Hello,

Can anyone help?
I was just figuring out how splines worked in megapov when 3.5 beta1 was 
released.  I've included some code below using megapov splines.  What I 
was trying to do was form the shape of a bench using a spline and then 
place a piece of bench at each point that the spline was evaluated.

In megapov, all I needed were the positions within the spline and 
megapov would go ahead and evaluate it placing each piece of bench 
evenly along the spline.  But for pov 3.5 I seem to need to know the 
'fraction' along the spline for each point's spline parameter in order 
to get this even distribution.

I could estimate the parameter value for each position in the spline, 
but that seems a little messy given the power that pov can achieve.  Is 
there a way around this, or something glaringly wrong in my 
understanding of the new syntax :-)

Sorry if this is totally the wrong group for this question.
Steve

/*---megapov 0.7 code */
#init_3d_spline {"BenchSpline", <0,0,0>,<10,5,0>,<20,0,0>,
                                <25,-15,0>,<35,-50,0>,<40,-60,0>,
                                <51,-60.5,0>,<86,-55,0>,<95,-60,0>,
                                <102,-75,0>,<100,-80,0>
        }

#declare UnitBench =
  union {
     box {<-0.5,0.25,-0.1>,<0.5,-0.25,0.1>}
     cylinder {<-0.5,0.25,0>,<0.5,0.25,0>,0.1}
     cylinder {<-0.5,-0.25,0>,<0.5,-0.25,0>,0.1}
    }

#declare Bench =
  union {
     #local cnt = 0;
     #while (cnt < 1)
        #local OldPos = eval_3d_spline ("BenchSpline", cnt - 
1/1000000);
        #local NowPos = eval_3d_spline ("BenchSpline", cnt);
        #local Norm = 90 + degrees(atan2 (NowPos.y - OldPos.y , 
NowPos.x - OldPos.x));
        object {UnitBench scale <1,5,5> rotate <0,90,Norm> translate 
NowPos }
        #local cnt = cnt + 1/35;
     #end
     pigment {red 1}
    }

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