diff --git a/qpms/ewald.c b/qpms/ewald.c
index 603fe44..810c12c 100644
--- a/qpms/ewald.c
+++ b/qpms/ewald.c
@@ -902,7 +902,8 @@ int ewald3_sigma_short(
         break;
       case LAT_2D_IN_3D_XYONLY:
         assert((pgen_retdata.flags &PGEN_AT_XY) == PGEN_AT_XY);
-        assert(Rpq_shifted_theta == M_PI_2);
+        assert(fabs(Rpq_shifted_theta - M_PI_2) < DBL_EPSILON * 1024);
+        // assert(Rpq_shifted_theta == M_PI_2); // FIXME this should work as well
         legendre_array = c->legendre0;
         break;
       default:
diff --git a/tests/ewaldshift2.c b/tests/ewaldshift2.c
index e3d0991..77bd250 100644
--- a/tests/ewaldshift2.c
+++ b/tests/ewaldshift2.c
@@ -1,4 +1,4 @@
-// c99 -ggdb -Wall -I ../ ewaldshift2.c ../qpms/ewald.c ../qpms/ewaldsf.c  ../qpms/lattices2d.c -lgsl -lm -lblas
+// c99 -o ewaldshift2 -ggdb -Wall -I ../ ewaldshift2.c ../qpms/ewald.c ../qpms/ewaldsf.c  ../qpms/lattices2d.c -lgsl -lm -lblas
 
 // implementation of the [LT(4.16)] test
 #include <math.h>
diff --git a/tests/ewaldshift_3g.c b/tests/ewaldshift_3g.c
index e3d0991..83b51e9 100644
--- a/tests/ewaldshift_3g.c
+++ b/tests/ewaldshift_3g.c
@@ -1,4 +1,4 @@
-// c99 -ggdb -Wall -I ../ ewaldshift2.c ../qpms/ewald.c ../qpms/ewaldsf.c  ../qpms/lattices2d.c -lgsl -lm -lblas
+// c99 -o ewaldshift_3g -ggdb -Wall -I ../ ewaldshift_3g.c ../qpms/ewald.c ../qpms/ewaldsf.c  ../qpms/lattices2d.c ../qpms/latticegens.c -lgsl -lm -lblas
 
 // implementation of the [LT(4.16)] test
 #include <math.h>
@@ -188,29 +188,17 @@ void ewaldtest_triang_results_free(ewaldtest_triang_results *r) {
   free(r);
 }
 
-
-void dump_points2d_rordered(const points2d_rordered_t *ps, char *filename) {
-  FILE *f = fopen(filename, "w");
-  for (size_t i = 0; i < ps->nrs; ++i) {
-    fprintf(f, "# r = %.16g\n", ps->rs[i]);
-    for (ptrdiff_t j = ps->r_offsets[i]; j < ps->r_offsets[i+1]; ++j)
-      fprintf(f, "%.16g %.16g\n", ps->base[j].x, ps->base[j].y);
-  }
-  fclose(f);
-}
-
-
 static inline double san(double x) {
   return fabs(x) < 1e-13 ? 0 : x;
 }
 
-ewaldtest_triang_results *ewaldtest_triang(const ewaldtest_triang_params p);
+ewaldtest_triang_results *ewaldtest_triang_3g(const ewaldtest_triang_params p);
 
 int main() {
   gsl_set_error_handler(IgnoreUnderflowsGSLErrorHandler);
   for (size_t i = 0; i < sizeof(paramslist)/sizeof(ewaldtest_triang_params); ++i) {
     ewaldtest_triang_params p = paramslist[i];
-    ewaldtest_triang_results *r = ewaldtest_triang(p);
+    ewaldtest_triang_results *r = ewaldtest_triang_3g(p);
     // TODO print per-test header here
     printf("===============================\n");
     printf("a = %g, K = %g, Kmax = %g, Rmax = %g, lMax = %d, eta = %g, k = %g, beta = (%g,%g), ps = (%g,%g), csphase = %g\n",
@@ -246,36 +234,51 @@ int main() {
 int ewaldtest_counter = 0;
 
 
-ewaldtest_triang_results *ewaldtest_triang(const ewaldtest_triang_params p) {
+ewaldtest_triang_results *ewaldtest_triang_3g(const ewaldtest_triang_params p) {
   const double a = p.a; //const double a = p.h * sqrt(3);
+  cart3_t beta3 = cart22cart3xy(p.beta);
+  cart3_t particle_shift3 = cart22cart3xy(p.particle_shift);
  
-  const double A = sqrt(3) * a * a / 2.; // unit cell size
-  const double K_len = 4*M_PI/a/sqrt(3); // reciprocal vector length
-  
+  cart2_t b1, b2, rb1, rb2;
+  if (p.orientation == TRIANGULAR_VERTICAL) {
+    b1.x = 0;
+    b1.y = a;
+    b2.x = a * M_SQRT3 * .5;
+    b2.y = a * .5;
+  } else {
+    b1.x = a;
+    b1.y = 0;
+    b2.x = a * .5;
+    b2.y = a * M_SQRT3 * .5;
+  }
+  if (QPMS_SUCCESS != l2d_reciprocalBasis2pi(b1, b2, &rb1, &rb2))
+    abort();
+
+  const double A = l2d_unitcell_area(b1, b2); // sqrt(3) * a * a / 2.; // unit cell size
+  const double K_len = cart2norm(rb1); //4*M_PI/a/sqrt(3); // reciprocal vector length
+
   
   ewaldtest_triang_results *results = malloc(sizeof(ewaldtest_triang_results));
   results->p = p;
 
-  triangular_lattice_gen_t *Rlg = triangular_lattice_gen_init(a, p.orientation, true, 0); // N.B. orig is included 
-  triangular_lattice_gen_extend_to_r(Rlg, p.maxR + a);
-  triangular_lattice_gen_t *Klg = triangular_lattice_gen_init(K_len, reverseTriangularLatticeOrientation(p.orientation), true, 0);
-  triangular_lattice_gen_extend_to_r(Klg, p.maxK + K_len);
+  //triangular_lattice_gen_t *Rlg = triangular_lattice_gen_init(a, p.orientation, true, 0); // N.B. orig is included 
+  //triangular_lattice_gen_extend_to_r(Rlg, p.maxR + a);
+  //triangular_lattice_gen_t *Klg = triangular_lattice_gen_init(K_len, reverseTriangularLatticeOrientation(p.orientation), true, 0);
+  //triangular_lattice_gen_extend_to_r(Klg, p.maxK + K_len);
 
-  point2d *Rpoints = Rlg->ps.base; 
-  size_t nR = Rlg->ps.r_offsets[Rlg->ps.nrs];
+  //point2d *Rpoints = Rlg->ps.base; 
+  //size_t nR = Rlg->ps.r_offsets[Rlg->ps.nrs];
   
-  if (fabs(p.particle_shift.x) ==0 && fabs(p.particle_shift.y) == 0) {
+  /*if (fabs(p.particle_shift.x) ==0 && fabs(p.particle_shift.y) == 0) {
     points2d_rordered_t Rpos = points2d_rordered_annulus(&(Rlg->ps), 0, false, INFINITY, false);
     Rpoints = Rpos.base + Rpos.r_offsets[0];
     nR = Rpos.r_offsets[Rpos.nrs] - Rpos.r_offsets[0];
-  }
+  }*/
 
-
-
-
-  point2d  *Kpoints = Klg->ps.base;
-  size_t nK = Klg->ps.r_offsets[Klg->ps.nrs];
+  //point2d  *Kpoints = Klg->ps.base;
+  //size_t nK = Klg->ps.r_offsets[Klg->ps.nrs];
   
+  /*
   point2d particle_shift = p.particle_shift;
   point2d minus_ps = {-particle_shift.x, -particle_shift.y};
   point2d Rpoints_plus_shift[nR];
@@ -283,8 +286,17 @@ ewaldtest_triang_results *ewaldtest_triang(const ewaldtest_triang_params p) {
     Rpoints_plus_shift[i].x = Rpoints[i].x - particle_shift.x;
     Rpoints_plus_shift[i].y = Rpoints[i].y - particle_shift.y;
   }
+  */
 
-  
+ 
+  // skip zeroth point if it coincides with origin
+  bool include_origin = !(fabs(p.particle_shift.x) == 0 
+      && fabs(p.particle_shift.y) == 0);
+
+  PGen Rlgen = PGen_xyWeb_new(b1, b2, BASIS_RTOL, CART2_ZERO, 0, include_origin, p.maxR + a, false);
+  //PGen Rlgen_plus_shift = PGen_xyWeb_new(b1, b2, BASIS_RTOL, cart2_scale(-1 /* CHECKSIGN */, particle_shift2), 0, include_origin, p.maxR + a, false);
+  PGen Klgen = PGen_xyWeb_new(rb1, rb2, BASIS_RTOL, CART2_ZERO, 0, true, p.maxK + K_len, false);
+  //PGen Klgen_plus_beta = PGen_xyWeb_new(rb1, rb2, BASIS_RTOL, beta2, 0, true, p.maxK + K_len, false); 
 
   qpms_y_t nelem_sc = qpms_lMax2nelem_sc(p.lMax);
 
@@ -297,26 +309,37 @@ ewaldtest_triang_results *ewaldtest_triang(const ewaldtest_triang_params p) {
 
   qpms_ewald32_constants_t *c = qpms_ewald32_constants_init(p.lMax, p.csphase);
 
-  points2d_rordered_t *Kpoints_plus_beta = points2d_rordered_shift(&(Klg->ps), p.beta,
-      8*DBL_EPSILON, 8*DBL_EPSILON);
+  //points2d_rordered_t *Kpoints_plus_beta = points2d_rordered_shift(&(Klg->ps), p.beta,
+  //    8*DBL_EPSILON, 8*DBL_EPSILON);
 
-  char filename[BUFSIZ];
-  sprintf(filename, "betalattice_%d.out", ewaldtest_counter);
-  dump_points2d_rordered(Kpoints_plus_beta, filename);
+  //char filename[BUFSIZ];
+  //sprintf(filename, "betalattice_%d.out", ewaldtest_counter);
+  //dump_points2d_rordered(Kpoints_plus_beta, filename);
 
 
+  if (0!=ewald3_sigma_long(results->sigmas_long,
+        results->err_sigmas_long, c, p.eta, p.k, A,
+        LAT_2D_IN_3D_XYONLY, &Klgen, false, beta3, particle_shift3))
+      abort();
+#if 0
   if (0!=ewald32_sigma_long_points_and_shift(results->sigmas_long,
         results->err_sigmas_long, c, p.eta, p.k, A,
         nK, Kpoints,
         p.beta, 
         particle_shift /*minus_ps*/ )) 
     abort();
-  if (0!=ewald32_sigma_short_points_and_shift(
+#endif
+  if (0!=ewald3_sigma_short(
+    results->sigmas_short, results->err_sigmas_short, c,
+    p.eta, p.k, LAT_2D_IN_3D_XYONLY, &Rlgen, false,  beta3, particle_shift3))
+    abort();
+  /*if (0!=ewald32_sigma_short_points_and_shift(
         results->sigmas_short, results->err_sigmas_short, c,
         p.eta, p.k,
         nR, Rpoints, p.beta, particle_shift)) 
-    abort();
-  if (0!=ewald32_sigma0(&(results->sigma0), &(results->err_sigma0), c, p.eta, p.k))
+    abort();*/
+  //if (0!=ewald32_sigma0(&(results->sigma0), &(results->err_sigma0), c, p.eta, p.k))
+  if (0!=ewald3_sigma0(&(results->sigma0), &(results->err_sigma0), c, p.eta, p.k))
     abort();
   for(qpms_y_t y = 0; y < nelem_sc; ++y) {
     results->sigmas_total[y] = results->sigmas_short[y] + results->sigmas_long[y];
@@ -329,6 +352,7 @@ ewaldtest_triang_results *ewaldtest_triang(const ewaldtest_triang_params p) {
   results->regsigmas_416 = calloc(nelem_sc, sizeof(complex double));
   results->regsigmas_416[0] = -2 * c->legendre0[gsl_sf_legendre_array_index(0,0)];
   
+#if 0 // not yet implemented for the new API
   {
     double legendres[gsl_sf_legendre_array_n(p.lMax)];
     points2d_rordered_t sel = 
@@ -359,11 +383,21 @@ ewaldtest_triang_results *ewaldtest_triang(const ewaldtest_triang_params p) {
       }
     }
   }
+#else
+  for(qpms_y_t y = 0; y < nelem_sc; ++y) {
+          qpms_l_t n; qpms_m_t m; 
+          qpms_y2mn_sc_p(y, &m, &n);
+          if ((m+n)%2 != 0)
+            continue;
+          results->regsigmas_416[y] = NAN;
+  }
+#endif
 
-  points2d_rordered_free(Kpoints_plus_beta);
+
+  //points2d_rordered_free(Kpoints_plus_beta);
   qpms_ewald32_constants_free(c);
-  triangular_lattice_gen_free(Klg);
-  triangular_lattice_gen_free(Rlg);
+  //triangular_lattice_gen_free(Klg);
+  //triangular_lattice_gen_free(Rlg);
   ++ewaldtest_counter;
   return results;
 }