diff --git a/OdeWorld.cc b/OdeWorld.cc
index e20897e..149d210 100644
--- a/OdeWorld.cc
+++ b/OdeWorld.cc
@@ -204,8 +204,18 @@ dGeomID OdeWorld::addPlane(const string & name, bool static_data,
 {
     if (args.size() != 6)
         return 0;
-    float a, b, c, d;
-    /* TODO: find a, b, c, d from args */
+
+    dMatrix3 r;
+    dRFromEulerAngles(r, args[3], args[4], args[5]);
+    dVector3 default_plane_direction = {0, 0, 1, 0};
+    dVector3 rotated_plane_direction;
+    dMultiply0(rotated_plane_direction, default_plane_direction, r, 1, 3, 3);
+
+    float a = rotated_plane_direction[0];
+    float b = rotated_plane_direction[1];
+    float c = rotated_plane_direction[2];
+    float d = a * args[0] + b * args[1] + c * args[2];
+
     dGeomID id = dCreatePlane(m_space, a, b, c, d);
     return id;
 }