%% -*- mode: octave -*-
%%
%% *SpHEAR Project
%%
%% sphear_bf_plot_polar_response: plot polar response of B format components
%%
%% usage:
%%   sphear_bf_plot_polar_response(B, frefmin, frefmax, fmin, fmax, Noct, Nfft, Fs, cardioid = 0)
%%
%% B: B format signal
%% frefmin, frefmax: reference frequencies for power reference
%% fmin, fmax: lower and upper frequency limits
%% Noct: width of frequency ranges in fractions of an octave, this
%%       will be changed slightly so that the frequency range is
%%       covered by equally spaced frequency bands
%% Nfft: FFT size
%% Fs: sampling rate
%%
%% optional:
%%
%% cardioid: 1 -> replace Z component by a virtual cardioid pointing forward
%%
%% Copyright 2016-2017, Fernando Lopez-Lezcano, All Rights Reserved
%% nando@ccrma.stanford.edu
%%
%%  This program is free software: you can redistribute it and/or modify
%%  it under the terms of the GNU General Public License as published by
%%  the Free Software Foundation, either version 3 of the License, or
%%  (at your option) any later version.
%%
%%  This program is distributed in the hope that it will be useful,
%%  but WITHOUT ANY WARRANTY; without even the implied warranty of
%%  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%%  GNU General Public License for more details.
%%
%%  You should have received a copy of the GNU General Public License
%%  along with this program.  If not, see <http://www.gnu.org/licenses/>.

function sphear_bf_plot_polar_response(B, frefmin, frefmax, fmin, fmax, Noct, Nfft, Fs, cardioid = 0)

  %% color plot
  copt = '-color';
  cext = "_color";

  plotz = 0;
  
  %% calculate number of frequency bands spaced Noct
  n = floor(log(fmax/fmin)/log(2^(1/Noct)));
  %% adjust width of band so they fit exactly in frequency range
  N = log(2)/(log(fmax/fmin)/n);
  printf("%d frequency bands, %f bands per octave\n", n, N);

  %% first center frequency
  fcmin = fmin * 2^(1/(N * 2));
  %% all center and edge frequencies
  fc = fcmin * 2.^((0:n - 1)/N)';
  fe = fmin * 2.^((0:n)/N)';

  %% normalize amplitude with respect to W between 600 and 1200 Hz
  ref = sphear_signal_power(B, Fs, frefmin, frefmax, Nfft);
  norm = mean(ref(:,1));
  
  f = figure;

  idx = 1;
  for i = (1:size(fc))
    printf("fc = %d\n", fc(i));
    BP = sphear_signal_power(B, Fs, fe(i), fe(i + 1), Nfft, cardioid) / norm;
    sphear_bf_plot(BP, fe(i), fe(i + 1), 1.25, cardioid);
    idx = idx + 1;
  end

  %% print(f, '-deps','-tight',copt,["figures/sphear_cardioid_polar.eps"]);

end