Color: rules

How a round works, what the difficulty levels change, how a colour distance turns into a score, and what streak, level and replay mean.

The goal

You are shown a colour, memorise it and then mix it again from memory. The closer you get to the original, the more points you score. Colour is not a property of the world but an achievement of the mind, and the exact shade fades there within seconds: that is precisely the task.

How a round works

1. Pick a difficulty level and press "Start game". After a short "ready, steady, go" the round begins.
2. The target colour fills the screen and a ring shows the memorising time running out. Look at it, there is nothing else to do.
3. Then it disappears and three vertical sliders appear: hue, saturation and brightness. From now on the area shows your current mix live.
4. Recreate what you saw. Take as long as you like; time does not enter the score.
5. Press "Confirm colour" to submit. The reveal places both colours side by side, shows the score as a ring and adds a verdict.
6. In "5 matches" the next round follows. After the fifth comes the overall summary with all five pairs. You can quit at any time with the cross in the top right or with Escape.

The two modes

Both play the same way and differ only in how many rounds they cover.

• Quick game: a single round, up to 100 points. It is saved with its result immediately.
• Five matches: five rounds in a row, up to 500 points. Nothing is saved before the fifth round; quit earlier and you leave no entry.

The difficulty levels

The level changes two things: how long you see the colour, and how strictly the measured distance is judged afterwards. The task itself stays the same.

• Easy: five seconds of memorising time, undisturbed. Judging is generous, the measured distance counts at three quarters.
• Normal: two seconds of memorising time with a subtle darkening at the edge. The distance counts unchanged.
• Hard: seven seconds, but only the first two show anything. A soft darkening closes in from the outside, after two seconds everything is black, and it stays black for the remaining five. The distance counts at a factor of 1.35, so it is judged more strictly than elsewhere.

The three sliders

You mix not in red, green and blue but in the three quantities people actually use when they describe a colour: which colour, how strong, how bright.

• Hue: the position on the colour wheel, from 0 to 359 degrees. It decides whether something is red, green or blue.
• Saturation: how strong the colour is, from grey to pure. Brightness: how light it is, from black to fully lit.
• The sliders start neither in the middle nor on your last colour, but on a decoy colour drawn for the purpose. It sits at least 60 degrees away from the target hue and is clearly different in other respects too: the area visibly starts somewhere else and gives you no clue.
• The target colour is never near grey and never near black. Saturation and brightness have a lower bound, because where both approach zero the hue no longer matters and the task would not be hard, just arbitrary.

Scoring

Only the distance between your colour and the target counts, converted into 0 to 100 points per round. The calculation happens on the server: your browser sends three slider values, everything else is produced there.

• What is measured is not the arithmetic distance but the perceived one. Two equally close attempts therefore score the same, whatever region of colour space they sit in. With a simpler measure, blues in particular felt like a lottery.
• The full 100 exists only below the threshold of perception, that is, where the difference could not be seen even side by side. Everything above falls off along a fixed curve.
• All three sliders count. A perfectly matched hue does not save a round in which saturation and brightness are off.
• Time does not count. Whether you spend two seconds or two minutes on the sliders changes nothing.
• In five matches the five round scores are added up, 500 being the maximum.
• Every round comes with a verdict. It follows the score and is picked at random within its class, so the same performance does not always get the same sentence.

Streak, level and experience

• You can play without an account. Your rounds are still saved, but they belong to nobody.
• Signed in, every finished game counts a tenth of its points as experience: 0 to 10 for a single round, 0 to 50 for five matches. Rounding down happens per game, so the display matches the result you just saw.
• The first level up costs 20 experience points, the second 40. After that the price grows ever more slowly and approaches 500: the step from level 10 to 11 costs 173, the one from 20 to 21 costs 286.
• The flame burns on every day you played. A day runs from midnight to midnight German time, and if you last played yesterday your streak survives and you can continue it today.
• The streak applies to Color only: playing Calculator today does not feed your Color streak. Experience, by contrast, is a single number across all games.

History and replay

Signed in, every saved game appears in your history, and you can watch it again.

• What is recorded is not just the result but every single slider action: every drag, every key press and every direct click on a bar.
• The replay runs through the same playing area as a real game, with the same countdown and the same memorising time. Only the sliders move from the recording instead of from your hand.
• What becomes visible is how you searched: whether you set the hue first, how often you went back, and where you settled in the end.

Tips

• Do not memorise "blue", memorise a direction: towards green or towards violet. A name is too coarse to mix from.
• Set the hue first, saturation and brightness after. The other way round, the impression shifts with every correction.
• Watch the brightness. It is the axis most likely to be off, because a bright screen looks different from the memory of it.
• Do not let the starting colour pull you in. It is deliberately far from the original, and moving only a little away from it leaves you far away too.
• Start with "easy". You get five seconds instead of two, and judging is milder while you learn how the sliders respond.
• Play in the same light. A shade you matched in daylight looks different on the same screen in the evening.