Scoring
How copy² is scored
Nobody judges your drawing. Two measurements do, and neither of them has taste.
The two measurements
Every figure is worth 5.00, and how much of that you keep is how similar your drawing is — there is no clock in the score at all. Take the full time; it costs nothing.
Your drawing and the reference are both reduced to a 64×64 grid, normalised so that position and size don't matter but proportion does. Then:
Symmetric Chamfer distance — for every line in one drawing, how far it is from the nearest line in the other, measured in both directions. One direction catches lines you invented; the other catches lines you left out.
Ink coverage — how much of the grid each drawing fills. Chamfer distance alone is trivially cheatable: a dense scribble sits close to every line of the original and has every line of the original close to it. The first version of this scored a destroyed copy 0.78 out of 1. Coverage closes that hole, and catches the opposite failure of drawing almost nothing.
What the numbers look like
| What you drew | Typical score |
|---|---|
| A careful freehand copy | 3.2 – 4.3 |
| A rushed one | 2.0 – 3.0 |
| Confidently the wrong figure | around 1.3 |
| A scribble, or an empty canvas | near 0 |
| Round | Figures | Seconds each | Maximum |
|---|---|---|---|
| Easy | 6 | 9 | 30.00 |
| Hard | 8 | 7 | 40.00 |
| Brutal | 10 | 5 | 50.00 |
Brutal shows you the reference mirrored and scores you against the original, so the flip has to happen in your head.
Why the deck is drawn, not photographed
All thirty reference figures are built from primitives — arcs, ovals, stars, spirals, zigzags — rather than scanned. That keeps them sharp at any size and keeps the thing you are measured against fair, which a photograph of somebody's doodle would not be. No two cards in the deck score highly against each other, which is how one lollipop tree became a pine.
copy² is the one game with no timing component in its score at all: it is a pure function of the figure and what you drew, so the server can recompute it completely.
Play copy²