cubs2_rviz
==========

Custom RViz2 panel plugins for Cubs2 aircraft simulation and control.

Plugins
-------

Video Panel
^^^^^^^^^^^

Low-latency GStreamer video streaming panel for drone camera visualization.

**Features:**

* Direct GStreamer rendering (no ROS 2 image topic overhead)
* Multiple input sources: USB cameras, RTSP, UDP (H.264/MJPEG), test patterns
* Predefined source templates for common use cases
* Custom GStreamer pipeline support
* Real-time video display with automatic aspect ratio

**Usage:**

1. In RViz: ``Panels`` → ``Add New Panel`` → ``cubs2::VideoPanel``
2. Select a predefined source or enter custom GStreamer URI
3. Click "Connect"

**Predefined Sources:**

* **Test Pattern**: SMPTE color bars for testing
* **USB Camera**: V4L2 camera on ``/dev/video0``
* **RTSP Stream**: Network camera stream
* **UDP Stream (H.264)**: H.264 encoded UDP on port 5600
* **UDP Stream (MJPEG)**: MJPEG encoded UDP on port 5600

**Custom Pipeline Examples:**

.. code-block:: bash

   # Different USB camera device
   v4l2src device=/dev/video1 ! video/x-raw,width=1280,height=720,framerate=30/1

   # RTSP with authentication
   rtspsrc location=rtsp://username:password@192.168.1.100:8554/video latency=0 ! decodebin

   # Custom UDP port
   udpsrc port=5000 ! application/x-rtp,encoding-name=H264 ! rtph264depay ! avdec_h264

   # File playback
   filesrc location=/path/to/video.mp4 ! decodebin

**Drone Camera Setup:**

On companion computer (Raspberry Pi):

.. code-block:: bash

   # Stream USB camera via UDP H.264
   gst-launch-1.0 v4l2src device=/dev/video0 ! \
     video/x-raw,width=640,height=480,framerate=30/1 ! \
     x264enc tune=zerolatency bitrate=2000 speed-preset=superfast ! \
     rtph264pay ! udpsink host=<ground-station-ip> port=5600

In RViz Video Panel, select "UDP Stream (H.264)" and click "Connect".

**Required Dependencies:**

.. code-block:: bash

   sudo apt-get install \
     gstreamer1.0-plugins-base \
     gstreamer1.0-plugins-good \
     gstreamer1.0-plugins-bad \
     gstreamer1.0-plugins-ugly \
     gstreamer1.0-libav

**Troubleshooting:**

* Check camera: ``ls /dev/video*``
* Test pipeline: ``gst-launch-1.0 videotestsrc ! autovideosink``
* View RViz terminal for detailed GStreamer errors
* For low latency: use UDP over RTSP, reduce resolution/framerate for limited bandwidth

**Performance Tips:**

* Start with 640x480 @ 30fps
* Use H.264 for network streams
* Set ``tune=zerolatency`` on encoder
* Prefer wired Ethernet for reliability

Joy Panel
^^^^^^^^^

Virtual joystick for manual aircraft control.

**Features:**

* 2D joystick widget (aileron/elevator)
* Throttle and rudder sliders
* Trim controls for aileron and elevator
* Enable/disable checkbox to prevent conflicts with gamepad
* Spring-back to center when released

**Topics:**

* Publishes: ``/control`` (cubs2_msgs/AircraftControl)
* Subscribes: ``/control`` (to display external control when disabled)

Sim Panel
^^^^^^^^^

Simulation control and configuration.

**Features:**

* Reset simulation button
* Pause/resume checkbox
* Simulation speed selector (0.25x to 100x)
* Time step selector (0.001s to 0.1s)
* Camera position publishing for advanced visualization

**Topics:**

* Publishes: ``/reset``, ``/pause``, ``/set_speed``, ``/set_dt``
* Subscribes: ``/sat/paused`` (to sync pause state)

HUD Panel
^^^^^^^^^

Heads-up display for flight telemetry.

**Features:**

* Artificial horizon (pitch/roll)
* Roll indicator (arc with angle markers)
* Altitude display
* Airspeed display
* Real-time attitude visualization

**Topics:**

* Subscribes: ``/sportcub/pose``, ``/sportcub/velocity``

Usage
-----

Load Panels in RViz
^^^^^^^^^^^^^^^^^^^

1. Launch RViz: ``ros2 launch cubs2_bringup viz.xml``
2. In RViz menu: ``Panels`` → ``Add New Panel``
3. Select from:
   
   * ``cubs2::VideoPanel``
   * ``cubs2/JoyPanel``
   * ``cubs2/SimPanel``
   * ``cubs2/HUDPanel``

Pre-configured RViz Config
^^^^^^^^^^^^^^^^^^^^^^^^^^^

Panels are automatically loaded with:

.. code-block:: bash

   ros2 launch cubs2_bringup viz.xml

Development
-----------

Building
^^^^^^^^

.. code-block:: bash

   colcon build --packages-select cubs2_rviz

Plugin Architecture
^^^^^^^^^^^^^^^^^^^

Plugins use the RViz2 ``rviz_common::Panel`` API with Qt5 widgets.

**Key Components:**

* ``include/cubs2_rviz/*.hpp`` - Header files
* ``src/rviz/*.cpp`` - Implementation
* ``plugin_description.xml`` - Plugin registration
* ``config/cubs2.rviz`` - Pre-configured layout

Adding a New Panel
^^^^^^^^^^^^^^^^^^

1. Create header in ``include/cubs2_rviz/my_panel.hpp``:

.. code-block:: cpp

   #include <rviz_common/panel.hpp>

   namespace cubs2 {
   class MyPanel : public rviz_common::Panel {
     Q_OBJECT
   public:
     MyPanel(QWidget* parent = nullptr);
   };
   }

2. Implement in ``src/rviz/my_panel.cpp``
3. Export with ``PLUGINLIB_EXPORT_CLASS(cubs2::MyPanel, rviz_common::Panel)``
4. Register in ``plugin_description.xml``

Qt Integration
^^^^^^^^^^^^^^

Panels use Qt5 for GUI:

* **Widgets**: QSlider, QPushButton, QCheckBox, QLabel
* **Layouts**: QVBoxLayout, QHBoxLayout
* **Custom painting**: QPainter for HUD graphics
* **Timers**: QTimer for periodic updates

Dependencies
------------

**ROS2 Packages:**

* rclcpp
* rviz_common
* pluginlib

**Cubs2 Packages:**

* cubs2_msgs
* cubs2_description
* racecourse_description

**System:**

* Qt5 (qtbase5-dev)
* GStreamer 1.0 (libgstreamer1.0-dev, libgstreamer-plugins-base1.0-dev)
* geometry_msgs
* std_msgs
* sensor_msgs

Testing
-------

.. code-block:: bash

   # Lint and style checks
   colcon test --packages-select cubs2_rviz

   # Test video stream (for Video Panel testing)
   ./scripts/test_video_stream.sh --pattern ball