From 757790debe338ef32809815e4149655b94eacbab Mon Sep 17 00:00:00 2001
From: Matthew Stanley <1379tech@gmail.com>
Date: Wed, 30 Sep 2026 21:38:17 -0700
Subject: [PATCH] Keep large screen-space composites anchored as one group

---
 runtime/include/ws_hud_anchor.h    |  4 +++-
 runtime/tests/test_ws_hud_anchor.c | 12 ++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/runtime/include/ws_hud_anchor.h b/runtime/include/ws_hud_anchor.h
index fc02cedc..2d035cae 100644
--- a/runtime/include/ws_hud_anchor.h
+++ b/runtime/include/ws_hud_anchor.h
@@ -9,7 +9,9 @@
 extern "C" {
 #endif
 
-#define WS_HUD_ANCHOR_TABLE_SIZE 256u
+/* Large screen-space composites can exceed 256 packets (MMX6 Ilumina).
+ * Keep both pending display buffers' pieces anchored together. */
+#define WS_HUD_ANCHOR_TABLE_SIZE 4096u
 #define WS_HUD_ANCHOR_PROBES 8u
 #define WS_HUD_ANCHOR_FRESH_FRAMES 2u
 
diff --git a/runtime/tests/test_ws_hud_anchor.c b/runtime/tests/test_ws_hud_anchor.c
index fc91c5a3..5f3a7089 100644
--- a/runtime/tests/test_ws_hud_anchor.c
+++ b/runtime/tests/test_ws_hud_anchor.c
@@ -69,6 +69,18 @@ int main(void) {
     assert(!ws_hud_anchor_lookup(tags, WS_HUD_ANCHOR_TABLE_SIZE,
                                  0x80010004u, packet, 4u, 20u, &anchor));
 
+    /* Two pending 1000-piece composites, with MMX6's 40-byte packet stride.
+     * Losing early arm pieces splits Ilumina when world origin shifts. */
+    for (uint32_t i = 0; i < 2000u; ++i)
+        ws_hud_anchor_insert(tags, WS_HUD_ANCHOR_TABLE_SIZE,
+                             0x10004u + i * 40u, 0, &guard, 30u + i / 1000u);
+    for (uint32_t i = 0; i < 2000u; ++i) {
+        anchor = 99;
+        assert(ws_hud_anchor_lookup(tags, WS_HUD_ANCHOR_TABLE_SIZE,
+                                    0x10004u + i * 40u, packet, 4u, 31u, &anchor));
+        assert(anchor == 0);
+    }
+
     puts("ws_hud_anchor_test: PASS");
     return 0;
 }