%FRACGRX is a subroutine of the driving program FRACTORY.  It
%generates the graphics screen user interface which shows the
%square(paralellagram) representations of the IFS's, and allows
%the user to manipulate the IFS parameters visually.

%Setup initial data
Gscr=figure;
set(Gscr,'Position',[395 100 535 560]);
set(Gscr,'Units','normalized');
Gaxes = get(Gscr,'CurrentAxes');
axpos=[.1 .1 .85 .85];
set(Gaxes,'NextPlot','add',...
    'Position',axpos,...
    'XLim',[0 1],...
    'YLim',[0 1]);
bttog=0;
clear inlist

curpts(1) = uicontrol(Gscr,...
    'Style','push',...
    'Units','normalized',...
    'Position',[.08 .93 .04 .04],...
    'String','X');
curpts(2) = uicontrol(Gscr,...
    'Style','push',...
    'Units','normalized',...
    'Position',[.08 .08 .04 .04],...
    'String','Y');
curpts(3) = uicontrol(Gscr,...
    'Style','push',...
    'Units','normalized',...
    'Position',[.93 .08 .04 .04],...
    'String','Z');
curpts(4) = uicontrol(Gscr,...
    'Style','push',...
    'Units','normalized',...
    'Position',[.505 .505 .04 .04]);

curpos='[(get(Gscr,''CurrentPoint'')-[.02 .02]) .04 .04]';
MtnAct = 'set(curpts(n_pt),''Position'',eval(curpos))';
FollowOn=['set(Gscr,''WindowButtonMotionFcn'',MtnAct);',...
        'set(Gscr,''WindowButtonUpFcn'',StpAct);',...
        'bttog=1;',...
        'clear inlist,',...
        'curdat(11)=n_pt;'];
FollowOff='set(Gscr,''WindowButtonMotionFcn'','' '')';
StpAct = ['eval(FollowOff),',...
    'set(Gscr,''WindowButtonUpFcn'',''inbox'');',...
    'newv=get(curpts(n_pt),''Position'');',...
    'newv=chgcrd(newv(1:2),axpos,0)+[.02 ; .02];',...
    'if n_pt==4,',...
      'newv=curdat(3:4)+(newv-(curdat(1:2)+curdat(5:6))/2);',...
    'end,',...
    'bttog=0;',...
    'updatecd'];

for nn=1:4
  set(curpts(nn),'CallBack',[...
      'if bttog==0,',...
          'n_pt=',num2str(nn),';',...
          'eval(FollowOn),',...
      'else,',...
          'eval(StpAct);',...
      'end']);
end

set(Gscr,'WindowButtonUpFcn','inbox');

axes(Gaxes);
fcns(1)=line(curdat([7 1 3 5 7]),curdat([8 2 4 6 8]));
set(fcns(1),'Color','m');