Spook Season Gaming: Super Metriod

Howdy, strangers! Geez, it’s been a while since I blogged. I apologise for not having a lengthy, in-depth article for you, but I haven’t had enough time or desire to sit down and write one.

Instead, I have a grudge to settle. Remember way back in the day, when we were fundraising for the site? I started playing Super Metroid to do my part, and got about two-thirds of the way through the game before wandering away. Well, guess whaaaat?… [Read more…]

Trying an Experiment

Usually when I get addicted to something, obsessing over it for a week or two is enough to get it out of my system. My Minecraft addiction has been going strong for a month and a half, though, with [no] signs of abating. The time I used to use to daydream posts has instead been turned to testing the best design for a lava blade or roughing up a flexible design for a mountain home in Blender.

When pondering what to do about the situation, though, I realized something: I’m a noob, but not a complete one. Yes, I can say “mob grinder” with a straight face, but I’ve also died tonnes of times in order to establish my base. I still don’t have any enchantments, I can count the number of iron bars I own on one hand, but much of that tardiness is because I’ve been more focused on finding the right location for a home. I’m not bragging about my amazing builds or redstone skillz, but I’m also not flailing around either, and I haven’t seen a lot of Minecraft players with that intermediate skill level.

I figure it might be watchable. And if I’m putting in the hours, I might as well try my hand at streaming the game. And so, I have. I’ve currently got five videos up, in fact, though I hear Twitch deletes old videos unless you fork over cash. If videos start disappearing, I’ll archive them on YouTube.

Until that point, here’s a quick overview of what I’m hoping to build and the constraints I’ve placed on myself, then four more videos where I start executing on it. Looking back on the series, I’m still a bit amazed at the pace of improvement, on a technical level. There’s no way I can keep that pace up, but at least I can always craft more mines.

Ridiculously Complex

Things have gotten quiet over here, due to SIGGRAPH. Picture a giant box of computer graphics nerds, crossed with a shit-tonne of cash, and you get the basic idea. And the papers! A lot of it is complicated and math-heavy or detailing speculative hardware, sprinkled with the slightly strange. Some of it, though, is fairly accessible.

This panel on colour, in particular, was a treat. I’ve been fascinated by colour and visual perception for years, and was even lucky enough to do two lectures on the subject. It’s a ridiculously complicated subject! For instance, purple isn’t a real colour.

The visible spectrum of light. Copyright Spigget, CC-BY-SA-3.0.

Ok ok, it’s definitely “real” in the sense that you can have the sensation of it, but there is no single wavelength of light associated with it. To make the colour, you have to combine both red-ish and blue-ish light. That might seem strange; isn’t there a purple-ish section at the back of the rainbow labeled “violet?” Since all the colours of the rainbow are “real” in the single-wavelength sense, a red-blue single wavelength must be real too.

It turns out that’s all a trick of the eye. We detect colour through one of three cone-shaped photoreceptors, dubbed “long,” “medium,” and “short.” These vary in what sort of light they’re sensitive to, and overlap a surprising amount.

Figure 2, from Bowmaker & Dartnall 1980. Cone response curves have been colourized to approximately their peak colour response.

Your brain determines the colour by weighing the relative response of the cone cells. Light with a wavelength of 650 nanometres tickles the long cone far more than the medium one, and more still than the short cone, and we’ve labeled that colour “red.” With 440nm light, it’s now the short cone that blasts a signal while the medium and long cones are more reserved, so we slap “blue” on that.

Notice that when we get to 400nm light, our long cones start becoming more active, even as the short ones are less so and the medium ones aren’t doing much? Proportionately, the share of “red” is gaining on the “blue,” and our brain interprets that as a mixture of the two colours. Hence, “violet” has that red-blue sensation even though there’s no light arriving from the red end of the spectrum.

To make things even more confusing, your eye doesn’t fire those cone signals directly back to the brain. Instead, ganglions merge the “long” and “medium” signals together, firing faster if there’s more “long” than “medium” and vice-versa. That combined signal is itself combined with the “short” signal, firing faster if there’s more “long”/”medium” than “short.” Finally, all the cone and rod cells are merged, firing more if they’re brighter than nominal. Hence where there’s no such thing as a reddish-green nor a yellow-ish blue, because both would be interpreted as an absence of colour.

I could (and have!) go on for an hour or two, and yet barely scratch the surface of how we try to standardize what goes on in our heads. Thus why it was cool to see some experts in the field give their own introduction to colour representation at SIGGRAPH. I recommend tuning in.

 

Well, that’s Over

Starting out with a lie probably isn’t a good idea, but it’s the best summary I’ve got. I finally have a stretch of free time, and I’ve given myself explicit orders to kick back and relax. That includes poking away at this blog again, as poor ol’ Proof of God has suffered a fair bit of neglect and my list of rant topics is worth a rant in and of itself. But kicking back also means kicking out stuff like this:

Eyes Down. Copyright HJH, 2017.

It’s not my best work, but I’m also coming back into photo processing after a few year’s absence. I’ve never really been happy with my forest scenes (they always feel way too busy and unfocused), so I thought I’d crush the busy bits into blackness and draw your eye to the really cool bits: the texture of the snow. The desaturated high-detail look is practically a cliché nowadays, but I like it here (and I was hip to it before most, dammit!)