code:
* blep etc in a module?
* osc post filter (and one pole init, slew rate, etc.) val from input? set state instead?
* audio rate optional pulse width/slope inputs?
* one pole process const input? (return also if const out)
* optimize triangle generation for constant pulse width
* API for buffer fill, scale, offset, zero, copy...?
* web examples construction/destruction
* web effect multichannel in?
* check const restrict etc.
* define BW_RESTRICT to __restrict or similar when the compiler supports it
* empty functions etc. to keep consistency and forward compatibility?
* float in [-1,1] for velocity, pitch bend, mod wheel
* should clip slope in triangle?
* fix vst3 mapped values (visible in Ableton Live) and short names
* bw_vol set volume in dB?

build system:
* make makefiles handle paths with spaces etc
* can run su on windows? (system-wide install)
* make autodependencies (.d?)
* make from... directories
* order-only prerequisites to avoid multiple make updates? (https://interrupt.memfault.com/blog/gnu-make-guidelines#order-only-prerequisites)
* clang + Ofast & bulk memory (maybe using old binaryen) - or implement memset etc.
* put common parts of Makefiles together somewhere/somehow (DRY)
* recursive make?