function varargout = singlepatch(varargin)

%SINGLEPATCH Concatenate patches to be plotted as one

%

% [xp, yp, zp, ...] = singlepatch(x, y, z, ...)

%

% Concatenates uneven vectors of x and y coordinates by replicating the

% last point in each polygon.  This allows patches with different numbers

% of vertices to be plotted as one, which is often much, much more

% efficient than plotting lots of individual patches.  

%

% Input variables:

%

%   x:   cell array, with each cell holding a vector of coordinates

%        associates with a single patch.  The input variables must all be

%        of the same size, and usually will correspond to x, y, z, and c

%        data for the patches.

%

% Output variables:

%

%   xp:  m x n array of coordinates, where m is the maximum length of the

%        vectors in x and n is numel(x).  

% Copyright 2015 Kelly Kearney

if nargin ~= nargout

    error('Must supply the same number of input variables as output variables');

end

nv = nargin;

vars = varargin;

sz = cellfun(@size, vars{1}(:), 'uni', 0);

sz = cat(1, sz{:});

if all(sz(:,1) == 1)

    for ii = 1:nv

        vars{ii} = catuneven(1, NaN, vars{ii}{:})';

    end

%     x = catuneven(1, NaN, x{:})';

%     y = catuneven(1, NaN, y{:})';

elseif all(sz(:,2) == 1)

    for ii = 1:nv

        vars{ii} = catuneven(2, NaN, vars{ii}{:});

    end

%     x = catuneven(2, NaN, x{:});

%     y = catuneven(2, NaN, y{:});

else

    error('Inputs must be cell arrays of vectors');

end

[ii,jj] = find(isnan(vars{1}));

ind = accumarray(jj, ii, [size(vars{1},2) 1], @min); 

ij1 = [ii jj];

ij2 = [ind(jj)-1 jj];

idx1 = sub2ind(size(vars{1}), ij1(:,1), ij1(:,2));

idx2 = sub2ind(size(vars{1}), ij2(:,1), ij2(:,2));

for ii = 1:nv

    vars{ii}(idx1) = vars{ii}(idx2);

end

varargout = vars;