A small native Odin + raylib application for building, listening to, and visualizing sums of sinusoidal signals.

• Up to 8 sinusoidal components.
• Exact editable frequencies from 1 Hz to 20 kHz.
• Per-component amplitude, phase, mute, and removal.
• Real-time mono 48 kHz floating-point audio.
• Time-domain view of every component and their sum.
• Component spectrum.
• Optional automatic headroom to avoid hard clipping.
• Pure 4:5:6 and 12-EDO C-major presets.
• Resizable native window.

Install Odin:

sudo pacman -S odin

The project imports vendor:raylib, so installing the separate raylib package is normally unnecessary.

Run directly:

odin run . -o:speed

Build an executable:

odin build . -out:sine-lab -o:speed
./sine-lab

On Hyprland, raylib's normal Linux desktop build generally opens through XWayland. If no window appears, verify that XWayland is enabled.

• Click a frequency field, type a value, and press Enter.

• Escape cancels frequency editing.

• The - and + buttons change frequency by 1 Hz.

• Hold Shift while clicking them to change it by 10 Hz.

• Audio ON/OFF only gates output; the stream remains alive.

• Reset phase restarts all oscillator running phases together.

• Auto headroom applies

  gain = min(1, 0.95 / sum(amplitudes))
  

  before master volume, then the final PCM sample is clamped to [-1, 1].

The component spectrum is intentionally not an FFT: these are analytically defined sinusoids, so their frequencies and amplitudes are already known exactly. Drawing stems at those frequencies is more accurate than estimating them from a finite FFT window.

The program searches these paths in order:

1. ./ui-font.ttf
2. /usr/share/fonts/noto/NotoSans-Regular.ttf
3. /usr/share/fonts/TTF/DejaVuSans.ttf
4. /usr/share/fonts/liberation/LiberationSans-Regular.ttf
5. /usr/share/fonts/gnu-free/FreeSans.ttf

On Arch, the default choice is Noto Sans when noto-fonts is installed:

sudo pacman -S noto-fonts

To use any other TrueType font without changing the source, copy or symlink it as ui-font.ttf in the directory from which you launch the application:

ln -s /path/to/MyFont-Regular.ttf ui-font.ttf
odin run . -o:speed

The font file is loaded at runtime; it is not embedded in the executable.