diff --git a/Effects/model-interior.eff b/Effects/model-interior.eff
index fcc14c4b8..af473b0f8 100644
--- a/Effects/model-interior.eff
+++ b/Effects/model-interior.eff
@@ -5,7 +5,7 @@
   <inherits-from>Effects/model-default</inherits-from>
 
   <parameters>
-  <texture n="4">
+  	<texture n="4">
 		<type>cubemap</type>
 		<images>
 			<positive-x>Aircraft/Generic/Effects/CubeMaps/real.fair-sky/fair-sky_px.png</positive-x>
@@ -15,10 +15,16 @@
 			<positive-z>Aircraft/Generic/Effects/CubeMaps/real.fair-sky/fair-sky_pz.png</positive-z>
 			<negative-z>Aircraft/Generic/Effects/CubeMaps/real.fair-sky/fair-sky_nz.png</negative-z>
 		</images>
-		</texture>
-		<opacity-cube-center type="vec3d" n="0"> 0.0 0.0 0.0</opacity-cube-center>
-		<opacity-cube-scale type="vec3d" n="0"> 1.0 1.0 1.0</opacity-cube-scale>
-		<opacity-cube-angle type="float">0.0</opacity-cube-angle>
+	</texture>
+	<opacity-cube-center type="vec3d" n="0"> 0.0 0.0 0.0</opacity-cube-center>
+	<opacity-cube-scale type="vec3d" n="0"> 1.0 1.0 1.0</opacity-cube-scale>
+	<opacity-cube-angle type="float">0.0</opacity-cube-angle>
+	<implicit-lightmap-enabled type="int">0</implicit-lightmap-enabled>
+	<implicit-lightmap-tag-color type="vec3d">1.0 1.0 1.0</implicit-lightmap-tag-color>
+	<implicit-lightmap-threshold-low type="float">0.5</implicit-lightmap-threshold-low>
+	<implicit-lightmap-threshold-high type="float">1.5</implicit-lightmap-threshold-high>
+	<implicit-lightmap-emit-color type="vec3d">1.0 1.0 1.0</implicit-lightmap-emit-color>
+	<implicit-lightmap-intensity type="float">0.0</implicit-lightmap-intensity>
   </parameters>
 
   <technique n="4">
@@ -154,6 +160,31 @@
         <name>angle</name>
         <type>float</type>
         <value><use>opacity-cube-angle</use></value>
+     </uniform>
+     <uniform>
+        <name>tag_color</name>
+        <type>float-vec3</type>
+        <value><use>implicit-lightmap-tag-color</use></value>
+     </uniform>
+     <uniform>
+        <name>emit_color</name>
+        <type>float-vec3</type>
+        <value><use>implicit-lightmap-emit-color</use></value>
+     </uniform>
+     <uniform>
+        <name>threshold_low</name>
+        <type>float</type>
+        <value><use>implicit-lightmap-threshold-low</use></value>
+     </uniform>
+     <uniform>
+        <name>threshold_high</name>
+        <type>float</type>
+        <value><use>implicit-lightmap-threshold-high</use></value>
+     </uniform>
+    <uniform>
+        <name>emit_intensity</name>
+        <type>float</type>
+        <value><use>implicit-lightmap-intensity</use></value>
      </uniform>
       <uniform>
         <name>texture</name>
@@ -180,6 +211,11 @@
         <type>int</type>
         <value><use>tquality_level</use></value>
       </uniform>
+      <uniform>
+        <name>implicit_lightmap_enabled</name>
+        <type>int</type>
+        <value><use>implicit-lightmap-enabled</use></value>
+      </uniform>
     </pass>
   </technique>
 
diff --git a/Shaders/model-interior-ALS-base.frag b/Shaders/model-interior-ALS-base.frag
index 3d510ff1b..d4407c738 100644
--- a/Shaders/model-interior-ALS-base.frag
+++ b/Shaders/model-interior-ALS-base.frag
@@ -24,14 +24,20 @@ uniform float overcast;
 uniform float eye_alt;
 uniform float cloud_self_shading;
 uniform float angle;
+uniform float threshold_low;
+uniform float threshold_high;
+uniform float emit_intensity;
 
 uniform vec3 offset_vec;
 uniform vec3 scale_vec;
+uniform vec3 tag_color;
+uniform vec3 emit_color;
     
 
 uniform int quality_level;
 uniform int tquality_level;
 uniform int use_searchlight;
+uniform int implicit_lightmap_enabled;
 
 
 const float EarthRadius = 5800000.0;
@@ -145,9 +151,19 @@ void main()
     texel = texture2D(texture, gl_TexCoord[0].st);
     fragColor = color * texel + specular;
 
-    //fragColor.rgb = vec3(1.0,1.0,1.0) * (1.0 - opacity.a);
+   // implicit lightmap - the user gets to select 
 
+   if (implicit_lightmap_enabled == 1)
+	{
+	float cdiff = (length(texel.rgb - tag_color));
+	float enhance = 1.0 - smoothstep(threshold_low, threshold_high, cdiff); 
+	fragColor.rgb = fragColor.rgb + enhance * emit_color * emit_intensity;
+	}
+
+
+	
 
 gl_FragColor = fragColor;
+
 }