diff --git a/shader/wall/texture.geom b/shader/wall/texture.geom
index 5699bc0a0..1b9d5305d 100644
--- a/shader/wall/texture.geom
+++ b/shader/wall/texture.geom
@@ -18,13 +18,17 @@ void main()
   vec4 p4 = vec4 (p2.xy,100,1);
   vec2 d = vec2(p1.xy - p2.xy);
   vec4 norm = vec4( d.y, -d.x, 0, 0);
-  gNorm = p1 - norm;
-  gPos = p1; tPos = vec2 ( 1,-1) ; gl_Position = vec4(theMat * p1); EmitVertex();
-  gNorm = p1 - norm;
-  gPos = p3; tPos = vec2 ( 1, 1) ; gl_Position = vec4(theMat * p3); EmitVertex();
-  gNorm = p1 - norm;
-  gPos = p2; tPos = vec2 (-1,-1) ; gl_Position = vec4(theMat * p2); EmitVertex();
-  gNorm = p1 - norm;
-  gPos = p4; tPos = vec2 (-1, 1) ; gl_Position = vec4(theMat * p4); EmitVertex();
+  gPos = p1; tPos = vec2 ( 1,-1) ; gl_Position = vec4(theMat * p1); 
+  gNorm = gPos - norm;
+  EmitVertex();
+  gPos = p3; tPos = vec2 ( 1, 1) ; gl_Position = vec4(theMat * p3); 
+  gNorm = gPos - norm;
+  EmitVertex();
+  gPos = p2; tPos = vec2 (-1,-1) ; gl_Position = vec4(theMat * p2); 
+  gNorm = gPos - norm;
+  EmitVertex();
+  gPos = p4; tPos = vec2 (-1, 1) ; gl_Position = vec4(theMat * p4); 
+  gNorm = gPos - norm;
+  EmitVertex();
   EndPrimitive();
 }