rug:: fixed moving the rug in Crystal

config.cpp

@@ -3554,6 +3554,7 @@ EX int config3 = addHook(hooks_configfile, 100, [] {
   param_b(vid.fixed_facing, "fixed facing", 0);
   param_f(vid.fixed_facing_dir, "fixed facing dir", 90);
   param_b(vid.fixed_yz, "fixed YZ", true);
+  param_b(rug::rug_fixed_yz, "rug fixed YZ", false);
   param_b(frustum_culling, "frustum_culling");
   param_b(numerical_minefield, "numerical_minefield")
   -> editable("toggle numerical display", 'n');

control.cpp

@@ -572,7 +572,7 @@ EX void full_rotate_camera(int dir, ld val) {
   else if(GDIM == 3 && rshiftclick)
     shift_view(ctangent(dir, -val * camera_speed)), didsomething = true, playermoved = false; /* -val because shift reverses */
   #if CAP_CRYSTAL && CAP_RUG
-  else if(rug::rug_control() && rug::in_crystal())
+  else if(rug::rug_control() && rug::in_crystal() && rug::crystal_rotation)
     crystal::apply_rotation(cspin(dir, 2, val * camera_rot_speed));
   #endif
   else if(GDIM == 3) {

crystal.cpp

@@ -1164,6 +1164,7 @@ EX void flip_z() {
 hyperpoint coord_to_flat(ldcoord co, int dim = 3) {
   auto& cs = crystal_map()->cs;
   hyperpoint res = Hypc;
+  res[3] = 1;
   co = co - rug_center;
   for(int a=0; a<cs.dim; a++)
     for(int b=0; b<dim; b++)

rug.cpp

@@ -21,6 +21,8 @@ EX namespace rug {
 
 EX bool mouse_control_rug = false;
 
+EX bool crystal_rotation = false;
+
 EX transmatrix rugView;
 
 EX ld lwidth = 2;
@@ -1122,11 +1124,13 @@ EX GLuint alternate_texture;
 
 EX bool rug_control() { return rug::rugged; }
 
+EX bool rug_fixed_yz = false;
+
 #if HDR
 
 struct using_rugview {
-  using_rugview() { if(rug_control()) swap(View, rugView), swap(geometry, gwhere); }
-  ~using_rugview() { if(rug_control()) swap(View, rugView), swap(geometry, gwhere); }
+  using_rugview() { if(rug_control()) swap(View, rugView), swap(geometry, gwhere), swap(vid.fixed_yz, rug_fixed_yz); }
+  ~using_rugview() { if(rug_control()) swap(View, rugView), swap(geometry, gwhere), swap(vid.fixed_yz, rug_fixed_yz); }
   };
 
 #endif
@@ -1629,6 +1633,8 @@ EX void show_crystal_settings() {
   surface::shape_option(surface::dsCrystal, 'u', false);
   #endif
 
+  dialog::addBoolItem_action("high-dim crystal rotation", crystal_rotation, 'r');
+
   if(rug::in_crystal()) {
     dialog::addItem("next home orientation", 'h');
     dialog::add_action(crystal::next_home_orientation);