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# -*- python -*-

# This example uses free function modifier and temporary
# curve linearisation to make the colour curves logarithmic.


# Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
# 
# 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, no Front-Cover Texts, and no Back-Cover Texts.
# You should have received a copy of the GNU General Public License
# along with this software package.  If not, see <http://www.gnu.org/licenses/>.


import math

# Use linear RGB.
linearise()

# Make the curves logarithmic. The function applies
# to the red (first argument) and green (second
# argument) colour curves. `...` is used to use the
# same value as the argument before it. `None`,
# which is used for the blue colour curve, means
# that no adjustment is made, which is the same
# thing as using `lambda x : x`.
manipulate(lambda x : math.log(x + 1, 2), ..., None)

# Switch back to sRGB.
standardise()

# Alternatively you can use `cie_manipulate` instead
# of `manipulate`. To to the logaritmisation in the
# CIE xyY colour space. If doing so, do not use
# `linearise`–`standardise`.

# Apply settings, using vidmode.
(drm if ttymode else vidmode)()
#(drm if ttymode else randr)()