root/trunk/axesZoom.m

function axesZoom(obj, evd, tag, factor)
% Zoom in axes
%
% AXESZOOM(OBJ, EVD, TAG, FACTOR)
% Zoom in axes designed by TAG. If FACTOR is given, it is applied to
% correct the coordinates. The center is the position of the mouse when
% called.If not, coordinates are supposed to be present in the UserData
% part, in a struct coords.xlim
%                         .ylim
%
% Typical use is associated with a context menu. The outlier module
% provides a good example.
%
% This is part of a generic tool for zooming in plots.
% See axesZoomRect.m
%
% obj:    hObject                                                  [object]
% evd:    event data                                               [string]
% tag:    tag of the concenred axes                                [string]
% factor: zoom factor applied                                      [double]

% Copyright 2006-2007 INRIA
%
% This file is part of WellReader
% 
% WellReader is free software: you can redistribute it and/or modify
% it under the terms of the GNU Lesser General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% WellReader 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 Lesser General Public License for more details.
%
% You should have received a copy of the GNU Lesser General Public License
% along with WellReader.  If not, see <http://www.gnu.org/licenses/>.

ax = findobj('Tag', tag);
if nargin == 4 % factor given
    xlim = get(ax, 'XLim');
    ylim = get(ax, 'YLim');
    center = get(ax, 'CurrentPoint');
    xcenter = center(1,1);
    ycenter = center(1,2);
    xwidth = (xlim(2) - xlim(1)) / (2 * factor);
    set(ax, 'XLim', [xcenter-xwidth, xcenter+xwidth]);
    ywidth = (ylim(2) - ylim(1)) / (2 * factor);
    set(ax, 'YLim', [ycenter-ywidth, ycenter+ywidth]);
else
    coords = get(ax, 'UserData');
    set(ax, 'XLim', coords.xlim);
    set(ax, 'YLim', coords.ylim);
end

end