BUILD: Minor comment update in Cmake files

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
BUILD: No longer using Microsoft specifics extension in library build

No extension was used but this flag ensure that we cannot use them with
msvc.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
FILTER: Fixed typo in assert

The "frequency" was asserted two times instead of one assert on frequency,
and one on the resonance.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
FILTER: Now checking that the filter frequency is within some range

Due to some accuracy issues in our filter, we cannot allow too high
or too low frequencies, even if they are within Nyquist range.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
SYNTHESIZER: Added a filter object

This wraps the internal low pass filter.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
FILTERS: Added a factory

Mimicking generators, we are using a filter factory - it may be useless
after all but for now this will suffice.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
SYNTHESIZER: Added filter-related parameters

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
SYNTHESIZER: Added the filter in the audio path

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
TESTS: Added a debug utility file

To be included and used for debugging purpose only!

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
TESTS: More readable filter test

By using separated variables for input/output this test gets more readable
(and debuggable).

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
TESTS: Added a test for filters in "almost passthrough" configuration

This use extreme values for the filter configuration and checks that the
signal does not get too heavily modified.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
TESTS: Less restrictive synthesizer tests

Now that we ae using a filter in the synthesizer, and since ringing
could occur, we have to be less strict on a few click detection tests.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
IMPLEMENTATION: Added all filter-related widgets

This is for testing purpose only, we need a widget factory/manager.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
SCRIPTS: Added an utility script for extracting test/debug data

This may be used with all fles generated with functions in debug.h

Signed-off-by: Gama <misept.dieseneuf@gmail.com>
AUDIO: Added a Reaper test project

This allows a fast and easy test setup.

Signed-off-by: Gama <misept.dieseneuf@gmail.com>