% Part   : Concepts

% Chapter: Corporate Identity

% ------------------------------------------------------------

% $Id: themes.tex 6207 2010-08-05 13:11:13Z al $

% ------------------------------------------------------------

\section{Themes}

\hypertarget{sec:Concepts:Identity:Themes}{}

\label{sec:Concepts:Identity:Themes}

\begin{description}

\item[framework:] trunk/Identity/Themes/

\end{description}

\noindent Here is where themes are produced.  In the above framework

location, themes are organized in ``Models'' ---to store common

information--- and ``Motifs''---to store unique information.  At

rendering time, both motifs and models are combined to produce the

final CentOS themes. CentOS themes can be tagged as ``default'' or

``alternative''. 

CentOS themes are maintained by CentOS community. 

% ------------------------------------------------------------

\section{CentOS Default Theme}

\hypertarget{sec:Concepts:Identity:Themes:Default}{}

\label{sec:Concepts:Identity:Themes:Default}

The CentOS default theme is used in all visual manifestations of

CentOS Project's corporate visual identity (e.g., distributions, web

sites, promotion, etc.).

Changing CentOS default theme is not very convenient because that

affects the ``recognition'' of CentOS Project.  Nevertheless, we are

interested on seeing your art work propositions.  Specially if your

art work is an improvement to the base idea behind CentOS default theme

(\textbf{Modern}, squares and circles flowing up.).

If you are not happy with CentOS default theme, you can look inside

CentOS alternative themes and download the one you are interested in.

If you are not happy with any of the CentOS alternative themes

available, then go and design your own CentOS alternative theme as

described in ``\hyperlink{sec:Concepts:Identity:Themes:Motifs}{Theme

Motifs}'' (\autoref{sec:Concepts:Identity:Themes:Motifs}).

% ------------------------------------------------------------

\section{CentOS Alternative Themes}

\hypertarget{sec:Concepts:Identity:Themes:Alternative}{}

\label{sec:Concepts:Identity:Themes:Alternative}

CentOS alternative themes exist for people how want to use a different

visual style on their installations of CentOS distribution. As the

visual style is needed for a system already installed components like

Anaconda are not required inside alternative themes. Inside

alternative themes you find post-installation visual style only (i.e.

Backgrounds, Display Managers, Grub, etc.).  CentOS alternative themes

are maintained by CentOS Community.

% ------------------------------------------------------------

\section{Theme Transition}

\hypertarget{sec:Concepts:Identity:Themes:Transition}{}

\label{sec:Concepts:Identity:Themes:Transition}

Theme transition is the action of moving a theme from alternative to

default.  This transition begins when an alternative theme gets

popular enough inside CentOS Comminity, and both CentOS Administrators

and CentOS Comunity Members want to extend it to all CentOS Visual

Manifestations. 

Once the popular alternative theme has been extended through all

CentOS visual manifestations, the alternative theme implementation

phase starts. The alternative theme implementation phase is where

default theme art work is replaced with alternative theme ones. After

the implementation phase, the previous default theme is tagged as

alternative and the implemented alternative as default.

Theme Transition has a huge impact in CentOS Corporate Visual

Identity, it should be done only if absolutly necessary. Generally, it

is better to improve the current default theme, based on its concept,

than create a completly new one. 

% ------------------------------------------------------------

\section{Theme Models}

\hypertarget{sec:Concepts:Identity:Themes:Models}{}

\label{sec:Concepts:Identity:Themes:Models}

\begin{description}

\item[framework:] trunk/Identity/Themes/Models/

\end{description}

\noindent Here is where theme models are stored.  Theme models let you

modeling characteristics (e.g., dimensions, translation markers,

position of each element on the display area, etc.) common to all

themes.  Theme models let you reduce the time needed when propagating

artistic motifs to different visual manifestations.

\begin{figure}[!hbp]

\hrulefill

\begin{verbatim}

trunk/Identity/Themes/

|-- Models

|   |-- Default             <-- theme's model name.

|   |   |-- Distro

|   |   |   |-- Anaconda

|   |   |   |   |-- Header

|   |   |   |   |-- Progress

|   |   |   |   |-- Prompt

|   |   |   |   `-- Splash

|   |   |   `-- BootUp

|   |   |       |-- Firstboot

|   |   |       |-- GDM

|   |   |       |-- GRUB

|   |   |       |-- GSplash

|   |   |       |-- KDM

|   |   |       |-- KSplash  

|   |   |       |-- RHGB

|   |   |       `-- Plymouth

|   |   |-- Promo

|   |   |-- Web

|   |-- Alternative        <-- theme's model name.

|   |   |-- Distro

|   |   |   `-- BootUp

|   |   |       |-- Firstboot

|   |   |       |-- GDM

|   |   |       |-- GRUB

|   |   |       |-- GSplash

|   |   |       |-- KDM

|   |   |       |-- KSplash  

|   |   |       |-- RHGB

|   |   |       `-- Plymouth

|   |-- ... more theme models.

\end{verbatim}

\hrulefill

\caption{Theme models structure.%

   \label{fig:Concepts:Identity:Themes:Models}}

\end{figure}

Theme models serves as a central pool of design templates for themes

to use. This way you can produce themes with different artistic motifs

but same characteristics.

Inside the framework location above, you find theme models organized

by name. You can add your own theme models to the structure by adding

a directory to the list. By default you have the following

ready-to-use theme models:

\begin{itemize}

\item \textbf{Default:} Stores the theme model used to produce

``\hyperlink{sec:Concepts:Identity:Themes:Default}{CentOS

Default Theme}''

(\autoref{sec:Concepts:Identity:Themes:Default}). 

\item \textbf{Alternative:} Stores the theme model used to produce

``\hyperlink{sec:Concepts:Identity:Themes:Alternative}{CentOS

Alternative Themes}''

(\autoref{sec:Concepts:Identity:Themes:Alternative}). 

\end{itemize}

\begin{figure}

\begin{center}

\fbox{\includegraphics[width=0.8\textwidth]{%

   /home/centos/artwork/trunk/Identity/Models/Img/en/Corporate/common-design-model-fig1.pdf}}

\end{center}

\caption{Anaconda theme model producing three different visual

styles.}

\end{figure}

\begin{figure}

\begin{center}

\fbox{\includegraphics[width=0.8\textwidth]{%

   /home/centos/artwork/trunk/Identity/Models/Img/en/Corporate/common-design-model-fig2.pdf}}

\end{center}

\caption{Firstboot theme model producing three different visual

styles.}

\end{figure}

% ------------------------------------------------------------

\section{Theme Motifs}

\hypertarget{sec:Concepts:Identity:Themes:Motifs}{}

\label{sec:Concepts:Identity:Themes:Motifs}

\begin{description}

\item[framework:] trunk/Identity/Themes/Motifs/

\end{description}

\noindent Here is where the themes' artistic motifs are produced. The

artistic motif is a graphic design used as common pattern to connect

all CentOS Project's visual manifestations inside the same theme.

Inside the framework location above, artistic motifs are organized by

names inside the standard file structure illustrated in

\autoref{fig:Concepts:Identity:Themes:Motifs:Default} and

\autoref{fig:Concepts:Identity:Themes:Motifs:Alternative}.

\begin{figure}[!hbp]

\hrulefill

\begin{verbatim}

trunk/Identity/Themes/

|-- Motifs

|   |-- Modern              <-- theme name.

|   |   |-- Backgrounds

|   |   |-- Distro

|   |   |   |-- Anaconda

|   |   |   |   |-- Header

|   |   |   |   |-- Progress

|   |   |   |   |-- Prompt

|   |   |   |   `-- Splash

|   |   |   |-- BootUp

|   |   |   |   |-- Firstboot

|   |   |   |   |-- GDM

|   |   |   |   |-- GRUB

|   |   |   |   |-- GSplash

|   |   |   |   |-- KDM

|   |   |   |   |-- KSplash  

|   |   |   |   |-- RHGB

|   |   |   |   `-- Plymouth

|   |   |   `-- Desktop

|   |   |-- Info

|   |   |-- Palettes

|   |   |-- Promo

|   |   |-- Screenshots

|   |   `-- Web

|   |-- ... more theme names.

\end{verbatim}

\hrulefill

\caption{Theme motifs default structure.%

   \label{fig:Concepts:Identity:Themes:Motifs:Default}}

\end{figure}

\begin{figure}[!hbp]

\hrulefill

\begin{verbatim}

trunk/Identity/Themes/

|-- Motifs

|   |-- TreeFlower          <-- theme name.

|   |   |-- Backgrounds

|   |   |-- Distro

|   |   |   |-- BootUp

|   |   |   |   |-- Firstboot

|   |   |   |   |-- GDM

|   |   |   |   |-- GRUB

|   |   |   |   |-- GSplash

|   |   |   |   |-- KDM

|   |   |   |   |-- KSplash  

|   |   |   |   |-- RHGB

|   |   |   |   `-- Plymouth

|   |   |   `-- Desktop

|   |   |-- Info

|   |   |-- Palettes

|   |   |-- Screenshots

|   |-- ... more theme names.

\end{verbatim}

\hrulefill

\caption{Theme motifs alternative structure.%

   \label{fig:Concepts:Identity:Themes:Motifs:Alternative}}

\end{figure}

When designing artistic motifs for CentOS, consider the following

recommendations:

\begin{itemize}

\item Give a unique (case-sensitive) name to your Motif. This name is

used as value wherever theme variable (\$THEME) or translation marker

(\texttt{=THEME=}) is.  Optionally, you can add a description about

inspiration and concepts behind your work.

\item Use the location trunk/Identity/Themes/Motifs/\$THEME/ to store

your work. If it doesn't exist create it. Note that this require you

to have previous commit access in CentOS Artwork Repository.

\item The CentOS Project is using the blue color (\texttt{\#204c8d})

as base for its corporate visual identity. Use the CentOS Project's

base corporate color as much as possible in your artistic motif

designs.

\item Try to make your design fit one of the

``\hyperlink{sec:Concepts:Identity:Themes:Models}{Theme Models}''

(\autoref{sec:Concepts:Identity:Themes:Models}).

\item Feel free to make your art enterprise-level and beautiful.

\item Add the following information on your art work (both in a visible

design area, and inside Inkscape's document metadata section wherever

it be possible):

\begin{itemize}

\item The name (or logo) of your artistic motif.

\item The copyright sentence: \texttt{Copyright (C) YEAR YOURNAME}

\item The license under which the work is released. All CentOS Art

works are released under

\href{http://creativecommons.org/licenses/by-sa/3.0/}{Creative Common

Share-Alike License 3.0}

(\href{http://creativecommons.org/licenses/by-sa/3.0/}{http://creativecommons.org/licenses/by-sa/3.0/}).

\end{itemize}

\end{itemize}

% ------------------------------------------------------------

\section{Theme Palettes}

\hypertarget{sec:Concepts:Identity:Themes:Palettes}{}

\label{sec:Concepts:Identity:Themes:Palettes}

\begin{description}

\item[framework:] turnk/Identity/Themes/Motifs/\$THEME/Palettes/\\

\end{description}

\noindent Here is where graphic designers define theme palettes for

color-limited art works. Theme palettes contain the color information

that rendering functions need, in order to produce images with color

limitations.  Theme palettes contain theme's unique color information.

\autoref{tab:Concepts:Identity:Themes:Palettes:Files}.

% ------------------------------------------------------------

\section{Theme Palettes Creation}

\hypertarget{sec:Concepts:Identity:Themes:Palettes:Creation}{}

\label{sec:Concepts:Identity:Themes:Palettes:Creation}

Theme palettes are based on art works' specific color information you

are creating palettes for. As we write this section, there are two art

works that require color limitations. They are Grub and Syslinux art

works.

This section describes a generic procedure you can use to create theme

palettes for art works which need to be produced with color

limitations.

\begin{enumerate}

\item As first step, you need to produce a PNG file with the final

design of that art work you are creating palettes for.  You can do

this by using the \texttt{render.sh} script available in the art

work's identity framework.

\item Secondly, you need to generate the limited color information for

that PNG file the three different file formats (See

\autoref{tab:Concepts:Identity:Themes:Palettes:Files}). You can do

this by using the Gimp as described below: 

\begin{table}[!hbp]

\center

\begin{tabular}{ll}

\hline

\textbf{File} & \textbf{Description}\\

\hline

\texttt{.gpl} & Gimp palette files.\\

\texttt{.ppm} & Portable Pixel Map palette files.\\

\texttt{.hex} & Hexadecimal auxiliar palette files.\\

\hline

\end{tabular}

\caption{Palette file types.% 

   \label{tab:Concepts:Identity:Themes:Palettes:Files}}

\end{table}

\end{enumerate}

To create the \texttt{.gpl} file:

\begin{enumerate}

\item Open the Gimp (\textit{Applications / Graphics / The Gimp}).

\item Open the PNG format file you want to generate the limited color

information for (\textit{File / Open ...}).

\item Index the image (\textit{Image / Mode / Indexed...}).  This will

open the window ``Indexed Color Conversion''. Use this window to

``Generate optimum palette'' by setting the maximum number of colors

you want to have in the final indexed image. In this window, by the

default, Gimp has set 255 as the maximum number of colors, you should

change this value to fit the art work color limitation requirements

(i.e. 14 colors for Grub's splash, and 16 colors for Syslinux splash,

etc.). Another option you can play with is ``Color dithering'' at the

window's bottom, particularly the ``Floyd-Steinberg (reduced color

dithering)'' option which seems to archive the best results.

\item At this point you have reduced color information and indexed the

image. This let you save the color information as a Gimp palette file

(.gpl) for further using. 

To export the color information as Gimp palette you need to open the

palette window (\textit{Ctrl+P}) and go to the action ``Import

Palette...'' inside ``Palettes Menu''. This will open the window

``Import Palette''. In this window you need to specify the source from

where you will retrive color information and the name of the palette

file. Use ``Image'' as source to create your palette and the

appropriate name (e.g., \texttt{centos-\$themename-grub}).\footnote{in

\texttt{centos-\$themename-grub} file name, the \texttt{\$themename}

part is the theme's name you are working on (e.g., Modern, TreeFlower,

etc.) for Grub's palette, \texttt{centos-\$themename-syslinux} for

Syslinux palette, etc.}

\end{enumerate}

To create the \texttt{.ppm} file:

\begin{enumerate}

\item Use the Gimp to create a new image (\textit{Ctrl+N}) of 16 x 1

pixels of dimension.  That is 16 pixels width and 1 pixel height.

\item That is a rather small image so you problably want to zoom it in

to better see what you are doing. In a 1024x768 screen resolution,

zoom the 16 x 1 pixel image to 4500\% makes things clear enough. If

you are using a different screen resolution you probably need to zoom

in to a different value. 

\item Now it's time to fill up the empty image with the color

information we created previously. You do this using the pen tool

(\textit{N}) with a 1x1 brush (\textit{Shit+Ctrl+B}). At this point it

is a good time to open the ``Palette Editor'' window and use the Gimp

palette file with the color information we created (\textit{Ctrl+P /

doble click on the palette file}).

\begin{quote} 

\textbf{Caution!:} If you are creating \texttt{.ppm} palettes for

Anaconda prompt (syslinux), the order used to set the color

information is relevant. Relevant values in the image are positions: 0

and 7.  Position 0 is used as background color, which is black

(\texttt{\#000000}) generally and position 7 is used as forground

color, which is white (\texttt{\#ffffff}) generally. This, in order to

grant the highest contrast.  See

\autoref{fig:Concepts:Identity:Themes:Palettes:Syslinux}.

\end{quote}

\end{enumerate}

To create the (\texttt{.hex}) file:

\begin{enumerate}

\item Create a plain text file and put the hexadecimal color

information and its index position defined in \texttt{.ppm} palette

inside the file, one definition by line.  The format used to create

the \texttt{.hex} file is \texttt{\#rrbbgg=i \dots}.  Where

\texttt{\#rrggbb=i} indicates that the color \texttt{\#rrggbb} (hex)

should be assigned index i (decimal).

\begin{quote}

\textbf{Caution!:} In order to produce Anaconda prompt (syslinux)

images correctly, both \texttt{.hex} and \texttt{.ppm} color and index

information should match.

\end{quote}

\end{enumerate}

\begin{figure}[!hbp]

\begin{center}

\fbox{\includegraphics[width=0.8\textwidth]{%

   /home/centos/artwork/trunk/Identity/Models/Img/en/Distro/Anaconda/Prompt/syslinux-palette.pdf}}

\end{center}

\caption{Palette's background (A) and forground (B) color position.%

    \label{fig:Concepts:Identity:Themes:Palettes:Syslinux}}

\end{figure}

% ------------------------------------------------------------

\section{Theme File Structure}

\hypertarget{sec:Concepts:Identity:Themes:Files}{}

\label{sec:Concepts:Identity:Themes:Files}

Inside CentOS Artwork Repository, each theme has a name and a

directory for it. Inside each theme directory, the CentOS Project

visual style is organized in the directories: Distro, Info, Palettes,

Promo, Screenshots, and Web. 

% ------------------------------------------------------------

\subsection{The \texttt{Distro} Directory}

\hypertarget{sec:Concepts:Identity:Themes:Files:Distro}{}

\label{sec:Concepts:Identity:Themes:Files:Distro}

Here is where image files controlling CentOS Distribution visual style

are produced. 

\begin{figure}[!hbp]

\hrulefill

\begin{verbatim}

turnk/Identity/Themes/Motifs/$THEME/Distro/

|-- Anaconda

|   |-- Header

|   |-- Progress

|   |-- Prompt

|   `-- Splash

|-- BootUp

|   |-- Firstboot

|   |-- GDM

|   |-- GRUB

|   |-- GSplash

|   |-- KDM

|   |-- KSplash

|   `-- RHGB

`-- Desktop

\end{verbatim}

\hrulefill

\caption{The CentOS distribution theme structure.}

\end{figure}

% ------------------------------------------------------------

\subsection{The \texttt{Palettes} Directory}

\hypertarget{sec:Concepts:Identity:Themes:Files:Palettes}{}

\label{sec:Concepts:Identity:Themes:Files:Palettes}

Here is where theme's palettes are sotred. Palettes are used to

automate image rendering in cases where a limited amount of color need

to be specified. Before you could render color-limited art works (e.g.

Grub, and Syslinux), you need to create their color-limited palettes

first. See

``\hyperlink{sec:Concepts:Identity:Themes:Palettes:Creation}{Theme

Palette Creation}''

(\autoref{sec:Concepts:Identity:Themes:Palettes:Creation}).

% ------------------------------------------------------------

\subsection{The \texttt{Promo} Directory}

\hypertarget{sec:Concepts:Identity:Themes:Files:Promo}{}

\label{sec:Concepts:Identity:Themes:Files:Promo}

Here is where image files controlling CentOS promotion visual style

are produced.

% ------------------------------------------------------------

\subsection{The \texttt{Screenshots} Directory}

\hypertarget{sec:Concepts:Identity:Themes:Files:Screenshots}{}

\label{sec:Concepts:Identity:Themes:Files:Screenshots}

Here is where theme's screenshots are stored. The purpose of this

directory is to collect theme's implementation graphical history

through time. Inside this directory you can have distribution

screenshots, web sites screenshtos, and promotion screenshots. If

theme has been implemented out of computers like would be the case of

events, stands, etc. those photos can be added here too, in the

promotion screenshot section.

% ------------------------------------------------------------

\subsection{The \texttt{Web} Directory}

\hypertarget{sec:Concepts:Identity:Themes:Files:Web}{}

\label{sec:Concepts:Identity:Themes:Files:Web}

Here is where image files controlling CentOS Web sites visual style

are produced.