function newmap=mapoffset(map, c)
%MAPOFFSET Move the colormap offset

%
% Copyright (c) 1995 by Claudio Rivetti and Mark Young
% claudio@alice.uoregon.edu,    mark@alice.uoregon.edu
%

global ed_contrast MapSize

if nargin>2
  error('Too many input arguments.');
end

if nargin<1
  c=0;
end

if c<-10 | c>10
  error('Input argument must be between -10 and 10');
end

if c>0
  bc=round(MapSize*(1-c*0.1));
  ab=MapSize-bc;
  abmap=zeros(ab,3);
  for i=1:size(abmap,2)
    abmap(:,i)=abmap(:,i)+map(1,i);
  end
  bcmap=map(1:bc,:);
else
  ab=round(MapSize*(1+c*0.1));
  bc=MapSize-ab;
  bcmap=zeros(bc,3);
  if bc>0
     for i=1:size(bcmap,2)
        bcmap(:,i)=bcmap(:,i)+map(MapSize,i);
     end
  end
  abmap=map(bc+1:MapSize,:);
end


newmap=[abmap;bcmap];

return