Reuse held Spine poses and redeploy countdown textures (#434)

public/js/render/spine.js

@@ -31,6 +31,8 @@
 //                                         closing clip timed to end `in` s from now (a 重生's last clip ends with the
 //                                         重生), landing in `roles`
 //   update(dt)                            advances the skeleton (autoUpdate is off: one clock for everything)
+//   poseHeld()                            true while the pose cannot change (render/units.js then neither re-poses nor
+//                                         redraws the model, only advances `clock`)
 // Attack mode lasts until ~1.4 attack intervals without a new attack (a `once` cast and every attack of a
 // `clipPerAttack` actor: to the end of its clip), then the end clip (if any) and base — except the attacks of a skill
 // with its own idle clip, which go straight back to that idle: the skill's end clip closes the skill, not each spell of
@@ -160,6 +162,8 @@ export class SpineActor {
      */
     this.clipPerAttack = false;
     this.wound = false;           // clipPerAttack: wound up for the coming attack (windUp → attack)
+    this._applied = false;        // an update has posed the skeleton since its clip last changed (poseHeld)
+    this._appliedTint = undefined; // the tint that update put on the slots (pixi-spine applies `tint` in update)
     this._play(this._idleName(), true);
   }
 
@@ -310,6 +314,7 @@ export class SpineActor {
       if (start) e.trackTime = start;
     }
     this.current = name;
+    this._applied = false;
     return true;
   }
 
@@ -317,6 +322,7 @@ export class SpineActor {
     if (!this.has(name)) return false;
     const e = this.spine.state.addAnimation(0, name, loop, 0);
     if (e) e.timeScale = timeScale;
+    this._applied = false;
     return true;
   }
 
@@ -548,6 +554,24 @@ export class SpineActor {
     return 0;
   }
 
+  /**
+   * True while an update would draw the same pixels: a frozen model, or a dead one whose only clip — track 0, not
+   * looping, not mixing — has played out (the held end of a death clip; a skeleton without one holds its idle at
+   * timeScale 0). Only once an update has posed the current clip and put the current tint on the slots (pixi-spine applies
+   * `tint` in update: the grey of a knocked-out operator, a hit flash). Never while a form's closing clip or a wind-up is
+   * pending: those act on the clock.
+   */
+  poseHeld() {
+    if (!this._applied || this.spine.tint !== this._appliedTint || this.endClip || this.windUntil != null) return false;
+    if (this.frozen) return true;
+    if (this.mode !== 'die') return false;
+    const tracks = this.spine.state.tracks;
+    for (let i = 1; i < tracks.length; i++) if (tracks[i]) return false;
+    const e = tracks[0];
+    if (!e || e.loop || e.mixingFrom) return false;
+    return e.timeScale === 0 || e.trackTime >= e.animationEnd - e.animationStart;
+  }
+
   /** Revive (redeploy after death). */
   revive() {
     this.dead = false;
@@ -621,6 +645,8 @@ export class SpineActor {
       try { this.spine.update(dt); } catch { /* a broken skeleton must not stop the frame */ }
     }
     if (this.clipped && !this.clipOn) this._eyeMaskFallback();
+    this._applied = true;
+    this._appliedTint = this.spine.tint;
   }
 
   /**