u3d/dependencies: add command to install Linux dependencies

README.md

@@ -43,6 +43,8 @@ The prettifyer is on by default but can be turned off to get Unity3d's raw outpu
 
   [Information on how `prettify` works](https://github.com/DragonBox/u3d/blob/master/LOG_RULES.md)
 
+* `u3d dependencies`: [Linux] Install dependencies that Unity don't install by default on Linux.
+
 ## Installation
 
 ```shell

lib/u3d/commands.rb

@@ -129,6 +129,15 @@ def install(args: [], options: {})
         Installer.install_modules(files, definition.version, installation_path: options[:installation_path])
       end
 
+      def install_dependencies
+        unless Helper.linux?
+          UI.important 'u3d dependencies is Linux-only, and not needed on other OS'
+          return
+        end
+
+        LinuxDependencies.install
+      end
+
       def run(options: {}, run_args: [])
         version = options[:unity_version]
 

lib/u3d/commands_generator.rb

@@ -148,6 +148,22 @@ def run
         end
       end
 
+      command :dependencies do |c|
+        c.syntax = 'u3d dependencies'
+        c.summary = 'Installs Unity dependencies. [Linux only]'
+        c.description = %(
+#{c.summary}
+
+Regarding the package manager: if dpkg is installed, u3d uses apt-get else if rpm is installed yum is used. If none of them is insalled, fails.
+
+Regarding the dependencies themselves: only dependencies for the editor are installed. WebGL, Android and Tizen require others that you will have to install manually.
+More on that: https://forum.unity3d.com/threads/unity-on-linux-release-notes-and-known-issues.350256/
+                  )
+        c.action do |_args, _options|
+          Commands.install_dependencies
+        end
+      end
+
       command :credentials do |c|
         c.syntax = "u3d credentials <#{Commands.credentials_actions.join(' | ')}>"
         c.description = 'Manages keychain credentials so u3d remembers them. [OSX only]'

lib/u3d/installer.rb

@@ -279,4 +279,63 @@ def install_exe(file_path, installation_path: nil, info: {})
       end
     end
   end
+
+  class LinuxDependencies
+    # see https://forum.unity3d.com/threads/unity-on-linux-release-notes-and-known-issues.350256/
+    DEPENDENCIES = [
+      'gconf-service',
+      'lib32gcc1',
+      'lib32stdc++6',
+      'libasound2',
+      'libc6',
+      'libc6-i386',
+      'libcairo2',
+      'libcap2',
+      'libcups2',
+      'libdbus-1-3',
+      'libexpat1',
+      'libfontconfig1',
+      'libfreetype6',
+      'libgcc1',
+      'libgconf-2-4',
+      'libgdk-pixbuf2.0-0',
+      'libgl1-mesa-glx',
+      'libglib2.0-0',
+      'libglu1-mesa',
+      'libgtk2.0-0',
+      'libnspr4',
+      'libnss3',
+      'libpango1.0-0',
+      'libstdc++6',
+      'libx11-6',
+      'libxcomposite1',
+      'libxcursor1',
+      'libxdamage1',
+      'libxext6',
+      'libxfixes3',
+      'libxi6',
+      'libxrandr2',
+      'libxrender1',
+      'libxtst6',
+      'zlib1g',
+      'debconf',
+      'npm',
+      'libpq5' # missing from original list
+    ].freeze
+
+    def self.install
+      if `which dpkg` != ''
+        prefix = 'apt-get -y install'
+      elsif `which rpm` != ''
+        prefix = 'yum -y install'
+      else
+        raise 'Cannot install dependencies on your Linux distribution'
+      end
+
+      if UI.interactive?
+        return unless UI.confirm "Install dependencies? (#{DEPENDENCIES.length} dependency(ies) to install)"
+      end
+      U3dCore::CommandExecutor.execute(command: "#{prefix} #{DEPENDENCIES.join(' ')}", admin: true)
+    end
+  end
 end