Advent of Code: The most wonderful time of year…

December is upon us! That means the latest edition of the Advent of Code is here.

The Advent of Code is essentially a daily programming challenge featuring a new problem each day through Christmas. The problems all relate to a certain theme. This year, it sounds like we’re going on an undersea adventure.

— Day 1: Sonar Sweep —

You’re minding your own business on a ship at sea when the overboard alarm goes off! You rush to see if you can help. Apparently, one of the Elves tripped and accidentally sent the sleigh keys flying into the ocean!

Before you know it, you’re inside a submarine the Elves keep ready for situations like this. It’s covered in Christmas lights (because of course it is), and it even has an experimental antenna that should be able to track the keys if you can boost its signal strength high enough; there’s a little meter that indicates the antenna’s signal strength by displaying 0-50 stars.

Your instincts tell you that in order to save Christmas, you’ll need to get all fifty stars by December 25th.

Collect stars by solving puzzles. Two puzzles will be made available on each day in the Advent calendar; the second puzzle is unlocked when you complete the first. Each puzzle grants one star. Good luck!

I’ll be partaking using my preferred language of choice: x86 assembly.

I kid, I kid. JavaScript.

The World of Yesterday by Stefan Zweig

This is an absolutely beautiful (yet heartbreaking) memoir written in the midst of World War II.

Completed in 1942 (and sent to his publisher just days before he and his wife took their lives), it provides an intimate and fascinating look at life in Europe during the end of the Victorian Era and through two world wars.

I think one of the most striking things about this book (especially in the later pages) is how mournful, almost hopeless, Zweig is about the state of Europe and the world as a whole. And it’s no surprise, right? He was an Austrain Jew who saw the home and the people he loved destroyed.

Take this passage, written about Paris. He lovingly describes his time in Paris after he graduated from university and how it was a city that could always make people happy.

“I had promised myself a present for the first year of my newly gained freedom—I would go to Paris. Two earlier visits had given me only a superficial knowledge of that city of inexhaustible delights, but I could tell that any young man who had spent a year there would be left with incomparably happy memories for the rest of his life. Nowhere but in Paris did you feel so strongly, with all your senses aroused, that your own youth was as one with the atmosphere around you. The city offers itself to everyone, although no one can fathom it entirely.”

And then a paragraph later, we get to the hard truth about the time period this book was written in:

“Of course I know that the wonderfully lively and invigorating Paris of my youth no longer exists; perhaps the city will never entirely recover that wonderful natural ease, now that it has felt the iron brand forcibly imprinted on it by the hardest hand on earth. Just as I began writing these lines, German armies and German tanks were rolling in, like a swarm of grey termites, to destroy utterly the divinely colourful, blessedly light-hearted lustre and unfading flowering of its harmonious structure. ”

Another powerful aspect of this book is that while reading, we know that he would soon take his life and he’d never get to see how this tragic story (World War II) ended and how the cities, art and music he loved would eventually recover.

The World of Yesterday by Stefan Zweig

Sid Meier’s Memoir!: A Life in Computer Games

The Civilization series is easily one of my favorite video games of all time. (See here, here, here, here and here). I have very fond memories of talking to my middle school teacher about various strategies to utilize within Civ I and I still vividly remember the wickedly cool box art.

So, it’s no surprise that I’d dig into the memoir of the man who created the games himself, Sid Meier.

It’s a nerdy trip through early computer gaming history and fostered a bunch of nostalgia for old DOS games that I used to play. It’s also a fantastic romp through the mind of a game designer.

There were a number of fun little quotes and life lessons, as well:

“I think that in life, as in game design, you have to find the fun. There is joy out there waiting to be discovered, but it might not be where you expected. You can’t decide what something’s going to be before you embark on it, and you shouldn’t stick with a bad idea just because you’re fond of it. Take action as quickly and repeatedly as possible, take advantage of what you already know, and take liberties with tradition. But most importantly, take the time to appreciate the possibilities, and make sure all of your decisions are interesting ones.”

Generating terrain maps

Recently, I went down a rabbit hole attempting to learn how to generate interesting looking maps for games (insert mind-blown-gif here). While I’m not going to be using Voronoi diagrams anytime soon,  I am still interested in attempting to generate Civilization-like maps.

Most map generation algorithms rely on perlin noise. I wanted to go a different route.

So far, these are the rules that I’ve come up with for my algorithm:

1. Create a grid of some given size (e.g., 100 x 50). Set all tiles to “ocean”.
2. Randomly pick 8 tiles (variable) across the map to seed as “land”.
3. Now iterate across all tiles on the map and build an array of tiles that are “ocean” tiles but have a land tile N/W/S/E of them.
4. Once you have this array, randomly pick a single value. Flip it from “ocean” to “land”
5. Repeat step 3 until a given number of tiles have been filled across the grid (e.g., for an “Earth-like planet”, 30% of tiles will be land).
6. Now, to add some additional randomness — iterate across all tiles and build an array containing all “land” tiles next to water (N/W/S/E).
7. Randomly pick 1, flip from land to ocean.
8. Repeat step 6 a given number of tries (e.g., 100).
9. Done! (Maybe)

Height maps, biomes and all that can come later. To quote Amit, whom I linked to earlier:

The most realistic approach would have been to define elevation first, and then define the coastline to be where the elevation reaches sea level. Instead, I’m starting with the goal, which is a good coastline, and working backwards from there.

Anyway, it’s been kind of neat to figure out.

Another example map, created using the above rules:

 

Troubleshooting a (Royal) Kludge (RK G68): Sleep issues with my swanky new mechanical keyboard

TL;DR After a lot of testing and isolating devices, I’ve determined that the RK G68 RF receiver for my swanky new mechanical keyboard causes my Windows 10 machine to wake up immediately after putting it to sleep. And I’m not sure how to fix it.

Join me on an epic journey of heartbreak, anger, loss, triumph and sadness as I try to diagnose some sleep issues.

—-

So, the issue is that if I manually put my computer to sleep (Start Menu -> Power -> Sleep), the machine goes to sleep, fans turn off, and all that. Sweet! Then, after about 5 seconds, it wakes right back up. Uh, what?

I’ve done a number of debugging and testing steps which I’ll outline below (hopefully, this helps some folks in the future).

Let’s do a couple of finger stretches, put on our hacker pants, and open up PowerShell (with admin access). We can run a nifty command called powercfg /requests

I see the following output:

DISPLAY:
None.

SYSTEM:
None.

AWAYMODE:
None.

EXECUTION:
None.

PERFBOOST:
[DRIVER] Legacy Kernel Caller
Power Manager

ACTIVELOCKSCREEN:
None.

Great! But not really super helpful. We visit our friend, Google, and I see that there is a command to disable this:

powercfg -requestsoverride Driver "Legacy Kernel Caller" System

You haven’t lived until you’ve copy and pasted random commands from the Internet into your terminal. Let’s do it! I run that and make the computer go to sleep again. Monitor turns off, fans spool down. Yes! Yes?

Obviously, it immediately wakes up. No dice.

Ah, ha! Maybe read the command first, dude? The issue here is that the Legacy Kernel Caller is in the PERFBOOST category, not SYSTEM category. That’s easy to fix.

…but it isn’t.

Of course, you can’t actually disable the driver for items in the PERFBOOST category. Of course.

Hey, Google…

Next up: A suggestion to check waketimers. I have no idea what that is, but sure: powercfg -waketimers

There are no active wake timers in the system.

Okay.

Yo, Goooooooogle… again!

Ah, another command! powercfg -lastwake

Now we’re getting somewhere. We see that this is a USB device that is waking the computer:

Wake History Count - 1
Wake History [0]
  Wake Source Count - 1
  Wake Source [0]
    Type: Device
    Instance Path: USB\VID_25A7&PID_FA70\8&e5ec113&0&4
    Friendly Name:
    Description: USB Composite Device
    Manufacturer: (Standard USB Host Controller)

But… how do we determine what it is? Looking at the path, we see VID and PID. That means:

Vendor ID: 25A7
Product ID: FA70

Let’s Google those: It turns out, the vendor is Areson Technology Corp and it looks like they make RF receivers for various input devices, such as wireless mice. Interesting! No hits for the product ID. That’s fine, there’s probably more types of RF receivers on planet Earth than there are people.

But that gives me a starting point.

I decide to start unplugging various devices and put my computer to sleep.

  • Unplug Logitech USB receiver: Still wakes up.
  • Unplug Anker USB Bluetooth receiver / transmitter: Still wakes up. I feel like I’m not having much fun anymore.
  • Unplug this random, unlabeled RF receiver: Hey, my keyboard input stopped working from my mechanical keyboard! Ah well. Go to sleep computer…

IT DOESN’T WAKE BACK UP!!!!

Victory. Party dance. Switch out the hacker pants for party pants. Now we’re getting somewhere!

I plug the receiver back in and open device manager. I go to the keyboard section (randomly, there are like 4 different devices listed there). I open the properties dialog box for each of them, go to the Power Management tab and uncheck “Allow this device to wake the computer.

I got you now, pesky sleep problems! :blow-smoke-off-gun-gif-dot-com-dot-net:

I put the computer to sleep.

IT IMMEDIATELY WAKES BACK UP!

I’ll be honest. There was a lot of screaming, kicking, swearing. My dog got up and left the room (he never does that). I almost knocked over a coffee cup onto my keyboard and I DIDN’T CARE.

Okay, fine.

No big deal, really. I’m not okay, you’re okay.

On a hunch, I expand the Universal Serial Bus controllers section inside the device manager. Sure enough, there are a bunch of things that say USB Composite Device. You might remember from earlier (but probably not), that a “USB Composite Device” was called out using the --lastwake command.

If you open up the properties for each USB Composite Device and go to the events tab, you will see the device ID in the information section. Keep looking until you find the device ID that was called out: USB\VID_25A7&PID_FA70\8&e5ec113&0&4

Click. Close. Click. Close. Click. FOUND IT!

Device USB\VID_25A7&PID_FA70\8&e5ec113&0&4 was configured.

Driver Name: usb.inf
Class Guid: {36fc9e60-c465-11cf-8056-444553540000}
Driver Date: 06/21/2006
Driver Version: 10.0.19041.488
Driver Provider: Microsoft
Driver Section: Composite.Dev.NT
Driver Rank: 0xFF2003
Matching Device Id: USB\COMPOSITE
Outranked Drivers: 
Device Updated: false
Parent Device: USB\VID_0BDA&PID_5411\7&b8f002b&0&2.

Sweet, now to just open up the Power M…. THERE IS NO POWER MANAGEMENT TAB.

My dog came back. He immediately left again. You can probably guess why.

Back to Google again:

“Ensure drivers are updated”.

Okay. Sure. Blah, blah. But maybe it’ll work. It won’t though. I already know. Who am I kidding?

The best drivers for your device are already installed.

Fine. I’ll just uninstall the driver.

Oh, cool, now my keyboard doesn’t work.

BUT YOU KNOW WHAT?! MY COMPUTER STAYS ASLEEP!

Head, meet Desk. Desk, meet Head.

—-

A few other things to note.

    • If I have a USB-C cable plugged into the keyboard, it will stay asleep (even though the RF receiver is still plugged in).
    • If I turn off the keyboard itself, it will stay asleep.
    • If you just walk away from the computer, it will go to sleep (according to my power plan settings — 15 minutes). I suspect this is because the RK software (I’m on version 2, by the way, which I think just came out and the latest firmware) is setup to put the keyboard to sleep after about 5 minutes or so. I really haven’t tried to experiment with this because I DON’T CARE ANYMORE.

(I do care. Deeply. I just can’t right now.)