refactored sequences, sync and gaps

src/core/draw/event.typ

@@ -0,0 +1,31 @@
+#import "../utils.typ": get-ctx, set-ctx
+#import "../../consts.typ": *
+
+#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)
+  } 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/participant.typ

@@ -0,0 +1,405 @@
+#import "../../consts.typ": *
+#import "../../cetz.typ": draw
+#import "../utils.typ": get-ctx, set-ctx, get-style
+
+#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/sequence.typ

@@ -0,0 +1,360 @@
+#import "../utils.typ": get-ctx, set-ctx
+#import "../../consts.typ": *
+#import "../../cetz.typ": draw, vector
+
+
+#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")
+
+#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
+    note.render(seq.linked-note, y: start-info.y)
+  }
+
+  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 "../utils.typ": get-ctx, set-ctx, is-elmt
+
+#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

@@ -379,13 +379,9 @@
   // Draw elements
   for elmt in elements {
     if not is-elmt(elmt) {
-      shapes.push(elmt)
+      (elmt,)
-
+    } else if "draw" in elmt and elmt.type != "par" {
-    // Sequences
+      (elmt.draw)(elmt)
-    } else 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" {
@@ -441,10 +437,6 @@
       (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
@@ -465,30 +457,6 @@
       }
       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 {
@@ -499,12 +467,6 @@
         (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
     }
   }
 

src/core/utils.typ

@@ -95,8 +95,9 @@
 
 #let set-ctx(func) = draw.set-ctx(c => {
   let ctx = c.shared-state.chronos
-  ctx = func(ctx)
+  let new-ctx = func(ctx)
-  c.shared-state.chronos = ctx
+  assert(new-ctx != none, message: "set-ctx must return a context!")
+  c.shared-state.chronos = new-ctx
   return c
 })
 

src/diagram.typ

@@ -1,13 +1,19 @@
-#import "core/utils.typ": fit-canvas
+#import "core/utils.typ": fit-canvas, set-ctx
 #import "core/renderer.typ": render
 #import "participant.typ" as participant: _par, PAR-SPECIALS
 #import "sequence.typ": _seq
-
+#import "core/draw/event.typ": render as evt-render
 #import "core/setup.typ": setup
 
+#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
   ),)
 }
@@ -15,6 +21,7 @@
 #let _evt(participant, event) = {
   return ((
     type: "evt",
+    draw: evt-render,
     participant: participant,
     event: event,
     lifeline-style: auto

src/participant.typ

@@ -1,6 +1,6 @@
 #import "/src/cetz.typ": draw
 #import "consts.typ": *
-#import "core/draw/participant.typ"
+#import "core/draw/participant.typ": render as par-render
 
 #let PAR-SPECIALS = "?[]"
 #let SHAPES = (
@@ -37,7 +37,7 @@
   }
   return ((
     type: "par",
-    draw: participant.render,
+    draw: par-render,
     name: name,
     display-name: if display-name == auto {name} else {display-name},
     from-start: from-start,

src/sequence.typ

@@ -2,50 +2,7 @@
 #import "consts.typ": *
 #import "participant.typ"
 #import "note.typ"
-
+#import "core/draw/sequence.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")
 
 #let _seq(
   p1,
@@ -68,6 +25,7 @@
 ) = {
   return ((
     type: "seq",
+    draw: sequence.render,
     p1: p1,
     p2: p2,
     comment: comment,
@@ -94,294 +52,3 @@
     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 +1,10 @@
 #import "sequence.typ"
+#import "core/draw/sync.typ"
 
 #let _sync(elmts) = {
   return ((
     type: "sync",
+    draw: sync.render,
     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
-}