Getting Started

This guide will walk you through installing the OpenGL related dependencies, then building your first Scenic application.

Install Dependencies

The design of Scenic goes to great lengths to minimize its dependencies to just the minimum. Namely, it needs Erlang/Elixir and OpenGL.

Rendering your application into a window on your local computer (MacOS, Ubuntu and others) is done by the scenic_driver_glfw driver. It uses the GLFW and GLEW libraries to connect to OpenGL.

The instructions below assume you have already installed Elixir/Erlang. If you need to install Elixir/Erlang there are instructions on the elixir-lang website.

Installing on MacOS

The easiest way to install on MacOS is to use Homebrew. Just run the following in a terminal:

brew update
brew install glfw3 glew pkg-config

Once these components have been installed, you should be able to build the scenic_driver_glfw driver.

Installing on Ubuntu

The easiest way to install on Ubuntu is to use apt-get. Just run the following:

apt-get update
apt-get install pkgconf libglfw3 libglfw3-dev libglew2.0 libglew-dev

Once these components have been installed, you should be able to build the scenic_driver_glfw driver.

Install scenic.new

The Scenic Archive is the home of the scenic.new mix task, which lays out a starter application for you. This is the easiest way to set up a new Scenic project.

Install the Scenic Archive like this

mix archive.install hex scenic_new

Build the Starter App

First, navigate the command-line to the directory where you want to create your new Scenic app. Then run the following commands: (change my_app to the name of your app…)

mix scenic.new my_app
cd my_app
mix do deps.get, scenic.run

Running and Debugging

Once the app and its dependencies are set up, there are two main ways to run it.

If you want to run your app under IEx so that you can debug it, simply run

iex -S mix

This works just like any other Elixir application.

If you want to run your app outside of iex, you should start it like this:

mix scenic.run

The Starter App

The starter app created by the generator above shows the basics of building a Scenic application. It has four scenes, two components, and a simulated sensor.

Scene	Description
Splash	The Splash scene is configured to run when the app is started in the config/config.exs file. It runs a simple animation, then transitions to the Sensor scene. It also shows how intercept basic user input to exit the scene early.
Sensor	The Sensor scene depicts a simulated temperature sensor. The sensor is always running and updates it’s data through the Scenic.SensorPubSub server.
Primitives	The Primitives scenes displays an overview of the basic primitive types and some of the styles that can be applied to them.
Components	The Components scene shows the basic components that come with Scenic. The crash button will cause a match error that will crash the scene, showing how the supervison tree restarts the scene. It also shows how to receive events from components.

Component	Description
Nav	The nav bar at the top of the main scenes shows how to navigate between scenes and how to construct a simple component and pass a parameter to it. Note that it references a clock, creating a nested component. The clock is positioned by dynamically querying the width of the ViewPort
Notes	The notes section at the bottom of each scene is very simple and also shows passing in custom data from the parent.

The simulated temperature sensor doesn’t collect any actual data, but does show how you would set up a real sensor and publish data from it into the Scenic.SensorPubSub service.

What to read next

Next, you should read about the structure of a scene. This will explain the parts of a scene, how to send and receive messages and how to push the graph to the ViewPort.