diff --git a/arbitrile.cpp b/arbitrile.cpp
index 83fa63d7..29b1e3b3 100644
--- a/arbitrile.cpp
+++ b/arbitrile.cpp
@@ -14,6 +14,8 @@ EX namespace arb {
 
 EX int affine_limit = 200;
 
+EX bool legacy; /* angleofs command */
+
 #if HDR
 
 struct shape {
@@ -151,6 +153,7 @@ void shape::build_from_angles_edges() {
   int n = isize(angles);
   hyperpoint ctr = Hypc;
   vector<transmatrix> matrices;
+  if(!legacy) for(auto& a: angles) a += M_PI;
   for(int i=0; i<n; i++) {
     matrices.push_back(at);
     println(hlog, "at = ", at);
@@ -172,6 +175,7 @@ void shape::build_from_angles_edges() {
       }
     println(hlog, "ctr = ", ctr);
     }
+  if(!legacy) for(auto& a: angles) a -= M_PI;
   ctr = normalize(ctr);
   for(auto& v: vertices) v = gpushxto0(ctr) * v;
   }
@@ -296,8 +300,14 @@ EX void load(const string& fname, bool after_sliding IS(false)) {
       set_flag(ginf[gArbitrary].flags, qAFFINE, false);
       geom3::apply_always3();
       }
+    else if(ep.eat("legacysign.")) {
+      if(legacy) angleunit *= -1;
+      }
     else if(ep.eat("angleunit(")) angleunit = real(ep.parsepar());
-    else if(ep.eat("angleofs(")) angleofs = real(ep.parsepar());
+    else if(ep.eat("angleofs(")) {
+      angleofs = real(ep.parsepar());
+      if(!legacy) angleofs = 0;
+      }
     else if(ep.eat("distunit(")) distunit = real(ep.parsepar());
     else if(ep.eat("line(")) {
       addflag(arcm::sfLINE);
@@ -893,6 +903,9 @@ int readArgs() {
     shift(); 
     run(args());
     }
+  else if(argis("-arb-legacy")) {
+    legacy = true;
+    }
   else if(argis("-arb-slider")) {
     PHASEFROM(2);
     shift();
diff --git a/util.cpp b/util.cpp
index d4aa7c4b..7d1c8c33 100644
--- a/util.cpp
+++ b/util.cpp
@@ -297,10 +297,14 @@ cld exp_parser::parse(int prio) {
     if(result < 0) result = -result;
     while(result > 2 * M_PI) result -= 2 * M_PI;
     if(result > M_PI) result = 2 * M_PI - result;
-    res = M_PI - result;
-
-    if(extra_params.count("angleofs"))
-      res -= extra_params["angleofs"];
+    
+    if(arb::legacy) {
+      res = M_PI - result;
+      if(extra_params.count("angleofs"))
+        res -= extra_params["angleofs"];
+      }
+    else
+      res = result;
 
     if(extra_params.count("angleunit"))
       res /= extra_params["angleunit"];