diff --git a/basegraph.cpp b/basegraph.cpp
index 4cfd3e9e..6664c88d 100644
--- a/basegraph.cpp
+++ b/basegraph.cpp
@@ -158,7 +158,7 @@ bool cameraangle_on;
 void setcameraangle(bool b) {
   if(cameraangle_on != b) {
     cameraangle_on = b;
-    ld cam = vid.camera_angle * M_PI / 180;
+    ld cam = vid.camera_angle * degree;
 
     GLfloat cc = cos(cam);
     GLfloat ss = sin(cam * (b?1:-1));
diff --git a/config.cpp b/config.cpp
index fed5c1a6..6c5e15e2 100644
--- a/config.cpp
+++ b/config.cpp
@@ -1071,7 +1071,7 @@ string explain3D(ld *param) {
         "the center of your vision and a faraway location is 1/cosh(c) = %4).",
         fts3(camera),
         fts3(depth),
-        fts3(atan(1/cosh(camera))*2*180/M_PI),
+        fts3(atan(1/cosh(camera))*2/degree),
         fts3(1/cosh(camera)));
   if(param == &depth)
     return
diff --git a/conformal.cpp b/conformal.cpp
index 68ba4d63..6c36dfdc 100644
--- a/conformal.cpp
+++ b/conformal.cpp
@@ -374,7 +374,7 @@ namespace conformal {
     hyperpoint next = calc_relative_matrix(v[ph+1]->base, v[ph]->base, C0) * 
       v[ph+1]->at * C0;
   
-    View = spin(M_PI/180 * rotation) * xpush(-(phase-ph) * hdist(now, next)) * View;
+    View = spin(rotation * degree) * xpush(-(phase-ph) * hdist(now, next)) * View;
     playermoved = false;
     centerover.at = v[ph]->base;
     compute_graphical_distance();
@@ -394,10 +394,10 @@ namespace conformal {
     }
 
   void configure() {
-    ld ball = -vid.ballangle * M_PI / 180;
+    ld ball = -vid.ballangle * degree;
     cos_ball = cos(ball), sin_ball = sin(ball);
-    ocos = cos(model_orientation * M_PI / 180);
-    osin = sin(model_orientation * M_PI / 180);
+    ocos = cos(model_orientation * degree);
+    osin = sin(model_orientation * degree);
     model_straight = (ocos > 1 - 1e-9);
     if(conformal::on) conformal::apply();
     }
@@ -741,7 +741,7 @@ namespace conformal {
             // cos(phi) * cos(phi) = 1/K
             if(sphere && vid.stretch >= 1) {
               ld phi = acos(sqrt(1/vid.stretch));
-              dialog::addInfo(XLAT("The current value makes the map conformal at the latitude of %1 (%2°).", fts(phi), fts(phi * 180 / M_PI)));
+              dialog::addInfo(XLAT("The current value makes the map conformal at the latitude of %1 (%2°).", fts(phi), fts(phi / degree)));
               }
             else if(hyperbolic && abs(vid.stretch) <= 1 && abs(vid.stretch) >= 1e-9) {
               ld phi = acosh(abs(sqrt(1/vid.stretch)));
diff --git a/graph.cpp b/graph.cpp
index fb7a9c9a..8be319a0 100644
--- a/graph.cpp
+++ b/graph.cpp
@@ -4891,7 +4891,7 @@ void drawcell(cell *c, transmatrix V, int spinv, bool mirrored) {
         downspin = atan2(VC0[1], VC0[0]);
         downspin -= M_PI/2;
         if(rev) downspin += M_PI;
-        downspin += M_PI/180 * conformal::rotation;
+        downspin += conformal::rotation * degree;
         while(downspin < -M_PI) downspin += 2*M_PI;
         while(downspin > +M_PI) downspin -= 2*M_PI;
         downspin = downspin * min(spd, (double)1);
@@ -5487,7 +5487,7 @@ void calcparam() {
   vid.xcenter += vid.scrsize * vid.xposition;
   vid.ycenter += vid.scrsize * vid.yposition;
 
-  stereo::tanfov = tan(stereo::fov * M_PI / 360);
+  stereo::tanfov = tan(stereo::fov * degree / 2);
   
   if(pmodel) 
     stereo::scrdist = vid.xres / 2 / stereo::tanfov;
diff --git a/hyper.h b/hyper.h
index 076db16e..c7726974 100644
--- a/hyper.h
+++ b/hyper.h
@@ -4326,5 +4326,7 @@ dqi_poly& queuecurve(color_t linecol, color_t fillcol, PPR prio);
 bool haveaura();
 
 string parser_help();
+
+static const ld degree = M_PI / 180;
 }
 
diff --git a/hyperweb.cpp b/hyperweb.cpp
index 772dc63b..c5612931 100644
--- a/hyperweb.cpp
+++ b/hyperweb.cpp
@@ -158,9 +158,9 @@ transmatrix getOrientation() {
   beta = EM_ASM_DOUBLE({ return rotation_beta; });
   gamma = EM_ASM_DOUBLE({ return rotation_gamma; });
   return 
-    rotmatrix(alpha * M_PI / 180, 0, 1) *
-    rotmatrix(beta * M_PI / 180, 1, 2) *
-    rotmatrix(gamma * M_PI / 180, 0, 2);
+    rotmatrix(alpha * degree, 0, 1) *
+    rotmatrix(beta * degree, 1, 2) *
+    rotmatrix(gamma * degree, 0, 2);
   }
 #endif
 
diff --git a/hypgraph.cpp b/hypgraph.cpp
index 4049b895..9093e0d5 100644
--- a/hypgraph.cpp
+++ b/hypgraph.cpp
@@ -13,7 +13,7 @@ void ghcheck(hyperpoint &ret, const hyperpoint &H) {
   }
 
 void camrotate(ld& hx, ld& hy) {
-  ld cam = vid.camera_angle * M_PI / 180;
+  ld cam = vid.camera_angle * degree;
   GLfloat cc = cos(cam);
   GLfloat ss = sin(cam);
   ld ux = hx, uy = hy * cc + ss, uz = cc - ss * hy;
@@ -221,7 +221,7 @@ void make_twopoint(ld& x, ld& y) {
 hyperpoint mobius(hyperpoint h, ld angle, ld scale = 1) {
   using namespace hyperpoint_vec;
   h = perspective_to_space(h * scale, 1, gcSphere);
-  h = rotmatrix(angle * M_PI / 180, 1, 2) * h;
+  h = rotmatrix(angle * degree, 1, 2) * h;
   return space_to_perspective(h, 1) / scale;
   }
 
@@ -253,7 +253,7 @@ void applymodel(hyperpoint H, hyperpoint& ret) {
       else {
         ld tx = H[0];
         ld ty = H[1];
-        ld cam = vid.camera_angle * M_PI / 180;
+        ld cam = vid.camera_angle * degree;
         GLfloat cc = cos(cam);
         GLfloat ss = sin(cam);
         ld ux = tx, uy = ty * cc - ss * tz, uz = tz * cc + ss * ty;
@@ -1134,7 +1134,7 @@ void circle_around_center(ld radius, color_t linecol, color_t fillcol, PPR prio)
     queuecircle(vid.xcenter, vid.ycenter, r * vid.radius, linecol, prio, fillcol);
     return;
     }  
-  for(int i=0; i<360; i++) curvepoint(xspinpush0(i * 2 * M_PI / 360, 10));
+  for(int i=0; i<=360; i++) curvepoint(xspinpush0(i * degree, 10));
   auto& c = queuecurve(linecol, fillcol, prio);
   if(pmodel == mdDisk && hyperbolic && vid.alpha <= -1)
     c.flags |= POLY_FORCE_INVERTED;
@@ -1148,7 +1148,7 @@ void draw_model_elements() {
     circle_around_center(M_PI/2, ringcolor, 0, PPR::CIRCLE);    
 
   if(pmodel == mdTwoPoint) {
-    ld a = -conformal::model_orientation * M_PI / 180;
+    ld a = -conformal::model_orientation * degree;
     queuechr(xspinpush0(a, +vid.twopoint_param), vid.xres / 100, 'X', ringcolor >> 8);
     queuechr(xspinpush0(a, -vid.twopoint_param), vid.xres / 100, 'X', ringcolor >> 8);
     }
diff --git a/mapeditor.cpp b/mapeditor.cpp
index f5c47b70..95e9946c 100644
--- a/mapeditor.cpp
+++ b/mapeditor.cpp
@@ -993,7 +993,7 @@ namespace mapeditor {
         // at H1: (rh2 - a1 - M_PI)
         // at H2: (a2+M_PI - rh1)
         // total: rh2 - rh1
-        // ld z = 180 / M_PI;
+        // ld z = degree;
         ld x = b2 - b1 + M_PI;
         while(x > M_PI) x -= 2 * M_PI;
         while(x < -M_PI) x += 2 * M_PI;
@@ -1145,7 +1145,7 @@ namespace mapeditor {
       displayfr(vid.xres-8, vid.yres-8-fs*5, 2, vid.fsize, XLAT("y: %1", fts4(mh[1])), 0xC0C0C0, 16);
       displayfr(vid.xres-8, vid.yres-8-fs*4, 2, vid.fsize, XLAT("z: %1", fts4(mh[2])), 0xC0C0C0, 16);
       displayfr(vid.xres-8, vid.yres-8-fs*2, 2, vid.fsize, XLAT("r: %1", fts4(hdist0(mh))), 0xC0C0C0, 16);
-      displayfr(vid.xres-8, vid.yres-8-fs, 2, vid.fsize, XLAT("ϕ: %1°", fts4(-atan2(mh[1], mh[0]) * 360 / 2 / M_PI)), 0xC0C0C0, 16);
+      displayfr(vid.xres-8, vid.yres-8-fs, 2, vid.fsize, XLAT("ϕ: %1°", fts4(-atan2(mh[1], mh[0]) / degree)), 0xC0C0C0, 16);
       }
 
     if(us) {
diff --git a/polygons.cpp b/polygons.cpp
index 2f15fef5..6b2c0b0e 100644
--- a/polygons.cpp
+++ b/polygons.cpp
@@ -1050,7 +1050,7 @@ void dqi_poly::draw() {
         // we should fill the other side
         ld h = atan2(glcoords[0][0], glcoords[0][1]);
         for(int i=0; i<=360; i++) {
-          ld a = i * M_PI / 180 + h;
+          ld a = i * degree + h;
           glcoords.push_back(make_array<GLfloat>(vid.radius * sin(a), vid.radius * vid.stretch * cos(a), stereo::scrdist));
           }
         poly_flags ^= POLY_INVERSE;
diff --git a/rogueviz-graph.cpp b/rogueviz-graph.cpp
index 329ca132..efd80125 100644
--- a/rogueviz-graph.cpp
+++ b/rogueviz-graph.cpp
@@ -170,7 +170,7 @@ void run_snub(int v, int w) {
       hyperpoint f1 = facingdir(hts);
       
       ld scalar = (f|f1);
-      ld alpha = (M_PI - acos(scalar)) * 180 / M_PI;
+      ld alpha = (M_PI - acos(scalar)) / degree;
       sideangles.emplace_back(alpha, T);
       }
     }
diff --git a/rogueviz-pentagonal.cpp b/rogueviz-pentagonal.cpp
index b76d0252..3affa128 100644
--- a/rogueviz-pentagonal.cpp
+++ b/rogueviz-pentagonal.cpp
@@ -164,7 +164,7 @@ void run_snub(int v, int w) {
       hyperpoint f1 = facingdir(hts);
       
       ld scalar = (f|f1);
-      ld alpha = (M_PI - acos(scalar)) * 180 / M_PI;
+      ld alpha = (M_PI - acos(scalar)) / degree;
       sideangles.emplace_back(alpha, T);
       }
     }
diff --git a/rogueviz.cpp b/rogueviz.cpp
index a97a4199..5e77ef0d 100644
--- a/rogueviz.cpp
+++ b/rogueviz.cpp
@@ -356,7 +356,7 @@ namespace anygraph {
       coords.push_back(make_pair(r, alpha));
       if(err < 2) { printf("Error: incorrect format of r/alpha\n"); exit(1); }
   
-      transmatrix h = spin(alpha * 2 * M_PI / 360) * xpush(r);
+      transmatrix h = spin(alpha * degree) * xpush(r);
       
       createViz(id, currentmap->gamestart(), h);
       }