diff --git a/extra/jamshred/gl/gl.factor b/extra/jamshred/gl/gl.factor
index 58e2b1f882..fe2009201f 100644
--- a/extra/jamshred/gl/gl.factor
+++ b/extra/jamshred/gl/gl.factor
@@ -51,9 +51,9 @@ IN: jamshred.gl
     GL_LIGHT0 glEnable
     GL_FOG glEnable
     GL_FOG_DENSITY 0.09 glFogf
+    GL_FRONT GL_AMBIENT_AND_DIFFUSE glColorMaterial
     GL_COLOR_MATERIAL glEnable
-    GL_FRONT_AND_BACK GL_AMBIENT_AND_DIFFUSE glColorMaterial
-    GL_LIGHT0 GL_POSITION F{ 0.0 0.0 -3.0 1.0 } >c-float-array glLightfv
+    GL_LIGHT0 GL_POSITION F{ 0.0 0.0 0.0 1.0 } >c-float-array glLightfv
     GL_LIGHT0 GL_AMBIENT F{ 0.2 0.2 0.2 1.0 } >c-float-array glLightfv
     GL_LIGHT0 GL_DIFFUSE F{ 1.0 1.0 1.0 1.0 } >c-float-array glLightfv
     GL_LIGHT0 GL_SPECULAR F{ 1.0 1.0 1.0 1.0 } >c-float-array glLightfv ;
diff --git a/extra/jamshred/jamshred.factor b/extra/jamshred/jamshred.factor
index dd83efe824..078a23f5db 100755
--- a/extra/jamshred/jamshred.factor
+++ b/extra/jamshred/jamshred.factor
@@ -21,9 +21,9 @@ M: jamshred-gadget draw-gadget* ( gadget -- )
     dup jamshred>> quit>> [
         drop
     ] [
-        dup [ jamshred>> jamshred-update ]
-        [ relayout-1 ] bi
-        yield jamshred-loop
+        [ jamshred>> jamshred-update ]
+        [ relayout-1 ]
+        [ yield jamshred-loop ] tri
     ] if ;
 
 : fullscreen ( gadget -- )
@@ -45,7 +45,7 @@ M: jamshred-gadget ungraft* ( gadget -- )
     <jamshred> >>jamshred drop ;
 
 : pix>radians ( n m -- theta )
-    2 / / pi 2 * * ;
+    / pi 4 * * ; ! 2 / / pi 2 * * ;
 
 : x>radians ( x gadget -- theta )
     #! translate motion of x pixels to an angle