From e4b856805ed1cf7ef751ddcdb0c7fa18b2138595 Mon Sep 17 00:00:00 2001
From: Frederic Bouvier <fredfgfs01@free.fr>
Date: Tue, 17 Apr 2012 09:12:57 +0200
Subject: [PATCH] Make the number of shadow cascades and the range of each
 configurable

---
 Effects/sunlight.eff  |  2 ++
 Shaders/sunlight.frag | 14 +++++++++-----
 preferences.xml       |  5 +++++
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/Effects/sunlight.eff b/Effects/sunlight.eff
index 9905237ca..638c83dfc 100644
--- a/Effects/sunlight.eff
+++ b/Effects/sunlight.eff
@@ -77,6 +77,8 @@
 				- fg_ViewMatrixInverse
 				- fg_ViewMatrix
 				- fg_Planes
+				- fg_ShadowNumber
+				- fg_ShadowDistances
 			-->
 		</pass>
 	</technique>
diff --git a/Shaders/sunlight.frag b/Shaders/sunlight.frag
index 4c616819c..6d453c6ec 100644
--- a/Shaders/sunlight.frag
+++ b/Shaders/sunlight.frag
@@ -8,6 +8,8 @@ uniform vec4 fg_SunDiffuseColor;
 uniform vec4 fg_SunSpecularColor;
 uniform vec3 fg_SunDirection;
 uniform vec3 fg_Planes;
+uniform int fg_ShadowNumber;
+uniform vec4 fg_ShadowDistances;
 varying vec3 ray;
 
 vec3 position( vec3 viewdir, float depth );
@@ -18,18 +20,20 @@ vec4 DynamicShadow( in vec4 ecPosition, out vec4 tint )
     vec4 coords;
     vec2 shift = vec2( 0.0 );
     int index = 4;
-    if (ecPosition.z > -5.0) {
+	float factor = 0.5;
+    if (ecPosition.z > -fg_ShadowDistances.x) {
         index = 1;
+		factor = 1.0;
         tint = vec4(0.0,1.0,0.0,1.0);
-    } else if (ecPosition.z > -50.0) {
+    } else if (ecPosition.z > -fg_ShadowDistances.y && fg_ShadowNumber > 1) {
         index = 2;
         shift = vec2( 0.0, 0.5 );
         tint = vec4(0.0,0.0,1.0,1.0);
-    } else if (ecPosition.z > -512.0) {
+    } else if (ecPosition.z > -fg_ShadowDistances.z && fg_ShadowNumber > 2) {
         index = 3;
         shift = vec2( 0.5, 0.0 );
         tint = vec4(1.0,1.0,0.0,1.0);
-    } else if (ecPosition.z > -10000.0) {
+    } else if (ecPosition.z > -fg_ShadowDistances.w && fg_ShadowNumber > 3) {
         shift = vec2( 0.5, 0.5 );
         tint = vec4(1.0,0.0,0.0,1.0);
     } else {
@@ -39,7 +43,7 @@ vec4 DynamicShadow( in vec4 ecPosition, out vec4 tint )
     coords.t = dot( ecPosition, gl_EyePlaneT[index] );
     coords.p = dot( ecPosition, gl_EyePlaneR[index] );
     coords.q = dot( ecPosition, gl_EyePlaneQ[index] );
-    coords.st *= .5;
+    coords.st *= factor;
     coords.st += shift;
     return coords;
 }
diff --git a/preferences.xml b/preferences.xml
index e3cfde94d..766f57388 100644
--- a/preferences.xml
+++ b/preferences.xml
@@ -182,6 +182,11 @@ Started September 2000 by David Megginson, david@megginson.com
 				<debug type="bool"
 							 userarchive="y">false</debug>
 				<map-size type="int">4096</map-size>
+				<num-cascades type="int">4</num-cascades>
+				<cascade-far-m index="0" type="float">5.0</cascade-far-m>
+				<cascade-far-m index="1" type="float">50.0</cascade-far-m>
+				<cascade-far-m index="2" type="float">500.0</cascade-far-m>
+				<cascade-far-m index="3" type="float">5000.0</cascade-far-m>
 			</shadows>
 			<shader-experimental type="bool"
 													 userarchive="y">false</shader-experimental>