From 5678c1cd76e8db6d839afa309a1e1deee1976849 Mon Sep 17 00:00:00 2001
From: Frederic Bouvier <fredfgfs01@free.fr>
Date: Wed, 4 Apr 2012 20:42:05 +0200
Subject: [PATCH] Add a sunlight technique to disable shadows, and avoid shader
 syntax problems with old NV cards

---
 Effects/sunlight.eff           | 71 +++++++++++++++++++++++++++++++++-
 Shaders/sunlight-noshadow.frag | 41 ++++++++++++++++++++
 2 files changed, 111 insertions(+), 1 deletion(-)
 create mode 100644 Shaders/sunlight-noshadow.frag

diff --git a/Effects/sunlight.eff b/Effects/sunlight.eff
index d32d6af79..b685049ed 100644
--- a/Effects/sunlight.eff
+++ b/Effects/sunlight.eff
@@ -1,7 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <PropertyList>
 	<name>Effects/sunlight</name>
-	<technique n="11">
+	<technique n="10">
+		<predicate>
+			<property>/sim/rendering/shadows/enabled</property>
+		</predicate>
 		<pass>
 			<lighting>false</lighting>
 			<depth>
@@ -76,5 +79,71 @@
 			-->
 		</pass>
 	</technique>
+	<technique n="11">
+		<pass>
+			<lighting>false</lighting>
+			<depth>
+				<enabled>false</enabled>
+			</depth>
+			<blend>
+				<source>one</source>
+				<destination>one</destination>
+			</blend>
+			<render-bin>
+				<bin-number>1</bin-number>
+				<bin-name>RenderBin</bin-name>
+			</render-bin>
+			<texture-unit>
+				<unit>0</unit>
+				<type>depth-buffer</type>
+			</texture-unit>
+			<texture-unit>
+				<unit>1</unit>
+				<type>normal-buffer</type>
+			</texture-unit>
+			<texture-unit>
+				<unit>2</unit>
+				<type>diffuse-buffer</type>
+			</texture-unit>
+			<texture-unit>
+				<unit>3</unit>
+				<type>spec-emis-buffer</type>
+			</texture-unit>
+			<program>
+				<vertex-shader>Shaders/sunlight.vert</vertex-shader>
+				<fragment-shader>Shaders/sunlight-noshadow.frag</fragment-shader>
+			</program>
+			<uniform>
+				<name>depth_tex</name>
+				<type>sampler-2d</type>
+				<value type="int">0</value>
+			</uniform>
+			<uniform>
+				<name>normal_tex</name>
+				<type>sampler-2d</type>
+				<value type="int">1</value>
+			</uniform>
+			<uniform>
+				<name>color_tex</name>
+				<type>sampler-2d</type>
+				<value type="int">2</value>
+			</uniform>
+			<uniform>
+				<name>spec_emis_tex</name>
+				<type>sampler-2d</type>
+				<value type="int">3</value>
+			</uniform>
+			<!-- The following uniforms are automatically defined and initialized :
+				- fg_SunAmbientColor
+				- fg_SunDiffuseColor
+				- fg_SunSpecularColor
+				- fg_SunDirection
+				- fg_ProjectionMatrixInverse
+				- fg_ViewMatrixInverse
+				- fg_ViewMatrix
+				- fg_Planes
+			-->
+		</pass>
+	</technique>
 </PropertyList>
 
diff --git a/Shaders/sunlight-noshadow.frag b/Shaders/sunlight-noshadow.frag
new file mode 100644
index 000000000..79f5ea664
--- /dev/null
+++ b/Shaders/sunlight-noshadow.frag
@@ -0,0 +1,41 @@
+uniform mat4 fg_ViewMatrix;
+uniform sampler2D depth_tex;
+uniform sampler2D normal_tex;
+uniform sampler2D color_tex;
+uniform sampler2D spec_emis_tex;
+uniform vec4 fg_SunDiffuseColor;
+uniform vec4 fg_SunSpecularColor;
+uniform vec3 fg_SunDirection;
+uniform vec3 fg_Planes;
+varying vec3 ray;
+void main() {
+    vec2 coords = gl_TexCoord[0].xy;
+    vec4 spec_emis = texture2D( spec_emis_tex, coords );
+    if ( spec_emis.a < 0.1 )
+        discard;
+    vec3 normal;
+    normal.xy = texture2D( normal_tex, coords ).rg * 2.0 - vec2(1.0,1.0);
+    normal.z = sqrt( 1.0 - dot( normal.xy, normal.xy ) );
+    float len = length(normal);
+    normal /= len;
+    vec3 viewDir = normalize(ray);
+    float depth = texture2D( depth_tex, coords ).r;
+    vec3 pos;
+    pos.z = - fg_Planes.y / (fg_Planes.x + depth * fg_Planes.z);
+    pos.xy = viewDir.xy / viewDir.z * pos.z;
+
+    vec4 tint;
+    vec3 lightDir = (fg_ViewMatrix * vec4( fg_SunDirection, 0.0 )).xyz;
+    lightDir = normalize( lightDir );
+    vec3 color = texture2D( color_tex, coords ).rgb;
+    vec3 Idiff = clamp( dot( lightDir, normal ), 0.0, 1.0 ) * color * fg_SunDiffuseColor.rgb;
+    vec3 halfDir = lightDir - viewDir;
+    len = length( halfDir );
+    vec3 Ispec = vec3(0.0);
+    vec3 Iemis = spec_emis.z * color;
+    if (len > 0.0001) {
+        halfDir /= len;
+        Ispec = pow( clamp( dot( halfDir, normal ), 0.0, 1.0 ), spec_emis.y * 255.0 ) * spec_emis.x * fg_SunSpecularColor.rgb;
+    }
+    gl_FragColor = vec4(Idiff + Ispec + Iemis, 1.0);
+}