Considering Perl on Windows
I am writing on this idea for another site, but at this point, I don’t know what I’m going to write for that audience, so I’m gonna write for myself and see if I can come up with a thought as to what I need to write for others.
Why?
Once, long ago, I saw it presented that Perl is the Cliff Notes for Unix. (A quick search for that phrase attributes it to Larry Wall. I don’t believe I read it from Larry, but I’m happy with that thought.) In work environments where I didn’t have Unix, I went to Cygwin and ActiveState Perl to get myself something that behaves like my beloved Unix when otherwise I had Windows Explorer and cmd.
These days, I have WSL, which gives me a full-on Linux userland in a Windows context, with the package manager of my OS of choice as well as cpanm for anything I might want. I hadn’t needed Perl on the Windows Side as well.
Except.
Sometimes I want to code Perl. Surprising, I know. Sometimes, that Perl is not meant to run on the local machine, but I still want perltidy and perlcritic and — honestly, mostly perltidy — and while there’s a VS Code extension for perltidy, it calls out to the real perltidy, so it would only work if I had it installed.
How?
I have used and liked ActiveState Perl which is and has been a perfectly wonderful and current Perl on Windows. ActiveState prepackages modules into PPMs, and that works. I don’t like rethinking how I admin Perl when I move to a new machine, so a while ago, I started using Strawberry Perl, which allows me to add modules with cpan and cpanm.
Additionally, Microsoft has been dipping it’s toes in packages starting with NuGet in Visual Studio, and then Chocolatey, from which you can install either Perl. There’s also [WinGet], which I know is shiny and new but haven’t used yet. You can install without a package manager, but getting the base to the new hotness is probably easier within one.
What do I do with it?
By and large, I want to do the same things that I would do on Linux, so “It’s Perl, so treat it like Perl”. But it would be good to engage with Windows-specific things.
I’ve never controlled the mouse position in Linux. Within Linux, I suppose. I once wrote code for an Arduino HID device that moved the mouse back and forth, so the screen would not lock, but I haven’t done it from the inside.
I can do it within Windows, with Win32::GUIRobot, however. I can get the dimensions of the screen, take screen shots and, yes, set (and click) the mouse with the power of Perl.
#!/usr/bin/env perl
use strict;
use warnings;
use feature qw{ say postderef signatures state };
no warnings qw{ experimental };
use Win32::GUIRobot qw{:all};
use Math::Trig qw(deg2rad);
my $width = ScreenWidth;
my $height = ScreenHeight;
my $depth = ScreenDepth;
# $x and $y are the coordinates for center of the screen,
# and the radius of the circle we're going to draw with the
# mouse pointer
my $x = $width / 2;
my $y = $height / 2;
my $rad = $height / 3;
# We're starting at -90 so we start at 12 o'clock
# instead of 3 o'clock, and we're going in this code
# by nines, because 360 was chosen to be evenly divisible
# by many numbers.
# note: programmers are lazy typists, and this is a problem
# here because we have radius, determining the size of the
# circle we're drawing, and radians, which is a mathematically
# more convenient way of expressing the angle than degrees.
# Don't be like me; make your variable names long.
for ( my $deg = -90 ; $deg <= 270 ; $deg += 9 ) {
my ( $nx, $ny ) = get_xy( $deg, $x, $y, $rad );
MouseMove $nx, $ny;
}
# this is the bit that turns the degrees into X,Y coordinates
# to move the mouse to. I mostly know this because I have fun
# writing clocks. Geometry is so fun!
sub get_xy ( $deg, $x, $y, $radius ) {
my $rad = deg2rad($deg);
my $nx = int $x + ( $radius * cos($rad) );
my $ny = int $y + ( $radius * sin($rad) );
return $nx, $ny;
}
I think I’m gonna have to make a video of this working.
How do you help?
If you know good modules within Win32 or otherwise Windows-centric that do cool but perhaps more useful things than make circles with a mouse pointer, hit me up.