Example #1
0
int
main(int argc, const char *argv[]) {
  const char *me;
  char *err, *outS;
  double eval[3], matA[9], matB[9], sval[3], uu[9], vv[9], escl[5],
    view[3];
  float matAf[9], matBf[16];
  float pp[3], qq[4], mR[9], len, gamma;
  float os, vs, rad, AB[2], ten[7];
  hestOpt *hopt=NULL;
  airArray *mop;
  limnObject *obj;
  limnLook *look; int lookRod, lookSoid;
  float kadsRod[3], kadsSoid[3];
  int gtype, partIdx=-1; /* sssh */
  int res;
  FILE *file;

  me = argv[0];
  hestOptAdd(&hopt, "sc", "evals", airTypeDouble, 3, 3, eval, "1 1 1",
             "original eigenvalues of tensor to be visualized");
  hestOptAdd(&hopt, "AB", "A, B exponents", airTypeFloat, 2, 2, AB, "nan nan",
             "Directly set the A, B parameters to the superquadric surface, "
             "over-riding the default behavior of determining them from the "
             "scalings \"-sc\" as superquadric tensor glyphs");
  hestOptAdd(&hopt, "os", "over-all scaling", airTypeFloat, 1, 1, &os, "1",
             "over-all scaling (multiplied by scalings)");
  hestOptAdd(&hopt, "vs", "view-dir scaling", airTypeFloat, 1, 1, &vs, "1",
             "scaling along view-direction (to show off bas-relief "
             "ambibuity of ellipsoids versus superquads)");
  hestOptAdd(&hopt, "es", "extra scaling", airTypeDouble, 5, 5, escl,
             "2 1 0 0 1", "extra scaling specified with five values "
             "0:tensor|1:geometry|2:none vx vy vz scaling");
  hestOptAdd(&hopt, "fr", "from (eye) point", airTypeDouble, 3, 3, &view,
             "4 4 4", "eye point, needed for non-unity \"-vs\"");
  hestOptAdd(&hopt, "gamma", "superquad sharpness", airTypeFloat, 1, 1,
             &gamma, "0",
             "how much to sharpen edges as a "
             "function of differences between eigenvalues");
  hestOptAdd(&hopt, "g", "glyph shape", airTypeEnum, 1, 1, &gtype, "sqd",
             "glyph to use; not all are implemented here",
             NULL, tenGlyphType);
  hestOptAdd(&hopt, "pp", "x y z", airTypeFloat, 3, 3, pp, "0 0 0",
             "transform: rotation identified by"
             "location in quaternion quotient space");
  hestOptAdd(&hopt, "r", "radius", airTypeFloat, 1, 1, &rad, "0.015",
             "black axis cylinder radius (or 0.0 to not drawn these)");
  hestOptAdd(&hopt, "res", "resolution", airTypeInt, 1, 1, &res, "25",
             "tesselation resolution for both glyph and axis cylinders");
  hestOptAdd(&hopt, "pg", "ka kd ks", airTypeFloat, 3, 3, kadsSoid,
             "0.2 0.8 0.0",
             "phong coefficients for glyph");
  hestOptAdd(&hopt, "pr", "ka kd ks", airTypeFloat, 3, 3, kadsRod, "1 0 0",
             "phong coefficients for black rods (if being drawn)");
  hestOptAdd(&hopt, "o", "output OFF", airTypeString, 1, 1, &outS, "out.off",
             "output file to save OFF into");
  hestParseOrDie(hopt, argc-1, argv+1, NULL,
                 me, info, AIR_TRUE, AIR_TRUE, AIR_TRUE);
  mop = airMopNew();
  airMopAdd(mop, hopt, (airMopper)hestOptFree, airMopAlways);
  airMopAdd(mop, hopt, (airMopper)hestParseFree, airMopAlways);

  obj = limnObjectNew(1000, AIR_TRUE);
  airMopAdd(mop, obj, (airMopper)limnObjectNix, airMopAlways);

  if (!( 0 == escl[0] || 1 == escl[0] || 2 == escl[0] )) {
    fprintf(stderr, "%s: escl[0] %g not 0, 1 or 2\n", me, escl[0]);
    airMopError(mop); return 1;
  }
  if (!(tenGlyphTypeBox == gtype ||
        tenGlyphTypeSphere == gtype ||
        tenGlyphTypeSuperquad == gtype)) {
    fprintf(stderr, "%s: got %s %s, but here only do %s, %s, or %s\n", me,
            tenGlyphType->name,
            airEnumStr(tenGlyphType, gtype),
            airEnumStr(tenGlyphType, tenGlyphTypeBox),
            airEnumStr(tenGlyphType, tenGlyphTypeSphere),
            airEnumStr(tenGlyphType, tenGlyphTypeSuperquad));
    airMopError(mop); return 1;
  }

  /* create limnLooks for glyph and for rods */
  lookSoid = limnObjectLookAdd(obj);
  look = obj->look + lookSoid;
  ELL_4V_SET(look->rgba, 1, 1, 1, 1);
  ELL_3V_COPY(look->kads, kadsSoid);

  look->spow = 0;
  lookRod = limnObjectLookAdd(obj);
  look = obj->look + lookRod;
  ELL_4V_SET(look->rgba, 0, 0, 0, 1);
  ELL_3V_COPY(look->kads, kadsRod);
  look->spow = 0;

  ELL_3M_IDENTITY_SET(matA); /* A = I */
  ELL_3V_SCALE(eval, os, eval);
  ELL_3M_SCALE_SET(matB, eval[0], eval[1], eval[2]); /* B = diag(eval) */
  ell_3m_post_mul_d(matA, matB); /* A = B*A = diag(eval) */

  if (0 == escl[0]) {
    scalingMatrix(matB, escl + 1, escl[4]);
    ell_3m_post_mul_d(matA, matB);
  }

  if (1 != vs) {
    if (!ELL_3V_LEN(view)) {
      fprintf(stderr, "%s: need non-zero view for vs %g != 1\n", me, vs);
      airMopError(mop); return 1;
    }
    scalingMatrix(matB, view, vs);
    /* the scaling along the view direction is a symmetric matrix,
       but applying that scaling to the symmetric input tensor
       is not necessarily symmetric */
    ell_3m_post_mul_d(matA, matB);  /* A = B*A */
  }
  /* so we do an SVD to get rotation U and the scalings sval[] */
  /* U * diag(sval) * V */
  ell_3m_svd_d(uu, sval, vv, matA, AIR_TRUE);

  /*
  fprintf(stderr, "%s: ____________________________________\n", me);
  fprintf(stderr, "%s: mat = \n", me);
  ell_3m_print_d(stderr, matA);
  fprintf(stderr, "%s: uu = \n", me);
  ell_3m_print_d(stderr, uu);
  ELL_3M_TRANSPOSE(matC, uu);
  ELL_3M_MUL(matB, uu, matC);
  fprintf(stderr, "%s: uu * uu^T = \n", me);
  ell_3m_print_d(stderr, matB);
  fprintf(stderr, "%s: sval = %g %g %g\n", me, sval[0], sval[1], sval[2]);
  fprintf(stderr, "%s: vv = \n", me);
  ell_3m_print_d(stderr, vv);
  ELL_3M_MUL(matB, vv, vv);
  fprintf(stderr, "%s: vv * vv^T = \n", me);
  ELL_3M_TRANSPOSE(matC, vv);
  ELL_3M_MUL(matB, vv, matC);
  ell_3m_print_d(stderr, matB);
  ELL_3M_IDENTITY_SET(matA);
  ell_3m_pre_mul_d(matA, uu);
  ELL_3M_SCALE_SET(matB, sval[0], sval[1], sval[2]);
  ell_3m_pre_mul_d(matA, matB);
  ell_3m_pre_mul_d(matA, vv);
  fprintf(stderr, "%s: uu * diag(sval) * vv = \n", me);
  ell_3m_print_d(stderr, matA);
  fprintf(stderr, "%s: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n", me);
  */

  /* now create symmetric matrix out of U and sval */
  /* A = I */
  ELL_3M_IDENTITY_SET(matA);
  ell_3m_pre_mul_d(matA, uu);   /* A = A*U = I*U = U */
  ELL_3M_SCALE_SET(matB, sval[0], sval[1], sval[2]); /* B = diag(sval) */
  ell_3m_pre_mul_d(matA, matB); /* A = U*diag(sval) */
  ELL_3M_TRANSPOSE(matB, uu);
  ell_3m_pre_mul_d(matA, matB); /* A = U*diag(sval)*U^T */
  TEN_M2T(ten, matA);

  partIdx = soidDoit(obj, lookSoid,
                     gtype, gamma, res,
                     (AIR_EXISTS(AB[0]) && AIR_EXISTS(AB[1])) ? AB : NULL,
                     ten);

  if (1 == escl[0]) {
    scalingMatrix(matB, escl + 1, escl[4]);
    ELL_43M_INSET(matBf, matB);
    limnObjectPartTransform(obj, partIdx, matBf);
  }
  /* this is a rotate on the geomtry; nothing to do with the tensor */
  ELL_4V_SET(qq, 1, pp[0], pp[1], pp[2]);
  ELL_4V_NORM(qq, qq, len);
  ell_q_to_3m_f(mR, qq);
  ELL_43M_INSET(matBf, mR);
  limnObjectPartTransform(obj, partIdx, matBf);

  if (rad) {
    partIdx = limnObjectCylinderAdd(obj, lookRod, 0, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, (1-eval[0])/2, rad, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, (1+eval[0])/2, 0.0, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 0, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, (1-eval[0])/2, rad, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, -(1+eval[0])/2, 0.0, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 1, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, (1-eval[1])/2, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, (1+eval[1])/2, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 1, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, (1-eval[1])/2, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, -(1+eval[1])/2, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 2, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, rad, (1-eval[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, 0.0, (1+eval[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 2, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, rad, (1-eval[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, 0.0, -(1+eval[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);
  }

  file = airFopen(outS, stdout, "w");
  airMopAdd(mop, file, (airMopper)airFclose, airMopAlways);

  if (limnObjectWriteOFF(file, obj)) {
    airMopAdd(mop, err = biffGetDone(LIMN), airFree, airMopAlways);
    fprintf(stderr, "%s: trouble:\n%s\n", me, err);
    airMopError(mop); return 1;
  }

  airMopOkay(mop);
  return 0;
}
Example #2
0
void
tend_helixDoit(Nrrd *nout, double bnd,
               double orig[3], double i2w[9], double mf[9],
               double r, double R, double S, double angle, int incrtwist,
               double ev[3], double bgEval) {
  int sx, sy, sz, xi, yi, zi;
  double th, t0, t1, t2, t3, v1, v2,
    wpos[3], vpos[3], mfT[9],
    W2H[9], H2W[9], H2C[9], C2H[9], fv[3], rv[3], uv[3], mA[9], mB[9], inside,
    tmp[3], len;
  float *out;

  sx = nout->axis[1].size;
  sy = nout->axis[2].size;
  sz = nout->axis[3].size;
  out = (float*)nout->data;
  ELL_3M_TRANSPOSE(mfT, mf);
  for (zi=0; zi<sz; zi++) {
    fprintf(stderr, "zi = %d/%d\n", zi, sz);
    for (yi=0; yi<sy; yi++) {
      for (xi=0; xi<sx; xi++) {
        ELL_3V_SET(tmp, xi, yi, zi);
        ELL_3MV_MUL(vpos, i2w, tmp);
        ELL_3V_INCR(vpos, orig);

#define WPOS(pos, th) ELL_3V_SET((pos),R*cos(th), R*sin(th), S*(th)/(2*AIR_PI))
#define VAL(th) (WPOS(wpos, th), ELL_3V_DIST(wpos, vpos))
#define RR 0.61803399
#define CC (1.0-RR)
#define SHIFT3(a,b,c,d) (a)=(b); (b)=(c); (c)=(d)
#define SHIFT2(a,b,c)   (a)=(b); (b)=(c)
        
        th = atan2(vpos[1], vpos[0]);
        th += 2*AIR_PI*floor(0.5 + vpos[2]/S - th/(2*AIR_PI));
        if (S*th/(2*AIR_PI) > vpos[2]) {
          t0 = th - AIR_PI; t3 = th;
        } else {
          t0 = th; t3 = th + AIR_PI;
        }
        t1 = RR*t0 + CC*t3;
        t2 = CC*t0 + RR*t3;
        v1 = VAL(t1);
        v2 = VAL(t2);
        while ( t3-t0 > 0.000001*(AIR_ABS(t1)+AIR_ABS(t2)) ) {
          if (v1 < v2) {
            SHIFT3(t3, t2, t1, CC*t0 + RR*t2);
            SHIFT2(v2, v1, VAL(t1));
          } else {
            SHIFT3(t0, t1, t2, RR*t1 + CC*t3);
            SHIFT2(v1, v2, VAL(t2));
          }
        }
        /* t1 (and t2) are now the th for which the point on the helix
           (R*cos(th), R*sin(th), S*(th)/(2*AIR_PI)) is closest to vpos */

        WPOS(wpos, t1);
        ELL_3V_SUB(wpos, vpos, wpos);
        ELL_3V_SET(fv, -R*sin(t1), R*cos(t1), S/AIR_PI);  /* helix tangent */
        ELL_3V_NORM(fv, fv, len);
        ELL_3V_COPY(rv, wpos);
        ELL_3V_NORM(rv, rv, len);
        len = ELL_3V_DOT(rv, fv);
        ELL_3V_SCALE(tmp, -len, fv);
        ELL_3V_ADD2(rv, rv, tmp);
        ELL_3V_NORM(rv, rv, len);  /* rv now normal to helix, closest to 
                                      pointing to vpos */
        ELL_3V_CROSS(uv, rv, fv);
        ELL_3V_NORM(uv, uv, len);  /* (rv,fv,uv) now right-handed frame */
        ELL_3MV_ROW0_SET(W2H, uv); /* as is (uv,rv,fv) */
        ELL_3MV_ROW1_SET(W2H, rv);
        ELL_3MV_ROW2_SET(W2H, fv);
        ELL_3M_TRANSPOSE(H2W, W2H);
        inside = 0.5 - 0.5*airErf((ELL_3V_LEN(wpos)-r)/(bnd + 0.0001));
        if (incrtwist) {
          th = angle*ELL_3V_LEN(wpos)/r;
        } else {
          th = angle;
        }
        ELL_3M_ROTATE_Y_SET(H2C, th);
        ELL_3M_TRANSPOSE(C2H, H2C);
        ELL_3M_SCALE_SET(mA,
                         AIR_LERP(inside, bgEval, ev[1]),
                         AIR_LERP(inside, bgEval, ev[2]),
                         AIR_LERP(inside, bgEval, ev[0]));
        ELL_3M_MUL(mB, mA, H2C);
        ELL_3M_MUL(mA, mB, W2H);
        ELL_3M_MUL(mB, mA, mf);
        ELL_3M_MUL(mA, C2H, mB);
        ELL_3M_MUL(mB, H2W, mA);
        ELL_3M_MUL(mA, mfT, mB);
        
        TEN_M2T_TT(out, float, mA);
        out[0] = 1.0;
        out += 7;
      }
    }
  }
  return;
}
Example #3
0
int
main(int argc, const char *argv[]) {
  const char *me;
  char *err, *outS;
  double scale[3], matA[9], matB[9], matC[9], sval[3], uu[9], vv[9];
  float matAf[9], matBf[16];
  float p[3], q[4], mR[9], len, gamma;
  float os, vs, rad, AB[2], ten[7], view[3];
  hestOpt *hopt=NULL;
  airArray *mop;
  limnObject *obj;
  limnLook *look; int lookRod, lookSoid;
  int partIdx=-1; /* sssh */
  int res, sphere;
  FILE *file;

  me = argv[0];
  hestOptAdd(&hopt, "sc", "scalings", airTypeDouble, 3, 3, scale, "1 1 1",
             "axis-aligned scaling to do on ellipsoid");
  hestOptAdd(&hopt, "AB", "A, B exponents", airTypeFloat, 2, 2, AB, "nan nan",
             "Directly set the A, B parameters to the superquadric surface, "
             "over-riding the default behavior of determining them from the "
             "scalings \"-sc\" as superquadric tensor glyphs");
  hestOptAdd(&hopt, "os", "over-all scaling", airTypeFloat, 1, 1, &os, "1",
             "over-all scaling (multiplied by scalings)");
  hestOptAdd(&hopt, "vs", "over-all scaling", airTypeFloat, 1, 1, &vs, "1",
             "scaling along view-direction (to show off bas-relief "
             "ambibuity of ellipsoids versus superquads)");
  hestOptAdd(&hopt, "fr", "from (eye) point", airTypeFloat, 3, 3, &view,
             "4 4 4", "eye point, needed for non-unity \"-vs\"");
  hestOptAdd(&hopt, "gamma", "superquad sharpness", airTypeFloat, 1, 1,
             &gamma, "0",
             "how much to sharpen edges as a "
             "function of differences between eigenvalues");
  hestOptAdd(&hopt, "sphere", NULL, airTypeInt, 0, 0, &sphere, NULL,
             "use a sphere instead of a superquadric");
  hestOptAdd(&hopt, "p", "x y z", airTypeFloat, 3, 3, p, "0 0 0",
             "location in quaternion quotient space");
  hestOptAdd(&hopt, "r", "radius", airTypeFloat, 1, 1, &rad, "0.015",
             "black axis cylinder radius (or 0.0 to not drawn these)");
  hestOptAdd(&hopt, "res", "resolution", airTypeInt, 1, 1, &res, "25",
             "tesselation resolution for both glyph and axis cylinders");
  hestOptAdd(&hopt, "o", "output OFF", airTypeString, 1, 1, &outS, "out.off",
             "output file to save OFF into");
  hestParseOrDie(hopt, argc-1, argv+1, NULL,
                 me, info, AIR_TRUE, AIR_TRUE, AIR_TRUE);
  mop = airMopNew();
  airMopAdd(mop, hopt, (airMopper)hestOptFree, airMopAlways);
  airMopAdd(mop, hopt, (airMopper)hestParseFree, airMopAlways);

  obj = limnObjectNew(1000, AIR_TRUE);
  airMopAdd(mop, obj, (airMopper)limnObjectNix, airMopAlways);

  /* create limnLooks for ellipsoid and for rods */
  lookSoid = limnObjectLookAdd(obj);
  look = obj->look + lookSoid;
  ELL_4V_SET(look->rgba, 1, 1, 1, 1);
  ELL_3V_SET(look->kads, 0.2, 0.8, 0);
  look->spow = 0;
  lookRod = limnObjectLookAdd(obj);
  look = obj->look + lookRod;
  ELL_4V_SET(look->rgba, 0, 0, 0, 1);
  ELL_3V_SET(look->kads, 1, 0, 0);
  look->spow = 0;

  ELL_3M_IDENTITY_SET(matA);
  ELL_3V_SCALE(scale, os, scale);
  ELL_3M_SCALE_SET(matB, scale[0], scale[1], scale[2]);
  ell_3m_post_mul_d(matA, matB);
  if (1 != vs) {
    ELL_3V_NORM(view, view, len);
    if (!len) {
      /* HEY: perhaps do more diplomatic error message here */
      fprintf(stderr, "%s: stupido!\n", me);
      exit(1);
    }
    ELL_3MV_OUTER(matB, view, view);
    ELL_3M_SCALE(matB, vs-1, matB);
    ELL_3M_IDENTITY_SET(matC);
    ELL_3M_ADD2(matB, matC, matB);
    ell_3m_post_mul_d(matA, matB);
  }
  ell_3m_svd_d(uu, sval, vv, matA, AIR_TRUE);

  /*
  fprintf(stderr, "%s: ____________________________________\n", me);
  fprintf(stderr, "%s: mat = \n", me);
  ell_3m_print_d(stderr, matA);
  fprintf(stderr, "%s: uu = \n", me);
  ell_3m_print_d(stderr, uu);
  ELL_3M_TRANSPOSE(matC, uu);
  ELL_3M_MUL(matB, uu, matC);
  fprintf(stderr, "%s: uu * uu^T = \n", me);
  ell_3m_print_d(stderr, matB);
  fprintf(stderr, "%s: sval = %g %g %g\n", me, sval[0], sval[1], sval[2]);
  fprintf(stderr, "%s: vv = \n", me);
  ell_3m_print_d(stderr, vv);
  ELL_3M_MUL(matB, vv, vv);
  fprintf(stderr, "%s: vv * vv^T = \n", me);
  ELL_3M_TRANSPOSE(matC, vv);
  ELL_3M_MUL(matB, vv, matC);
  ell_3m_print_d(stderr, matB);
  ELL_3M_IDENTITY_SET(matA);
  ell_3m_pre_mul_d(matA, uu);
  ELL_3M_SCALE_SET(matB, sval[0], sval[1], sval[2]);
  ell_3m_pre_mul_d(matA, matB);
  ell_3m_pre_mul_d(matA, vv);
  fprintf(stderr, "%s: uu * diag(sval) * vv = \n", me);
  ell_3m_print_d(stderr, matA);
  fprintf(stderr, "%s: ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n", me);
  */

  ELL_3M_IDENTITY_SET(matA);
  ell_3m_pre_mul_d(matA, uu);
  ELL_3M_SCALE_SET(matB, sval[0], sval[1], sval[2]);
  ell_3m_pre_mul_d(matA, matB);
  ELL_3M_TRANSPOSE(matB, uu);
  ell_3m_pre_mul_d(matA, matB);
  TEN_M2T(ten, matA);

  partIdx = soidDoit(obj, lookSoid,
                     sphere, gamma, res,
                     (AIR_EXISTS(AB[0]) && AIR_EXISTS(AB[1])) ? AB : NULL,
                     ten);

  ELL_4V_SET(q, 1, p[0], p[1], p[2]);
  ELL_4V_NORM(q, q, len);
  ell_q_to_3m_f(mR, q);
  ELL_43M_INSET(matBf, mR);
  limnObjectPartTransform(obj, partIdx, matBf);

  if (rad) {
    partIdx = limnObjectCylinderAdd(obj, lookRod, 0, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, (1-scale[0])/2, rad, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, (1+scale[0])/2, 0.0, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 0, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, (1-scale[0])/2, rad, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, -(1+scale[0])/2, 0.0, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 1, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, (1-scale[1])/2, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, (1+scale[1])/2, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 1, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, (1-scale[1])/2, rad);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, -(1+scale[1])/2, 0.0);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 2, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, rad, (1-scale[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, 0.0, (1+scale[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);

    partIdx = limnObjectCylinderAdd(obj, lookRod, 2, res);
    ELL_4M_IDENTITY_SET(matAf);
    ELL_4M_SCALE_SET(matBf, rad, rad, (1-scale[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    ELL_4M_TRANSLATE_SET(matBf, 0.0, 0.0, -(1+scale[2])/2);
    ell_4m_post_mul_f(matAf, matBf);
    limnObjectPartTransform(obj, partIdx, matAf);
  }

  file = airFopen(outS, stdout, "w");
  airMopAdd(mop, file, (airMopper)airFclose, airMopAlways);

  if (limnObjectWriteOFF(file, obj)) {
    airMopAdd(mop, err = biffGetDone(LIMN), airFree, airMopAlways);
    fprintf(stderr, "%s: trouble:\n%s\n", me, err);
    airMopError(mop); return 1;
  }

  airMopOkay(mop);
  return 0;
}