C++ template based AudioMixer

[manicksan]

Hi Paul,
I did some changes to the AudioMixer so that is uses C++ template,
so that it can be instanced with:

AudioMixer<N> mixer; // N defines the number of inputs.

To make the code easier to maintain
I removed the AudioMixer4 class and replaced it with:
#define AudioMixer4 AudioMixer<4>

also all code is removed in Mixer.cpp and moved to
Mixer.h because templates don't work that way (compiler limitations), as described at:
https://isocpp.org/wiki/faq/template...s-defn-vs-decl

also to share the function applyGain between AudioMixer<N> and AudioAmplifier.

the changed files are at
https://github.com/manicken/Audio/blob/master/mixer.h
https://github.com/manicken/Audio/blob/master/mixer.cpp

I hope that they can be merged to the official branch so that we don't need to make special classes for every number of inputs that is needed.

[tonton81]

templates work under .tpp with compiler, you may check out the sources in FlexCAN_T4 (which has compile time and runtime object creation(user object and ISR forwarding)) and even WDT_T4. The template data must be appended to all declared functions in the tpp file, I shortened the lengths by declaring definitions in the H file to make the TPP file easier to manage

[manicksan]

ok thanks,
I have now moved all implementations to a separate tpp file which is included at the end of the h file,
just as you have done in FlexCAN.
so hopefully it's now more clean code.

new files:
https://github.com/manicken/Audio/blob/master/mixer.cpp
https://github.com/manicken/Audio/blob/master/mixer.h
https://github.com/manicken/Audio/blob/master/mixer.tpp

old files:
https://github.com/manicken/Audio/bl.../mixer.cpp.old
https://github.com/manicken/Audio/bl...er/mixer.h.old