function h=m_ruler(posx,posy,varargin);% M_RULER Draws a distance scalebar for a map%   M_RULER([X1 X2],Y1) draws a horizontal scale bar between the%   normalized coordinates (X1,Y1) and (X2,Y1) where both X/Y are%   in the range 0 to 1.  %   M_RULER(X1,[Y1 Y2]) draws a vertical scalebar%   M_RULER(...,NINTS) draws the scalebar with NINTS intervals%   if NINTS is a scalar (default 4).  Distances of each interval are %   chosen to be 'nice'. If NINTS is a vector it is understood to be%   the distances to be used (in meters)%%   M_SCALEBAR(....,'parameter','value',...) lets you specify%   extra parameter/value pairs in the usual handle-graphics way.%   'color' and 'fontsize' are probably the most useful, 'tickdir'%   'in' and 'out' chooses between different styles.%%   Probably BEST to call this AFTER M_GRID otherwise placement might%   seem a bit odd.%% WARNING - the scalebar is probably not useful for any global%           (i.e. whole-world) or even a significant-part-of-the-globe%           map, but I won't stop you using it. Caveat user!% R. Pawlowicz rich@eos.ubc.ca  8/Nov/2006nints=4;fixticks=0;if length(varargin)>0, if isnumeric(varargin{1}),   nints=varargin{1};   varargin=varargin(2:end);   fixticks=1;  end;end;     gcolor='k';glinestyle='-';glinewidth=3;gfontsize=get(gca,'fontsize');gfontname=get(gca,'fontname');gticklen=get(gca,'ticklen'); gticklen=gticklen(1); gtickdir=get(gca,'tickdir');   % Parse parameter list for options. I really should do some% error checking here, but...k=1;while k<=length(varargin),  switch lower(varargin{k}(1:3)),    case 'col',      gcolor=varargin{k+1};    case 'lin',      switch lower(varargin{k}(1:5)),         case 'linew',           glinewidth=varargin{k+1};         case 'lines',           glinestyle=varargin{k+1};      end;    case 'fon',       switch lower(varargin{k}(1:5)),         case 'fonts',           gfontsize=varargin{k+1};         case 'fontn',           gfontname=varargin{k+1};       end;    case 'tic',       switch lower(varargin{k}(1:5)),         case 'tickl',           gticklen=varargin{k+1};         case 'tickd',           gtickdir=varargin{k+1};       end;    case {'get','usa'},      disp('      ''ticklen'',value');      disp('      ''tickdir'',( ''in'' | ''out'' )');      disp('      ''color'',colorspec');      disp('      ''linewidth'', value');      disp('      ''linestyle'', ( linespec | ''none'' )');      disp('      ''fontsize'',value');      disp('      ''fontname'',name');       return;    case 'set',      disp(['      ticklen = ' num2str(gticklen)]);      disp(['      tickdir = ' gtickdir]);       disp(['      color = ' gcolor]);      disp(['      linewidth = ' num2str(glinewidth)]);      disp(['      linestyle = ' glinestyle]);      disp(['      fontsize = ' num2str(gfontsize)]);      disp(['      fontname = ' gfontname]);       return;  end;  k=k+2;end;      % Need earth radius, in m.erad=6378137; %m (from WGS-84)if  ( length(posx)==2 & length(posy)==1),  posy=[posy posy];  horiz=1;elseif  ( length(posx)==1 & length(posy)==2),  posx=[posx posx];  horiz=0;end;xlm=get(gca,'xlim');ylm=get(gca,'ylim');% Get into screen coordsposx=xlm(1) + posx*diff(xlm);posy=ylm(1) + posy*diff(ylm);if diff(xlm)>10, % we are probably already in meters, i.e. UTM   scfac=1;else  scfac=erad;end;distance=(diff(posx)+diff(posy))*scfac;niceints=[ 1      2      5  ...           10     20     50 ...	   100    200    500  ...	   1000   2000   5000  ...	   10000  20000  50000  ...	   100000 200000 500000 ...	   1000000 2000000 5000000 ];	    	   if length(nints)==1,	    exactint=distance/(nints);  [dun,I]=min(abs(niceints-exactint));   if ~fixticks,    nints=fix(distance/niceints(I));  end;  dist=[0:nints]*niceints(I);else  dist=(nints-nints(1));  nints=length(dist)-1;end;if max(log10(dist(2:end)))>=3,   numfac=1000;else   numfac=1;end;      if horiz,    if strcmp(gtickdir,'in'),    line(posx(1)+[0 dist(end)/scfac],posy(1)+[0 0],'color',gcolor,'linewi',glinewidth,'linest',glinestyle,...	 'clip','off','tag','m_ruler_x');    line(posx(1)+[dist;dist]/scfac,posy(1)+diff(ylm)*gticklen*[-1;1]*ones(1,nints+1),...	 'color',gcolor,'linewi',glinewidth/3,'linest',glinestyle,...	 'clip','off','tag','m_ruler_y');  else       patch(posx(1)+[dist(1:end-1);dist(1:end-1);dist(2:end);dist(2:end)]/scfac,...           posy(1)+diff(ylm)*gticklen*[-1;1;1;-1]*ones(1,nints),...	   repmat(bitmax  ,4,nints),...           reshape(rem(rem(0:nints*3-1,nints),2)==0,1,nints,3),...	 'linewi',glinewidth/3,'linest',glinestyle,...         'clip','off','tag','m_ruler');  end;     if nints>1,    for k=1:nints,      text(posx(1)+dist(k)/scfac,posy(1)-diff(ylm)*gticklen*2,sprintf('%d',dist(k)/numfac), ...          'fontsize',gfontsize,'fontname',gfontname,...         'vertical','top','horiz','center','tag','m_ruler_label');    end;    text(posx(1)+dist(nints+1)/scfac,posy(1)-diff(ylm)*gticklen*2,sprintf('%d km',dist(end)/numfac),...          'fontsize',gfontsize,'fontname',gfontname,...          'vertical','top','horiz','center','tag','m_ruler_label');  else     text(posx(1)+mean(dist)/scfac,posy(1)-diff(ylm)*gticklen*2,sprintf('%d km',dist(end)/numfac),...          'fontsize',gfontsize,'fontname',gfontname,...          'vertical','top','horiz','center','tag','m_ruler_label');  end;  else,  if strcmp(gtickdir,'in'),    line(posx(1)+[0 0],posy(1)+[0 dist(end)/scfac],'color',gcolor,'linewi',glinewidth,'linest',glinestyle,...	 'clip','off','tag','m_scalebar_x');    line(posx(1)+diff(xlm)*gticklen*[-1;1]*ones(1,nints+1),posy(1)+[dist;dist]/scfac,...	 'color',gcolor,'linewi',glinewidth/3,'linest',glinestyle,...	 'clip','off','tag','m_ruler_y');  else       patch(posx(1)+diff(xlm)*gticklen*[-1;1;1;-1]*ones(1,nints),...          posy(1)+[dist(1:end-1);dist(1:end-1);dist(2:end);dist(2:end)]/scfac,...	   repmat(bitmax  ,4,nints),...           reshape(rem(rem(0:nints*3-1,nints),2)==0,1,nints,3),...	 'linewi',glinewidth/3,'linest',glinestyle,...         'clip','off','tag','m_ruler');  end;  if nints>1,    for k=1:nints,      text(posx(1)+diff(xlm)*gticklen*2,posy(1)+dist(k)/scfac,sprintf('%d',dist(k)/numfac), ...          'fontsize',gfontsize,'fontname',gfontname,...         'vertical','middle','horiz','left','tag','m_ruler_label');    end;    text(posx(1)+diff(xlm)*gticklen*2,posy(1)+dist(nints+1)/scfac,sprintf('%d km',dist(end)/numfac),...          'fontsize',gfontsize,'fontname',gfontname,...          'vertical','middle','horiz','left','tag','m_ruler_label');  else      text(posx(1)+diff(xlm)*gticklen*2,posy(1)+mean(dist)/scfac,sprintf('%d km',dist(end)/numfac),...          'fontsize',gfontsize,'fontname',gfontname,...          'vertical','middle','horiz','left','tag','m_ruler_label');  end;       end;