ludic.anim: a transition may name a via one-shot - a request from from (the state last asked, or "*") to to goes by it when the rig carries its clip, and the one-shot's next hands on. The game's hiker picked sit_down / stand_up / board_boat / leave_boat in code; the set says it now. A via edge is not an edge for a request's own fade. animset_test holds it, with a via the rig has and one it has not.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.anim/set_follow.ludic

@@ -33,7 +33,7 @@ function as_blend(s: AnimSet, from: int, to: int) -> float {
   if s.transitions != null {
     for i in 0 .. len(s.transitions) {
       let tr = s.transitions[i]
-      if tr.when == null and tr.to == s.states[to].key and as_leaves(s, tr, from) { return tr.blend }
+      if tr.when == null and tr.via == "" and tr.to == s.states[to].key and as_leaves(s, tr, from) { return tr.blend }
     }
   }
   return s.states[to].blend

packages/ludic.anim/set_pick.ludic

@@ -11,8 +11,22 @@ export function animset_request(pl: AnimPlayer, key: string) -> void {
   if pl.set < 0 or key == pl.asked { return }
   let i = as_state(AnimSets[pl.set], key)
   if i < 0 { return }
+  let v = as_via(pl, key)
   pl.asked = key
   pl.want = i
+  if v >= 0 { pl.want = v }
+}
+
+# the one-shot a request goes by: a `via` edge from where the code last asked (or "*") to this state,
+# whose clip the rig carries; -1 for none
+function as_via(pl: AnimPlayer, key: string) -> int {
+  let s = AnimSets[pl.set]
+  if s.transitions == null { return -1 }
+  for i in 0 .. len(s.transitions) {
+    let tr = s.transitions[i]
+    if tr.via != "" and tr.to == key and (tr.from == "*" or tr.from == pl.asked) and animset_can(pl, tr.via) { return as_state(s, tr.via) }
+  }
+  return -1
 }
 
 # the state is in the set and the rig carries one of its clips: a one-shot with none is not asked for

packages/ludic.anim/set_records.ludic

@@ -38,6 +38,7 @@ export property AnimTransition {
   to: string = ""
   blend: float = 0.2
   @frame when: fn() -> bool = null
+  via: string = ""       # a one-shot the code's request goes by when the rig carries its clip (its next hands on to `to`)
 }
 
 # a graph for a kind of rig: its parameters, its states (the first is where it starts unless

packages/ludic.anim/tests/animset_test.ludic

@@ -124,4 +124,22 @@ program AnimSetTest {
     expect(not animset_can(pl, "bow"))
     expect(not animset_can(pl, "nope"))
   }
+
+  test "a request goes by its via one-shot when the rig carries it, which hands on; else straight there" (anim_st: mut AnimState, render3d_st: mut Render3dState) {
+    let sk = skin(render3d_st)
+    let pl = rig(anim_st)
+    animset_request(pl, "seat")
+    animset_tick(anim_st, pl, sk, 0.1)
+    expect(playing(pl) == "rig_wave")
+    animset_tick(anim_st, pl, sk, 0.3)
+    animset_tick(anim_st, pl, sk, 0.3)
+    animset_tick(anim_st, pl, sk, 0.016)
+    expect(playing(pl) == "rig_hop")
+    animset_request(pl, "seat")
+    animset_tick(anim_st, pl, sk, 0.016)
+    expect(playing(pl) == "rig_hop")
+    animset_request(pl, "perch")
+    animset_tick(anim_st, pl, sk, 0.016)
+    expect(playing(pl) == "rig_walk")
+  }
 }

packages/ludic.anim/tests/sets.lres

@@ -1,5 +1,6 @@
 # sets.lres - the test's one set: a ground state picking by speed bands, a one-shot that hands back,
-# a hop the code never asks for, taken when toy_hops says so, and a bow no rig carries
+# a hop the code never asks for, taken when toy_hops says so, a bow no rig carries, and a seat and a
+# perch the code asks for by way of a one-shot (settle, which the rig has; bow, which it has not)
 toy {
   entry: "ground"
   params: ["speed"]
@@ -15,7 +16,14 @@ toy {
     },
     { key: "wave", loop: false, next: "ground", choices: [{ clip: "wave" }] },
     { key: "hop", choices: [{ clip: "hop" }] },
-    { key: "bow", loop: false, next: "ground", choices: [{ clip: "bow" }] }
+    { key: "bow", loop: false, next: "ground", choices: [{ clip: "bow" }] },
+    { key: "settle", loop: false, next: "seat", choices: [{ clip: "wave" }] },
+    { key: "seat", choices: [{ clip: "hop" }] },
+    { key: "perch", choices: [{ clip: "walk" }] }
+  ]
+  transitions: [
+    { from: "ground", to: "hop", blend: 0.1, when: fn toy_hops },
+    { from: "*", to: "seat", via: "settle" },
+    { from: "*", to: "perch", via: "bow" }
   ]
-  transitions: [{ from: "ground", to: "hop", blend: 0.1, when: fn toy_hops }]
 }