SET MODE "color"
SET WINDOW 0, 1026,0,750
SET COLOR MIX(1) 0,0,0
PRINT" parametric twisted TRIAXIAL 3D"
PRINT" by R. L. Bagula 10 AUG 1999©"
LET s1=500/4
LET s2=s1*750/1026
FOR t=  pi to -PI step -Pi/100
    LET c=c+1
    FOR p= -PI to Pi step Pi/200
        REM Angular probability
        LET pp=sqr(t^2+p^2)/sqr(2*(pi)^2)
        REM twist between cosine and sine triaxial 3d's
        LET x1=(1-pp)*cos(t)*cos(p)+pp*sin(t)*sin(p)
        LET y1=(1-pp)*cos(t+2*pi/3)*cos(p+2*pi/3)+pp*sin(t+2*pi/3)*sin(p+2*pi/3)
        LET z1=(1-pp)*cos(t+4*pi/3)*cos(p+4*pi/3)+pp*sin(t+4*pi/3)*sin(p+4*pi/3)
        LET xx=2*z1/(1+x1/4)
        LET yy=2*y1/(1+x1/4)
        LET xxx=2*x1/(1+z1/4)
        LET yyy=2*y1/(1+z1/4)
        LET x2=cos(pi/4)*x1-sin(pi/4)*y1
        LET y2=sin(pi/4)*x1+cos(pi/4)*y1
        LET x45=2*z1/(1+x2/4)
        LET y45=2*y2/(1+x2/4)

        SET COLOR 255-c
        PLOT 1026/2+s1*xx-200,750/2+s1*(750/1026)*yy-150
        SET COLOR 128-c
        PLOT 1026/2+s1*xxx+200,750/2+s1*(750/1026)*yyy+150
        SET COLOR abs(64-c)
        PLOT 1026/2+s1*x45-200,750/2+s1*(750/1026)*y45+150
    NEXT p
    PLOT
NEXT t
END