# ScenicNew
The `scenic.new` mix task, which generates out a starter application for you.
This is the easiest way to set up a new Scenic project.
## Erlang/Elixir versions
Please note, it currently needs OTP 21 and Elixir 1.7. If you have trouble
compiling, please check that you are running those versions first.
## Install Prerequisites
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](https://elixir-lang.org/install.html).
### Installing on MacOS
The easiest way to install on MacOS is to use Homebrew. Just run the following
in a terminal:
```bash
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 16
The easiest way to install on Ubuntu is to use apt-get. Just run the following:
```bash
sudo apt-get update
sudo apt-get install pkgconf libglfw3 libglfw3-dev libglew1.13 libglew-dev
```
Once these components have been installed, you should be able to build the
`scenic_driver_glfw` driver.
### Installing on Ubuntu 18
The easiest way to install on Ubuntu is to use apt-get. Just run the following:
```bash
sudo apt-get update
sudo 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`
```bash
mix archive.install hex scenic_new
```
To build and run scenic applications, you will also need to install a few
dependencies. See the [Getting
started](https://hexdocs.pm/scenic/getting_started.html#install-dependencies)
for more information.
### Build and install locally
To build and install this archive locally ensure any previous archive versions
are removed:
```bash
mix archive.uninstall scenic_new
```
Then run:
```bash
cd scenic_new
MIX_ENV=prod mix do archive.build, archive.install
```
## Build the Starter Application
First, navigate the command-line to the directory where you want to create your
new Scenic application. Then run the following commands: (change `my_app` to
the name of your application)
```bash
mix scenic.new my_app
cd my_app
mix do deps.get, scenic.run
```
## Running and Debugging
Once the application and its dependencies are set up, there are two main ways
to run it.
If you want to run your application under `IEx` so that you can debug it,
simply run
```bash
iex -S mix
```
This works just like any other Elixir application.
If you want to run your application outside of `IEx`, you should start it like
this:
```bash
mix scenic.run
```
## The Starter Application
The starter application 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 application 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 supervision tree restarts the scene. It also shows how to receive events from components.
Component | Description
--- | ---
Nav | The navigation 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 guides describing the overall Scenic structure. This is
in the documentation for Scenic itself
