FPP Connect: stop wiping FPP-owned universe output settings

Uploading UDP outputs regenerated the universes channel output from scratch
and rescued only two keys (interface, pacingRate) out of the config already
on the FPP, so FPP10's Sending mode was always lost and the global Pacing
setting reverted to FPP's 90Mbps default whenever the rescue did not run -
the pacing carry-forward was gated on the discovered FPP version, which is
zero for an instance whose version probe failed.

Invert it: rebuild the universes output on top of the existing one and
overwrite only the keys xLights owns (type, enabled, timeout, startChannel,
channelCount, universes). The source interface, sending mode, global and
per-controller pacing, and anything a newer FPP adds now carry through
untouched. The internal pacing-authoritative hint is also stripped when the
existing config could not be read, instead of leaking into the upload.

Fixes FalconChristmas/fpp#2845

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: dkulp

README.txt

@@ -12,6 +12,9 @@ XLIGHTS/NUTCRACKER RELEASE NOTES
 ---------------------------------
 2026.16  August ??, 2026
 
+    -bug (dkulp)                 FPP Connect: uploading UDP outputs no longer resets FPP10's E1.31 Pacing
+                                 and Sending mode - every setting on the universes output that xLights
+                                 does not own is now carried forward unchanged
     -enh (derwin12)              Windows: enhance Generate Custom Model for USB webcam to generate an .xmodel (#3791)
     -bug (dkulp)                 Windows/Linux: fix crash on startup when the machine falls back to the
                                  software OpenGL 1.1 rasterizer - the preview now draws nothing instead

plans/platform-parity/07-controllers-setup-upload.md

@@ -155,7 +155,7 @@ code is dark.
 | 63 | FPP Connect — HostName/IP column + sort | Header `FPPConnectDialog.cpp:260`; right-click "Sort by HostName" / "Sort by IP Address" `:1004-1012`, persisted as `FPPConnectLocationSort` `:277` | 🟡 | iPad shows host/IP in `FPPInstance.displayName`/`subtitle` (`FPPConnectSheet.swift:77-88`) but offers no sort control; grep `sort` in `FPPConnectSheet.swift` finds no user-facing sort. |
 | 64 | FPP Connect — Mode column | Header `FPPConnectDialog.cpp:262` | ✅ | `FPPInstance.mode` `FPPConnectSheet.swift:35-107`, rendered in `subtitle` `:81-88`. |
 | 65 | FPP Connect — Media upload toggle | Header `FPPConnectDialog.cpp:263`; right-click Select All / Deselect All (`MediaPopupMenu` `:264`) | 🟡 | `FPPInstanceConfig.uploadMedia` `FPPConnectSheet.swift:122`, toggle `:1021`, media path resolved via `document.mediaPath(forXsq:)` `:522`. Gap: no bulk select-all/none for the column. |
-| 66 | FPP Connect — UDP Out mode | Header `FPPConnectDialog.cpp:265`; None / All / Proxied | ✅ | `UDPOutMode` enum `FPPConnectSheet.swift:142-152` ("None"/"All Controllers"/"Proxied Only"), picker `:1047-1054`, applied via `document.applyConfig(toFPP:settings:progress:)` `:463-471`. |
+| 66 | FPP Connect — UDP Out mode | Header `FPPConnectDialog.cpp:265`; None / All / Proxied | ✅ | `UDPOutMode` enum `FPPConnectSheet.swift:142-152` ("None"/"All Controllers"/"Proxied Only"), picker `:1047-1054`, applied via `document.applyConfig(toFPP:settings:progress:)` `:463-471`. **2026-08-22:** `FPP::UploadUDPOut` now rebuilds the universes channel output on top of the one already on the FPP, replacing only the keys xLights owns (type/enabled/timeout/startChannel/channelCount/universes) so FPP10's source interface, Sending mode and global + per-controller Pacing survive the upload; shared core, so both platforms get it automatically. |
 | 67 | FPP Connect — "Add Proxies" | Header `FPPConnectDialog.cpp:266`; `inst->UploadControllerProxies(_outputManager)` `:1276` | ✅ | `uploadProxies` `FPPConnectSheet.swift:126`, toggle `:1029-1030`, in the config payload `:463-471`. |
 | 68 | FPP Connect — "Upload Outputs" / cape config | Header `FPPConnectDialog.cpp:267`; right-click Select All / Deselect All (`CapePopupMenu` `:433-440`, handler `:442-459`) | 🟡 | `uploadCape` `FPPConnectSheet.swift:125` — "Pixel Hat / Cape Outputs - <model>" when `inst.hasCape` `:1024-1027`, repurposed as "Upload Controller Config" for non-FPP devices `:1011-1016`. Gap: no Select All / Deselect All. |
 | 69 | FPP Connect — **FSEQ Type picker** | Header `FPPConnectDialog.cpp:269`; the per-instance widget depends on the device family — FPP gets V1 / V2 zstd / V2 Sparse/zstd / V2 Sparse/Uncompressed (`:657-660`) defaulting to **V2 zstd for a `master`-mode instance** and V2 Sparse/zstd otherwise (`:661`); Falcon V4/V5 + PowerDMX get V1 / V2 **zlib** / V2 Sparse/zlib / V2 Sparse/Uncompressed / V2 Uncompressed (`:671-675`, default `:676`); ESPixelStick and Genius are fixed at V2 Sparse/Uncompressed (`:680`) and everything else at V1 (`:682`). The chosen index is mapped to a codec id at upload (`:1382-1392` — FPP passes the index through, Falcon V4/V5 remaps 1→5 and 2→6, every other family is forced to 3), and persisted per-UUID as `FPPConnectUploadFSEQType_*` (`:1721-1726`, `:1771-1773`) | 🟡 | **The earlier missing-status evidence here overstated the impact and is corrected.** iPad discovery admits only `FPP_TYPE::FPP` and `FPP_TYPE::ESPIXELSTICK` — every other family is dropped by an explicit filter in the discovery path (`XLSequenceDocument.mm`, "iPad scope: FPP + ESPixelStick only"), so the claimed Falcon V4/V5 zstd-vs-zlib and Genius/PowerDMX type-2-vs-3 mis-sends were **unreachable**: those devices never enter `_fppInstances` and never receive an upload. Of the original claim only the master-mode case was real, and it is **fixed 2026-08-06**: a plain FPP now gets desktop's per-mode default (V2 zstd for a `master` instance, V2 Sparse/zstd otherwise, `FPPConnectDialog.cpp:661`) instead of always sparse; ESPixelStick keeps 3, which already matched. Remaining gap: no user-facing picker and no per-UUID persistence, so the desktop default is all you get. |

src-core/controllers/FPP.cpp

@@ -1518,72 +1518,76 @@ bool FPP::UploadUDPOut(const nlohmann::json &udp) {
     nlohmann::json orig;
     nlohmann::json newudp = udp;
 
-    if (GetURLAsJSON("/api/channel/output/universeOutputs", orig)) {
-        if (orig.contains("channelOutputs")) {
-            // FPP owns a few universe-output settings that xLights doesn't model
-            // (the network interface, and the packet-pacing/bandwidth caps used to
-            // throttle slower controllers). Carry those forward so regenerating the
-            // outputs file doesn't wipe them out. Pacing overrides are keyed by
-            // destination controller IP so they survive universe/start-channel
-            // renumbering; where a controller has several entries we keep the most
-            // conservative cap (FPP itself collapses to the lowest rate per IP).
-            // Per-output pacing only exists in FPP 10+.
-            bool const supportsPacing = IsVersionAtLeast(10, 0, 0);
-            std::map<std::string, int> pacingByAddress;
-            for (int x = 0; x < (int)orig["channelOutputs"].size(); x++) {
-                const auto& co = orig["channelOutputs"][x];
-                if (GetJSONStringValue(co, "type") != "universes") {
-                    continue;
-                }
-                if (co.contains("interface")) {
-                    newudp["channelOutputs"][0]["interface"] = GetJSONStringValue(co, "interface");
-                }
-                if (supportsPacing && co.contains("pacingRate")) {
-                    // output-level global pacing default
-                    newudp["channelOutputs"][0]["pacingRate"] = co["pacingRate"];
-                }
-                if (supportsPacing && co.contains("universes")) {
-                    for (const auto& u : co["universes"]) {
-                        if (!u.contains("pacingRate")) {
-                            continue;
-                        }
-                        std::string addr = GetJSONStringValue(u, "address");
-                        if (addr.empty()) {
-                            continue; // pacing only applies to unicast destinations
-                        }
-                        int rate = GetJSONIntValue(u, "pacingRate", -1);
-                        if (rate < 0) {
-                            continue;
-                        }
-                        auto it = pacingByAddress.find(addr);
-                        if (it == pacingByAddress.end()) {
-                            pacingByAddress[addr] = rate;
-                        } else if (rate > 0 && (it->second <= 0 || rate < it->second)) {
-                            it->second = rate; // a real cap beats "unlimited" (0); lower Mbps wins
-                        }
-                    }
+    // Per-output pacing only exists in FPP 10+.
+    bool const supportsPacing = IsVersionAtLeast(10, 0, 0);
+    std::map<std::string, int> pacingByAddress;
+
+    if (GetURLAsJSON("/api/channel/output/universeOutputs", orig) && orig.contains("channelOutputs")) {
+        // xLights only owns the universe list itself. Everything else on the
+        // universes channel output belongs to FPP (the source interface, the
+        // sending/threading mode, the packet-pacing/bandwidth cap used to throttle
+        // slower controllers, plus anything a newer FPP adds), so carry those keys
+        // forward rather than dropping them when the outputs file is regenerated.
+        static const std::unordered_set<std::string> xlOwnedKeys = {
+            "type", "enabled", "timeout", "startChannel", "channelCount", "universes"
+        };
+        // Per-universe pacing overrides are keyed by destination controller IP so they
+        // survive universe/start-channel renumbering; where a controller has several
+        // entries we keep the most conservative cap (FPP itself collapses to the
+        // lowest rate per IP).
+        for (int x = 0; x < (int)orig["channelOutputs"].size(); x++) {
+            const auto& co = orig["channelOutputs"][x];
+            if (GetJSONStringValue(co, "type") != "universes") {
+                continue;
+            }
+            for (const auto& [key, value] : co.items()) {
+                if (xlOwnedKeys.find(key) == xlOwnedKeys.end()) {
+                    newudp["channelOutputs"][0][key] = value;
                 }
             }
-            if (supportsPacing && newudp.contains("channelOutputs")) {
-                for (auto& co : newudp["channelOutputs"]) {
-                    if (!co.contains("universes")) {
+            if (supportsPacing && co.contains("universes")) {
+                for (const auto& u : co["universes"]) {
+                    if (!u.contains("pacingRate")) {
                         continue;
                     }
-                    for (auto& u : co["universes"]) {
-                        // Entries flagged authoritative (controller under full xLights
-                        // control) keep the xLights-set cap; others preserve whatever the
-                        // FPP already had. Strip the internal hint either way.
-                        bool const authoritative = u.contains("_xlPacingAuthoritative");
-                        u.erase("_xlPacingAuthoritative");
-                        if (authoritative) {
-                            continue;
-                        }
-                        std::string addr = GetJSONStringValue(u, "address");
-                        auto it = pacingByAddress.find(addr);
-                        if (!addr.empty() && it != pacingByAddress.end()) {
-                            u["pacingRate"] = it->second;
-                        }
+                    std::string addr = GetJSONStringValue(u, "address");
+                    if (addr.empty()) {
+                        continue; // pacing only applies to unicast destinations
+                    }
+                    int rate = GetJSONIntValue(u, "pacingRate", -1);
+                    if (rate < 0) {
+                        continue;
                     }
+                    auto it = pacingByAddress.find(addr);
+                    if (it == pacingByAddress.end()) {
+                        pacingByAddress[addr] = rate;
+                    } else if (rate > 0 && (it->second <= 0 || rate < it->second)) {
+                        it->second = rate; // a real cap beats "unlimited" (0); lower Mbps wins
+                    }
+                }
+            }
+        }
+    }
+    // The authoritative hint is internal to xLights and must be stripped whether or
+    // not the existing config could be read.
+    if (newudp.contains("channelOutputs")) {
+        for (auto& co : newudp["channelOutputs"]) {
+            if (!co.contains("universes")) {
+                continue;
+            }
+            for (auto& u : co["universes"]) {
+                // Entries flagged authoritative (controller under full xLights
+                // control) keep the xLights-set cap; others preserve whatever the
+                // FPP already had.
+                bool const authoritative = u.contains("_xlPacingAuthoritative");
+                u.erase("_xlPacingAuthoritative");
+                if (authoritative || !supportsPacing) {
+                    continue;
+                }
+                std::string addr = GetJSONStringValue(u, "address");
+                auto it = pacingByAddress.find(addr);
+                if (!addr.empty() && it != pacingByAddress.end()) {
+                    u["pacingRate"] = it->second;
                 }
             }
         }