/rpi_lcars

Star Trek LCARS interface for Raspberry Pi using Pygame

Primary LanguagePythonMIT LicenseMIT

RaspberryPi LCARS Interface

Star Trek LCARS interface for Raspberry Pi using Pygame.

The code is an example of implementing a custom MovieOS-style interface for your RaspberryPi projects that include the RaspberryPi touch screen (e.g. home automation control panel). The LCARS assets can be replaced with assets from any other style of user interface (e.g. from games, cartoons, or TV series).

screenshot 1

(Click screenshot for a video)

Global Config

  • UI_PLACEMENT_MODE - if set to True, allows you to long-press any widget (except background items) and then drag them to any location. When you release the widget, it's new top and left co-ordinates are printed in the console, which you can use in your code to place the widget there.
  • DEV_MODE - if set to True, will show the mouse cursor, for example. The mouse cursor is useful during development (on a non-touch screen).

Usage

  • The starting point for modifying this interface to your needs is the initial Screen that is loaded, which is ScreenAuthorize. The Screens are defined in the screens folder.
  • Screens extend the LcarsScreen class and define a setup() method, and optionally the handleEvents() and update() methods.
  • The setup() method initializes the widgets to display. See lcars_widgets.py for some of the implemented widgets.
  • The handleEvents() method is used to respond to clicks. If this method returns True, the event is "consumed", otherwise other widgets get a chance to act on the event.
  • The update() method is called once per frame, allowing the Screen to update how it is drawn. Code in here needs to be highly optimized. This method is called after the widgets are drawn, but there is a pre_update() method you can override to draw before the widgets get drawn.
  • The method loadScreen() can be called to open a new Screen. There is no backstack, so you will have to manage the Screen flows manually.

Installation

  • Download or Git clone this repository into a local folder
  • Run the setup.sh script to install the needed dependencies, OR if you have pip, run pip install -r requirements.txt

Launching

  • You can launch the interface from inside an X desktop session by opening a terminal and running python lcars.py from inside the app folder.
  • To launch the interface from the command line, run the run.sh script in the project root. Note that you will need to have xinit installed (sudo apt-get install xinit). While you can run it without X, the touch points will be mis-aligned, and so is not feasible.
  • You can launch the interface on bootup by adding the following to the /etc/rc.local file:
cd /home/pi/rpi_lcars/app
sudo -u pi xinit /usr/bin/python lcars.py

The above assumes you want to run the interface from the /home/pi/rpi_lcars folder as the pi user. To run as root, simply omit the sudo -u pi bit.

Notes

  • Although not implemented in the demo, an interpolator is provided to allow for animations. To see how this can be used, see the LcarsMoveToMouse widget, which smoothly follows screen touches/mouse clicks.
  • The applyColour() method is used to take an image asset of a uniform colour (e.g. white) and change its colour to any other colour. This is how buttons of various colours are created from one asset. However, currently this is a very simple implementation which results in aliasing artifacts, which is why the buttons look aliased. The advantage of this method is that it is trivial to use it to add highlighting of touches on buttons and keep the number of assets required to a minimum.
  • If you are using the Waveshare 5" or 7" touch screen (or similar), then you can use the sample boot/config.txt to get the screen running at the correct resolution, and install a user-space touch driver, like this one

Credits