m_grid.m

m_map是加拿大学者编写的一个在matlab上绘地图的软件

function m_grid(varargin);
% M_GRID make a grid on a map.
%        M_GRID('parameter','value',...) with any number (or no)
%        optional parameters is used to draw a lat/long grid for a
%        previously initialized map projection.
%
%        The optional parameters allow the user
%        to control the look of the grid. These parameters are listed
%        by M_GRID('get'), with defualt parameters in M_GRID('set');
%
%        see also M_PROJ

% Rich Pawlowicz ([e-mail]) 2/Apr/1997
%
% This software is provided "as is" without warranty of any kind. But
% it's mine, so you can't sell it.
%
%  19/6/97 - set visibility of titles and so forth to 'on' (they
%            default to 'off' when axes visibility is turned off)
%  2/11/97 - for M5.1, the old way of making the patch at the bottom (i.e.
%            by rearranging the axes children) instead causes matlab to loose
%            track of titles. Try a different fix.
% 11/01/98 - Added way of making longitude lines cut off to prevent crowding near poles (you have
%            to specify a vector for allowabale latitudes for this to work).
% 16/02/98 - Made a little fudge to allow the user to fully specify grid location
%            without getting the edge points. It doesn't quite work if only *one* edge
%            point is desired....but I hope it will be OK that way.
% 19/02/98 - PC-users complain about layers getting out of order! Their fault for using
%            such an awful OS...however (with help from Eric Firing) I think I have
%            a fix.
%  7/04/98 - Another fix to grid locations to not automatically add edge points
%            (as requested by EF)
%  7/05/98 - Added 'fancy' outline box.
% 14/11/98 - Changed tag names from m_* to m_grid_*.
% 11/07/99 - Apparently fontname changing didn't work (thanks to Dave McCollum)
% 28/04/04 - Changed m_grid_color code so it works right under unix; old
%            way retained for windows (ugh).
% 16/10/05 - Kirk Ireson discovered that the way to fix those annoying 'cut-throughs'
%            in fancy_box was to add a 'large' zdata...so I've adapted his fix in
%            fancybox and fancybox2.
% 21/11/06 - added 'backcolor'
% 16/4/07  - sorted ticklabels when user-specified (prevents an odd problem near in
%            azimuthal projections).

% Note that much of the work in generating line data 
% is done by calls to the individual projections - 
% most of M_GRID is concerned with the mechanics of plotting


% These structures are initialized by m_proj()

global MAP_PROJECTION MAP_VAR_LIST

% Have to have initialized a map first

if isempty(MAP_PROJECTION),
  disp('No Map Projection initialized - call M_PROJ first!');
  return;
end;


% Otherwise we are drawing a grid!

% Set current projection to geographic
Currentmap=m_coord('set');
m_coord(MAP_PROJECTION.coordsystem.name);

% Default parameters for grid

xtick=6;
ytick=6;
xlabels=NaN;
ylabels=NaN;
gcolor='k';
gbackcolor='w'; %%get(gcf,'color');
glinestyle=':';
glinewidth=get(gca,'linewidth');
gbox='on'; 
gfontsize=get(gca,'fontsize');
gfontname=get(gca,'fontname');
gxaxisloc=get(gca,'xaxislocation'); 
gyaxisloc=get(gca,'yaxislocation');
gtickdir=get(gca,'tickdir'); 
gticklen=get(gca,'ticklen'); gticklen=gticklen(1); 
gxticklabeldir='middle';
gyticklabeldir='end';

dpatch=5; % interpolation factor for fancy grids

% 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 'box',
      gbox=varargin{k+1};
    case 'xti',
      if length(varargin{k})==5,
        xtick=sort(varargin{k+1});   % Added 'sort' here for people who put things in
      else                           % a random order near poles
        xlabels=varargin{k+1};
      end;
    case 'yti',
      if length(varargin{k})==5,
        ytick=sort(varargin{k+1});
      else
        ylabels=varargin{k+1};
      end;
    case 'xla',
      gxticklabeldir=varargin{k+1};
    case 'yla',
      gyticklabeldir=varargin{k+1};
    case 'col',
      gcolor=varargin{k+1};
    case 'bac',
      gbackcolor=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 'xax',
      gxaxisloc=varargin{k+1};
    case 'yax',
      gyaxisloc=varargin{k+1};
    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('      ''box'',( ''on'' | ''fancy'' | ''off'' )');
      disp('      ''xtick'',( num | [value1 value2 ...])');
      disp('      ''ytick'',( num | [value1 value2 ...])');
      disp('      ''xticklabels'',[label1;label2 ...]');
      disp('      ''yticklabels'',[label1;label2 ...]');
      disp('      ''xlabeldir'', ( ''middle'' | ''end'' )');
      disp('      ''ylabeldir'', ( ''end'' | ''middle'' )');
      disp('      ''ticklen'',value');
      disp('      ''tickdir'',( ''in'' | ''out'' )');
      disp('      ''color'',colorspec');
      disp('      ''backcolor'',colorspec');
      disp('      ''linewidth'', value');
      disp('      ''linestyle'', ( linespec | ''none'' )');
      disp('      ''fontsize'',value');
      disp('      ''fontname'',name');
      disp('      ''XaxisLocation'',( ''bottom'' | ''middle'' | ''top'' ) ');
      disp('      ''YaxisLocation'',( ''left'' | ''middle'' | ''right'' ) ');
      return;
    case 'set',
      disp(['      box = ' gbox]);
      disp(['      xtick = ' num2str(xtick)]);
      disp(['      ytick = ' num2str(ytick)]);
      disp(['      ticklen = ' num2str(gticklen)]);
      disp(['      tickdir = ' gtickdir]);
      disp(['      xlabeldir = ' gxticklabeldir]);
      disp(['      ylabeldir = ' gyticklabeldir]);
      disp(['      color = ' gcolor]);
      disp(['      linewidth = ' num2str(glinewidth)]);
      disp(['      linestyle = ' glinestyle]);
      disp(['      fontsize = ' num2str(gfontsize)]);
      disp(['      fontname = ' gfontname]);
      disp(['      XaxisLocation = ' gxaxisloc]);
      disp(['      YaxisLocation = ' gyaxisloc]);
      return;
  end;
  k=k+2;
end;     

if strcmp(gbox,'fancy'),
  if strcmp(MAP_VAR_LIST.rectbox,'on') | strcmp(MAP_VAR_LIST.rectbox,'circle'),
   gbox='on';
   warning([' No fancy outline with ''rectbox'' set to ''' MAP_VAR_LIST.rectbox '''']);
  end;
end;

% Draw the plot box

[X,Y]=feval(MAP_PROJECTION.routine,'box');

if strcmp(gbox,'on');
  line(X(:),Y(:),'linest','-','linewi',glinewidth,'color',gcolor,'tag','m_grid_box','clip','off');
end;

% Axes background - to defeat the inverthardcopy, I need a non-white border (the edgecolor),
% but sneakily I can set it's width to (effectively) 0 so it doesn't actually show!


% Now, putting in a white background works under linux (at least) and
% NOT under windows...I don't know about macs.
%%a=ver('matlab');  % Ver doesn't return stuff under v5!
a=version;
%%if  sscanf(a.Version,'%f') >6.0 & ~ispc,
if  sscanf(a(1:3),'%f') >6.0 & ~ispc,
  patch('xdata',X(:),'ydata',Y(:),'zdata',-bitmax*ones(size(X(:))),'facecolor',gbackcolor,...
	'edgecolor','k','linest','none','tag','m_grid_color');

else
% Now, I used to set this at a large (negative) zdata, but this didn't work for PC users,
% so now I just draw a patch...but I have decided to go back to the old
% way (above) with higher versions. Maybe the PC version works now?
% Unfortunately this kludge has some strange side-effects.

  patch('xdata',X(:),'ydata',Y(:),'facecolor',gbackcolor,...
	'edgecolor','k','linest','none','tag','m_grid_color');

  % Now I set it at the bottom of the children list so it gets drawn first (i.e. doesn't
  % cover anything)
   show=get(0, 'ShowHiddenHandles');
   set(0, 'ShowHiddenHandles', 'on');
   hh=get(gca,'children');
   htags = get(hh,'tag');
   k = strmatch('m_grid_color',htags);
   hht = hh;
   hh(k) = [];
   hh = [hh;hht(k)];
   set(gca,'children',hh);
   set(0, 'ShowHiddenHandles', show);
end;


% X-axis labels and grid

if ~isempty(xtick),

 % Tricky thing - if we are drawing a map with the poles, its nasty when the lines get too close
 % together. So we can sort of fudge this by altering MAP_VAR_LIST.lats to be slightly smaller,
 % and then changing it back again later.
 fudge_north='n';fudge_south='n';
 if ~isempty(ytick) & length(ytick)>1,
  if MAP_VAR_LIST.lats(2)==90, 
    fudge_north='y';
    MAP_VAR_LIST.lats(2)=ytick(end);
  end;
  if MAP_VAR_LIST.lats(1)==-90, 
    fudge_south='y';
    MAP_VAR_LIST.lats(1)=ytick(1);
  end;
 end;

 [X,Y,lg,lgI]=feval(MAP_PROJECTION.routine,'xgrid',xtick,gxaxisloc);
 [labs,scl]=m_labels('lon',lg,xlabels);
 
 % Draw the grid. Every time we draw something, I first reshape the matrices into a long
 % row so that a) it plots faster, and b) all lines are given the same handle (which cuts
 % down on the number of children hanging onto the axes).

 [n,m]=size(X);
 line(reshape([X;NaN+ones(1,m)],(n+1)*m,1),reshape([Y;NaN+ones(1,m)],(n+1)*m,1),...
      'linest',glinestyle,'color',gcolor,'linewidth',0.1,'tag','m_grid_xgrid');

 % Get the tick data
 [ltx,lty,utx,uty]=maketicks(X,Y,gticklen,gtickdir);

 % Draw ticks if labels are on top or bottom (not if they are in the middle)

 if strcmp(gxticklabeldir,'middle'),
  if lgI==size(X,1) & strcmp(gxaxisloc,'top'),  % Check to see if the projection supports this option.
   vert='bottom';horiz='center';drawticks=1;
   xx=utx(1,:);yy=uty(1,:);rotang=atan2(diff(uty),diff(utx))*180/pi+90;
  elseif lgI==1 & strcmp(gxaxisloc,'bottom')
   vert='top';horiz='center';drawticks=1;
   xx=ltx(1,:);yy=lty(1,:);rotang=atan2(diff(lty),diff(ltx))*180/pi-90;
  else
   vert='middle';horiz='center';lgIp1=lgI+1;drawticks=0;
   xx=X(lgI,:); yy=Y(lgI,:);rotang=atan2(Y(lgIp1,:)-Y(lgI,:),X(lgIp1,:)-X(lgI,:))*180/pi-90;
  end;
 else
  if lgI==size(X,1) & strcmp(gxaxisloc,'top'),  % Check to see if the projection supports this option.
   vert='middle';horiz='left';drawticks=1;
   xx=utx(1,:);yy=uty(1,:);rotang=atan2(diff(uty),diff(utx))*180/pi+180;
  elseif lgI==1 & strcmp(gxaxisloc,'bottom')
   vert='middle';;horiz='right';drawticks=1;
   xx=ltx(1,:);yy=lty(1,:);rotang=atan2(diff(lty),diff(ltx))*180/pi;
  else
   vert='top';;horiz='center';lgIp1=lgI+1;drawticks=0;
   xx=X(lgI,:); yy=Y(lgI,:);rotang=atan2(Y(lgIp1,:)-Y(lgI,:),X(lgIp1,:)-X(lgI,:))*180/pi;
  end;
 end;

 if strcmp(gbox,'fancy'),
    if gtickdir(1)=='i',
      fancybox(lg,MAP_VAR_LIST.longs,'xgrid','bottom',dpatch,gticklen); 
      drawticks=0;
    else    
      fancybox2(lg,MAP_VAR_LIST.longs,'xgrid','bottom',dpatch,gticklen); 
    end;
 end;    
 if drawticks,
   [n,m]=size(ltx);
   line(reshape([ltx;NaN+ones(1,m)],(n+1)*m,1),reshape([lty;NaN+ones(1,m)],(n+1)*m,1),...
        'linest','-','color',gcolor,'linewidth',glinewidth,'tag','m_grid_xticks-lower','clip','off');
   line(reshape([utx;NaN+ones(1,m)],(n+1)*m,1),reshape([uty;NaN+ones(1,m)],(n+1)*m,1),...
        'linest','-','color',gcolor,'linewidth',glinewidth,'tag','m_grid_xticks-upper','clip','off');
 end;

 % Add the labels! (whew)

 ik=1:size(X,2);

 for k=ik,
   [rotang(k), horizk, vertk] = upright(rotang(k), horiz, vert);
   text(xx(k),yy(k),labs{k},'horizontal',horizk,'vertical',vertk, ...
        'rot',rotang(k),'fontsize',gfontsize*scl(k),'color',gcolor,...
        'tag','m_grid_xticklabel','fontname',gfontname);
 end;

 if fudge_north=='y',
   MAP_VAR_LIST.lats(2)=90;
 end;
 if fudge_south=='y',
   MAP_VAR_LIST.lats(1)=-90;
 end;

end;

if ~isempty(ytick),
 % Y-axis labels and grid

 [X,Y,lt,ltI]=feval(MAP_PROJECTION.routine,'ygrid',ytick,gyaxisloc);
 [labs,scl]=m_labels('lat',lt,ylabels);

 % Draw the grid
 [n,m]=size(X);
 line(reshape([X;NaN+ones(1,m)],(n+1)*m,1),reshape([Y;NaN+ones(1,m)],(n+1)*m,1),...
      'linest',glinestyle,'color',gcolor,'linewidth',0.1,'tag','m_grid_ygrid');

 % Get the tick data
 [ltx,lty,utx,uty]=maketicks(X,Y,gticklen,gtickdir);

 % Draw ticks if labels are on left or right (not if they are in the middle)
 if strcmp(gyticklabeldir,'end'),