light tools模拟时都是中心暗，周围有亮圆环。
模拟光源为朗伯点光源。
8rZJvE#c
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/?(\6Z_A 0<ze'FbV] 是根据这篇
论文编的matlab代码。
K;uO<{a)r R*S9[fqC[ 
4\?z ^^
!UPK y$ 哪位大神指点一下
VPC7Dh%. clear;
:`jB1rI H=20;
)-jA4!& a=100;
_mBFmXHHS$ itheta=0;
19#s:nt9 i=1;
'.{tE* for theta=0:0.0001:pi/2
*P:!lO\| if abs(integral(@(y)cos(y),itheta(i),theta)-1/a)<=0.00005
As}3VBd itheta(i+1)=theta;
/- Fv C^Fj i=i+1;
=qWcw7!" end
0R21"]L_M end
}Mv$Up R=30;
| XGj97#M r=0;
@XJzM]*w& for i=1:a
=\ek;d0Tqb r(i+1)=sqrt(R^2/a+r(i)^2);
'?gF9: end
l.>3gjr I(:,1)=sin(itheta);
v.Vd js I(:,2)=cos(itheta);
ffH]`N N=[0,1];
[}+h86: y P=[0,5];
%tK^&rw% O=[0,1];
FN+x<VXo( n=1.5896;
uge~*S for i=1:a;
)/:j$aq P(i+1,1)=( N(i,1)*P(i,1) + N(i,2)*P(i,2) ) / ( N(i,1) + N(i,2)*I(i+1,2)/I(i+1,1) );
4{v ?<x8 P(i+1,2)= P(i+1,1) * I(i+1,2) / I(i+1,1);
1#w'<}h#U O(i+1,1)=( r(i) - P(i+1,1) ) / sqrt( (r(i)-P(i+1,1))^2 + (H-P(i+1,2))^2);
ow<z @^ 3' O(i+1,2)=(H-P(i+1,2)) / sqrt( (r(i)-P(i+1,1))^2 + (H-P(i+1,2))^2 );
Jc=~BT_G N(i+1,=( O(i+1, - n*I(i+1,) / sqrt( 1 + n^2 - 2*n*dot(O(i+1,,I(i+1,) );
O)FkpZc@9c end
>2^|r8l5 P(:,3)=0;
8MZ:= plot(P(:,1),P(:,2));
( ah^</ &_1x-@oI2: 
