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fgdata/Compositor/Shaders/Default/bowwave.frag
2019-10-26 01:42:48 +02:00

217 lines
7 KiB
GLSL

// This shader is mostly an adaptation of the shader found at
// http://www.bonzaisoftware.com/water_tut.html and its glsl conversion
// available at http://forum.bonzaisoftware.com/viewthread.php?tid=10
// © Michael Horsch - 2005
// Major update and revisions - 2011-10-07
// © Emilian Huminiuc and Vivian Meazza
// Optimisation - 2012-5-05
// © Emilian Huminiuc and Vivian Meazza
#version 120
#define fps2kts 0.5925
uniform sampler2D water_normalmap;
uniform sampler2D water_reflection;
uniform sampler2D water_dudvmap;
uniform sampler2D water_reflection_grey;
uniform sampler2D sea_foam;
uniform sampler2D alpha_tex;
uniform sampler2D bowwave_nmap;
uniform float saturation, Overcast, WindE, WindN, spd, hdg;
uniform float CloudCover0, CloudCover1, CloudCover2, CloudCover3, CloudCover4;
uniform int Status;
varying vec4 waterTex1; //moving texcoords
varying vec4 waterTex2; //moving texcoords
varying vec3 viewerdir;
varying vec3 lightdir;
varying vec3 normal;
////fog "include" /////
uniform int fogType;
vec3 fog_Func(vec3 color, 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 the carrier 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(rel_wind_speed_from_east_kts*rel_wind_speed_from_east_kts
+ rel_wind_speed_from_north_kts*rel_wind_speed_from_north_kts);
//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(void)
{
const vec4 sca = vec4(0.005, 0.005, 0.005, 0.005);
const vec4 sca2 = vec4(0.02, 0.02, 0.02, 0.02);
const vec4 tscale = vec4(0.25, 0.25, 0.25, 0.25);
mat4 RotationMatrix;
float relWindspd=0;
float relWinddir=0;
// compute relative wind speed and direction
relWind (relWindspd, relWinddir);
rotationmatrix(relWinddir, RotationMatrix);
// compute direction to viewer
vec3 E = normalize(viewerdir);
// compute direction to light source
vec3 L = normalize(lightdir);
// half vector
vec3 H = normalize(L + E);
const float water_shininess = 240.0;
// approximate cloud cover
float cover = 0.0;
//bool Status = true;
float windEffect = relWindspd; //wind speed in kt
// float windEffect = sqrt(pow(abs(WindE),2)+pow(abs(WindN),2)) * 0.6; //wind speed in kt
float windScale = 15.0/(5.0 + windEffect); //wave scale
float waveRoughness = 0.05 + smoothstep(0.0, 50.0, windEffect); //wave roughness filter
if (Status == 1){
cover = min(min(min(min(CloudCover0, CloudCover1),CloudCover2),CloudCover3),CloudCover4);
} else {
// hack to allow for Overcast not to be set by Local Weather
if (Overcast == 0){
cover = 5;
} else {
cover = Overcast * 5;
}
}
//vec4 viewt = normalize(waterTex4);
vec4 viewt = vec4(-E, 0.0) * 0.6;
vec4 disdis = texture2D(water_dudvmap, vec2(waterTex2 * tscale)* windScale * 2.0) * 2.0 - 1.0;
vec4 dist = texture2D(water_dudvmap, vec2(waterTex1 + disdis*sca2)* windScale * 2.0) * 2.0 - 1.0;
vec4 fdist = normalize(dist);
fdist = -fdist;
fdist *= sca;
//normalmap
rotationmatrix(-relWinddir, RotationMatrix);
vec4 nmap0 = texture2D(water_normalmap, vec2((waterTex1 + disdis*sca2) * RotationMatrix ) * windScale * 2.0) * 2.0 - 1.0;
vec4 nmap2 = texture2D(water_normalmap, vec2(waterTex2 * tscale * RotationMatrix ) * windScale * 2.0) * 2.0 - 1.0;
vec4 nmap3 = texture2D(bowwave_nmap, gl_TexCoord[0].st) * 2.0 - 1.0;
vec4 vNorm = normalize(mix(nmap3, nmap0 + nmap2, 0.3 )* waveRoughness);
vNorm = -vNorm;
//load reflection
vec4 tmp = vec4(lightdir, 0.0);
vec4 refTex = texture2D(water_reflection, vec2(tmp + waterTex1) * 32.0) ;
vec4 refTexGrey = texture2D(water_reflection_grey, vec2(tmp + waterTex1) * 32.0) ;
vec4 refl ;
// cover = 0;
if(cover >= 1.5){
refl= normalize(refTex);
}
else
{
refl = normalize(refTexGrey);
refl.r *= (0.75 + 0.15 * cover);
refl.g *= (0.80 + 0.15 * cover);
refl.b *= (0.875 + 0.125 * cover);
refl.a *= 1.0;
}
vec3 N0 = vec3(texture2D(water_normalmap, vec2((waterTex1 + disdis*sca2)* RotationMatrix) * windScale * 2.0) * 2.0 - 1.0);
vec3 N1 = vec3(texture2D(water_normalmap, vec2(waterTex2 * tscale * RotationMatrix ) * windScale * 2.0) * 2.0 - 1.0);
vec3 N2 = vec3(texture2D(bowwave_nmap, gl_TexCoord[0].st)*2.0-1.0);
//vec3 Nf = normalize((normal+N0+N1)*waveRoughness);
vec3 N = normalize(mix(normal+N2, normal+N0+N1, 0.3)* waveRoughness);
N = -N;
// specular
vec3 specular_color = vec3(gl_LightSource[0].diffuse)
* pow(max(0.0, dot(N, H)), water_shininess) * 6.0;
vec4 specular = vec4(specular_color, 0.5);
specular = specular * saturation * 0.3;
//calculate fresnel
vec4 invfres = vec4( dot(vNorm, viewt) );
vec4 fres = vec4(1.0) + invfres;
refl *= fres;
vec4 alpha0 = texture2D(alpha_tex, gl_TexCoord[0].st);
//calculate final colour
vec4 ambient_light = gl_LightSource[0].diffuse;
vec4 finalColor;
// cover = 0;
if(cover >= 1.5){
finalColor = refl + specular;
} else {
finalColor = refl;
}
//add foam
float foamSlope = 0.05 + 0.01 * windScale;
//float waveSlope = mix(N0.g, N1.g, 0.25);
vec4 foam_texel = texture2D(sea_foam, vec2(waterTex2 * tscale) * 50.0);
float waveSlope = N.g;
if (windEffect >= 12.0)
if (waveSlope >= foamSlope){
finalColor = mix(finalColor, max(finalColor, finalColor + foam_texel), smoothstep(foamSlope, 0.5, N.g));
}
//generate final colour
finalColor *= ambient_light+ alpha0 * 0.35;
finalColor.rgb = fog_Func(finalColor.rgb, fogType);
gl_FragColor = vec4(finalColor.rgb, alpha0.a * 1.35);
}