Yammer

Audio visualizer thing in guile scheme

Build

guile-sdl2, fftw

You need to compile the yammer.c file because it has wrappers around fftw functions.

gcc -shared yammer.c -o libyammer.so -Wall -Wextra -Werror -fPIC -shared -lfftw3 -lm -O3 -ggdb

Copy config.example.scm to config.scm

Below is a list of values and what they do

fifo-file: The MPD fifo
fps: Self explanatory
resolution: Pixel width of bars
scale: Bar height multiplier
color: Bar color
bgcolor: Background color
queue-size: The size of the queue (minimum of 1), delays displaying bars by queue-size frames. Useful if desync is noticed
fft: Whether or not to perform a fourier transform to show frequencies (like spectrum mode in most other visualizers)
fft-interpolation: Number of points to interpolate between fft values. <1 means disable
smoothing: Smoothing mode. Possible values are:
- #f: No smoothing or interpolation. Disregards fft-interpolation
- 'none: No smoothing
- 'moving-average: Moving average
- 'exponential: Simple (basic) exponential smoothing
moving-average-block-size: Size of the moving average window. Higher is smoother.
exponential-factor: Exponential smoothing factor, lower is more smooth.
exponential-init-factor: The first value of the exponentially smoothed list is multiplied by this

Either install libyammer.so and yammer.h to their respective systemwide locations, or do the following:

export LD_LIBRARY_PATH=.

Then, run yammer.

guile -L . yammer.scm

Sometimes the read gets misaligned and just becomes noise
When MPD is paused or the program is sleeping for the next frame, the UI doesn't update so you can't exit
The surface can't be transparent