diff --git a/basegraph.cpp b/basegraph.cpp
index d205568e..68f3375b 100644
--- a/basegraph.cpp
+++ b/basegraph.cpp
@@ -297,8 +297,12 @@ void display_data::set_projection(int ed) {
       }
 
     
-    if(ed) glhr::projection_multiply(glhr::translate(vid.ipd * ed/2, 0, 0));
-  
+    if(ed) {
+      if(pers3)
+        glhr::projection_multiply(glhr::tmtogl(xpush(vid.ipd * ed/2)));
+      else
+        glhr::projection_multiply(glhr::translate(vid.ipd * ed/2, 0, 0));
+      }  
 
     if(pers3) {
       glhr::fog_max(1/sightranges[geometry], darkena(backcolor, 0, 0xFF));
diff --git a/hyper.h b/hyper.h
index 84b67b4c..a0a0a169 100644
--- a/hyper.h
+++ b/hyper.h
@@ -4006,6 +4006,8 @@ namespace glhr {
   
   extern shader_projection new_shader_projection;
   
+  glmatrix tmtogl(const transmatrix& T);
+  
   void set_depthtest(bool b);
   glmatrix translate(ld x, ld y, ld z);
   void color2(color_t color, ld scale = 1);
diff --git a/shaders.cpp b/shaders.cpp
index acd55928..37d3d0b6 100644
--- a/shaders.cpp
+++ b/shaders.cpp
@@ -82,6 +82,14 @@ glmatrix scale(ld x, ld y, ld z) {
   return tmp;
   }
 
+glmatrix tmtogl(const transmatrix& T) {
+  glmatrix tmp;
+  for(int i=0; i<4; i++)
+  for(int j=0; j<4; j++)
+    tmp[i][j] = T[i][j];
+  return tmp;
+  }
+
 glmatrix ortho(ld x, ld y, ld z) {
   return scale(1/x, 1/y, 1/z);
   }