2),
-            cell: cell
-          )
-        )
-      }
-    }
-  }
-
-  // Compute column widths
-  // Compute minimum widths for participant names and shapes
-  let widths = ()
-  for i in range(participants.len() - 1) {
-    let p1 = participants.at(i)
-    let p2 = participants.at(i + 1)
-    let m1 = participant.get-size(p1)
-    let m2 = participant.get-size(p2)
-    let w1 = m1.width
-    let w2 = m2.width
-    widths.push(w1 / 2pt + w2 / 2pt + PAR-SPACE)
-  }
-
-  // Compute minimum width for over notes
-  for n in elements.filter(e => (e.type == "note" and
-                                 e.side == "over" and 
-                                 type(e.pos) == str)) {
-    
-    let m = note.get-size(n)
-    let i = pars-i.at(n.pos)
-
-    if i < widths.len() {
-      widths.at(i) = calc.max(
-        widths.at(i),
-        m.width / 2 + NOTE-GAP
-      )
-    }
-    if i > 0 {
-      widths.at(i - 1) = calc.max(
-        widths.at(i - 1),
-        m.width / 2 + NOTE-GAP
-      )
-    }
-  }
-
-  // Compute minimum width for simple sequences (spanning 1 column)
-  for cell in cells.filter(c => c.i2 - c.i1 == 1) {
-    let m = measure(cell.cell)
-    widths.at(cell.i1) = calc.max(
-      widths.at(cell.i1),
-      m.width / 1pt + COMMENT-PAD
-    )
-  }
-
-  // Compute minimum width for self sequences
-  for cell in cells.filter(c => c.elmt.type == "seq" and c.i1 == c.i2) {
-    let m = measure(cell.cell)
-    let i = cell.i1
-    if cell.elmt.flip {
-      i -= 1
-    }
-    if 0 <= i and i < widths.len() {
-      widths.at(i) = calc.max(
-        widths.at(i),
-        m.width / 1pt + COMMENT-PAD
-      )
-    }
-  }
-
-  // Compute remaining widths for longer sequences (spanning multiple columns)
-  let multicol-cells = cells.filter(c => c.i2 - c.i1 > 1)
-  multicol-cells = multicol-cells.sorted(key: c => {
-    c.i1 * 1000 + c.i2
-  })
-  for cell in multicol-cells {
-    let m = measure(cell.cell)
-    widths.at(cell.i2 - 1) = calc.max(
-      widths.at(cell.i2 - 1),
-      m.width / 1pt + COMMENT-PAD - widths.slice(cell.i1, cell.i2 - 1).sum()
-    )
-  }
-
-  // Add lifeline widths
-  for (i, w) in widths.enumerate() {
-    let p1 = participants.at(i)
-    let p2 = participants.at(i + 1)
-    let w = w + p1.max-lifelines * LIFELINE-W / 2
-    if p2.max-lifelines != 0 {
-      w += LIFELINE-W / 2
-    }
-    widths.at(i) = w
-  }
-
-  for elmt in elements {
-    if elmt.type == "col" {
-      let i1 = pars-i.at(elmt.p1)
-      let i2 = pars-i.at(elmt.p2)
-      if calc.abs(i1 - i2) != 1 {
-        let i-min = calc.min(i1, i2)
-        let i-max = calc.max(i1, i2)
-        let others = pars-i.pairs()
-                           .sorted(key: p => p.last())
-                           .slice(i-min + 1, i-max)
-                           .map(p => "'" + p.first() + "'")
-                           .join(", ")
-        panic(
-          "Column participants must be consecutive (participants (" +
-          others +
-          ") are in between)"
-        )
-      }
-      let i = calc.min(i1, i2)
-
-      if elmt.width != auto {
-        widths.at(i) = normalize-units(elmt.width)
-      }
-
-      let width = widths.at(i)
-      width = calc.max(width, normalize-units(elmt.min-width))
-      if elmt.max-width != none {
-        width = calc.min(width, normalize-units(elmt.max-width))
-      }
-      widths.at(i) = width + normalize-units(elmt.margin)
-    }
-  }
-
-  return widths
-}
-
-#let render(participants, elements) = context canvas(length: 1pt, {
-  let shapes = ()
-  let pars-i = get-participants-i(participants)
-
-  let widths = get-columns-width(participants, elements)
-
-  // Compute each column's X position
-  let x-pos = (0,)
-  for width in widths {
-    x-pos.push(x-pos.last() + width)
-  }
-
-  let draw-seq = sequence.render.with(pars-i, x-pos, participants)
-  let draw-group = group.render.with()
-  let draw-else = group.render-else.with()
-  let draw-sep = separator.render.with(x-pos)
-  let draw-par = participant.render.with(x-pos)
-  let draw-note = note.render.with(pars-i, x-pos)
-  let draw-sync = sync.render.with(pars-i, x-pos, participants)
-  
-  // Draw participants (start)
-  for p in participants {
-    if p.from-start and not p.invisible and p.show-top {
-      shapes += draw-par(p)
-    }
-  }
-
-  let y = 0
-  let groups = ()
-  let lifelines = participants.map(_ => (
-    level: 0,
-    lines: ()
-  ))
-
-  // Draw elemnts
-  for elmt in elements {
-    // Sequences
-    if elmt.type == "seq" {
-      let shps
-      (y, lifelines, shps) = draw-seq(elmt, y, lifelines)
-      shapes += shps
-
-    // Groups (start) -> reserve space for labels + store position
-    } else if elmt.type == "grp" {
-      y -= Y-SPACE
-      let m = measure(
-        box(
-          elmt.name,
-          inset: (left: 5pt, right: 5pt, top: 3pt, bottom: 3pt),
-        )
-      )
-      groups = groups.map(g => {
-        if g.at(1).min-i == elmt.min-i { g.at(2) += 1 }
-        if g.at(1).max-i == elmt.max-i { g.at(3) += 1 }
-        g
-      })
-      if elmt.grp-type == "alt" {
-        elmt.insert("elses", ())
-      }
-      groups.push((y, elmt, 0, 0))
-      y -= m.height / 1pt
-    
-    // Groups (end) -> actual drawing
-    } else if elmt.type == "grp-end" {
-      y -= Y-SPACE
-      let (start-y, group, start-lvl, end-lvl) = groups.pop()
-      let x0 = x-pos.at(group.min-i) - start-lvl * 10 - 20
-      let x1 = x-pos.at(group.max-i) + end-lvl * 10 + 20
-      shapes += draw-group(x0, x1, start-y, y, group)
-
-      if group.grp-type == "alt" {
-        for (else-y, else-elmt) in group.elses {
-          shapes += draw-else(x0, x1, else-y, else-elmt)
-        }
-      }
-
-    // Alt's elses -> reserve space for label + store position
-    } else if elmt.type == "else" {
-      y -= Y-SPACE
-      let m = measure(text([\[#elmt.desc\]], weight: "bold", size: .8em))
-      groups.last().at(1).elses.push((
-        y, elmt
-      ))
-      y -= m.height / 1pt
-
-    // Separator
-    } else if elmt.type == "sep" {
-      let shps
-      (y, shps) = draw-sep(elmt, y)
-      shapes += shps
-    
-    // Gap
-    } else if elmt.type == "gap" {
-      y -= elmt.size
-
-    // Delay
-    } else if elmt.type == "delay" {
-      let y0 = y
-      let y1 = y - elmt.size
-      for (i, line) in lifelines.enumerate() {
-        line.lines.push(("delay-start", y0))
-        line.lines.push(("delay-end", y1))
-        lifelines.at(i) = line
-      }
-      if elmt.name != none {
-        let x0 = x-pos.first()
-        let x1 = x-pos.last()
-        shapes += draw.content(
-          ((x0 + x1) / 2, (y0 + y1) / 2),
-          anchor: "center",
-          elmt.name
-        )
-      }
-      y = y1
-    
-    // Event
-    } else if elmt.type == "evt" {
-      let par-name = elmt.participant
-      let i = pars-i.at(par-name)
-      let par = participants.at(i)
-      let line = lifelines.at(i)
-      if elmt.event == "disable" {
-        line.level -= 1
-        line.lines.push(("disable", y))
-      
-      } else if elmt.event == "destroy" {
-        line.lines.push(("destroy", y))
-      
-      } else if elmt.event == "enable" {
-        line.level += 1
-        line.lines.push(("enable", y, elmt.lifeline-style))
-      
-      } else if elmt.event == "create" {
-        y -= CREATE-OFFSET
-        shapes += participant.render(x-pos, par, y: y)
-        line.lines.push(("create", y))
-      }
-      lifelines.at(i) = line
-    
-    // Note
-    } else if elmt.type == "note" {
-      if not elmt.linked {
-        if not elmt.aligned {
-          y -= Y-SPACE
-        }
-        let shps
-        (y, shps) = draw-note(elmt, y, lifelines)
-        shapes += shps
-      }
-
-    // Synched sequences
-    } else if elmt.type == "sync" {
-      let shps
-      (y, lifelines, shps) = draw-sync(elmt, y, lifelines)
-      shapes += shps
-    }
-  }
-
-  y -= Y-SPACE
-
-  // Draw vertical lines + lifelines + end participants
-  shapes += draw.on-layer(-1, {
-    if DEBUG-INVISIBLE {
-      for p in participants.filter(p => p.invisible) {
-        let color = if p.name.starts-with("?") {green} else if p.name.ends-with("?") {red} else {blue}
-        let x = x-pos.at(p.i)
-        draw.line(
-          (x, 0),
-          (x, y),
-          stroke: (paint: color, dash: "dotted")
-        )
-        draw.content(
-          (x, 0),
-          p.display-name,
-          anchor: "west",
-          angle: 90deg
-        )
-      }
-    }
-    
-    for p in participants.filter(p => not p.invisible) {
-      let x = x-pos.at(p.i)
-
-      // Draw vertical line
-      let last-y = 0
-
-      let rects = ()
-      let destructions = ()
-      let lines = ()
-
-      // Compute lifeline rectangles + destruction positions
-      for line in lifelines.at(p.i).lines {
-        let event = line.first()
-        if event == "create" {
-          last-y = line.at(1)
-
-        } else if event == "enable" {
-          if lines.len() == 0 {
-            draw.line(
-              (x, last-y),
-              (x, line.at(1)),
-              stroke: p.line-stroke
-            )
-          }
-          lines.push(line)
-        
-        } else if event == "disable" or event == "destroy" {
-          let lvl = 0
-          if lines.len() != 0 {
-            let l = lines.pop()
-            lvl = lines.len()
-            rects.push((
-              x + lvl * LIFELINE-W / 2,
-              l.at(1),
-              line.at(1),
-              l.at(2)
-            ))
-            last-y = line.at(1)
-          }
-
-          if event == "destroy" {
-            destructions.push((x + lvl * LIFELINE-W / 2, line.at(1)))
-          }
-        } else if event == "delay-start" {
-          draw.line(
-            (x, last-y),
-            (x, line.at(1)),
-            stroke: p.line-stroke
-          )
-          last-y = line.at(1)
-        } else if event == "delay-end" {
-          draw.line(
-            (x, last-y),
-            (x, line.at(1)),
-            stroke: (
-              dash: "loosely-dotted",
-              paint: gray.darken(40%),
-              thickness: .8pt
-            )
-          )
-          last-y = line.at(1)
-        }
-      }
-
-      draw.line(
-        (x, last-y),
-        (x, y),
-        stroke: p.line-stroke
-      )
-
-      // Draw lifeline rectangles (reverse for bottom to top)
-      for rect in rects.rev() {
-        let (cx, y0, y1, style) = rect
-        let style = get-style("lifeline", style)
-        draw.rect(
-          (cx - LIFELINE-W / 2, y0),
-          (cx + LIFELINE-W / 2, y1),
-          ..style
-        )
-      }
-
-      // Draw lifeline destructions
-      for dest in destructions {
-        let (cx, cy) = dest
-        draw.line((cx - 8, cy - 8), (cx + 8, cy + 8), stroke: COL-DESTRUCTION + 2pt)
-        draw.line((cx - 8, cy + 8), (cx + 8, cy - 8), stroke: COL-DESTRUCTION + 2pt)
-      }
-
-      // Draw participants (end)
-      if p.show-bottom {
-        draw-par(p, y: y, bottom: true)
-      }
-    }
-  })
-
-  shapes
-})

src/separator.typ

@@ -1,63 +0,0 @@
-#import "/src/cetz.typ": draw
-#import "consts.typ": *
-
-#let _sep(name) = {
-  return ((
-    type: "sep",
-    name: name
-  ),)
-}
-
-#let _delay(name: none, size: 30) = {
-  return ((
-    type: "delay",
-    name: name,
-    size: size
-  ),)
-}
-
-#let render(x-pos, elmt, y) = {
-  let shapes = ()
-  y -= Y-SPACE
-
-  let x0 = x-pos.first() - 20
-  let x1 = x-pos.last() + 20
-  let m = measure(
-    box(
-      elmt.name,
-      inset: (left: 3pt, right: 3pt, top: 5pt, bottom: 5pt)
-    )
-  )
-  let w = m.width / 1pt
-  let h = m.height / 1pt
-  let cx = (x0 + x1) / 2
-  let xl = cx - w / 2
-  let xr = cx + w / 2
-
-  y -= h / 2
-  shapes += draw.rect(
-    (x0, y),
-    (x1, y - 3),
-    stroke: none,
-    fill: white
-  )
-  shapes += draw.line((x0, y), (x1, y))
-  //shapes += draw.line((x0, y), (xl, y))
-  //shapes += draw.line((xr, y), (x1, y))
-  y -= 3
-  shapes += draw.line((x0, y), (x1, y))
-  //shapes += draw.line((x0, y), (xl, y))
-  //shapes += draw.line((xr, y), (x1, y))
-  shapes += draw.content(
-    ((x0 + x1) / 2, y + 1.5),
-    elmt.name,
-    anchor: "center",
-    padding: (5pt, 3pt),
-    frame: "rect",
-    fill: COL-SEP-NAME
-  )
-  y -= h / 2
-
-  let r = (y, shapes)
-  return r
-}

src/sequence.typ

@@ -1,51 +1,4 @@
-#import "/src/cetz.typ": draw, vector
-#import "consts.typ": *
-#import "participant.typ"
-#import "note.typ"
-
-#let get-arrow-marks(sym, color) = {
-  if sym == none {
-    return none
-  }
-  if type(sym) == array {
-    return sym.map(s => get-arrow-marks(s, color))
-  }
-  (
-    "": none,
-    ">": (symbol: ">", fill: color),
-    ">>": (symbol: "straight"),
-    "\\": (symbol: ">", fill: color, harpoon: true, flip: true),
-    "\\\\": (symbol: "straight", harpoon: true, flip: true),
-    "/": (symbol: ">", fill: color, harpoon: true),
-    "//": (symbol: "straight", harpoon: true),
-    "x": none,
-    "o": none,
-  ).at(sym)
-}
-
-#let reverse-arrow-mark(mark) = {
-  if type(mark) == array {
-    return mark.map(m => reverse-arrow-mark(m))
-  }
-  let mark2 = mark
-  if type(mark) == dictionary and mark.at("harpoon", default: false) {
-    let flipped = mark.at("flip", default: false)
-    mark2.insert("flip", not flipped)
-  }
-  return mark2
-}
-
-#let is-tip-of-type(type_, tip) = {
-  if type(tip) == str and tip == type_ {
-    return true
-  }
-  if type(tip) == array and tip.contains(type_) {
-    return true
-  }
-  return false
-}
-#let is-circle-tip = is-tip-of-type.with("o")
-#let is-cross-tip = is-tip-of-type.with("x")
+#import "core/draw/sequence.typ"
 
 #let _seq(
   p1,
@@ -68,6 +21,7 @@
 ) = {
   return ((
     type: "seq",
+    draw: sequence.render,
     p1: p1,
     p2: p2,
     comment: comment,
@@ -94,294 +48,3 @@
     comment: comment
   ),)
 }
-
-#let render(pars-i, x-pos, participants, elmt, y, lifelines) = {
-  let shapes = ()
-
-  y -= Y-SPACE
-
-  let i1 = pars-i.at(elmt.p1)
-  let i2 = pars-i.at(elmt.p2)
-  let width = calc.abs(x-pos.at(i1) - x-pos.at(i2))
-
-  let h = 0
-  let comment = if elmt.comment == none {none} else {
-    let w = calc.min(width * 1pt, measure(elmt.comment).width)
-    box(
-      width: if i1 == i2 {auto} else {w},
-      elmt.comment
-    )
-  }
-  // Reserve space for comment
-  if comment != none {
-    h = calc.max(h, measure(comment).height / 1pt + 6)
-  }
-  if "linked-note" in elmt {
-    h = calc.max(h, note.get-size(elmt.linked-note).height / 2)
-  }
-  y -= h
-
-  let start-info = (
-    i: i1,
-    x: x-pos.at(i1),
-    y: y,
-    ll-lvl: lifelines.at(i1).level * LIFELINE-W / 2
-  )
-  let end-info = (
-    i: i2,
-    x: x-pos.at(i2),
-    y: y,
-    ll-lvl: lifelines.at(i2).level * LIFELINE-W / 2
-  )
-  let slant = if elmt.slant == auto {
-    DEFAULT-SLANT
-  } else if elmt.slant != none {
-    elmt.slant
-  } else {
-    0
-  }
-  end-info.y -= slant
-  if elmt.p1 == elmt.p2 {
-    end-info.y -= 10
-  }
-
-  if elmt.disable-src {
-    let src-line = lifelines.at(i1)
-    src-line.level -= 1
-    src-line.lines.push(("disable", start-info.y))
-    lifelines.at(i1) = src-line
-  }
-  if elmt.destroy-src {
-    let src-line = lifelines.at(i1)
-    src-line.lines.push(("destroy", start-info.y))
-    lifelines.at(i1) = src-line
-  }
-  if elmt.disable-dst {
-    let dst-line = lifelines.at(i2)
-    dst-line.level -= 1
-    dst-line.lines.push(("disable", end-info.y))
-    lifelines.at(i2) = dst-line
-  }
-  if elmt.destroy-dst {
-    let dst-line = lifelines.at(i2)
-    dst-line.lines.push(("destroy", end-info.y))
-    lifelines.at(i2) = dst-line
-  }
-  if elmt.enable-dst {
-    let dst-line = lifelines.at(i2)
-    dst-line.level += 1
-    lifelines.at(i2) = dst-line
-  }
-  if elmt.create-dst {
-    let par = participants.at(i2)
-    let m = measure(box(par.display-name))
-    let f = if i1 > i2 {-1} else {1}
-    end-info.x -= (m.width + PAR-PAD.last() * 2) / 2pt * f
-    shapes += participant.render(x-pos, par, y: end-info.y)
-  }
-
-  end-info.ll-lvl = lifelines.at(i2).level * LIFELINE-W / 2
-
-  // Compute left/right position at start/end
-  start-info.insert("lx", start-info.x)
-  if start-info.ll-lvl != 0 { start-info.lx -= LIFELINE-W / 2 }
-  end-info.insert("lx", end-info.x)
-  if end-info.ll-lvl != 0 { end-info.lx -= LIFELINE-W / 2 }
-
-  start-info.insert("rx", start-info.x + start-info.ll-lvl)
-  end-info.insert("rx", end-info.x + end-info.ll-lvl)
-
-  // Choose correct points to link
-  let x1 = start-info.rx
-  let x2 = end-info.lx
-
-  if (start-info.i > end-info.i) {
-    x1 = start-info.lx
-    x2 = end-info.rx
-  }
-
-  let style = (
-    mark: (
-      start: get-arrow-marks(elmt.start-tip, elmt.color),
-      end: get-arrow-marks(elmt.end-tip, elmt.color),
-      scale: 1.2
-    ),
-    stroke: (
-      dash: if elmt.dashed {(2pt,2pt)} else {"solid"},
-      paint: elmt.color,
-      thickness: .5pt
-    )
-  )
-
-  let y0 = start-info.y
-  if "linked-note" in elmt {
-    let shps = note.render(pars-i, x-pos, elmt.linked-note, start-info.y, lifelines).last()
-    shapes += shps
-  }
-
-  let flip-mark = end-info.i <= start-info.i
-  if elmt.flip {
-    flip-mark = not flip-mark
-  }
-  if flip-mark {
-    style.mark.end = reverse-arrow-mark(style.mark.end)
-  }
-
-  let pts
-  let comment-pt
-  let comment-anchor
-  let comment-angle = 0deg
-
-  if elmt.p1 == elmt.p2 {
-    if elmt.flip {
-      x1 = start-info.lx
-    } else {
-      x2 = end-info.rx
-    }
-
-    let x-mid = if elmt.flip {
-      calc.min(x1, x2) - 20
-    } else {
-      calc.max(x1, x2) + 20
-    }
-
-    pts = (
-      (x1, start-info.y),
-      (x-mid, start-info.y),
-      (x-mid, end-info.y),
-      (x2, end-info.y)
-    )
-
-    if comment != none {
-      comment-anchor = (
-        start: if x-mid < x1 {"south-east"} else {"south-west"},
-        end: if x-mid < x1 {"south-west"} else {"south-east"},
-        left: "south-west",
-        right: "south-east",
-        center: "south",
-      ).at(elmt.comment-align)
-
-      comment-pt = (
-        start: pts.first(),
-        end: pts.at(1),
-        left: if x-mid < x1 {pts.at(1)} else {pts.first()},
-        right: if x-mid < x1 {pts.first()} else {pts.at(1)},
-        center: (pts.first(), 50%, pts.at(1))
-      ).at(elmt.comment-align)
-    }
-
-  } else {
-    pts = (
-      (x1, start-info.y),
-      (x2, end-info.y)
-    )
-
-    if comment != none {
-      let start-pt = pts.first()
-      let end-pt = pts.last()
-      if elmt.start-tip != "" {
-        start-pt = (pts.first(), COMMENT-PAD, pts.last())
-      }
-      if elmt.end-tip != "" {
-        end-pt = (pts.last(), COMMENT-PAD, pts.first())
-      }
-
-      comment-pt = (
-        start: start-pt,
-        end: end-pt,
-        left: if x2 < x1 {end-pt} else {start-pt},
-        right: if x2 < x1 {start-pt} else {end-pt},
-        center: (start-pt, 50%, end-pt)
-      ).at(elmt.comment-align)
-
-      comment-anchor = (
-        start: if x2 < x1 {"south-east"} else {"south-west"},
-        end: if x2 < x1 {"south-west"} else {"south-east"},
-        left: "south-west",
-        right: "south-east",
-        center: "south",
-      ).at(elmt.comment-align)
-    }
-
-    let (p1, p2) = pts
-    if x2 < x1 {
-      (p1, p2) = (p2, p1)
-    }
-    comment-angle = vector.angle2(p1, p2)
-  }
-
-  // Start circle tip
-  if is-circle-tip(elmt.start-tip) {
-    shapes += draw.circle(pts.first(), radius: CIRCLE-TIP-RADIUS, stroke: none, fill: elmt.color, name: "_circle-start-tip")
-    pts.at(0) = "_circle-start-tip"
-  
-  // Start cross tip
-  } else if is-cross-tip(elmt.start-tip) {
-    let size = CROSS-TIP-SIZE
-    let cross-pt = (pts.first(), size * 2, pts.at(1))
-    shapes += draw.line(
-      (rel: (-size, -size), to: cross-pt),
-      (rel: (size, size), to: cross-pt),
-      stroke: elmt.color + 1.5pt
-    )
-    shapes += draw.line(
-      (rel: (-size, size), to: cross-pt),
-      (rel: (size, -size), to: cross-pt),
-      stroke: elmt.color + 1.5pt
-    )
-    pts.at(0) = cross-pt
-  }
-
-  // End circle tip
-  if is-circle-tip(elmt.end-tip) {
-    shapes += draw.circle(pts.last(), radius: 3, stroke: none, fill: elmt.color, name: "_circle-end-tip")
-    pts.at(pts.len() - 1) = "_circle-end-tip"
-  
-  // End cross tip
-  } else if is-cross-tip(elmt.end-tip) {
-    let size = CROSS-TIP-SIZE
-    let cross-pt = (pts.last(), size * 2, pts.at(pts.len() - 2))
-    shapes += draw.line(
-      (rel: (-size, -size), to: cross-pt),
-      (rel: (size, size), to: cross-pt),
-      stroke: elmt.color + 1.5pt
-    )
-    shapes += draw.line(
-      (rel: (-size, size), to: cross-pt),
-      (rel: (size, -size), to: cross-pt),
-      stroke: elmt.color + 1.5pt
-    )
-    pts.at(pts.len() - 1) = cross-pt
-  }
-
-  shapes += draw.line(..pts, ..style)
-
-  if comment != none {
-    shapes += draw.content(
-      comment-pt,
-      comment,
-      anchor: comment-anchor,
-      angle: comment-angle,
-      padding: 3pt
-    )
-  }
-
-  if elmt.create-dst {
-    let dst-line = lifelines.at(i2)
-    dst-line.lines.push(("create", end-info.y))
-    lifelines.at(i2) = dst-line
-  }
-  if elmt.enable-dst {
-    let dst-line = lifelines.at(i2)
-    dst-line.lines.push(("enable", end-info.y, elmt.lifeline-style))
-    lifelines.at(i2) = dst-line
-  }
-
-  if "linked-note" in elmt {
-    let m = note.get-size(elmt.linked-note)
-    end-info.y = calc.min(end-info.y, y0 - m.height / 2)
-  }
-
-  let r = (end-info.y, lifelines, shapes)
-  return r
-}

src/sync.typ

@@ -1,27 +0,0 @@
-#import "sequence.typ"
-
-#let _sync(elmts) = {
-  return ((
-    type: "sync",
-    elmts: elmts
-  ),)
-}
-
-#let render(pars-i, x-pos, participants, elmt, y, lifelines) = {
-  let draw-seq = sequence.render.with(pars-i, x-pos, participants)
-
-  let shapes = ()
-
-  let end-y = y
-
-  for e in elmt.elmts {
-    let yi
-    let shps
-    (yi, lifelines, shps) = draw-seq(e, y, lifelines)
-    shapes += shps
-    end-y = calc.min(end-y, yi)
-  }
-
-  let r = (end-y, lifelines, shapes)
-  return r
-}