Pew Pew Laser Blog Hand forged code from Seattle, Washington. Gaming - analog and digital. Glass artistry. Baking. And a few pictures of cats. en-us Pew Pew Laser Blog Inkscape - Using Path > Difference With Text. Sat, 03 Mar 2018 00:00:00 PST It turns out that Inkscape's error messages will appear in the status bar at the bottom of the application.

Part of getting my Glowforge laser cutter has been learning to use a new piece of software, Inkscape. I was having problems using Inkscape's "Path > Difference" option to combine (well, cut out) shapes and text elements. Here's what I had to do to get the elements merged:

  1. Optional: Disable any stroke styles on both objects. Use fills instead.
  2. Optional: Make sure the first element - the non-text - is a path. Select it and choose "Path > Object to Path".
  3. Turn the text into a path. Select it and choose "Path > Object to Path".
  4. Ungroup that new path. Right click it and choose "Ungroup".
  5. Bring the "top" element to the top layer (Home). This is what will be removed from the other element.
  6. Position / align the elements as desired.
  7. Select both of the elements.
  8. Choose "Path > Difference".
Katie Kurkoski
Global Diversity CFP Day Q&A. Tue, 06 Feb 2018 00:00:00 PST Last week was Global Diversity CFP Day and we held the Seattle workshop that I'd been organizing for a few months. Global Diversity CFP Day was started by Peter Aitken, who ran a similar event to improve the diversity of submissions for his event ScotlandJS. At the event, a number of locations world-wide held workshops where people who are under-represented at technology conferences could learn about submitting talks to conferences from experienced speakers and event organizers. The attendees asked some really good questions, so I figured I'd answer them here for posterity. I hope readers will forgive me for including one "Socratic method" question at the end.

  • What is a "CFP?"

    It stands for "call for proposals" or sometimes "call for papers". It comes from academic conferences making it known that they are looking for content for their meetings and conferences. In my experience, tech conferences use to indicate that talk submissions are open to anyone who fills out the online form.

  • How did you get involved in this?

    I attended a local meetup and learned about a local conference that had just happened. I continued attending meetups, and following interesting people on Twitter, and started beginning to think that perhaps I could speak too. I talk more about getting involved with organizing conferences here.

  • Do conferences pay?

    It depends, greatly.

    A few conferences pay their speakers a fee, in addition to covering the speaker's travel, lodging and conference ticket. Some of these pay only some of their speakers a fee. These conferences are usually - but not always - organized for a profit.

    Most of the conferences I pay attention to usually - but not always - cover a speaker's travel, lodging and conference ticket, but it is much more rare to pay a speaker fee. These are usually organized by volunteers in their "spare" time, and some are even 501c3 non-profit organizations.

    Some conferences will cover some fees if you ask, and other conferences don't pay for anything - even when the speakers are providing the content! This is more common in academic and open-source conferences, where the expectation seems to be that your employer will cover conferences costs.

    Conferences usually publish what they cover along with their CFP. It's up to you to make the call as to whether speaking at that particular conference works for you. For me, it doesn't make any sense to pay out of my own pocket to speak at a conference.

  • Do you write the talk before the proposal?

    No, almost never. For one, writing the proposal gives me the outline of what's going to be in the talk. More importantly, I don't do speculative work; so I don't write a talk before it's accepted at a conference. I have made one or two exceptions when I just knew it was a good talk, and I was determined to give it at a local meetup.

  • How do you find open calls for proposals?

    Twitter is huge in my sphere of influence. Following JSConf EU is a good start. Mozilla Tech CFPs is also a great way to get notified of CFPs which are closing soon. HackyGoLucky has a crowd-sourced spreadsheet of conferences at The Global Diversity CFP Day workhops have also put together a list at

  • How do you identify the culture of a conference; what kind of talks do they tend to accept and where do they fall on the silly vs. stodgy scale?

    I usually start by looking at the Twitter accounts for the conference itself, and its organizers. From this I can get a sense of how they interact with the community. The conference's website is usually all about the upcoming conference, but often archives the previous years too (try changing 2018 to another year in the URL). Looking at a previous year will tell you what talks they did accept, and those little descriptions of the talks were usually part of the CFP that the speaker sent in. If the conference records its talks, then you can watch videos of last year's talks - the keynote and MC sections can be particularly enlightening.

  • How do I find technical topics for the core of my talk?

    For me, technical topics commonly come out of bits of "fiddling with code" that I do. I can browse through my old Codepens and get some ideas about what's interesting. Also, when I've accomplished something in an evening of experimentation, I often think "I should share this!" and a few related topics can be the foundation of a talk. Even when working, any solution that can be abstracted and shared can be part of a talk.

  • How does going to local meetups improve my proposals and talks?

    One thing about meetups is that they're a lot like itty-bitty conferences. Attending conferences is definitely a way to get involved with the community, but attending meetups will get you involved with the community too. At a meetup, you can meet other people with the same interests and talk about current projects. When you're talking about something and the other people lean in and say "oh, that's interesting", then you might have a talk idea right there. Often, conference volunteers and organizers attend these meetups. Also, meetup organizers need to have a few talks each and every month of the year, so they are very likely to accept your talk. You can get very helpful feedback from attendees (What did they take away from the talk? What was confusing?) after giving a meetup talk.

Katie Kurkoski
Games I've Beat. Mon, 15 Jan 2018 00:00:00 PST Gender-based marketing is lazy and video game marketing has been lying to you. Here is a list of video games that I have beat. Where "beat" means variously beat the final boss, won all races or levels, or completed the story, as appropriate for the genre.

Katie Kurkoski
Keyboard Shortcuts for Web Dev Tools Inspector and Console. Thu, 07 Dec 2017 00:00:00 PST Sometimes, right clicking on something in a browser and picking "Inspect" from the context menu just isn't fast enough for me. I wanted to find a way to quickly open the Inspector and Console tabs in a browser's web developer tools, so naturally I turned to keyboard shortcuts. I've compiled a reference of the commands for Firefox and Chrome here.


  • Inspector: Ctrl Shift c (Cmd Option c on OSX)
  • Console: Ctrl Shift k (Cmd Option k on OSX)

Even better, the Web Dev tools will open up - with the last active tab - when you hit your F12 key. (In OSX, use fn F12 if you haven't enabled the "Use all F1, F2, etc keys as standard function keys" Keyboard Preference.)


  • Inspector: Chrome doesn't have a keyboard shortcut specific to "Elements" (Inspector), but Ctrl Shift i (Cmd Option i on OSX) will open the most recently used tab, just like F12.
  • Console: Ctrl Shift j (Cmd Option j on OSX)
Katie Kurkoski
The <code>DL</code> Element. Tue, 14 Nov 2017 00:00:00 PST At a conference earlier this year, I was asked what my favorite HTML element was. In fact, I do have one: the Definition List, along with its children Definition Term and Definition Description. The definition list is great because it provides an inherent semantic relationship between two elements - the term and the one or more descriptions. I feel like these elements are under-used; especially considering that they've been around since HTML 4.01.

I was going to invent a clever example to demonstrate the definition list, but I don't think I can do any better than the one provided by the Mozilla Developer Network:

A free, open source, cross-platform, graphical web browser developed by the Mozilla Corporation and hundreds of volunteers.
The Red Panda also known as the Lesser Panda, Wah, Bear Cat or Firefox, is a mostly herbivorous mammal, slightly larger than a domestic cat (60 cm long).

Here is the source code for that:

  <dd>A free, open source, cross-platform, graphical web browser developed by the Mozilla Corporation and hundreds of volunteers.</dd>
  <dd>The Red Panda also known as the Lesser Panda, Wah, Bear Cat or Firefox, is a mostly herbivorous mammal, slightly larger than a domestic cat (60 cm long). </dd>

This shows one term (Firefox) along with two definitions of that term. Because it's a list, you can add as many groups of terms and definitions as needed for your content.

Katie Kurkoski
Virtual Reality. Mon, 23 Oct 2017 00:00:00 PDT An attendee tests VR goggles at JSConf Last Call Folks love to post pictures of people using virtual reality (VR) googles, because everyone just looks so darn goofy with the headset on. But virtual reality really does have legs. In the past couple years, I've seen some truly convincing VR demos, and run across amazing uses for VR. (Photo by Matthew Bergman from JSConf Last Call; CC BY-NC-ND 2.0.)

This year, 3 friends and I played a demo of Marvel Powers United VR on 4 fully loaded Oculus setups with motion sensitive headsets and hand-held controllers. A single set of this gear costs multiple hundreds of dollars. When my system booted up, I was The Hulk - I was taller than everyone, my strides consumed feet like they were inches, and I could grab puny humans by their baseball-size skulls. It was unbelievably immersive; my brain easily believed in this new reality. I only experienced a little motion sickness; see (this for more on gender and VR motion sickness).

With any one of a number of electronic headsets and their companion apps, you can record and view panoramic or even 720° photos (some with even ambient sound). You can then view these high-resolution photos on the headset where moving your head moves the view of the photo. I've had demos of this too, and they're also very immersive. Can you imagine immersing your family in your vacation photos like this? Or remember that folks with disabilities are often technology's earliest adopters - virtual environments like this would be huge for those with severe anxiety or people who have trouble traveling.

Think about watching your favorite sports team; with 3D sound and picture captured right on the sidelines? Beyond games and entertainment, the universal on-line educational system of "Ready Player One" seems tantalizingly close. If you ever get a chance to try out some of this technology, I highly recommend checking it out.

There are more utilitarian ways to utilize VR. Google offers Cardboard, a $15 set of "glasses" that you insert your smartphone into. As just one example of apps for Cardboard, here is one which simulates a conference stage, so that you can practice your public speaking.

If you're a developer, this is a great time to start working with VR technologies. A great place to start is Shagufta Gurmukhdas's SeattleJS Conf 2017 talk about VR and Mozilla's A-Frame.

Katie Kurkoski
OSX Screenshots. Sat, 30 Sep 2017 00:00:00 PDT In Windows, I use either the PrintScreen key or the Snip program for screenshots. But I can never remember the keyboard commands for screenshots in OSX, so here is a quick reference:

  • Shift Command 3: Capture the whole screen.
  • Shift Command 4: Use crosshairs to select an area to capture.

Both of the above methods will save the screenshot on your Desktop.

If I'm working in Firefox, I just use the built-in screenshot tools in Firefox too. (The files are saved in Downloads.)

Katie Kurkoski
Spinning Up a New GitHub Pages Site. Mon, 11 Sep 2017 00:00:00 PDT Pages might just be one of my favorite things about GitHub. Though I often use them for lists of links to go along with my presentations, they are capable of much more complex static sites.

Here is a quick reminder of how to set up a new GitHub Pages site:

  1. Create a new repo on GitHub.
  2. Don't create any new files yet, even licenses or readmes. If you have already created files, then stash them.
  3. Clone that repo locally and check out a new gh-pages branch (git checkout -b gh-pages).
  4. Pop any files you've stashed. Add any other files you want in your repo.
  5. Commit the changes, and then push the gh-pages branch up to Github.

You're done! You can now view your new page at https://[your-user-name][your-repo-name]/.

If you have somehow ended up with a master branch with commits, you can remove it thusly:

  • On the GitHub site, make the gh-pages branch the default.
  • Delete the master branch both on the GitHub site and locally.
Katie Kurkoski
Free Images. Tue, 22 Aug 2017 00:00:00 PDT Here are some sources for free images that you can use for your website, presentation, art project or whatever.

There are also companies which will give you free photos or credits on your first sign-up or periodically: iStock, Adobe Stock (fotolia), Shutterstock and Creative Market. And both Google and Flickr will let you search for CC licensed photos.

Katie Kurkoski
tinylab Flashlight. Wed, 02 Aug 2017 00:00:00 PDT Photograph of a tinylab - an all-in-one arduino-compatible prototyping board. I've been fiddling around with my tinylab - an all-in-one prototyping board with an embedded Leonardo and a fair selection of components. I'd already got it working with Node and Johnny-Five. Next I wanted to do something which demonstrated interaction between the software and some real-world conditions.

Note that my tinylab (perhaps because it's an early crowd-funded version) doesn't have the breadboard shown in the current production versions of the tinylab. No worries - a mini breadboard (without the connector tabs) fits in there perfectly.

I made a "flashlight" - where an LED gets brighter when the hardware detects less ambient light. Since all the components on the tinylab are already built in, I didn't have to do any wiring. It's pretty easy to test by covering the photoresistor with your finger. Here is the code:

var five = require("johnny-five"), board, photoresistor;
var board = new five.Board();

board.on("ready", function(){

  var led1 = new five.Led(10);

  photoresistor = new five.Sensor({
    pin: "A2",
    freq: 500 // Data is polled every half second

  maxLight = 750 // Set this to the "high" value of light in your room.
  minLight = 250 // Set this to the "low" value of light in your room.
  lightRange = (maxLight - minLight) // Will change for different rooms.

  photoresistor.on("data", function() {

    currentLight = this.value;
    ledValue = (((currentLight - minLight) * 255) / lightRange); 
    ledValue = Math.max(ledValue, 0);  
    ledValue = Math.min(ledValue, 255);

    console.log("Photosensor: " + this.value + "     ledValue: " + ledValue); 
    led1.fade(ledValue, 500); // Smooth transition of LED brightness



You'll need to set the maxLight and minLight values for your environment.

With this experiment, you now have a way to read a value from your environment, report it to a computer, and act on it.

Katie Kurkoski