angle: Update angle library

src/lib/angle.typ

@@ -4,6 +4,7 @@
 #import "../util.typ"
 #import "../coordinate.typ"
 #import "../anchor.typ" as anchor_
+#import "/src/draw.typ"
 
 // Angle default-style
 #let default-style = (
@@ -14,6 +15,29 @@
   mark: styles.default.mark,
 )
 
+/// Draw an angle between `a` and `b` through origin `origin`
+///
+/// *Style Root:* `angle`
+///
+/// *Anchors*
+/// / `"a"`: Point a
+/// / `"b"`: Point b
+/// / `"origin"`: Origin
+/// / `"label"`: Label center
+/// / `"start"`: Arc start
+/// / `"end"`: Arc end
+///
+/// You can use the `radius` and `label-radius` style-keys to set
+/// the angle and label radius.
+///
+/// - origin (coordinate): Angle origin
+/// - a (coordinate): Coordinate of side a
+/// - b (coordinate): Coordinate of side b
+/// - inner (bool): Draw the smaller (inner) angle
+/// - label (none,content,function): Draw a label at the angles "label" anchor.
+///   If label is a function, it gets the angle value passed as argument.
+/// - name: (none,string): Element value
+/// - ..style (style): Style
 #let angle(
   origin,
   a,
@@ -22,112 +46,65 @@
   label: none,
   name: none,
   ..style
-) = {
-  let style = style.named()
+) = draw.group(name: name, ctx => {
+  let style = styles.resolve(ctx.style, style.named(), base: default-style, root: "angle")
+  let (ctx, origin, a, b) = coordinate.resolve(ctx, origin, a, b)
 
-  return (ctx => {
-    let style = styles.resolve(ctx.style, style, root: "angle", base: default-style)
-    let (ctx, origin, a, b) = coordinate.resolve(ctx, origin, a, b)
-    assert(
-      origin.at(2, default: 0) == 0 and
-      a.at(2, default: 0) == 0 and
-      b.at(2, default: 0) == 0,
-      message: "FIXME: Angle only works for 2D coordinates."
-    )
-    let (s, e, ss) = {
-      let s = vector.angle2(origin, a) * -1
-      if s < 0deg { s += 360deg }
-      let e = vector.angle2(origin, b) * -1
-      if e < 0deg { e += 360deg }
+  assert(origin.at(2) == a.at(2) and a.at(2) == b.at(2),
+    message: "Angle z coordinates of all three points must be equal")
 
-      if s > e {
-        (s, e) = (e, s)
-      }
+  let (s, e, ss) = {
+    let s = vector.angle2(origin, a) * -1
+    if s < 0deg { s += 360deg }
+    let e = vector.angle2(origin, b) * -1
+    if e < 0deg { e += 360deg }
+
+    if s > e {
+      (s, e) = (e, s)
+    }
 
-      if inner == true {
-        let d = vector.angle(a, origin, b) 
-        if e - s > 180deg {
-          (s, e) = (e, e + d)
-        } else {
-          (s, e) = (s, s + d)
-        }
-      } else if inner == false {
-        if e - s < 180deg {
-          let d = 360deg - vector.angle(a, origin, b) 
-          (s, e) = (e, e + d)
-        }
+    if inner == true {
+      let d = vector.angle(a, origin, b)
+      if e - s > 180deg {
+        (s, e) = (e, e + d)
+      } else {
+        (s, e) = (s, s + d)
+      }
+    } else if inner == false {
+      if e - s < 180deg {
+        let d = 360deg - vector.angle(a, origin, b)
+        (s, e) = (e, e + d)
       }
-      (s, e, (s + e) / 2)
     }
-    let (x, y, z) = origin
-    let (r, _) = util.resolve-radius(style.radius).map(util.resolve-number.with(ctx))
-    let (ra, _) = util.resolve-radius(style.label-radius).map(util.resolve-number.with(ctx))
-    let start = (x + r * calc.cos(s), y + r * calc.sin(s), z)
-    let end = (x + r * calc.cos(e), y + r * calc.sin(e), z)
-    let pt-label = (x + ra * calc.cos(ss), y + ra * calc.sin(ss), z)
+    (s, e, (s + e) / 2)
+  }
 
-    let drawables = ()
+  let (r, _) = util.resolve-radius(style.radius).map(util.resolve-number.with(ctx))
+  let (ra, _) = util.resolve-radius(style.label-radius).map(util.resolve-number.with(ctx))
 
-    let (marks, draw-pt, draw-s, draw-e) = if style.mark != none {
-      import "/src/mark.typ" as mark_
-      mark_.place-marks-along-arc(ctx, s, e, start, r, r, style, style.mark)
-    } else {
-      (none, start, s, e)
-    }
+  let label-pt = vector.add(origin, (calc.cos(ss) * ra, calc.sin(ss) * ra, 0))
+  let start-pt = vector.add(origin, (calc.cos(s) * r, calc.sin(s) * r, 0))
+  let end-pt = vector.add(origin, (calc.cos(e) * r, calc.sin(e) * r, 0))
+  draw.anchor("origin", origin)
+  draw.anchor("label", label-pt)
+  draw.anchor("start", start-pt)
+  draw.anchor("end", end-pt)
+  draw.anchor("a", a)
+  draw.anchor("b", b)
+
+  if s != e {
     if style.fill != none {
-      drawables.push(
-        drawable.arc(..draw-pt, draw-s, draw-e, r, r, mode: "PIE", fill: style.fill, stroke: none)
-      )
+      draw.arc(origin, start: s, stop: e, anchor: "origin",
+        name: "arc", ..style, radius: r, mode: "PIE", mark: none, stroke: none)
     }
     if style.stroke != none {
-      drawables.push(
-        drawable.arc(..draw-pt, draw-s, draw-e, r, r, mode: "OPEN", fill: none, stroke: style.stroke)
-      )
-    }
-    if marks != none {
-      drawables += marks
+      draw.arc(origin, start: s, stop: e, anchor: "origin",
+        name: "arc", ..style, radius: r, fill: none)
     }
+  }
 
-    let (x, y, z) = start
-    let label = if type(label) == function { label(e - s) } else { label }
-    if label != none {
-      let (lx, ly, ..) = pt-label
-      let (w, h) = util.measure(ctx, label)
-      drawables.push(
-        drawable.content(
-          (lx, ly, 0),
-          w, 
-          h,
-          label
-        )
-      )
-    }
-
-    let (transform, anchors) = anchor_.setup(
-      anchor => {
-        (
-          origin: origin,
-          a: a,
-          b: b,
-          start: start,
-          end: end,
-          label: pt-label
-        ).at(anchor)
-      },
-      ("origin", "a", "b", "start", "end", "label"),
-      transform: ctx.transform,
-      name: name,
-      default: "label"
-    )
-
-    return (
-      ctx: ctx,
-      name: name,
-      anchors: anchors,
-      drawables: drawable.apply-transform(
-        transform,
-        drawables
-      )
-    )
-  },)
-}
+  let label = if type(label) == function { label(e - s) } else { label }
+  if label != none {
+    draw.content(label-pt, label)
+  }
+})