diff --git a/drawing.cpp b/drawing.cpp
index 37d180b1..036b21bd 100644
--- a/drawing.cpp
+++ b/drawing.cpp
@@ -488,8 +488,10 @@ bool behind3(shiftpoint h) {
     return lp_apply(inverse_exp(h))[2] < 0;
   if(pmodel == mdLiePerspective)
     return lp_apply(lie_log(h))[2] < 0;
+  #if MAXMDIM >= 4
   if(pmodel == mdRelPerspective)
     return lp_apply(rel_log(h, false))[2] < 0;
+  #endif
   return h[2] < 0;
   }
 
diff --git a/hyperpoint.cpp b/hyperpoint.cpp
index 48f22611..4161173c 100644
--- a/hyperpoint.cpp
+++ b/hyperpoint.cpp
@@ -459,7 +459,7 @@ EX transmatrix to_other_side(hyperpoint h1, hyperpoint h2) {
     h1 = normalize(h1);
     h2 = normalize(h2);
     transmatrix T = to_other_side(h1, h2);
-    for(int i=0; i<4; i++) T[i][3] = T[3][i] = i == 3;
+    fix4(T);
     geom3::light_flip(false);
     return T;
     }
@@ -487,7 +487,9 @@ EX transmatrix to_other_side(hyperpoint h1, hyperpoint h2) {
 EX ld material(const hyperpoint& h) {
   if(sphere || in_s2xe()) return intval(h, Hypc);
   else if(hyperbolic || in_h2xe()) return -intval(h, Hypc);
+  #if MAXMDIM >= 4
   else if(sl2) return h[2]*h[2] + h[3]*h[3] - h[0]*h[0] - h[1]*h[1];
+  #endif
   else return h[LDIM];
   }
 
@@ -790,8 +792,12 @@ EX transmatrix parabolic13(ld u, ld v) {
   }
 
 EX hyperpoint kleinize(hyperpoint h) {
+  #if MAXMDIM == 3
+  return point3(h[0]/h[2], h[1]/h[2], 1);
+  #else
   if(GDIM == 2) return point3(h[0]/h[2], h[1]/h[2], 1);
   else return point31(h[0]/h[3], h[1]/h[3], h[2]/h[3]);
+  #endif
   }
 
 EX hyperpoint deparabolic13(hyperpoint h) {
@@ -1316,7 +1322,9 @@ EX shiftmatrix orthogonal_move(const shiftmatrix& t, double level) {
 
 /** fix a 3x3 matrix into a 4x4 matrix */
 EX transmatrix fix4(transmatrix t) {
+  #if MAXMDIM > 3
   for(int i=0; i<4; i++) t[3][i] = t[i][3] = i == 3;
+  #endif
   return t;
   }
 
@@ -1379,6 +1387,7 @@ EX hyperpoint mid_at_actual(hyperpoint h, ld v) {
   return rspintox(h) * xpush0(hdist0(h) * v);
   }
 
+#if MAXMDIM >= 4
 /** in 3D, an orthogonal projection of C0 on the given triangle */
 EX hyperpoint orthogonal_of_C0(hyperpoint h0, hyperpoint h1, hyperpoint h2) {
   h0 /= h0[3];
@@ -1393,6 +1402,7 @@ EX hyperpoint orthogonal_of_C0(hyperpoint h0, hyperpoint h1, hyperpoint h2) {
   hyperpoint h = w * denom + d1 * a1 + d2 * a2;
   return normalize(h);
   }
+#endif
 
 EX hyperpoint hpxd(ld d, ld x, ld y, ld z) {
   hyperpoint H = hpxyz(d*x, d*y, z);
@@ -1800,6 +1810,7 @@ EX ld inner3(hyperpoint h1, hyperpoint h2) {
     h1[0] * h2[0] + h1[1] * h2[1];
   }
 
+#if MAXMDIM >= 4
 /** circumscribe for H3 and S3 (not for E3 yet!) */
 EX hyperpoint circumscribe(hyperpoint a, hyperpoint b, hyperpoint c, hyperpoint d) {
   
@@ -1829,6 +1840,7 @@ EX hyperpoint circumscribe(hyperpoint a, hyperpoint b, hyperpoint c, hyperpoint
 
   return h;
   }
+#endif
 
 /** the point in distance dist from 'material' to 'dir' (usually an (ultra)ideal point) */
 EX hyperpoint towards_inf(hyperpoint material, hyperpoint dir, ld dist IS(1)) {
diff --git a/hypgraph.cpp b/hypgraph.cpp
index 72a0c9d0..ea132ee2 100644
--- a/hypgraph.cpp
+++ b/hypgraph.cpp
@@ -642,7 +642,9 @@ EX void apply_other_model(shiftpoint H_orig, hyperpoint& ret, eModel md) {
         /* x wanes as z grows! */
         }
       hyperpoint S = lie_log_correct(H_orig, H);
+      #if MAXMDIM >= 4
       S[3] = 1;
+      #endif
       S = lp_apply(S);
       if(hyperbolic) {
         models::apply_orientation(ret[1], ret[0]);
@@ -652,12 +654,14 @@ EX void apply_other_model(shiftpoint H_orig, hyperpoint& ret, eModel md) {
       return;
       }
 
+    #if MAXMDIM >= 4
     case mdRelPerspective: {
       auto S = rel_log(H_orig, true); S[3] = 1;
       S = lp_apply(S);
       apply_perspective(S, ret);
       return;
       }
+    #endif
 
     case mdPixel:
       ret = H / current_display->radius;
@@ -912,6 +916,7 @@ EX void apply_other_model(shiftpoint H_orig, hyperpoint& ret, eModel md) {
       break;
       }
 
+    #if MAXMDIM >= 4
     case mdRelOrthogonal: {
 
       ret = rel_log(H_orig, true);
@@ -921,6 +926,7 @@ EX void apply_other_model(shiftpoint H_orig, hyperpoint& ret, eModel md) {
       if(!vrhr::rendering()) ret = lp_apply(ret);
       break;
       }
+    #endif
 
     case mdHemisphere: {
   
@@ -2542,6 +2548,7 @@ EX void draw_model_elements() {
   dynamicval<ld> lw(vid.linewidth, vid.linewidth * vid.multiplier_ring);
   switch(pmodel) {
   
+    #if MAXMDIM >= 4
     case mdRelOrthogonal:
     case mdRelPerspective: {
       constexpr ld cc = 3;
@@ -2565,6 +2572,7 @@ EX void draw_model_elements() {
         }
       return;
       }
+    #endif
 
     case mdRotatedHyperboles: {
       queuestr(current_display->xcenter, current_display->ycenter + current_display->radius * pconf.alpha, 0, vid.fsize, "X", ringcolor, 1, 8);
@@ -3299,6 +3307,7 @@ EX shiftpoint lie_exp(hyperpoint h1) {
 /** Compute the Lie logarithm in SL(2,R), which corresponds to a geodesic in AdS; or a geodesic in de Sitter space.
  **/
 
+#if MAXMDIM >= 4
 EX hyperpoint rel_log(shiftpoint h, bool relativistic_length) {
   if(sl2) {
     optimize_shift(h);
@@ -3341,6 +3350,7 @@ EX hyperpoint rel_log(shiftpoint h, bool relativistic_length) {
     }
   throw hr_exception("rel_log in wrong geometry");
   }
+#endif
 
 /** Is Lie movement available? Depends on map geometry, not ambient geometry. */
 EX bool lie_movement_available() {
@@ -3351,7 +3361,9 @@ EX bool lie_movement_available() {
 
 EX hyperpoint lie_log(const shiftpoint h1) {
   hyperpoint h = unshift(h1);
-  if(nil) {
+  if(0) ;
+  #if MAXMDIM >= 4
+  else if(nil) {
     h[3] = 0;
     h[2] -= h[0] * h[1] / 2;
     }
@@ -3380,6 +3392,10 @@ EX hyperpoint lie_log(const shiftpoint h1) {
       h[1] *= z / (exp(+z) - 1);
       }
     }
+  else if(sl2) {
+    return rel_log(h1, false);
+    }
+  #endif
   else if(euclid) {
     h[LDIM] = 0;
     }
@@ -3389,9 +3405,6 @@ EX hyperpoint lie_log(const shiftpoint h1) {
       for(int i=1; i<LDIM; i++)
         h[i] *= h[0] / (exp(h[0])-1);
     }
-  else if(sl2) {
-    return rel_log(h1, false);
-    }
   else {
     /* not implemented */
     }
diff --git a/rug.cpp b/rug.cpp
index 7e167f2f..3e8c6038 100644
--- a/rug.cpp
+++ b/rug.cpp
@@ -870,7 +870,11 @@ bincode get_bincode(hyperpoint h) {
     case gcHyperbolic:
       return acd_bin(hypot_d(3, h));
     case gcSphere: {
+      #if MAXMDIM >= 4
       return acd_bin(h[0]) + acd_bin(h[1]) * sY + acd_bin(h[2]) * sZ + acd_bin(h[3]) * sT;
+      #else
+      return 0;
+      #endif
       }
     }
   return 0;