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积分1336回帖0西莫币 贡献 威望 存款 阅读权限30最后登录1970-1-1 
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 发表于 2011-8-12 17:45
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来自: 中国北京 
| 不会弄附件,贴出代码,大家复制到文本文档里,然后用magnet运行一下就是椭圆,可以在代码中根据椭圆的尺寸更改,生成自己想要的椭圆 ' Ellipse Drawing Script
 ' The following code will draw an ellipse using Construction Slice lines
 '
 ' Equation of an ellipse: ((x-h)^2)/a^2 + ((y-k)^2)/b^2 = 1
 ' where
 '   (h,k) is the center of the ellipse
 '   a is the semi-major axis length
 '   b is the semi-minor axis length
 '
 ' Parametric equation is used here
 ' x=h+a*cos(t)*cos(theta)-b*sin(t)*sin(theta)
 ' y=k+b*sin(t)*cos(theta)+a*cos(t)*sin(theta)
 ' where
 '   t is the parameter
 '   theta=angle of rotation about center, with respect to x-axis
 
 
 ' Constants
 h=5        'x-coordinate of center of ellipse
 k=7        'y-coordinate of center of ellipse
 a=15       'Semi-major axis length
 b=8        'Semi-minor axis length
 theta=0    'Angle of Rotation (degrees)
 nblines=50 'Number of lines to be used in discretization
 PI=3.14159265358979323846
 
 'Initialization of parameter
 t=0
 
 'Starting point calculation
 x1=h+a*cos(t*PI/180)*cos(theta*PI/180)-b*sin(t*PI/180)*sin(theta*PI/180)
 y1=k+b*sin(t*PI/180)*cos(theta*PI/180)+a*cos(t*PI/180)*sin(theta*PI/180)
 
 For i = 1 to nblines
 
 t=t+(360/nblines) 't is incremented by 360/nblines for each iteration
 
 'End point calculation
 x2=h+a*cos(t*PI/180)*cos(theta*PI/180)-b*sin(t*PI/180)*sin(theta*PI/180)
 y2=k+b*sin(t*PI/180)*cos(theta*PI/180)+a*cos(t*PI/180)*sin(theta*PI/180)
 
 Call getDocument().getView().newLine(x1,y1, x2, y2)
 
 x1=x2
 y1=y2
 
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