From df35c11af249561d4f2e1609a14acf3c29fca5c1 Mon Sep 17 00:00:00 2001
From: Thorsten Renk <thorsten.i.renk@jyu.fi>
Date: Mon, 15 Apr 2013 14:29:04 +0300
Subject: [PATCH] Packice overlay and water color variations for high quality
 water shader in Atmospheric Light Scattering

---
 Effects/water.eff                    |  38 +++++++++
 Environment/environment.xml          |   3 +
 Shaders/water_lightfield.frag        | 110 ++++++++++++++++++++++++++-
 Shaders/water_lightfield.vert        |   4 +-
 gui/dialogs/environment-settings.xml |  82 ++++++++++++++++----
 5 files changed, 218 insertions(+), 19 deletions(-)

diff --git a/Effects/water.eff b/Effects/water.eff
index 9629e9150..61f9bd7c0 100644
--- a/Effects/water.eff
+++ b/Effects/water.eff
@@ -45,6 +45,13 @@
 			<wrap-t>repeat</wrap-t>
 			<internal-format>normalized</internal-format>
 		</texture>
+		<texture n="10">
+			<image>Textures.high/Terrain/packice-overlay.png</image>
+			<filter>linear-mipmap-linear</filter>
+			<wrap-s>repeat</wrap-s>
+			<wrap-t>repeat</wrap-t>
+			<internal-format>normalized</internal-format>
+		</texture>
         <normalmap_dds type="float">0.0</normalmap_dds>
 		<saturation>
 			<use>/rendering/scene/saturation</use>
@@ -132,6 +139,9 @@
 		<fogtype>
 			<use>/sim/rendering/shaders/skydome</use>
 		</fogtype>
+		<ice_cover>
+			<use>/environment/sea/surface/ice-cover</use>
+		</ice_cover>
 		<!-- sea colors -->
 		<sea_r>
 			<use>/environment/sea/color_r</use>
@@ -312,6 +322,24 @@
 					<use>texture[6]/internal-format</use>
 				</internal-format>
 			</texture-unit>
+			<texture-unit>
+				<unit>7</unit>
+				<image>
+					<use>texture[10]/image</use>
+				</image>
+				<filter>
+					<use>texture[10]/filter</use>
+				</filter>
+				<wrap-s>
+					<use>texture[10]/wrap-s</use>
+				</wrap-s>
+				<wrap-t>
+					<use>texture[10]/wrap-t</use>
+				</wrap-t>
+				<internal-format>
+					<use>texture[10]/internal-format</use>
+				</internal-format>
+			</texture-unit>
 
 			<program>
 				<vertex-shader>Shaders/water_lightfield.vert</vertex-shader>
@@ -342,6 +370,11 @@
 				<type>sampler-2d</type>
 				<value type="int">6</value>
 			</uniform>
+			<uniform>
+				<name>ice_texture</name>
+				<type>sampler-2d</type>
+				<value type="int">7</value>
+			</uniform>
             <!-- normalmap is .dds-->
             <uniform>
                 <name>normalmap_dds</name>
@@ -486,6 +519,11 @@
         			<type>float</type>
         			<value><use>cloud_self_shading</use></value>
       			</uniform>
+			<uniform>
+        			<name>ice_cover</name>
+        			<type>float</type>
+        		<value><use>ice_cover</use></value>
+      		</uniform>
 			<!-- sea colors -->
 			<uniform>
 				<name>sea_r</name>
diff --git a/Environment/environment.xml b/Environment/environment.xml
index 43e8d8524..19290cfdd 100644
--- a/Environment/environment.xml
+++ b/Environment/environment.xml
@@ -404,6 +404,9 @@
     <color_r type="double" userarchive="n">0.148</color_r>
     <color_g type="double" userarchive="n">0.27</color_g>
     <color_b type="double" userarchive="n">0.3</color_b>
+   <surface>
+    <ice-cover> 0.0</ice-cover>
+   </surface>
   </sea>
 
   <!-- definitions for the scattering skydome shader -->
diff --git a/Shaders/water_lightfield.frag b/Shaders/water_lightfield.frag
index 58a78e6af..ce729cc5d 100644
--- a/Shaders/water_lightfield.frag
+++ b/Shaders/water_lightfield.frag
@@ -12,6 +12,7 @@ uniform sampler2D water_normalmap;
 uniform sampler2D water_dudvmap;
 uniform sampler2D sea_foam;
 uniform sampler2D perlin_normalmap;
+uniform sampler2D ice_texture;
 
 uniform sampler3D Noise;
 
@@ -23,8 +24,8 @@ varying vec4 waterTex2; //moving texcoords
 varying vec4 waterTex4; //viewts
 varying vec3 viewerdir;
 varying vec3 lightdir;
-//varying vec3 specular_light;
 varying vec3 relPos;
+varying vec3 rawPos;
 
 varying float earthShade;
 varying float yprime_alt;
@@ -49,6 +50,7 @@ uniform float scattering;
 uniform float ground_scattering;
 uniform float cloud_self_shading;
 uniform float eye_alt;
+uniform float ice_cover;
 uniform float sea_r;
 uniform float sea_g;
 uniform float sea_b;
@@ -68,6 +70,93 @@ vec3 fog_Func(vec3 color, int type);
 
 /////// functions /////////
 
+float rand2D(in vec2 co){
+    return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
+}
+
+float rand3D(in vec3 co){
+    return fract(sin(dot(co.xyz ,vec3(12.9898,78.233,144.7272))) * 43758.5453);
+}
+
+float cosine_interpolate(in float a, in float b, in float x)
+{
+	float ft = x * 3.1415927;
+	float f = (1.0 - cos(ft)) * .5;
+
+	return  a*(1.0-f) + b*f;
+}
+
+float simple_interpolate(in float a, in float b, in float x)
+{
+return a + smoothstep(0.0,1.0,x) * (b-a);
+}
+
+float interpolatedNoise2D(in float x, in float y)
+{
+      float integer_x    = x - fract(x);
+      float fractional_x = x - integer_x;
+
+      float integer_y    = y - fract(y);
+      float fractional_y = y - integer_y;
+
+      float v1 = rand2D(vec2(integer_x, integer_y));
+      float v2 = rand2D(vec2(integer_x+1.0, integer_y));
+      float v3 = rand2D(vec2(integer_x, integer_y+1.0));
+      float v4 = rand2D(vec2(integer_x+1.0, integer_y +1.0));
+
+      float i1 = simple_interpolate(v1 , v2 , fractional_x);
+      float i2 = simple_interpolate(v3 , v4 , fractional_x);
+
+      return simple_interpolate(i1 , i2 , fractional_y);
+}
+
+float interpolatedNoise3D(in float x, in float y, in float z)
+{
+      float integer_x    = x - fract(x);
+      float fractional_x = x - integer_x;
+
+      float integer_y    = y - fract(y);
+      float fractional_y = y - integer_y;
+
+      float integer_z    = z - fract(z);
+      float fractional_z = z - integer_z;
+
+      float v1 = rand3D(vec3(integer_x, integer_y, integer_z));
+      float v2 = rand3D(vec3(integer_x+1.0, integer_y, integer_z));
+      float v3 = rand3D(vec3(integer_x, integer_y+1.0, integer_z));
+      float v4 = rand3D(vec3(integer_x+1.0, integer_y +1.0, integer_z));
+
+      float v5 = rand3D(vec3(integer_x, integer_y, integer_z+1.0));
+      float v6 = rand3D(vec3(integer_x+1.0, integer_y, integer_z+1.0));
+      float v7 = rand3D(vec3(integer_x, integer_y+1.0, integer_z+1.0));
+      float v8 = rand3D(vec3(integer_x+1.0, integer_y +1.0, integer_z+1.0));
+
+
+      float i1 = simple_interpolate(v1,v5, fractional_z);
+      float i2 = simple_interpolate(v2,v6, fractional_z);
+      float i3 = simple_interpolate(v3,v7, fractional_z);
+      float i4 = simple_interpolate(v4,v8, fractional_z);
+
+      float ii1 = simple_interpolate(i1,i2,fractional_x);
+      float ii2 = simple_interpolate(i3,i4,fractional_x);
+ 
+
+      return simple_interpolate(ii1 , ii2 , fractional_y);
+}
+
+float Noise2D(in vec2 coord, in float wavelength)
+{
+return interpolatedNoise2D(coord.x/wavelength, coord.y/wavelength);
+
+}
+
+float Noise3D(in vec3 coord, in float wavelength)
+{
+return interpolatedNoise3D(coord.x/wavelength, coord.y/wavelength, coord.z/wavelength);
+}
+
+
+
 void rotationmatrix(in float angle, out mat4 rotmat)
 	{
 	rotmat = mat4( cos( angle ), -sin( angle ), 0.0, 0.0,
@@ -199,6 +288,12 @@ void main(void)
 	const vec4 sca2 = vec4(0.02, 0.02, 0.02, 0.02);
 	const vec4 tscale = vec4(0.25, 0.25, 0.25, 0.25);
 
+	float noise_50m = Noise3D(rawPos.xyz, 50.0);
+	float noise_250m = Noise3D(rawPos.xyz,250.0);
+	float noise_1500m = Noise3D(rawPos.xyz,1500.0);
+	float noise_2000m = Noise3D(rawPos.xyz,2000.0);
+	float noise_2500m = Noise3D(rawPos.xyz, 2500.0);
+
 	mat4 RotationMatrix;
 
 	// compute direction to viewer
@@ -332,6 +427,7 @@ void main(void)
    	if (normalmap_dds > 0)
         	{vNorm = -vNorm;}		//dds fix
 		
+	vNorm = vNorm * (0.5 + 0.5 * noise_250m);	
 
 	//load reflection
 	
@@ -342,6 +438,7 @@ void main(void)
 	refl.b = sea_b;
 	refl.a = 1.0; 
 	
+	refl.g = refl.g * (0.9 + 0.2* noise_2500m);
 
 	float intensity;
 	// de-saturate for reduced light
@@ -435,7 +532,16 @@ void main(void)
 		
 
 
-		finalColor *= ambient_light;
+	// add ice
+	vec4 ice_texel =  texture2D(ice_texture, vec2(waterTex2) * 0.2 );
+
+	float nSum =  0.5 * (noise_250m +  noise_50m);
+	float mix_factor = smoothstep(1.0 - ice_cover, 1.04-ice_cover, nSum);
+        finalColor  = mix(finalColor, ice_texel, mix_factor * ice_texel.a);
+	finalColor.a = 1.0;
+
+
+	finalColor *= ambient_light;
 
 
 
diff --git a/Shaders/water_lightfield.vert b/Shaders/water_lightfield.vert
index c6803a1dc..f3657a22b 100644
--- a/Shaders/water_lightfield.vert
+++ b/Shaders/water_lightfield.vert
@@ -11,7 +11,7 @@ varying vec4 waterTex1;
 varying vec4 waterTex2;
 varying vec4 waterTex4;
 varying vec3 relPos;
-
+varying vec3 rawPos;
 
 varying vec3 viewerdir;
 varying vec3 lightdir;
@@ -31,6 +31,7 @@ uniform float visibility;
 uniform float overcast;
 uniform float ground_scattering;
 
+uniform mat4 osg_ViewMatrixInverse;
 
 vec3 specular_light;
 
@@ -72,6 +73,7 @@ void main(void)
   
 
     vec3 shadedFogColor = vec3(0.65, 0.67, 0.78);
+    rawPos = (osg_ViewMatrixInverse *gl_ModelViewMatrix * gl_Vertex).xyz;
 
     vec4 ecPosition = gl_ModelViewMatrix * gl_Vertex;
 
diff --git a/gui/dialogs/environment-settings.xml b/gui/dialogs/environment-settings.xml
index e0c797315..a0481db81 100644
--- a/gui/dialogs/environment-settings.xml
+++ b/gui/dialogs/environment-settings.xml
@@ -194,13 +194,63 @@
       <col>3</col>
     </text>
 
+
+   <text>
+    <enable>
+     <property>/sim/rendering/shaders/skydome</property>
+     </enable>
+     <label>Ice cover</label>
+     <halign>left</halign>
+     <row>4</row>
+     <col>0</col>
+    </text>
+    
+    <text>
+     <enable>
+      <property>/sim/rendering/shaders/skydome</property> 
+     </enable>
+     <label>none</label>
+     <halign>right</halign>
+     <row>4</row>
+     <col>1</col>
+    </text>
+        
+    <slider>
+     <enable>
+      <property>/sim/rendering/shaders/skydome</property>
+     </enable>
+     <name>ice-cover</name>
+     <row>4</row>
+     <col>2</col>
+     <min>0.0</min>
+     <max>1.0</max>
+     <live>true</live>
+     <property>/environment/sea/surface/ice-cover</property>
+     <binding>
+       <command>dialog-apply</command>
+       <object-name>ice-cover</object-name>
+     </binding>
+    </slider>
+
+    <text>
+     <enable>
+      <property>/sim/rendering/shaders/skydome</property>
+     </enable>
+     <label>thick</label>
+     <halign>left</halign>
+     <row>4</row>
+     <col>3</col>
+    </text>
+
+
+
     <text>
       <enable>
        <property>/sim/rendering/shaders/skydome</property>
       </enable>
       <label>Dust cover</label>
       <halign>left</halign>
-      <row>4</row>
+      <row>5</row>
       <col>0</col>
     </text>
     
@@ -210,7 +260,7 @@
       </enable>
       <label>none</label>
       <halign>right</halign>
-      <row>4</row>
+      <row>5</row>
       <col>1</col>
     </text>
         
@@ -219,7 +269,7 @@
        <property>/sim/rendering/shaders/skydome</property>
       </enable>
       <name>dust-level</name>
-      <row>4</row>
+      <row>5</row>
       <col>2</col>
       <min>0.0</min>
       <max>0.7</max>
@@ -237,7 +287,7 @@
       </enable>
       <label>dusty</label>
       <halign>left</halign>
-      <row>4</row>
+      <row>5</row>
       <col>3</col>
     </text>
 
@@ -247,7 +297,7 @@
       </enable>
       <label>Wetness</label>
       <halign>left</halign>
-      <row>5</row>
+      <row>6</row>
       <col>0</col>
     </text>
     
@@ -257,7 +307,7 @@
       </enable>
       <label>dry</label>
       <halign>right</halign>
-      <row>5</row>
+      <row>6</row>
       <col>1</col>
     </text>
         
@@ -266,7 +316,7 @@
        <property>/sim/rendering/shaders/skydome</property>
       </enable>
       <name>wetness</name>
-      <row>5</row>
+      <row>6</row>
       <col>2</col>
       <min>0.0</min>
       <max>0.7</max>
@@ -284,7 +334,7 @@
       </enable>
       <label>wet</label>
       <halign>left</halign>
-      <row>5</row>
+      <row>6</row>
       <col>3</col>
     </text>
     
@@ -295,7 +345,7 @@
       </enable>
       <label>Vegetation</label>
       <halign>left</halign>
-      <row>6</row>
+      <row>7</row>
       <col>0</col>
     </text>
     
@@ -305,7 +355,7 @@
       </enable>
       <label>none</label>
       <halign>right</halign>
-      <row>6</row>
+      <row>7</row>
       <col>1</col>
     </text>
         
@@ -314,7 +364,7 @@
        <property>/sim/rendering/shaders/skydome</property>
       </enable>
       <name>lichen-level</name>
-      <row>6</row>
+      <row>7</row>
       <col>2</col>
       <min>0.0</min>
       <max>0.7</max>
@@ -332,7 +382,7 @@
       </enable>
       <label>mossy</label>
       <halign>left</halign>
-      <row>6</row>
+      <row>7</row>
       <col>3</col>
     </text>
 
@@ -343,7 +393,7 @@
       </enable>
       <label>Season (experimental)</label>
       <halign>left</halign>
-      <row>7</row>
+      <row>8</row>
       <col>0</col>
     </text>
     
@@ -353,7 +403,7 @@
       </enable>
       <label>summer</label>
       <halign>right</halign>
-      <row>7</row>
+      <row>8</row>
       <col>1</col>
     </text>
         
@@ -362,7 +412,7 @@
        <property>/sim/rendering/shaders/skydome</property>
       </enable>
       <name>season</name>
-      <row>7</row>
+      <row>8</row>
       <col>2</col>
       <min>0.0</min>
       <max>2.0</max>
@@ -380,7 +430,7 @@
       </enable>
       <label>late autumn</label>
       <halign>left</halign>
-      <row>7</row>
+      <row>8</row>
       <col>3</col>
     </text>