: Actually when importing chines, the FreeShip generated curves that
: approximate them are actually chines (crease edges, I mean). So the S&G
: nature is preserved that way, however there are some curves that are
: fitted poorly especially near the razor sharp chine and stern. The model
: check tells me I have leak points. When importing chines the docmentation
: does not explain if the chines have to go all the way from aft to front or
: over smaller sections. For modeling the cockpit for instance, importing
: lines that follow the chines all the way from aft to front around the
: cockpit inevitably leads to unwanted interpolations.

: So it is not really all that bad but I still end up spending lots of time
: guessing about the smarts of FreeShip and still ending up with poor
: interpolations and model errors.

: The original model really does not have that much data: here it is, all
: coordinates in mm starting with a 15' x 28.75" basic model,
: interpolated, stretched and rockered with a few simple commands to the
: final model
: (http://members.cox.net/aling13/kayak/build/fall_2007/combinedView.JPG):
: data = [
: // y, x1, z1, x2, z2, x3, z3, x4, z4, x5, z5;

: 0, -100, 310, -101, 0, -101, 0, -105, 0, -100, 310;

: 250, 0, 155, -1, 0, 48, 280, -5, 0, 0, 300;

: 500, -100, 0, -101, 45, 95, 250, -5, 0, 0, 290;

: 750, 0, 0, 70, 80, 145, 215, -5, 0, 0, 280;
: 1000, 0, 0, 120, 90, 195, 190, -105, 0, 0, 270;
: 1250, 0, 0, 180, 80, 250, 165, 100, 250, 0, 270;
: 1500, 0, 0, 220, 70, 295, 155, 190, 240, 0, 270;
: 1750, 0, 0, 255, 60, 325, 150, 250, 230, 0, 260;
: 1875, 0, 0, 270, 50, 340, 145, 270, 230, -100, 250;
: 2000, 0, 0, 280, 50, 350, 145, 280, 230, -4, 0;
: 2250, 0, 0, 290, 50, 360, 145, 300, 230, -4, 0;
: 2500, 0, 0, 270, 50, 350, 150, 280, 240, -100, 330;
: 2750, 0, 0, 245, 70, 330, 155, 260, 250, 0, 330;
: 3000, 0, 0, 210, 90, 295, 165, 230, 260, 0, 330;
: 3250, 0, 0, 160, 90, 235, 185, 150, 270, 0, 320;
: 3500, 0, 0, 115, 80, 185, 210, 80, 290, 0, 310;
: 3750, 0, 0, 65, 60, 140, 240, -105, 0, 0, 310;
: 4000, -100, 5, -101, 40, 90, 280, -5, 0, 0, 320;
: 4595, -100, 370, -101, 0, -101, 0, -105, 0, -100, 370
: ];

: The negative X coordinates indicate references to other lines (duplicates
: where lines join, another added -100 indicates a line dertivative
: discontinuity. Only 155 data points and some negative numbers that define
: the topology.

: The problems with importing chines in FreeShip are with the topology (the
: negative X numbers in the above matrix). How do I tell FreeShip to
: interpolate exactly from here to there.

: Well I could go with the FreeShip approximation that I have since I don't
: expect exact answers from the hydrodynamics anyway, I just don't know how
: bad the model errors (leaks) are for the results. Could the model sink
: with too many leaks ;-) ? I went overboard already, I think.

don't quite know with your topology, but the manual does state that it draws b-splines betw the pts you give. if it's a chine model, you can check w/ the 2 inputs of model vs markers.

leak points are a snap - use check model, and just fix the ones (usually there is a y value of .00xyx that you just change to 0 - and just change the ones that are at a lower z (height) value than the draft you are doing the hydrostatics on. this'll take less than 5 minutes if you're slow!!