之前说了m_map的下载、安装与基本使用（Matlab下地形图绘图包m_map安装与使用），以及晕渲地形图的绘制（m_map绘制晕渲（shaded relief）地形图），现在再说一下高分辨率海岸线、国界线与河流的绘制。
高分辨率地形和海岸线数据的安装已经在Matlab下地形图绘图包m_map安装与使用中说的比较详细了，这里不再赘述。
可以打开m_gshhs函数查看具体设置。
>> help m_gshhs
m_gshhs Add a coastline to a given map using
the Global Self-consistant Hierarchical High-resolution
Shorelines, Rivers, and Borders
m_gshhs(RES, (standard line option,...,...) ) draws the coastline
river network, or borders as simple lines.
m_gshhs(RES,'patch' ( ,standard patch options,...,...) ) draws the
coastline as a number of patches (rivers and borders are not
arranged so patches can be drawn).
m_gshhs(RES,'save',FILENAME) saves the extracted coastline data
for the current projection in a file FILENAME. This allows
speedier replotting using M_USERCOAST(FILENAME).
RES: A one-char string (optionally 2 or 3)
First char: resolution - one of
'c' crude
'l' low
'i' intermediate
'h' high
'f' full
Second char: type - one of
'c' GSHHS coastline (default)
'b' WDB Border
'r' WDB River
Third char - if 2nd char is 'b':
'1' Country borders
'2' State/Province and Country borders
- if 2nd char is 'r': '1','2','3','4'
add successively more tributaries
(also maintained is this optional format:
RES - selections resolution
1 or 'crude'
2 or 'low'
3 or 'intermediate'
4 or 'high'
5 or 'full
but please don't use this).
See also m_proj, m_grid, m_coast, m_gshhs_l, m_gshhs_h, m_gshhs_c
m_usercoast
这里简要说一下用法。
c、b、r分别表示海岸线，国界线与河流
c、l、i、h、f 分别表示粗糙/低/中/高/满分辨率
具体使用时，c/b/r与 c/l/i/h/f 二者组合使用。
m_gshhs('lc','patch','k'); % 低分辨率海岸线，陆地填充：黑色
m_gshhs('ib’,’color','k'); % 中分辨率国界线，黑色
m_gshhs('fr','color','b'); % 满分辨率河流，蓝色
下面在m_map绘制晕渲（shaded relief）地形图的基础上说一下河流与国界线的添加。
在晕渲图上只添加灰色的中等分辨率的海岸线。
figname='gshhs1';
figure
m_proj('mercator','long',[96 114],'lat',[10 24]);
caxis([-4000 4000])
% %caxis要放在colormap之前，colormap要放在m_shadedrelief之前
colormap([m_colmap('blue',200);m_colmap('gland',200)])
hc=colorbar;
set(get(hc,'title'),'string','Elevation(m)')
m_etopo2('shadedrelief','lightangle',45);
m_gshhs('ic','color',[.5 .5 .5])
m_grid('box','fancy','tickdir','in','gridlines','no','fontsize',12)
set(gcf,'position',[100 100 800 600])
print('-dpng','-r400',[figname,'.png'])
再添加中等分辨率的河流，分支参数设置为1
figname='gshhs2';
figure
m_proj('mercator','long',[96 114],'lat',[10 24]);
caxis([-4000 4000])
% %caxis要放在colormap之前，colormap要放在m_shadedrelief之前
colormap([m_colmap('blue',200);m_colmap('gland',200)])
hc=colorbar;
set(get(hc,'title'),'string','Elevation(m)')
m_etopo2('shadedrelief','lightangle',45);
m_gshhs('ic','color',[.5 .5 .5])
m_gshhs('ir1','color','b')
m_grid('box','fancy','tickdir','in','gridlines','no','fontsize',12)
set(gcf,'position',[100 100 800 600])
print('-dpng','-r400',[figname,'.png'])
添加中等分辨率的河流，分支参数设置为2
%%
figname='gshhs3';
figure
m_proj('mercator','long',[96 114],'lat',[10 24]);
caxis([-4000 4000])
% %caxis要放在colormap之前，colormap要放在m_shadedrelief之前
colormap([m_colmap('blue',200);m_colmap('gland',200)])
hc=colorbar;
set(get(hc,'title'),'string','Elevation(m)')
m_etopo2('shadedrelief','lightangle',45);
m_gshhs('ic','color',[.5 .5 .5])
m_gshhs('ir2','color','b')
m_grid('box','fancy','tickdir','in','gridlines','no','fontsize',12)
set(gcf,'position',[100 100 800 600])
print('-dpng','-r400',[figname,'.png'])
添加中等分辨率的河流，分支参数设置为3
figname='gshhs4';
figure
m_proj('mercator','long',[96 114],'lat',[10 24]);
caxis([-4000 4000])
% %caxis要放在colormap之前，colormap要放在m_shadedrelief之前
colormap([m_colmap('blue',200);m_colmap('gland',200)])
hc=colorbar;
set(get(hc,'title'),'string','Elevation(m)')
m_etopo2('shadedrelief','lightangle',45);
m_gshhs('ic','color',[.5 .5 .5])
m_gshhs('ir3','color','b')
m_grid('box','fancy','tickdir','in','gridlines','no','fontsize',12)
set(gcf,'position',[100 100 800 600])
添加中等分辨率的河流，分支参数设置为3，添加中等分辨率国界线
figname='gshhs5';
figure
m_proj('mercator','long',[96 114],'lat',[10 24]);
caxis([-4000 4000])
% %caxis要放在colormap之前，colormap要放在m_shadedrelief之前
colormap([m_colmap('blue',200);m_colmap('gland',200)])
hc=colorbar;
set(get(hc,'title'),'string','Elevation(m)')
m_etopo2('shadedrelief','lightangle',45);
m_gshhs('ic','color',[.5 .5 .5])
m_gshhs('ir3','color','b')
m_gshhs('ib','color','k','linewid',1.5)
m_grid('box','fancy','tickdir','in','gridlines','no','fontsize',12)
set(gcf,'position',[100 100 800 600])
print('-dpng','-r400',[figname,'.png'])
添加中等分辨率的河流，分支参数设置为2，添加中等分辨率国界线
figname='gshhs6';
figure
m_proj('mercator','long',[96 114],'lat',[10 24]);
caxis([-4000 4000])
% %caxis要放在colormap之前，colormap要放在m_shadedrelief之前
colormap([m_colmap('blue',200);m_colmap('gland',200)])
hc=colorbar;
set(get(hc,'title'),'string','Elevation(m)')
m_etopo2('shadedrelief','lightangle',45);
m_gshhs('ic','color',[.5 .5 .5])
m_gshhs('ir2','color','b')
m_gshhs('ib','color','k','linewid',1.5)
m_grid('box','fancy','tickdir','in','gridlines','no','fontsize',12)
set(gcf,'position',[100 100 800 600])
print('-dpng','-r400',[figname,'.png'])
END