%% Textured 3D Earth example
%% Options
space_color = 'k';
npanels = 72;
% Number of globe panels around the equator deg/panel = 360/npanels
alpha = 1;
% globe transparency level, 1 = opaque, through 0 = invisible
% Earth texture image
% Anything imread() will handle), but needs to be a 2:1 unprojected globe
% image.
% This is from NASA's Visible Earth site (http://visibleearth.nasa.gov/)
% The actual image link will likely move over time. This one is the 260KB
% version from this page: http://visibleearth.nasa.gov/view_rec.php?id=2430
% image_file = 'http://veimages.gsfc.nasa.gov/2430/land_ocean_ice_2048.jpg';
image_file = 'globe.jpg';
% Mean spherical earth
erad = 6371008.7714;
% equatorial radius (meters)
prad = 6371008.7714;
% polar radius (meters)
erot = 7.2921158553e-5;
% earth rotation rate (radians/sec)
%% Create figure
figure('Color', space_color);
hold on;
% Turn off the normal axes
set(gca, 'NextPlot','add', 'Visible','off');
axis equal;
axis auto;
axis vis3d;
%% Create wireframe globe
% Create a 3D meshgrid of the sphere points using the ellipsoid function
[x, y, z] = ellipsoid(0, 0, 0, erad, erad, prad, npanels);
globe = surf(x, y, -z, 'FaceColor', 'none', 'EdgeColor', 0.5*[1 1 1]);
%% Texturemap the globe
% Load Earth image for texture map
cdata = imread(image_file);
% Set image as color data (cdata) property, and set face color to indicate
% a texturemap, which Matlab expects to be in cdata. Turn off the mesh edges.
set(globe, 'FaceColor', 'texturemap', 'CData', cdata, 'FaceAlpha', alpha, 'EdgeColor', 'none');
%% view
m=200;
n=30;
view(m,n)
%改变初始图形的视角，第一个参数是地球沿极轴旋转的角度，为0时，美洲正对着我们，角度为正时向东
%第二个参数为地球倾斜的角度，为0时赤道正对着我们，角度为正时，地球向南倾斜
%旋转；
disp('请输入您的操作,按Enter键结束：');
ope=input('','s');
if ope=='move'
disp('地球正在旋转...');
disp('请按Ctrl+C键退出');
while 1
for i=1:1800
j=m+i*0.2;
if(j>360)
j=j-360;
end
view(j,n);
pause(0.01);
end
end
end
