X11::Protocol::Other(3) miscellaneous X11::Protocol helpers


use X11::Protocol::Other;


This is some helper functions for "X11::Protocol".


Nothing is exported by default, but the functions can be requested in usual "Exporter" style,

    use X11::Protocol::Other 'visual_is_dynamic';
    if (visual_is_dynamic ($X, $visual_id)) {

Or just called with full package name

    use X11::Protocol::Other;
    if (X11::Protocol::Other::visual_is_dynamic ($X, $visual_id)) {

There's no ":all" tag since this module is meant as a grab-bag of functions and to import as-yet unknown things would be asking for name clashes.


Screen Finding

"$number = root_to_screen ($X, $root)"
"$hashref = root_to_screen_info ($X, $root)"
Return the screen number or screen info hash for a given root window. $root can be any XID integer on $X. If it's not one of the root windows then the return is "undef".
"$number = default_colormap_to_screen ($X, $colormap)"
"$hashref = default_colormap_to_screen_info ($X, $colormap)"
Return the screen number or screen info hash for a given default colormap. $colormap can be any XID integer on $X. If it's not one of the screen default colormaps then the return is "undef".


"$bool = visual_is_dynamic ($X, $visual_id)"
"$bool = visual_class_is_dynamic ($X, $visual_class)"
Return true if the given visual is dynamic, meaning colormap entries on it can be changed to change the colour of a given pixel value.

$visual_id is one of the visual ID numbers, ie. one of the keys in "$X->{'visuals'}". Or $visual_class is a VisualClass string like ``PseudoColor'' or corresponding integer such as 3.

Window Info

"($width, $height) = window_size ($X, $window)"
"$visual_id = window_visual ($X, $window)"
Return the size or visual ID of a given window.

$window is an integer XID on $X. If it's one of the root windows then the return values are from the screen info hash in $X, otherwise the server is queried with "GetGeometry()" (for the size) or "GetWindowAttributes()" (for the visual).

These functions are handy when there's a good chance $window might be a root window and therefore not need a server round trip.

Colour Parsing

"($red16, $green16, $blue16) = hexstr_to_rgb($str)"
Parse a given RGB colour string like ``#FF00FF'' into 16-bit red, green, blue components. The return values are always in the range 0 to 65535. The strings recognised are 1, 2, 3 or 4 digit hex.


If $str is unrecognised then the return is an empty list, so for instance

    my @rgb = hexstr_to_rgb($str)
      or die "Unrecognised colour: $str";

The digits of the 1, 2 and 3 forms are replicated as necessary to give a 16-bit range. For example 3-digit style ``#321FFF000'' gives return values 0x3213, 0xFFFF, 0. Or 1-digit ``#F0F'' is 0xFFFF, 0, 0xFFFF. Notice ``F'' expands to 0xFFFF so an ``F'', ``FF'' or ``FFF'' all mean full saturation the same as a 4-digit ``FFFF''.

Would it be worth recognising the Xcms style ``rgb:RR/GG/BB''? Perhaps that's best left to full Xcms, or general colour conversion modules. The X11R6 X(7) man page describes the ``rgb:'' form, but just ``#'' is much more common.


Copyright 2010, 2011, 2012, 2013 Kevin Ryde

X11-Protocol-Other is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.

X11-Protocol-Other is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with X11-Protocol-Other. If not, see <http://www.gnu.org/licenses/>.