From 0dfb0748204e5b7d4942a140a1935f098e6c70c4 Mon Sep 17 00:00:00 2001
From: NetterSilver <133535268+Silvertree2010@users.noreply.github.com>
Date: Thu, 15 Oct 2026 23:07:39 +0000
Subject: [PATCH] Shift controller events by Delay in track.write_midi_rtp

Found while testing crates/engine/src/cmd/track_more.rs:370-392 (write_rtp); playback side: crates/mix/src/lib.rs:1526-1527

Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
---
 crates/engine/src/cmd/track_more.rs | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/crates/engine/src/cmd/track_more.rs b/crates/engine/src/cmd/track_more.rs
index 290a8d5a..9f547597 100644
--- a/crates/engine/src/cmd/track_more.rs
+++ b/crates/engine/src/cmd/track_more.rs
@@ -383,6 +383,10 @@ fn write_rtp(e: &mut Engine, p: &Value) -> Result<Value> {
                 n.start = n.start.saturating_add(r.delay_ticks).max(0);
                 notes += 1;
             }
+            // Playback delays controller events too, but ignores those before tick 0 (hidden by a start trim).
+            for c in sequence.ctrls.iter_mut().filter(|c| c.tick >= 0) {
+                c.tick = c.tick.saturating_add(r.delay_ticks).max(0);
+            }
             sequence.sort();
         }
         let pre = format!("rtp.{}.", t.0);
@@ -635,6 +639,31 @@ mod tests {
         assert!(!e.session().edit.values.keys().any(|k| k.starts_with(&format!("rtp.{}.", keys.0))));
     }
 
+    #[test]
+    fn rtp_delay_shifts_controller_events() {
+        use soundcraft_midi::{CtrlEvent, CtrlKind};
+        let mut e = crate::demo::demo_engine();
+        let keys = e.session().track_by_name("Keys").unwrap().id;
+        let s = e.session_mut();
+        if let Some(pl) = s.track_mut(keys).and_then(Track::playlist_mut)
+            && let ClipContent::Midi { sequence } = &mut pl.clips[0].content
+        {
+            sequence.ctrls.clear();
+            sequence.ctrls.push(CtrlEvent { tick: 100, channel: 0, kind: CtrlKind::Cc(7), value: 90 });
+            sequence.ctrls.push(CtrlEvent { tick: 200, channel: 0, kind: CtrlKind::PitchBend, value: 10 });
+            sequence.ctrls.push(CtrlEvent { tick: -30, channel: 0, kind: CtrlKind::Cc(1), value: 5 });
+        }
+        s.edit.values.insert(track_key("rtp", keys, "delay"), 50.0);
+        e.execute("edit.select", &json!({"tracks": [keys.0]})).unwrap();
+        e.execute("track.write_midi_rtp", &json!({})).unwrap();
+        let ClipContent::Midi { sequence } = &e.session().track(keys).unwrap().clips()[0].content else { panic!() };
+        let tick_of = |k: CtrlKind| sequence.ctrls.iter().find(|c| c.kind == k).map(|c| c.tick);
+        assert_eq!(tick_of(CtrlKind::Cc(7)), Some(150), "playback delayed the CC by 50 ticks; baked result must match");
+        assert_eq!(tick_of(CtrlKind::PitchBend), Some(250));
+        // Hidden by a start trim: playback ignores it, so baking leaves it alone.
+        assert_eq!(tick_of(CtrlKind::Cc(1)), Some(-30));
+    }
+
     #[test]
     fn trim_and_vca_coalesce() {
         let mut e = Engine::default();