Amplitude is the maximum displacement of a periodic function from its central or equilibrium value. For a sine wave, it controls how tall or wide the oscillation appears. section 9.3.1 section 12.3.2
Scale a sine or cosine result to control the motion’s size:
- Multiply sin(θ) by a value greater than 1 to increase amplitude. section 9.3.1
- Multiply sin(θ) by a value between 0 and 1 to decrease amplitude. section 9.3.1
- Keep amplitude separate from frequency: amplitude changes displacement, while frequency changes how quickly the wave cycles. section 9.3.1
Wave-shaped text
Split text into individual spans, then apply `offset = amplitude * Math.sin(frequency * index)` to each letter. With an amplitude of 30, the letters receive vertical offsets up to 30 pixels in either direction. section 9.3.1
Pendulum animation
Set `const amplitude = 45` and calculate `rotation = amplitude * Math.sin(angle)`. Applying that value to a CSS rotate transform makes an element swing through a 45-degree range on either side of its center. section 12.3.2
offset = a * sin(f * θ)
Use the compact wave equation to see amplitude, frequency, and angle combined in one calculation. section 9.3.1
