What a curve actually maps
Picture a graph. Along the bottom is how far the stick is pushed, from the edge of the deadzone (0) to full travel (1). Up the side is what is sent to the game, from nothing to full output. A curve is the line between them.
- Linear is a straight diagonal: output grows in proportion to the push.
- Slow-start curves (often called exponential or quadratic) stay low through the first part of the travel and climb steeply at the end. Small movements become finer; large ones still reach full speed.
- S-shaped curves add a fast middle between a fine centre and a controlled edge.
Why the centre matters most
Most aiming happens in the first third of the stick's travel: tracking a moving target, settling the crosshair, correcting by a few pixels. The shape of the curve there decides how precisely you can make those movements. The shape near the edge decides how fast you can turn. Every curve is a trade between the two, and the right balance depends on the game's sensitivity and on your hands.
Curves stack
Most games apply a response curve of their own, sometimes under a name like “response curve”, “aim response” or “input curve”. A curve shaped in your controller software arrives at the game, and the game's curve is applied on top. Two curves on top of each other are hard to reason about. If the game offers a linear option, using it there leaves the shaping to one place.
Custom curves: points, and what happens between them
A custom curve is a handful of points you place, with the software drawing a line through them. How it draws that line matters more than it sounds.
Straight segments between the points are predictable but have corners, where the response changes abruptly. A smooth line feels more natural, but an ordinary smooth curve through points can bulge past them: it can rise above the next point and come back down, which means pushing the stick further briefly gives you less output. A monotone interpolation is smooth and never does that — more push always means at least as much output.
A separate curve for aiming down sights
Many shooters change sensitivity when you aim down sights, and what you do with the stick changes too: less turning, more fine tracking. A second curve that takes over only while you aim lets each job have its own shape instead of one compromise.
How Coda handles curves
Each stick in Coda has a curve, picked from Linear (the default), Quadratic, Enhanced, Enhanced +, Enhanced Pro, Coda, or Custom. The curve shapes the travel between the deadzone and the max zone, so the deadzone settings come first.
- The curve editor opens on whichever curve is set, built-in or custom, and lets you start from any built-in shape.
- A custom curve takes up to ten points between the fixed ends. Interpolation is Smooth, which is monotone and never overshoots a point, or Linear.
- The curve is calculated exactly on every sample rather than looked up in a table.
- While the editor is open, changes apply to the controller live, so you feel each one in your hands before you keep it, and can compare the edited curve with the original.
- Switch curve while aiming gives aiming down sights its own curve, active while any of up to six buttons or triggers you choose is held.
- Any curve can be copied as a short code and pasted into another profile, or sent to someone else.
A method for finding your curve
- Set the deadzones first, and the game's curve to linear if it has one.
- Start from linear and play long enough to know what bothers you.
- If small corrections overshoot, lower the curve near the centre. If turning feels slow, raise it near the edge.
- Move one point at a time, and test in the same practice situation each time.
- Keep the code of a curve you liked before you change it.