% GIFMAKER    Simple movie on transparent background.
% (scheme package)
%
% gifmaker (action, name, Tsize, delaytime)
% -----------------------------------------
%
% Creates a transparent movie. Put this function in strategic places in
% your code to append frames one by one to a movie with transparent
% background (white = transparent). Leaves a temporary file "zzzzzz.tif" in
% the current directory.
%
% Input
% -----
% - action::string: 'init' 'loop' or 'finish'
% - name::string: name of the output-file with extension {DEFAULT:
%   'test.gif'}
% - Tsize::2-tupel: fixed size in cm [horiz. x vertical] {DEFAULT 10cm x
%   10cm}
% - delaytime::value: time between frames {DEFAULT: .1 sec}
%
% Output
% ------
%
% Example
% -------
% tree = sample_tree;
% clf; shine; axis off;
% gifmaker ('init','sample.gif',[10 5]);
% for te = 0:10:355,
%     clf; shine; axis off;
%     rtree = tree; X0 = rtree.X(1); Y0 = rtree.Y(1); Z0 = rtree.Z(1);
%     rtree = rot_tree (tran_tree (rtree),[0 te 0]);
%     rtree = tran_tree (rtree, [X0, Y0, Z0]);
%     plot_tree(rtree, [],[],[],32,'-3l');
%     xlim([-140 140]); ylim([-20 120]);
%     gifmaker ('loop','sample.gif',[10 5]);
% end
% gifmaker ('finish','sample.gif',[10 5]);
% 
% See also tprint
% Uses tprint
%
% the TREES toolbox: edit, visualize and analyze neuronal trees
% Copyright (C) 2009  Hermann Cuntz

function gifmaker (action, name, Tsize, delaytime)

global ZZZZZZ

if (nargin < 2)||isempty(name),
    name = 'test.gif';
end

if (nargin < 3)||isempty(Tsize),
    Tsize = [10 10];
end

if (nargin < 4)||isempty(delaytime),
    delaytime = .1;
end

switch action
    case 'init'
        ZZZZZZ = {};
        set (gcf, 'doublebuffer', 'on'); colormap gray(256);
    case 'loop'
        drawnow;
        tprint ('zzzzzz', '-tif', Tsize); M = imread ('zzzzzz.tif');
        ZZZZZZ {end + 1} = M(:, :, 1);
    case 'finish'
        ZZZZZZ = cat (4, ZZZZZZ{:});
        imwrite (ZZZZZZ, gray(256), name, 'gif', 'delaytime', delaytime, 'LoopCount', inf, ...
            'TransparentColor', 255, 'backgroundcolor', 255, 'DisposalMethod', 'restoreBG');
        clear ZZZZZZ
end