source: cpp/frams/_demos/part_shapes.cpp @ 180

// This file is a part of the Framsticks GDK.
// Copyright (C) 2002-2014  Maciej Komosinski and Szymon Ulatowski.  See LICENSE.txt for details.
// Refer to http://www.framsticks.com/ for further information.

#include <stdio.h>
#include <frams/model/model.h>
#include <frams/model/modelparts.h>

int main()
{
        Model m;
        Part *p1, *p2;
        Joint *j;

        m.open();

        // chain of ellipsoids - subsequent parts are placed relative to the previous part's orientation and location
        p1 = m.addNewPart(Part::SHAPE_ELLIPSOID); //initial part
        p1->scale = Pt3D(1.0, 0.7, 0.4);

        Orient rotation = Orient_1; //must be initialized explicitly because the default Orient constructor does not initialize anything
        rotation.rotate(Pt3D(0.1, 0.2, 0.3));

        for (int N = 10; N > 0; N--, p1 = p2)
        {
                p2 = m.addNewPart(Part::SHAPE_ELLIPSOID);
                p2->scale = p1->scale*0.9; //each part is smaller than its predecessor

                Pt3D advance(p1->scale.x, 0, 0); //advance by previous part's ellipsoid x radius
                p2->p = p1->p + p1->o.transform(advance); //advance vector transformed by p1's orientation (i.e., in p1's local coordinates)
                p2->setOrient(p1->o.transform(rotation)); //rotation transformed by p1's orientation

                m.addNewJoint(p1, p2, Joint::SHAPE_SOLID); //all parts must be connected
        }

        // chain of cyllinders - line segments between points calculated from the parametric formula P(a)=(2-2*cos(a),2*sin(a)) (circle with r=2)
        Pt3D prev, next;
        p1 = m.getPart(0);
        for (float a = 0; a<M_PI; a += M_PI / 10)
        {
                Pt3D next(2 - 2 * cos(a), 0, 2 * sin(a));
                if (a>0)
                {
                        p2 = m.addNewPart(Part::SHAPE_CYLINDER);
                        p2->setPositionAndRotationFromAxis(prev, next);
                        p2->scale = Pt3D(prev.distanceTo(next)*0.5, 0.05, 0.05);// distance*0.5 because scale is "radius", not cylinder length

                        m.addNewJoint(p1, p2, Joint::SHAPE_SOLID); //all parts must be connected
                }
                p1 = p2;
                prev = next;
        }

        m.close();
        puts((const char*)m.getF0Geno().toString());
        // the genotype can be fed directly to the genotype viewer, like this:
        // part_shapes | theater -g -
}