\input texinfo   @c -*-texinfo-*-

@c %**start of header
@setfilename libgamma.info
@settitle blueshift
@afourpaper
@documentencoding UTF-8
@documentlanguage en
@finalout
@c %**end of header


@dircategory Library
@direntry
* libgamma: (libgamma).            Display server abstraction layer for gamma ramp adjustments
@end direntry


@copying
Copyright @copyright{} 2014 Mattias Andrée

@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
Texts. A copy of the license is included in the section entitled
``GNU Free Documentation License''.
@end quotation
@end copying

@ifnottex
@node Top
@top libgamma -- Display server abstraction layer for gamma ramp adjustments
@insertcopying
@end ifnottex

@titlepage
@title libgamma
@subtitle Display server abstraction layer for gamma ramp adjustments
@author by Mattias Andrée (maandree)

@page
@c @center `'
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents



@menu
* Overview::                        Brief overview of @command{libgamma}.
* Compiling::                       Configuring, compiling and installing @command{libgamma}.
* GNU Free Documentation License::  Copying and sharing this manual.
@end menu



@node Overview
@chapter Overview

@command{libgamma} is a C library that aims to
abstract away the display server when adjusting
the colours curves for monitors via gamma ramps,
and to be cross-platform.

@command{libgamma} have support for the X RandR
(Resize and Rotate) extension, the X VidMode
extension and under Linux the Direct Rendering
Manager which lets software work with graphics
outside of graphical environments. Additionally
@command{libgamma} have support for Windows
Graphics Device Interface (Windows GDI) under
Linux and Quartz using CoreGraphics under OS X.
However Windows GDI and Quartz/CoreGraphics do
not receive first-party testing on their target
platforms but do receive first-party testing
using a compatibility layer that translates
the calls to RandR calls. Neither does libgamma,
currently, receive testing on any of the BSD:s,
it is only tested on GNU/Linux.

Furthermore @command{libgamma} provides a dummy
method that can be used to ignore adjustments
and can be controlled from a another program to
pretend like the environment has changed. This
can be used test how well your software handles
such events. It can also be configured at runtime
to use another adjustment method such as RandR.



@node Compiling
@chapter Compiling

The build @command{libgamma} you will need
to run @command{./configure} before you
run @command{make}. @file{./configure} is
not a configuration script from the GNU build
system, rather it is just a simple shell script.
Each adjustment method needs selected, if none
are selected no adjustment method will be compiled
into @command{libgamma}. They can either be
selected explicitly and independently or by
operating system:

@table @option
@item --enable-dummy
Enables the dummy adjustment method.

@item --enable-randr
@itemx --linux
@itemx --bsd
Enables the X RandR extension adjustment method.

@item --enable-vidmode
@itemx --linux
@itemx --bsd
Enables the X VidMode extension adjustment method.

@item --enable-drm
@itemx --linux
Enables the Direct Rendering Manager adjustment method.

@item --enable-w32gdi
@itemx --windows
Enables the Windows GDI adjustment method.

@item --enable-quartz
@itemx --mac-os-x
Enables the Quartz/CoreGraphics adjustment method.

@item --enable-w32gdi=fake
Enables the Windows GDI adjustment method using
compatibility layer to either RandR or ``/dev/null''
depending on whether RandR is enabled or not.

@item --enable-quartz=fake
Enables the Quartz/CoreGraphics adjustment method
using a compatibility layer to either RandR or
``/dev/null'' depending on whether RandR is
enabled or not.

@end table

You may prefix anything to `bsd', for example
@option{--freebsd} or @option{--openbsd}. Any
prefix will be discard, but it may be a good
idea incase there will be a difference in the
future between the platforms.

Developers of @command{libgamma} and developers
who use @command{libgamma} for their software may
also want to use @option{--debug} which enables
extra checks to produce better error reports.
Additionally @option{--debug} adds the @option{-Og -g}
flags to the C compiler rather than @option{-Ofast}.
Developers can also use the developer options
instead of @option{--debug}, the adjustment and
operating systems:

@table @option
@item --linux=developer
@itemx --developer
Enables all adjustment methods, with compatibility
layers for Windows GDI and Quartz/CoreGraphics.
Also enables @option{--debug}.

@item --bsd=developer
Enables all adjustment methods, except the Linux
Direct Rendering Manager adjustment method, with
compatibility layers for Windows GDI and
Quartz/CoreGraphics.
Also enables @option{--debug}.

@item --windows=developer
Enables the dummy adjustment method and the
Windows GDI adjustment method.
Also enables @option{--debug}.

@item --mac-os-x=developer
Enables the dummy adjustment method and the
Quartz/CoreGraphics adjustment method.
Also enables @option{--debug}.
@end table



@node GNU Free Documentation License
@appendix GNU Free Documentation License
@include fdl.texinfo

@bye