Reduce moc parse time by 60% with lightweight MAVLink headers

.github/instructions/forward-declarations.instructions.md

@@ -0,0 +1,23 @@
+---
+applyTo: "src/**/*.h"
+description: "When performing a code review on C++ headers, check that heavy headers like Vehicle.h and QGCMAVLink.h are not included when a lightweight alternative or forward declaration suffices."
+---
+
+# Forward Declaration Rules for Headers
+
+Prefer forward declarations and lightweight type headers over including full class definitions.
+
+## Vehicle.h
+
+`Vehicle.h` is one of the heaviest headers in the codebase. Most headers that reference `Vehicle` only need:
+- A pointer/reference to Vehicle → `class Vehicle;` forward declaration
+- Vehicle type aliases → `#include "VehicleTypes.h"`
+
+Only include `Vehicle.h` if the header calls Vehicle methods, accesses Vehicle members, or inherits from Vehicle.
+
+## QGCMAVLink.h
+
+`QGCMAVLink.h` combines MAVLink enums, message types, and QGC-specific type aliases. Most headers only need one of these. Use the specific lightweight header instead:
+- `MAVLinkEnums.h` for enum constants
+- `MAVLinkMessageType.h` for `mavlink_message_t`
+- `QGCMAVLinkTypes.h` for `FirmwareClass_t`, `VehicleClass_t`

.github/instructions/mavlink-includes.instructions.md

@@ -0,0 +1,35 @@
+---
+applyTo: "src/**/*.h"
+description: "When performing a code review on C++ headers, enforce the MAVLink lightweight include hierarchy to keep moc parse times fast."
+---
+
+# MAVLink Include Rules for Headers
+
+C++ header files must use the **lightest possible** MAVLink include. Heavy includes in headers slow Qt moc parsing dramatically (~2.5s vs ~8ms per header).
+
+## Include Hierarchy (lightest to heaviest)
+
+| Header | Provides | Preprocessed Lines |
+|--------|----------|--------------------|
+| `MAVLinkEnums.h` | All 253 MAVLink enum typedefs (MAV_CMD, MAV_TYPE, MAV_RESULT, etc.) | ~5,500 |
+| `MAVLinkMessageType.h` | `mavlink_message_t`, `mavlink_channel_t`, base types | ~2,700 |
+| `QGCMAVLinkTypes.h` | `FirmwareClass_t`, `VehicleClass_t`, `maxRcChannels` | ~50 |
+| `VehicleTypes.h` | `MavCmdResultFailureCode_t`, `RequestMessageResultHandlerFailureCode_t` | ~30 |
+| `QGCMAVLink.h` | All of the above combined | ~8,300 |
+| `MAVLinkLib.h` | Full MAVLink with all 387 message pack/unpack headers | ~180,000 |
+
+## Rules
+
+1. **Never include `MAVLinkLib.h` in a `.h` file** unless the header uses specific MAVLink message struct types in its declarations (e.g., `mavlink_command_long_t`, `mavlink_command_ack_t`). Move message struct usage to `.cc` files when possible.
+
+2. **Never include `Vehicle.h` just for type aliases.** Use `VehicleTypes.h` + `class Vehicle;` forward declaration instead, when only `MavCmdResultFailureCode_t` or `RequestMessageResultHandlerFailureCode_t` are needed.
+
+3. **Pick the lightest include that satisfies the header's needs:**
+   - Only enum constants? → `MAVLinkEnums.h`
+   - `mavlink_message_t` in signatures? → `MAVLinkMessageType.h`
+   - Both enums and message type? → `MAVLinkEnums.h` + `MAVLinkMessageType.h` (still lighter than `QGCMAVLink.h`)
+   - `FirmwareClass_t` / `VehicleClass_t`? → `QGCMAVLinkTypes.h`
+
+4. **Headers must be self-contained.** Every type used in a header's declarations must be provided by an explicit `#include`, not by the precompiled header (PCH). The PCH provides `MAVLinkLib.h` for `.cc` files, but moc processes headers independently.
+
+5. **`MAVLinkLib.h` is fine in `.cc` files** — it's provided by the PCH anyway. Only header includes affect moc parse time.

cmake/GenerateMAVLinkEnums.py

@@ -0,0 +1,116 @@
+#!/usr/bin/env python3
+"""Extract enum definitions from MAVLink dialect headers into a standalone header.
+
+Usage: python3 GenerateMAVLinkEnums.py <mavlink_include_dir> <output_file>
+
+Example:
+    python3 GenerateMAVLinkEnums.py build/_deps/mavlink-build/include/mavlink build/MAVLinkEnums.h
+"""
+import os
+import sys
+
+def extract_enums(dialect_header_path):
+    """Extract text between '// ENUM DEFINITIONS' and '// MESSAGE DEFINITIONS' markers."""
+    try:
+        with open(dialect_header_path, 'r') as f:
+            lines = f.readlines()
+    except FileNotFoundError:
+        return ""
+
+    in_enums = False
+    enum_lines = []
+    for line in lines:
+        if '// ENUM DEFINITIONS' in line:
+            in_enums = True
+            continue
+        if '// MESSAGE DEFINITIONS' in line:
+            break
+        if in_enums:
+            enum_lines.append(line)
+    return ''.join(enum_lines)
+
+
+def find_dialects(mavlink_dir):
+    """Find all dialect directories that contain a dialect header."""
+    dialects = []
+    for entry in sorted(os.listdir(mavlink_dir)):
+        dialect_dir = os.path.join(mavlink_dir, entry)
+        dialect_header = os.path.join(dialect_dir, f"{entry}.h")
+        if os.path.isdir(dialect_dir) and os.path.isfile(dialect_header):
+            dialects.append((entry, dialect_header))
+    return dialects
+
+
+def main():
+    if len(sys.argv) != 3:
+        print(f"Usage: {sys.argv[0]} <mavlink_include_dir> <output_file>", file=sys.stderr)
+        sys.exit(1)
+
+    mavlink_dir = sys.argv[1]
+    output_file = sys.argv[2]
+
+    if not os.path.isdir(mavlink_dir):
+        print(f"Error: {mavlink_dir} is not a directory", file=sys.stderr)
+        sys.exit(1)
+
+    dialects = find_dialects(mavlink_dir)
+    if not dialects:
+        print(f"Error: no dialect headers found in {mavlink_dir}", file=sys.stderr)
+        sys.exit(1)
+
+    # Build output
+    parts = []
+    parts.append("""\
+#pragma once
+
+/// @file MAVLinkEnums.h
+/// @brief MAVLink enum definitions only - no message pack/unpack code.
+///
+/// AUTO-GENERATED from MAVLink dialect headers during the build.
+/// Do not edit manually. Regenerate via cmake/GenerateMAVLinkEnums.py.
+///
+/// This header provides all MAVLink enum typedefs (~3,700 lines) without
+/// the ~177,000 lines of message pack/encode/decode functions.
+/// Use this in headers that need MAVLink enum types (MAV_CMD, MAV_TYPE, etc.)
+/// but don't need message struct definitions.
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+""")
+
+    for name, path in dialects:
+        enums = extract_enums(path)
+        if enums.strip():
+            parts.append(f"\n// ---- enums from {name}/{name}.h ----\n")
+            parts.append(enums)
+
+    parts.append("""
+#ifdef __cplusplus
+}
+#endif
+""")
+
+    output = ''.join(parts)
+
+    # Ensure output directory exists
+    os.makedirs(os.path.dirname(os.path.abspath(output_file)), exist_ok=True)
+
+    # Only write if content changed (avoid unnecessary rebuilds)
+    if os.path.isfile(output_file):
+        with open(output_file, 'r') as f:
+            if f.read() == output:
+                print(f"MAVLinkEnums.h is up to date ({output_file})")
+                return
+
+    with open(output_file, 'w') as f:
+        f.write(output)
+
+    # Count enums
+    enum_count = output.count('typedef enum')
+    line_count = output.count('\n')
+    print(f"Generated {output_file}: {line_count} lines, {enum_count} enums from {len(dialects)} dialects")
+
+
+if __name__ == '__main__':
+    main()

src/ADSB/ADSB.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include "MAVLinkLib.h"
+#include "MAVLinkEnums.h"
 
 #include <QtCore/QMetaType>
 #include <QtPositioning/QGeoCoordinate>

src/ADSB/ADSBVehicleManager.cc

@@ -1,4 +1,5 @@
 #include "ADSBVehicleManager.h"
+#include "MAVLinkLib.h"
 #include "QGCApplication.h"
 #include "SettingsManager.h"
 #include "ADSBVehicleManagerSettings.h"

src/ADSB/ADSBVehicleManager.h

@@ -4,7 +4,7 @@
 #include <QtCore/QObject>
 
 #include "ADSB.h"
-#include "MAVLinkLib.h"
+#include "MAVLinkMessageType.h"
 
 Q_DECLARE_LOGGING_CATEGORY(ADSBVehicleManagerLog)
 

src/API/QGCCorePlugin.cc

@@ -3,6 +3,7 @@
 #include "AppSettings.h"
 #include "MavlinkSettings.h"
 #include "FactMetaData.h"
+#include "QGCMAVLink.h"
 #ifdef QGC_GST_STREAMING
 #include "GStreamer.h"
 #endif

src/AnalyzeView/MAVLinkInspector/MAVLinkInspectorController.h

@@ -5,7 +5,7 @@
 #include <QtCore/QString>
 #include <QtQmlIntegration/QtQmlIntegration>
 
-#include "MAVLinkLib.h"
+#include "MAVLinkMessageType.h"
 
 Q_DECLARE_LOGGING_CATEGORY(MAVLinkInspectorControllerLog)
 

src/AnalyzeView/MAVLinkInspector/MAVLinkMessage.cc

@@ -1,4 +1,5 @@
 #include "MAVLinkMessage.h"
+#include "MAVLinkLib.h"
 #include "MAVLinkMessageField.h"
 #include "QGCLoggingCategory.h"
 #include "QmlObjectListModel.h"

src/AnalyzeView/MAVLinkInspector/MAVLinkMessage.h

@@ -5,7 +5,7 @@
 #include <QtCore/QLoggingCategory>
 #include <QtQmlIntegration/QtQmlIntegration>
 
-#include "MAVLinkLib.h"
+#include "MAVLinkMessageType.h"
 
 class QmlObjectListModel;
 

src/AutoPilotPlugins/APM/APMFlightModesComponentController.h

@@ -5,7 +5,7 @@
 #include <QtQmlIntegration/QtQmlIntegration>
 
 #include "FactPanelController.h"
-#include "QGCMAVLink.h"
+#include "QGCMAVLinkTypes.h"
 
 /// MVC Controller for FlightModesComponent.qml.
 class APMFlightModesComponentController : public FactPanelController
@@ -57,7 +57,7 @@ private slots:
     Fact *_superSimpleModeFact = nullptr;
     const bool _simpleModesSupported = false;
     int _activeFlightMode = 0;
-    int _channelCount = QGCMAVLink::maxRcChannels;
+    int _channelCount = QGCMAVLinkTypes::maxRcChannels;
     int _simpleMode = SimpleModeStandard;
     QString _modeChannelParam;
     QString _modeParamPrefix;

src/AutoPilotPlugins/Common/ESP8266ComponentController.h

@@ -5,7 +5,7 @@
 #include <QtQmlIntegration/QtQmlIntegration>
 
 #include "FactPanelController.h"
-#include "MAVLinkLib.h"
+#include "MAVLinkEnums.h"
 
 Q_DECLARE_LOGGING_CATEGORY(ESP8266ComponentControllerLog)
 

src/AutoPilotPlugins/PX4/ActuatorComponent.cc

@@ -2,6 +2,7 @@
 #include "QGCApplication.h"
 #include "GeometryImage.h"
 #include "Actuators/Actuators.h"
+#include "Vehicle.h"
 
 #include <QtQml/QQmlApplicationEngine>
 

src/AutoPilotPlugins/PX4/PX4SimpleFlightModesController.h

@@ -4,7 +4,6 @@
 #include <QtQmlIntegration/QtQmlIntegration>
 
 #include "FactPanelController.h"
-#include "QGCMAVLink.h"
 
 /// MVC Controller for PX4SimpleFlightModes.qml
 class PX4SimpleFlightModesController : public FactPanelController

src/Camera/QGCCameraManager.cc

@@ -3,11 +3,13 @@
 #include "FirmwarePlugin.h"
 #include "Joystick.h"
 #include "JoystickManager.h"
+#include "MAVLinkLib.h"
 #include "MavlinkCameraControlInterface.h"
 #include "MultiVehicleManager.h"
 #include "QGCLoggingCategory.h"
 #include "QGCVideoStreamInfo.h"
 #include "SimulatedCameraControl.h"
+#include "Vehicle.h"
 
 #include <cmath>
 #include "GimbalControllerSettings.h"

src/Camera/QGCCameraManager.h

@@ -9,9 +9,10 @@
 #include <QtCore/QVariantList>
 #include <QtQmlIntegration/QtQmlIntegration>
 
-#include "MAVLinkLib.h"
+#include "MAVLinkMessageType.h"
 #include "QmlObjectListModel.h"
-#include "Vehicle.h"
+
+class Vehicle;
 
 Q_DECLARE_LOGGING_CATEGORY(CameraManagerLog)
 
@@ -54,7 +55,7 @@ class QGCCameraManager : public QObject
         int retryCount = 0;
         QElapsedTimer lastHeartbeat;
         QTimer backoffTimer;
-        QPointer<Vehicle> vehicle;
+        Vehicle* vehicle;           ///< Raw pointer is safe: CameraStruct is owned by QGCCameraManager which is a child of Vehicle
         QPointer<QGCCameraManager> manager;
 
     private:
@@ -128,7 +129,7 @@ private slots:
     void _addCameraControlToLists(MavlinkCameraControlInterface* cameraControl);
     void _handleCameraFovStatus(const mavlink_message_t& message);
 
-    QPointer<Vehicle> _vehicle;
+    Vehicle* _vehicle;              ///< Raw pointer is safe: QGCCameraManager is a QObject child of Vehicle, so Vehicle always outlives us
     QPointer<SimulatedCameraControl> _simulatedCameraControl;
     QPointer<Joystick> _activeJoystick;
     bool _vehicleReadyState = false;

src/Comms/MAVLinkProtocol.h

@@ -6,7 +6,8 @@
 #include <QtCore/QString>
 
 #include "LinkInterface.h"
-#include "MAVLinkLib.h"
+#include "MAVLinkEnums.h"
+#include "MAVLinkMessageType.h"
 
 class QFile;
 

src/Comms/MockLink/MockConfiguration.h

@@ -3,7 +3,7 @@
 #include "LinkConfiguration.h"
 
 #include <QtCore/QLoggingCategory>
-#include "MAVLinkLib.h"
+#include "MAVLinkEnums.h"
 
 Q_DECLARE_LOGGING_CATEGORY(MockConfigurationLog)
 

src/FactSystem/FactGroup.h

@@ -8,7 +8,7 @@
 #include <QtQmlIntegration/QtQmlIntegration>
 
 #include "Fact.h"
-#include "MAVLinkLib.h"
+#include "MAVLinkMessageType.h"
 
 class Vehicle;
 

src/FactSystem/FactGroupListModel.h

@@ -1,7 +1,7 @@
 #pragma once
 
 #include "QmlObjectListModel.h"
-#include "QGCMAVLink.h"
+#include "MAVLinkMessageType.h"
 #include "FactGroupWithId.h"
 
 #include <QList>

src/FactSystem/ParameterManager.h

@@ -10,7 +10,8 @@
 
 #include "Fact.h"
 #include "FactMetaData.h"
-#include "MAVLinkLib.h"
+#include "MAVLinkEnums.h"
+#include "MAVLinkMessageType.h"
 
 Q_DECLARE_LOGGING_CATEGORY(ParameterManagerLog)
 Q_DECLARE_LOGGING_CATEGORY(ParameterManagerVerbose1Log)

src/FirmwarePlugin/APM/APMParameterMetaData.h

@@ -5,7 +5,7 @@
 #include <QtCore/QObject>
 #include <QtCore/QXmlStreamReader>
 
-#include "MAVLinkLib.h"
+#include "MAVLinkEnums.h"
 #include "FactMetaData.h"
 
 Q_DECLARE_LOGGING_CATEGORY(APMParameterMetaDataLog)

src/FirmwarePlugin/FirmwarePlugin.cc

@@ -7,6 +7,7 @@
 #include "QGCCameraManager.h"
 #include "QGCFileDownload.h"
 #include "QGCLoggingCategory.h"
+#include "Vehicle.h"
 #include "VehicleCameraControl.h"
 #include "VehicleComponent.h"