Turn four design numbers into an easing curve like the ones in design tools

Designers hand over a curve as four numbers from a drawing tool, but using them for time needs more than plugging them in, since the curve is described sideways. Here is how to read it correctly for any moment, even for steep curves where the usual shortcut fails.

Why this works

Design tools describe a curve by where it is steered at the start and the end, but they plot progress against a hidden helper, not against time. To read the value at a given moment, you first find which helper value gives that moment.

When not to use it

Skip it when a ready curve already feels right, or for motion that should react to the player, like a drag or a throw. A curve with a fixed duration cannot take over a speed it did not start with; use a spring there.

In the full entry

• What to build, step by step
• Starting values and the reason for each
• 3 common mistakes and the fix
• 29 lines of example code with 4 checks that pass
• How your AI shows you that it works

Say this to your AI

Use the Spielerando entry "Turn four design numbers into an easing curve like the ones in design tools" (read_entry custom-easing-curve-from-four-numbers) in my game. Build it step by step, and show me how you checked that it works.

Or skip this and connect the MCP: your AI then finds all of this by itself.Connect the MCP