From 4436c7fb618901585ca1e342013ded0aec246002 Mon Sep 17 00:00:00 2001
From: enricobuehler <buehler@unom.io>
Date: Wed, 22 Jul 2026 17:19:16 +0200
Subject: [PATCH] fix(host/stream): composite mode re-blends the LIVE cursor on
 repeat ticks
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The frame-attached overlay is the pointer position at the last damage
frame; repeats re-encoding a static desktop froze the blended cursor
between redraws — on-glass the composite-mode cursor stuttered while
window drags (constant damage) were smooth. Refresh the repeat's overlay
from Capturer::cursor each tick so pointer-only motion re-blends at tick
rate — the bandwidth the pre-channel embedded mode already paid. Linux
only: the Windows capturer composites internally and its frames must
never carry an overlay a blend path would double-draw.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 crates/punktfunk-host/src/native/stream.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/crates/punktfunk-host/src/native/stream.rs b/crates/punktfunk-host/src/native/stream.rs
index cab78b62..774e2789 100644
--- a/crates/punktfunk-host/src/native/stream.rs
+++ b/crates/punktfunk-host/src/native/stream.rs
@@ -2063,6 +2063,20 @@ pub(super) fn virtual_stream(ctx: SessionContext, prepared: Option<PreparedDispl
                 );
                 // The client draws the pointer — a blend-capable encoder must not also draw it.
                 frame.cursor = None;
+            } else {
+                // Host composites (Linux): the encoder blend IS the composite mechanism, but the
+                // frame-attached overlay is the position at the LAST DAMAGE frame — repeats
+                // re-encoding a static desktop froze the blended pointer between redraws
+                // (on-glass: composite cursor stuttered while window drags, constant damage,
+                // were smooth). Refresh the repeat's overlay from the capturer's LIVE cursor so
+                // pointer-only motion re-blends at tick rate — the same bandwidth the pre-channel
+                // embedded mode paid, where the compositor damaged frames for cursor moves.
+                // NOT Windows: its capturer composites internally (cursor_blend.rs) and frames
+                // must never carry an overlay a blend path would double-draw.
+                #[cfg(not(target_os = "windows"))]
+                if let Some(live) = capturer.cursor() {
+                    frame.cursor = Some(live);
+                }
             }
         }
         // The overlay surfaces hidden pointers too (for the hint above) — strip them