Standardize fog

Signed-off-by: Vivian Meazza <vivian.meazza@lineone.net>

Shaders/default.frag

@@ -1,12 +1,19 @@
 // -*-C++-*-
 
 // Ambient term comes in gl_Color.rgb.
+#version 120
+
 varying vec4 diffuse_term;
 varying vec3 normal;
-varying float fogCoord;
 
 uniform sampler2D texture;
 
+////fog "include" /////
+uniform int fogType;
+
+vec3 fog_Func(vec3 color, int type);
+//////////////////////
+
 float luminance(vec3 color)
 {
     return dot(vec3(0.212671, 0.715160, 0.072169), color);
@@ -44,6 +51,7 @@ void main()
     color = clamp(color, 0.0, 1.0);
     texel = texture2D(texture, gl_TexCoord[0].st);
     fragColor = color * texel + specular;
-    fogFactor = exp(-gl_Fog.density * gl_Fog.density * fogCoord * fogCoord);
-    gl_FragColor = mix(gl_Fog.color, fragColor, fogFactor);
+
+    fragColor.rgb = fog_Func(fragColor.rgb, fogType);
+    gl_FragColor = fragColor;
 }

Shaders/default.vert

@@ -7,7 +7,7 @@
 //
 // Diffuse colors come from the gl_Color, ambient from the material. This is
 // equivalent to osg::Material::DIFFUSE.
-
+#version 120
 #define MODE_OFF 0
 #define MODE_DIFFUSE 1
 #define MODE_AMBIENT_AND_DIFFUSE 2
@@ -18,12 +18,17 @@
 // bugs with gl_FrontFacing in the fragment shader.
 varying vec4 diffuse_term;
 varying vec3 normal;
-varying float fogCoord;
+
 uniform int colorMode;
 
+////fog "include"////////
+uniform int fogType;
+
+void fog_Func(int type);
+/////////////////////////
+
 void main()
 {
-    vec4 ecPosition = gl_ModelViewMatrix * gl_Vertex;
     gl_Position = ftransform();
     gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
     normal = gl_NormalMatrix * gl_Normal;
@@ -51,5 +56,6 @@ void main()
     // gl_FrontFacing in the fragment shader.
     gl_FrontColor.rgb = constant_term.rgb;  gl_FrontColor.a = 1.0;
     gl_BackColor.rgb = constant_term.rgb; gl_BackColor.a = 0.0;
-    fogCoord = abs(ecPosition.z / ecPosition.w);
+    //fogCoord = abs(ecPosition.z / ecPosition.w);
+		fog_Func(fogType);
 }

Shaders/flutter.vert

@@ -1,4 +1,5 @@
 // -*-C++-*-
+//  © Vivian Meazza - 2011
 
 // Shader that uses OpenGL state values to do per-pixel lighting
 //
@@ -8,6 +9,9 @@
 // Diffuse colors come from the gl_Color, ambient from the material. This is
 // equivalent to osg::Material::DIFFUSE.
 
+#version 120
+#define fps2kts 0.5925
+
 #define MODE_OFF 0
 #define MODE_DIFFUSE 1
 #define MODE_AMBIENT_AND_DIFFUSE 2
@@ -18,15 +22,69 @@
 // bugs with gl_FrontFacing in the fragment shader.
 varying vec4 diffuse_term;
 varying vec3 normal;
-varying float fogCoord;
+//varying float fogCoord;
 
 uniform int colorMode;
 uniform float osg_SimulationTime;
-uniform float WindSpeed, Offset, AmpFactor;
+uniform float Offset, AmpFactor, WindE, WindN, spd, hdg;
 uniform sampler3D Noise;
 
+////fog "include"////////
+uniform int fogType;
+
+void fog_Func(int type);
+/////////////////////////
+
+/////// functions /////////
+
+float normalize_range(float _val)
+    {
+    if (_val > 180.0)
+        return _val - 360.0;
+    else
+        return _val;
+    }
+
+void relWind(out float rel_wind_speed_kts, out float rel_wind_from_rad)
+    {
+    //calculate speed north and east in kts
+    float speed_north_kts = cos(radians(hdg)) * spd ;
+    float speed_east_kts  = sin(radians(hdg)) * spd ;
+
+    //calculate the relative wind speed north and east in kts
+    float rel_wind_speed_from_east_kts = WindE*fps2kts + speed_east_kts;
+    float rel_wind_speed_from_north_kts = WindN*fps2kts + speed_north_kts;
+
+    //combine relative speeds north and east to get relative windspeed in kts
+    rel_wind_speed_kts = sqrt(pow(abs(rel_wind_speed_from_east_kts), 2) 
+        + pow(abs(rel_wind_speed_from_north_kts), 2));
+
+    //calculate the relative wind direction
+    float rel_wind_from_deg = degrees(atan(rel_wind_speed_from_east_kts, rel_wind_speed_from_north_kts));
+    //rel_wind_from_rad = atan(rel_wind_speed_from_east_kts, rel_wind_speed_from_north_kts);
+    float rel_wind = rel_wind_from_deg - hdg;
+    rel_wind = normalize_range(rel_wind);
+    rel_wind_from_rad = radians(rel_wind);
+    }
+
+void rotationmatrix(in float angle, out mat4 rotmat)
+    {
+    rotmat = mat4( cos( angle ), -sin( angle ), 0.0, 0.0,
+        sin( angle ),  cos( angle ), 0.0, 0.0,
+        0.0         ,  0.0         , 1.0, 0.0,
+        0.0         ,  0.0         , 0.0, 1.0 );
+    }
+
 void main()
     {
+    mat4 RotationMatrix;
+
+    float relWindspd=0;
+    float relWinddir=0;
+
+    // compute relative wind speed and direction
+    relWind (relWindspd, relWinddir);
+
     // map noise vector
     vec4 noisevec = texture3D(Noise, gl_Vertex.xyz);
 
@@ -35,14 +93,18 @@ void main()
     vec4 pos = gl_Vertex;
     vec4 oldpos = gl_Vertex;
 
-    float freq = (10 * WindSpeed) + 10;
+    float freq = (10 * relWindspd) + 10;
     pos.y = sin((pos.x * 5.0 + tsec * freq )/5.0) * 0.5 ;
     pos.y += sin((pos.z * 5.0 + tsec * freq/2)/5.0) * 0.125 ;
 
     pos.y *= pow(pos.x - Offset, 2.0) * AmpFactor;
 
+    //rotate the flag to align with relative wind
+    rotationmatrix(-relWinddir, RotationMatrix);
+    pos *= RotationMatrix;
     gl_Position = gl_ModelViewProjectionMatrix * pos;
 
+    //do the colour and fog
     vec4 ecPosition = gl_ModelViewMatrix * gl_Vertex;
 
     gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
@@ -74,6 +136,8 @@ void main()
         // gl_FrontFacing in the fragment shader.
         gl_FrontColor.rgb = ambient_term.rgb;  gl_FrontColor.a = 0.0;
         gl_BackColor.rgb = ambient_term.rgb; gl_FrontColor.a = 1.0;
-    fogCoord = abs(ecPosition.z / ecPosition.w);
+//        fogCoord = abs(ecPosition.z / ecPosition.w);
+
+        fog_Func(fogType);
 
     }

Shaders/landmass-g.vert

@@ -31,6 +31,12 @@ attribute vec3 binormal;
 
 uniform float canopy_height;
 
+////fog "include"////////
+uniform int fogType;
+
+void fog_Func(int type);
+/////////////////////////
+
 void main(void)
     {
     rawposIn = gl_Vertex;
@@ -48,4 +54,6 @@ void main(void)
     gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
     constantColorIn = gl_FrontMaterial.emission
         + gl_Color * (gl_LightModel.ambient + gl_LightSource[0].ambient);
+
+    fog_Func(fogType);
     }

Shaders/terrain-nocolor.frag

@@ -1,15 +1,26 @@
 // -*-C++-*-
 uniform sampler2D texture;
 
+////fog "include" /////
+uniform int fogType;
+
+vec3 fog_Func(vec3 color, int type);
+//////////////////////
+
+
 void main()
 {
     vec4 color = vec4(1.0, 1.0, 1.0, 1.0);
     vec4 texel;
     vec4 fragColor;
+    vec4 finalColor;
 
     texel = texture2D(texture, gl_TexCoord[0].st);
     fragColor = color * texel;
 
     gl_FragColor = fragColor;
 
+    finalColor.rgb = fog_Func(fragColor.rgb, fogType);
+    gl_FragColor = finalColor;
+
 }