%
% nvolOut = ECC_animation_2x2( flRadius, imDim, flPxShiftMax, flDuration )
% -------------------------------------------------------------------------
%
%   Creates a set of circle with center-surround frames of a movie for 
%   a "directional edge contrast motion" illusion.
%
% USAGE:    nimOut = Edge_contrast_circle_animation( 25, 100, 45, 90, 36, 1.0 );
%
% INPUT:
%
%   flRadius        - Circle radius, in pixels.
%   imDim           - One dimension of the resulting square image, in
%                     pixels, unless this dimension will clip the circle image.
%   nAngle          - Direction of apparent motion, in degrees.
%   nPhaseStart     - First frame phase, in degrees.
%   flPxShiftMax    - Proportional to maximum edge shift. Also set appropriate
%                     animation frame rate (see hardcoded nFrameRate).
%   flDuration      - Duration of one cycle of the animation, in pixels/second. 
%                     (For flSpeedPxpS = 24 and the hardcoded nFrameRate = 24, 
%                     the valid values include [ 1/12, 1/8, 1/6, 1/4, 1/3, 1/2, 15/24, 1, 3/2, 5/3, 15/8, 5/2, 15/4, 5 ]
%                     constrained by the condition: 360/(flDuration*nFrameRate)is integral.
%
% HARDCODED (immediately below function declaration):
%
%   strFilestem       - File stem naming of output file.
%   strFileFmt        - File extension that specifies the image format,
%                       e.g.'.png', '.tif', '.jpg', etc.
%   nOverSample       - [1, 16] Flat aperture oversampling rate.
%   nFrameRate        - Expected animation frame rate.
%
%   bShowResult       - [0, 1] Display final image (only last frame).
%   bWriteResult      - [0, 1] Write image to file.
%
% RETURN VALUES:
%
%   nvolOut    - Grayscale [ imDim x imDim x #frames ] image array of 8-bit integers
%                (uint8).
%
% OUTPUT:
%
%	If bWriteResult == 1, writes grayscale image to current directory.
%
% FUNCTION CALLS and DEPENDENCIES: 
%
%	Edge_contrast_circle.m
%   write_Space_volume.m
%
%
% Mark Dow,             May 5, 2008
% Mark Dow, modified    May 6, 2008 (added phase and maximum shift)
%
%
%   TERMS FOR USE: There are no restrictions on the use of this code, 
%                  auxilliary code and other required resources. Claiming 
%                  to be the originator, explicitly or implicitly, is bad  
%                  karma. A link (if appropriate), a note to dow[at]uoregon.edu, 
%                  and credit are appreciated but not required.
%

function nvolOut = ECC_animation_2x2( flRadius, imDim, flPxShiftMax, flDuration )

% flAngle      = nAngle*pi/180;
% flPhaseStart = nPhaseStart*pi/180;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% hardcoded parameters
%strStem = 'Circles-2x2';
strStem = 'test';

%dir   = [  45 135 225 315 ];   % radial opposite
%strStem = 'RO1';
% dir   = [ 45 315 225 135 ];   % radial in
% strStem = 'RO2';
dir   = [ 135 45 315 225 ];   % CCW
strStem = [ strStem '-CW' ];
% dir   = [ 315 225 135  45 ];   % CCW
% strStem = [ strStem '-CCW' ];

% phase = [   0  180  0  180 ];   % alternating phase
% strStem = [ strStem '-PA' ];

phase = [   0  0  0  0 ];   % no phase difference
strStem = [ strStem '-P0' ];
% phase = [   30  30  30  30 ];   % no phase difference
% strStem = [ strStem '-P30' ];
% phase = [   45  45  45  45 ];   % no phase difference
% strStem = [ strStem '-P45' ];
% phase = [   90  90  90  90 ];   % no phase difference
% strStem = [ strStem '-P90' ];

% phase = [  270 180 90 0  ];   % cyclic CCW
% strStem = [ strStem '-PCCW' ];

% phase = [   0  90 180 270 ];   % cyclic CW
% strStem = [ strStem '-PCW' ];


strStem = [ strStem '-gray' ];

strFilestem   = [ strStem '-' num2str(flRadius) '_' num2str(imDim) '_' num2str(flPxShiftMax) '_' num2str(flDuration) ]
nOverSample   = 5;
nFrameRate    = 24;

% hardcoded parameters
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

nvolOut( 1:2*imDim, flDuration*24, 1:2*imDim ) = 127;
%flPxShiftMax*flDuration

nimQquad = Edge_contrast_circle_animation( flRadius, imDim, dir(1), phase(1), flPxShiftMax, flDuration );
% size(nimQquad)
% size(nvolOut)
 szQquad = size( nimQquad );
 number_of_frames = szQquad(2)
% To Do: Warn when the sub-image must be clipped.
% szQquad(1)/2 - imDim/2 + 1
% szQquad(1)/2 - imDim/2 + imDim
% szQquad(3)/2 - imDim/2 + 1
% szQquad(3)/2 - imDim/2 + imDim
nvolOut( 1:imDim, :, 1:imDim ) = nimQquad( szQquad(1)/2 - imDim/2 + 1 : szQquad(1)/2 - imDim/2 + imDim, :, szQquad(3)/2 - imDim/2 + 1 : szQquad(3)/2 - imDim/2 + imDim );

nimQquad = Edge_contrast_circle_animation( flRadius, imDim, dir(2), phase(2), flPxShiftMax, flDuration );
nvolOut( imDim + 1:2*imDim, :, 1:imDim ) = nimQquad( szQquad(1)/2 - imDim/2 + 1 : szQquad(1)/2 - imDim/2 + imDim, :, szQquad(3)/2 - imDim/2 + 1 : szQquad(3)/2 - imDim/2 + imDim );

nimQquad = Edge_contrast_circle_animation( flRadius, imDim, dir(3), phase(3), flPxShiftMax, flDuration );
nvolOut( imDim + 1:2*imDim, :, imDim + 1:2*imDim ) = nimQquad( szQquad(1)/2 - imDim/2 + 1 : szQquad(1)/2 - imDim/2 + imDim, :, szQquad(3)/2 - imDim/2 + 1 : szQquad(3)/2 - imDim/2 + imDim );

nimQquad = Edge_contrast_circle_animation( flRadius, imDim, dir(4), phase(4), flPxShiftMax, flDuration );
nvolOut( 1:imDim, :, imDim + 1:2*imDim ) = nimQquad( szQquad(1)/2 - imDim/2 + 1 : szQquad(1)/2 - imDim/2 + imDim, :, szQquad(3)/2 - imDim/2 + 1 : szQquad(3)/2 - imDim/2 + imDim );


write_Space_volume( nvolOut, [ strFilestem ] );