diff --git a/shader/wallLight.frag b/shader/wallLight.frag
new file mode 100644
index 000000000..6721a2496
--- /dev/null
+++ b/shader/wallLight.frag
@@ -0,0 +1,10 @@
+#version 430 core
+in vec2 vDistField;
+in float vLum;
+out vec4 fColor;
+
+void main()
+{
+  float l = dot(vDistField,vDistField);
+  fColor = vec4 (pow(1 - l,2),0,0,1);
+}
diff --git a/shader/wallLight.geom b/shader/wallLight.geom
new file mode 100644
index 000000000..51474aea1
--- /dev/null
+++ b/shader/wallLight.geom
@@ -0,0 +1,55 @@
+#version 430 core
+layout (lines) in;
+layout (triangle_strip, max_vertices = 14) out;
+
+in vec4 vBackPoss[];
+uniform vec2 lightPos;
+uniform mat4 worldMat;
+
+void emitLine (vec2 pa)
+{
+    gl_Position = vec4 (pa, 0, 1);
+    EmitVertex();
+    gl_Position = vec4 (pa + (200 * (pa - lightPos)), 0 , 1);
+    EmitVertex();
+}
+
+float isLHS (vec2 startV, vec2 testV)
+{
+    return sign( -startV.x * testV.y + startV.y * testV.x);
+}
+
+void main()
+{
+  vec4 frontL4 = worldMat * vec4(gl_in[0].gl_Position.xy, 0 ,1);
+  vec4 frontR4 = worldMat * vec4(gl_in[0].gl_Position.zw, 0 ,1);
+  vec2 frontL = frontL4.xy;
+  vec2 frontR = frontR4.xy;
+  vec4 backR4 = worldMat * vec4(vBackPoss[0].xy, 0 ,1);
+  vec4 backL4 = worldMat * vec4(vBackPoss[0].zw, 0 ,1);
+  vec2 backL = backL4.xy;
+  vec2 backR = backR4.xy;
+
+//    if (isLHS( lightPos - frontL, frontR - frontL) < 0)
+//  //  if (isLHS( lightPos - backL, backR - backL) < 0)
+//    {
+//  //  emitLine (frontL);
+//  //  emitLine (backL);
+//  //  emitLine (frontL);
+//  //  emitLine (frontR);
+//  //  emitLine (backR);
+//  //  emitLine (frontR);
+//  
+//    emitLine (backR);
+//    emitLine (backL);
+//    }
+//    else
+//    {
+//    emitLine (backR);
+//    emitLine (backL);
+//    }
+
+    emitLine (frontR);
+    emitLine (frontL);
+  EndPrimitive();
+}
diff --git a/shader/wallLight.vert b/shader/wallLight.vert
new file mode 100644
index 000000000..c708455f3
--- /dev/null
+++ b/shader/wallLight.vert
@@ -0,0 +1,24 @@
+#version 430 core
+layout (location = 0) in vec3 pos;
+
+out vec2 vDistField;
+out float vLum;
+
+uniform mat4 worldMat;
+uniform vec4 lightPosRadLum;
+
+mat4 perspective =  
+    mat4 (1,0,0,0
+         ,0,1,0,0
+         ,0,0,1,1
+         ,0,0,0,1
+         ) ;
+void main()
+{
+  float r = lightPosRadLum.z ;
+  float x = lightPosRadLum.x ;
+  float y = lightPosRadLum.y ;
+  gl_Position = perspective * worldMat * vec4(pos, 1);
+  vDistField = vec2 ( (pos.x - x)/r , (pos.y - y)/(r*100) ) ;
+  vLum = lightPosRadLum.w;
+}