视频

拓展学习

例1  利用曲线对象绘制五环图案。

t=-0.1 : 0.1 : 2*pi;

x=cos(t);  y=sin(t);

line(x,y,'Color','b')

line(x+1.2,y-1,'Color','y')

line(x+2.4,y,'Color','k')

line(x+3.6,y-1,'Color','g')

line(x+4.8,y,'Color','r')

ha=gca;

for n=1:size(ha.Children)

    ha.Children(n).LineWidth=5;

end

ha.XLim=[-2,7];

ha.YLim=[-3,2];

axis equal

例2  利用曲面对象绘制立体圆环

r=linspace(0,2*pi,60);

[u,v]=meshgrid(r);

x=(8+3*cos(v)).*cos(u);

y=(8+3*cos(v)).*sin(u);

z=3*sin(v);

axes('view',[-37.5,30])

hs=surface(x,y,z);

axis equal;

hs.EdgeColor='none';

hs.FaceColor='interp';

例3  绘制光照处理后的圆环面并观察不同光照模式下的效果。

r=linspace(0,2*pi,60); [u,v]=meshgrid(r);

x=(8+3*cos(v)).*cos(u); y=(8+3*cos(v)).*sin(u); z=3*sin(v);

axes('Position',[0.05,0.675,1.0,0.3],  'View',[-37.5,30]);

hs1=surface(x,y,z); axis equal;

hs1.EdgeColor='none';  hs1.FaceColor='interp';

axes('Position',[0.05,0.35,1.0,0.3],  'View',[-37.5,30]);

hs2=surface(x,y,z); axis equal;

hs2.EdgeColor='none';  hs2.FaceColor='interp';

light('Position',[0,0,8])

lighting  flat

axes('Position',[0.05,0.025,1.0,0.3],  'View',[-37.5,30]);

hs3=surface(x,y,z); axis equal;

hs3.EdgeColor='none';  hs3.FaceColor='interp';

light('Position',[0,0,8])

lighting  phong

例4  绘制具有不同反射特性的圆环面并观察反射特性对图形效果的影响。

r=linspace(0,2*pi,60);  [u,v]=meshgrid(r);

x=(8+3*cos(v)).*cos(u); y=(8+3*cos(v)).*sin(u); z=3*sin(v);

axes('Position',[0.05,0.675,1.0,0.3],'View',[-37.5,30]);

hs1=surface(x,y,z);axis equal;

hs1.EdgeColor='none';hs1.FaceColor='interp';

light('Position',[0,0,8]) ;lighting  phong

hs1.SpecularStrength=0.1;

axes('Position', [0.05,0.35,1.0,0.3],'View',[-37.5,30]);

hs2=surface(x,y,z);axis equal;

hs2.EdgeColor='none';hs2.FaceColor='interp';

light('Position',[0,0,8]) ;lighting  phong

hs2.SpecularStrength=0.5;

axes('Position', [0.05,0.025,1.0,0.3],'View',[-37.5,30]);

hs3=surface(x,y,z);axis equal;

hs3.EdgeColor='none';hs3.FaceColor='interp';

light('Position',[0,0,8]) ;lighting  phong ;

hs3.SpecularStrength=1.0;