From 662d782f98189d76599e0f8cc109f9aebd37b1ba Mon Sep 17 00:00:00 2001
From: Thorsten Renk <thorsten@science-and-fiction.org>
Date: Fri, 3 Mar 2017 19:50:13 +0200
Subject: [PATCH] Groundwork for ALS g-force blackout filter, WIP

---
 Effects/agriculture.eff     | 11 ++++++
 Effects/airfield.eff        | 10 ++++++
 Effects/building.eff        |  4 +--
 Effects/cloud-static.eff    | 12 +++++++
 Effects/cloud.eff           | 12 +++++++
 Effects/dirt-runway.eff     | 10 ++++++
 Effects/model-combined.eff  | 12 +++++++
 Effects/model-default.eff   | 12 +++++++
 Effects/model-interior.eff  | 20 +++++++++++
 Effects/rain-layer.eff      | 12 +++++++
 Effects/rock.eff            | 10 ++++++
 Effects/runway.eff          | 10 ++++++
 Effects/skydome.eff         | 12 +++++++
 Effects/terrain-default.eff | 32 ++++++++++++++++++
 Effects/tree.eff            | 67 +++++++++++++++++++++++++++++++++++++
 Effects/urban.eff           | 20 +++++++++++
 Effects/water-inland.eff    | 23 ++++++++++++-
 Effects/water.eff           | 21 ++++++++++++
 Shaders/filters-ALS.frag    | 38 ++++++++++++++++++++-
 defaults.xml                |  3 ++
 gui/dialogs/als-filters.xml | 41 +++++++++++++++++++++--
 21 files changed, 386 insertions(+), 6 deletions(-)

diff --git a/Effects/agriculture.eff b/Effects/agriculture.eff
index 041f920ea..debd89739 100644
--- a/Effects/agriculture.eff
+++ b/Effects/agriculture.eff
@@ -457,6 +457,17 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
+      <!-- cloud shadows -->
       <uniform>
         <name>cloudpos1_x</name>
         <type>float</type>
diff --git a/Effects/airfield.eff b/Effects/airfield.eff
index 0a348fdc8..a516d595b 100644
--- a/Effects/airfield.eff
+++ b/Effects/airfield.eff
@@ -327,6 +327,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <!-- cloud shadows -->
       <uniform>
         <name>cloudpos1_x</name>
diff --git a/Effects/building.eff b/Effects/building.eff
index 91afa9bee..dcd8062fc 100644
--- a/Effects/building.eff
+++ b/Effects/building.eff
@@ -98,8 +98,8 @@
 		<terminator><use>/environment/terminator-relative-position-m</use></terminator>
 		<fogtype><use>/sim/rendering/shaders/skydome</use></fogtype>
 		<terrain_alt><use>/environment/mean-terrain-elevation-m</use></terrain_alt>
-    <overcast><use>/rendering/scene/overcast</use></overcast>
-    <eye_alt><use>/sim/rendering/eye-altitude-m</use></eye_alt>
+    	        <overcast><use>/rendering/scene/overcast</use></overcast>
+                <eye_alt><use>/sim/rendering/eye-altitude-m</use></eye_alt>
 		<snow_level><use>/environment/snow-level-m</use></snow_level>
 		<dust_cover_factor><use>/environment/surface/dust-cover-factor</use></dust_cover_factor>
 		<fogtype><use>/sim/rendering/shaders/skydome</use></fogtype>
diff --git a/Effects/cloud-static.eff b/Effects/cloud-static.eff
index b7a9f0e9a..d2f6d44c0 100644
--- a/Effects/cloud-static.eff
+++ b/Effects/cloud-static.eff
@@ -12,6 +12,8 @@
     <gamma><use>/sim/rendering/als-filters/gamma</use></gamma>
     <brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
     <delta_T><use>/environment/surface/delta-T-cloud</use></delta_T>
+    <fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     <use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     <use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
     <display_xsize><use>/sim/startup/xsize</use></display_xsize>
@@ -124,6 +126,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>display_xsize</name>
         <type>int</type>
diff --git a/Effects/cloud.eff b/Effects/cloud.eff
index 647d8773b..200e7b93e 100644
--- a/Effects/cloud.eff
+++ b/Effects/cloud.eff
@@ -21,6 +21,8 @@
     <gamma><use>/sim/rendering/als-filters/gamma</use></gamma>
     <brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
     <delta_T><use>/environment/surface/delta-T-cloud</use></delta_T>
+    <fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     <use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     <use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
     <display_xsize><use>/sim/startup/xsize</use></display_xsize>
@@ -182,6 +184,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>display_xsize</name>
         <type>int</type>
diff --git a/Effects/dirt-runway.eff b/Effects/dirt-runway.eff
index 880e04fde..0fa5f3399 100644
--- a/Effects/dirt-runway.eff
+++ b/Effects/dirt-runway.eff
@@ -362,6 +362,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <!-- cloud shadows -->
       <uniform>
         <name>cloudpos1_x</name>
diff --git a/Effects/model-combined.eff b/Effects/model-combined.eff
index 953e58425..4814d3648 100644
--- a/Effects/model-combined.eff
+++ b/Effects/model-combined.eff
@@ -972,6 +972,18 @@ please see Docs/README.model-combined.eff for documentation
         			<type>float</type>
         			<value><use>delta_T</use></value>
       			   </uniform>
+			   <uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			   </uniform>
+			   <uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			   </uniform>
+
+			  <!-- cloud shadows -->
  			   <uniform>
        				  <name>cloudpos1_x</name>
         			  <type>float</type>
diff --git a/Effects/model-default.eff b/Effects/model-default.eff
index 86ffb87ea..1ad02e801 100644
--- a/Effects/model-default.eff
+++ b/Effects/model-default.eff
@@ -30,6 +30,8 @@
     		<gamma><use>/sim/rendering/als-filters/gamma</use></gamma>
     		<brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
     		<delta_T><use>/environment/surface/delta-T-structure</use></delta_T>
+		<fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    	        <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     		<use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     		<use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
 		<display_xsize><use>/sim/startup/xsize</use></display_xsize>
@@ -221,6 +223,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>view_pitch_offset</name>
         <type>float</type>
diff --git a/Effects/model-interior.eff b/Effects/model-interior.eff
index bddc8f2b6..1001e77c9 100644
--- a/Effects/model-interior.eff
+++ b/Effects/model-interior.eff
@@ -387,6 +387,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>texture</name>
         <type>sampler-2d</type>
@@ -694,6 +704,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>texture</name>
         <type>sampler-2d</type>
diff --git a/Effects/rain-layer.eff b/Effects/rain-layer.eff
index cef0f27ed..b33b69834 100644
--- a/Effects/rain-layer.eff
+++ b/Effects/rain-layer.eff
@@ -16,6 +16,8 @@
     <gamma><use>/sim/rendering/als-filters/gamma</use></gamma>
     <brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
     <delta_T><use>/environment/surface/delta-T-cloud</use></delta_T>
+    <fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     <use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     <use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
     <display_xsize><use>/sim/startup/xsize</use></display_xsize>
@@ -147,6 +149,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>display_xsize</name>
         <type>int</type>
diff --git a/Effects/rock.eff b/Effects/rock.eff
index 1cfbb5ec4..80fe36464 100644
--- a/Effects/rock.eff
+++ b/Effects/rock.eff
@@ -325,6 +325,16 @@
         <name>delta_T</name>
         <type>float</type>
         <value><use>delta_T</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
       </uniform>
 	<!-- cloud shadows -->
       <uniform>
diff --git a/Effects/runway.eff b/Effects/runway.eff
index 4cad33165..b3dec7a62 100644
--- a/Effects/runway.eff
+++ b/Effects/runway.eff
@@ -569,6 +569,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <!-- cloud shadows -->
       <uniform>
         <name>cloudpos1_x</name>
diff --git a/Effects/skydome.eff b/Effects/skydome.eff
index 90859d566..412288cfc 100644
--- a/Effects/skydome.eff
+++ b/Effects/skydome.eff
@@ -38,6 +38,8 @@
     <brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
     <use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     <use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
+    <fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     <delta_T>-50.0</delta_T>
     <air_pollution><use>/environment/air-pollution-norm</use></air_pollution>
   </parameters>
@@ -191,6 +193,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>use_filtering</name>
         <type>bool</type>
diff --git a/Effects/terrain-default.eff b/Effects/terrain-default.eff
index 64fe4d57e..2e85cd87d 100644
--- a/Effects/terrain-default.eff
+++ b/Effects/terrain-default.eff
@@ -134,6 +134,8 @@
     <use_filtering><use>/sim/rendering/als-filters/use-filtering</use></use_filtering>
     <gamma><use>/sim/rendering/als-filters/gamma</use></gamma>
     <brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
+    <fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     <use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     <use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
     <cloudpos1_x><use>/local-weather/cloud-shadows/cloudpos-x[0]</use></cloudpos1_x>
@@ -518,6 +520,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <!-- cloud shadows -->
       <uniform>
         <name>cloudpos1_x</name>
@@ -1061,6 +1073,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>display_xsize</name>
         <type>int</type>
@@ -1292,6 +1314,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
       <uniform>
         <name>display_xsize</name>
         <type>int</type>
diff --git a/Effects/tree.eff b/Effects/tree.eff
index 691b65b6d..2488ba9e6 100644
--- a/Effects/tree.eff
+++ b/Effects/tree.eff
@@ -60,6 +60,8 @@
 		<use_filtering><use>/sim/rendering/als-filters/use-filtering</use></use_filtering>
     		<gamma><use>/sim/rendering/als-filters/gamma</use></gamma>
     		<brightness><use>/sim/rendering/als-filters/brightness</use></brightness>
+		<fact_grey><use>/sim/rendering/als-filters/grey-factor</use></fact_grey>
+    	        <fact_black><use>/sim/rendering/als-filters/black-factor</use></fact_black>
     		<use_night_vision><use>/sim/rendering/als-filters/use-night-vision</use></use_night_vision>
     		<use_IR_vision><use>/sim/rendering/als-filters/use-IR-vision</use></use_IR_vision>
     		<delta_T><use>/environment/surface/delta-T-vegetation</use></delta_T>
@@ -304,6 +306,16 @@
         <name>delta_T</name>
         <type>float</type>
         <value><use>delta_T</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
       </uniform>
 	<!-- cloud shadows -->
       <uniform>
@@ -794,6 +806,16 @@
         <type>float</type>
         <value><use>delta_T</use></value>
       </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
      <!-- cloud shadows -->
       <uniform>
         <name>cloudpos1_x</name>
@@ -1242,6 +1264,51 @@
         <type>float</type>
         <value><use>landing_light3_offset</use></value>
       </uniform>
+      <!-- filtering -->
+
+      <uniform>
+        <name>gamma</name>
+        <type>float</type>
+        <value><use>gamma</use></value>
+      </uniform>
+      <uniform>
+        <name>brightness</name>
+        <type>float</type>
+        <value><use>brightness</use></value>
+      </uniform>
+      <uniform>
+        <name>use_night_vision</name>
+        <type>bool</type>
+        <value><use>use_night_vision</use></value>
+      </uniform>
+      <uniform>
+        <name>use_IR_vision</name>
+        <type>bool</type>
+        <value><use>use_IR_vision</use></value>
+      </uniform>
+      <uniform>
+        <name>use_filtering</name>
+        <type>bool</type>
+        <value><use>use_filtering</use></value>
+      </uniform>
+      <uniform>
+        <name>delta_T</name>
+        <type>float</type>
+        <value><use>delta_T</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_grey</name>
+        <type>float</type>
+        <value><use>fact_grey</use></value>
+      </uniform>
+      <uniform>
+        <name>fact_black</name>
+        <type>float</type>
+        <value><use>fact_black</use></value>
+      </uniform>
+
+      <!-- cloud shadows -->
+
       <uniform>
         <name>cloudpos1_x</name>
         <type>float</type>
diff --git a/Effects/urban.eff b/Effects/urban.eff
index 41da34776..d3229238b 100644
--- a/Effects/urban.eff
+++ b/Effects/urban.eff
@@ -508,6 +508,16 @@
         			<type>float</type>
         			<value><use>delta_T</use></value>
       			   </uniform>
+			   <uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			   </uniform>
+			   <uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			   </uniform>
 			<!-- cloud shadows -->
 			   <uniform>
        				  <name>cloudpos1_x</name>
@@ -1064,6 +1074,16 @@
         			<type>float</type>
         			<value><use>delta_T</use></value>
       			   </uniform>
+			   <uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			   </uniform>
+			   <uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			   </uniform>
 			<!-- cloud shadows -->
 			   <uniform>
        				  <name>cloudpos1_x</name>
diff --git a/Effects/water-inland.eff b/Effects/water-inland.eff
index 684594e13..79343c11c 100644
--- a/Effects/water-inland.eff
+++ b/Effects/water-inland.eff
@@ -647,6 +647,17 @@
         			<type>float</type>
         			<value><use>delta_T</use></value>
       			</uniform>
+		      	<uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			</uniform>
+			<uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			</uniform>
+			<!-- cloud shadows -->
 			<uniform>
        				<name>cloudpos1_x</name>
         			<type>float</type>
@@ -1305,7 +1316,17 @@
         			<name>delta_T</name>
         			<type>float</type>
         			<value><use>delta_T</use></value>
-      			</uniform>	
+      			</uniform>
+		      	<uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			</uniform>
+			<uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			</uniform>	
 			<!-- sea colors -->
 			<uniform>
 				<name>sea_r</name>
diff --git a/Effects/water.eff b/Effects/water.eff
index afe517c11..03a96084c 100644
--- a/Effects/water.eff
+++ b/Effects/water.eff
@@ -641,6 +641,17 @@
         			<type>float</type>
         			<value><use>delta_T</use></value>
       			</uniform>
+		      	<uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			</uniform>
+			<uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			</uniform>
+			<!-- cloud shadows -->
 			<uniform>
        				<name>cloudpos1_x</name>
         			<type>float</type>
@@ -1304,6 +1315,16 @@
         			<type>float</type>
         			<value><use>delta_T</use></value>
       			</uniform>
+		      	<uniform>
+				<name>fact_grey</name>
+				<type>float</type>
+				<value><use>fact_grey</use></value>
+			</uniform>
+			<uniform>
+				<name>fact_black</name>
+				<type>float</type>
+				<value><use>fact_black</use></value>
+			</uniform>
 			<!-- sea colors -->
 			<uniform>
 				<name>sea_r</name>
diff --git a/Shaders/filters-ALS.frag b/Shaders/filters-ALS.frag
index 812f4deed..1bb63a2b3 100644
--- a/Shaders/filters-ALS.frag
+++ b/Shaders/filters-ALS.frag
@@ -10,6 +10,8 @@ uniform float gamma;
 uniform float brightness;
 uniform float delta_T;
 uniform float osg_SimulationTime;
+uniform float fact_grey;
+uniform float fact_black;
 
 uniform bool use_filtering;
 uniform bool use_night_vision;
@@ -64,6 +66,40 @@ return vec3 (0.7, 0.7, 0.7) * gain;
 
 }
 
+
+
+vec3 g_force (in vec3 color) {
+
+vec2 center = vec2 (float(display_xsize) * 0.5, float(display_ysize) *  0.5);
+
+float greyout_band_width = 0.2;
+float blackout_band_width = 0.3;
+
+float f_grey = 1.0 - fact_grey;
+
+float greyout = smoothstep( f_grey * display_ysize, (f_grey + greyout_band_width) * display_ysize, length(gl_FragCoord.xy -center));
+
+float tgt_brightness = (1.0 - 0.5 * greyout);
+
+float noise = Noise2D( vec2 (gl_FragCoord.x + 100.0 * osg_SimulationTime,  
+gl_FragCoord.y + 300.0 * osg_SimulationTime), 8.0);
+
+float f_black = 1.0 - fact_black;
+
+noise *= (1.0 - smoothstep(0.0, 0.5, f_black));
+
+color = mix(color, vec3 (1.0, 1.0, 1.0) * mix(length(color),  
+tgt_brightness, greyout)  , 0.9* greyout + 0.6 * noise);
+color *= tgt_brightness;
+
+float blackout = 1.0 - smoothstep( f_black * display_ysize, (f_black + blackout_band_width) * display_ysize, length(gl_FragCoord.xy -center));
+
+color *= blackout;
+
+return color;
+
+}
+
 vec3 filter_combined (in vec3 color) {
 
 if (use_filtering == false)
@@ -71,7 +107,7 @@ if (use_filtering == false)
 	return color;
 	}
 
-
+color = g_force(color);
 
 
 if (use_night_vision)
diff --git a/defaults.xml b/defaults.xml
index f2af7f5e6..b6173319a 100644
--- a/defaults.xml
+++ b/defaults.xml
@@ -363,6 +363,9 @@ Started September 2000 by David Megginson, david@megginson.com
  	 <brightness type="float">1.0</brightness>
 	 <use-night-vision type="bool">false</use-night-vision>
 	 <use-IR-vision type="bool">false</use-IR-vision>
+	 <use-normal-filters type="bool">true</use-normal-filters>
+	 <grey-factor type="float">0.0</grey-factor>
+	 <black-factor type="float">0.0</black-factor>
       </als-filters>
 
       <scenery-path-suffix>
diff --git a/gui/dialogs/als-filters.xml b/gui/dialogs/als-filters.xml
index 74448bcc7..ad71544f1 100644
--- a/gui/dialogs/als-filters.xml
+++ b/gui/dialogs/als-filters.xml
@@ -85,6 +85,33 @@
 		<group>
 			<layout>hbox</layout>
 
+			<radio>
+				<halign>left</halign>
+				<label>Normal</label>
+				<live>true</live>
+				<property>/sim/rendering/als-filters/use-normal-filters</property>
+				<enable>
+					<property>/sim/rendering/shaders/skydome</property>
+					<property>/sim/rendering/als-filters/use-filtering</property>
+				</enable>
+				<binding>
+					<command>property-assign</command>
+					<property>/sim/rendering/als-filters/use-night-vision</property>
+					<value type="bool">false</value>
+				</binding>
+				<binding>
+					<command>property-assign</command>
+					<property>/sim/rendering/als-filters/use-IR-vision</property>
+					<value type="bool">false</value>
+				</binding>
+				<binding>
+					<command>property-assign</command>
+					<property>/sim/rendering/als-filters/use-normal-filters</property>
+					<value type="bool">true</value>
+				</binding>
+			</radio>
+
+
 			<radio>
 				<halign>left</halign>
 				<label>Night vision</label>
@@ -95,10 +122,15 @@
 					<property>/sim/rendering/als-filters/use-filtering</property>
 				</enable>
 				<binding>
-					<command>property-toggle</command>
+					<command>property-assign</command>
 					<property>/sim/rendering/als-filters/use-night-vision</property>
 					<value type="bool">true</value>
 				</binding>
+				<binding>
+					<command>property-assign</command>
+					<property>/sim/rendering/als-filters/use-normal-filters</property>
+					<value type="bool">false</value>
+				</binding>
 				<binding>
 					<command>property-assign</command>
 					<property>/sim/rendering/als-filters/use-IR-vision</property>
@@ -116,7 +148,7 @@
 					<property>/sim/rendering/als-filters/use-filtering</property>
 				</enable>
 				<binding>
-					<command>property-toggle</command>
+					<command>property-assign</command>
 					<property>/sim/rendering/als-filters/use-IR-vision</property>
 					<value type="bool">true</value>
 				</binding>
@@ -125,6 +157,11 @@
 					<property>/sim/rendering/als-filters/use-night-vision</property>
 					<value type="bool">false</value>
 				</binding>
+				<binding>
+					<command>property-assign</command>
+					<property>/sim/rendering/als-filters/use-normal-filters</property>
+					<value type="bool">false</value>
+				</binding>
 			</radio>
 
 		</group>