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fgdata/Shaders/water_sine.frag
Vivian Meazza 9657518663 Optimise water shaders after ideas and suggestions by Thorsten Renk
Signed-off-by: Vivian Meazza <vivian.meazza@lineone.net>
2012-05-05 19:59:22 +01:00

380 lines
11 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
// Based on ideas by Thorsten Renk
// © Emilian Huminiuc and Vivian Meazza
#version 120
uniform sampler2D water_normalmap;
uniform sampler2D water_reflection;
uniform sampler2D water_dudvmap;
uniform sampler2D water_reflection_grey;
uniform sampler2D sea_foam;
uniform sampler2D perlin_normalmap;
uniform sampler3D Noise;
uniform float saturation, Overcast, WindE, WindN;
uniform float CloudCover0, CloudCover1, CloudCover2, CloudCover3, CloudCover4;
uniform float osg_SimulationTime;
uniform int Status;
varying vec4 waterTex1; //moving texcoords
varying vec4 waterTex2; //moving texcoords
varying vec3 viewerdir;
varying vec3 lightdir;
varying vec3 normal;
uniform float WaveFreq ;
uniform float WaveAmp ;
uniform float WaveSharp ;
uniform float WaveAngle ;
uniform float WaveFactor ;
uniform float WaveDAngle ;
////fog "include" /////
uniform int fogType;
vec3 fog_Func(vec3 color, int type);
//////////////////////
const vec4 AllOnes = vec4(1.0);
/////// functions /////////
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 );
}
// wave functions ///////////////////////
struct Wave {
float freq; // 2*PI / wavelength
float amp; // amplitude
float phase; // speed * 2*PI / wavelength
vec2 dir;
};
Wave wave0 = Wave(1.0, 1.0, 0.5, vec2(0.97, 0.25));
Wave wave1 = Wave(2.0, 0.5, 1.3, vec2(0.97, -0.25));
Wave wave2 = Wave(1.0, 1.0, 0.6, vec2(0.95, -0.3));
Wave wave3 = Wave(2.0, 0.5, 1.4, vec2(0.99, 0.1));
float evaluateWave(in Wave w, vec2 pos, float t)
{
return w.amp * sin( dot(w.dir, pos) * w.freq + t * w.phase);
}
// derivative of wave function
float evaluateWaveDeriv(Wave w, vec2 pos, float t)
{
return w.freq * w.amp * cos( dot(w.dir, pos)*w.freq + t*w.phase);
}
// sharp wave functions
float evaluateWaveSharp(Wave w, vec2 pos, float t, float k)
{
return w.amp * pow(sin( dot(w.dir, pos)*w.freq + t*w.phase)* 0.5 + 0.5 , k);
}
float evaluateWaveDerivSharp(Wave w, vec2 pos, float t, float k)
{
return k*w.freq*w.amp * pow(sin( dot(w.dir, pos)*w.freq + t*w.phase)* 0.5 + 0.5 , k - 1) * cos( dot(w.dir, pos)*w.freq + t*w.phase);
}
void sumWaves(float angle, float dangle, float windScale, float factor, out float ddx, float ddy)
{
mat4 RotationMatrix;
float deriv;
vec4 P = waterTex1 * 1024.0;
rotationmatrix(radians(angle + dangle * windScale + 0.6 * sin(P.x * factor)), RotationMatrix);
P *= RotationMatrix;
P.y += evaluateWave(wave0, P.xz, osg_SimulationTime);
deriv = evaluateWaveDeriv(wave0, P.xz, osg_SimulationTime );
ddx = deriv * wave0.dir.x;
ddy = deriv * wave0.dir.y;
P.y += evaluateWave(wave1, P.xz, osg_SimulationTime);
deriv = evaluateWaveDeriv(wave1, P.xz, osg_SimulationTime);
ddx += deriv * wave1.dir.x;
ddy += deriv * wave1.dir.y;
P.y += evaluateWaveSharp(wave2, P.xz, osg_SimulationTime, WaveSharp);
deriv = evaluateWaveDerivSharp(wave2, P.xz, osg_SimulationTime, WaveSharp);
ddx += deriv * wave2.dir.x;
ddy += deriv * wave2.dir.y;
P.y += evaluateWaveSharp(wave3, P.xz, osg_SimulationTime, WaveSharp);
deriv = evaluateWaveDerivSharp(wave3, P.xz, osg_SimulationTime, WaveSharp);
ddx += deriv * wave3.dir.x;
ddy += deriv * wave3.dir.y;
}
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;
// compute direction to viewer
vec3 E = normalize(viewerdir);
// compute direction to light source
vec3 L = normalize(lightdir);
// half vector
vec3 H = normalize(L + E);
vec3 Normal = normalize(normal);
const float water_shininess = 240.0;
float range = gl_ProjectionMatrix[3].z/(gl_FragCoord.z * -2.0 + 1.0 - gl_ProjectionMatrix[2].z);
// approximate cloud cover
float cover = 0.0;
//bool Status = true;
float windEffect = sqrt( WindE*WindE + WindN*WindN ) * 0.6; //wind speed in kt
float windScale = 15.0/(3.0 + windEffect); //wave scale
float windEffect_low = 0.3 + 0.7 * smoothstep(0.0, 5.0, windEffect); //low windspeed wave filter
float waveRoughness = 0.01 + smoothstep(0.0, 40.0, windEffect); //wave roughness filter
float mixFactor = 0.2 + 0.02 * smoothstep(0.0, 50.0, windEffect);
//mixFactor = 0.2;
mixFactor = clamp(mixFactor, 0.3, 0.8);
// sine waves
// Test data
//float WaveFreq =1.0;
//float WaveAmp = 1000.0;
//float WaveSharp = 10.0;
vec4 ddxVec = vec4(0.0);
vec4 ddyVec = vec4(0.0);
int detailFlag = 0;
//uncomment to test
//range = -20000;
if (range > -15000 || dot(Normal,H) > 0.95 ) {
float ddx = 0.0, ddy = 0.0;
float ddx1 = 0.0, ddy1 = 0.0;
float ddx2 = 0.0, ddy2 = 0.0;
float ddx3 = 0.0, ddy3 = 0.0;
float waveamp;
float angle = 0.0;
wave0.freq = WaveFreq ;
wave0.amp = WaveAmp;
wave0.dir = vec2(cos(radians(angle)), sin(radians(angle)));
angle -= 45;
wave1.freq = WaveFreq * 2.0 ;
wave1.amp = WaveAmp * 1.25;
wave1.dir = vec2(cos(radians(angle)), sin(radians(angle)));
angle += 30;
wave2.freq = WaveFreq * 3.5;
wave2.amp = WaveAmp * 0.75;
wave2.dir = vec2(cos(radians(angle)), sin(radians(angle)));
angle -= 50;
wave3.freq = WaveFreq * 3.0 ;
wave3.amp = WaveAmp * 0.75;
wave3.dir = vec2(cos(radians(angle)), sin(radians(angle)));
// sum waves
ddx = 0.0, ddy = 0.0;
sumWaves(WaveAngle, -1.5, windScale, WaveFactor, ddx, ddy);
ddx1 = 0.0, ddy1 = 0.0;
sumWaves(WaveAngle, 1.5, windScale, WaveFactor, ddx1, ddy1);
//reset the waves
angle = 0.0;
waveamp = WaveAmp * 0.75;
wave0.freq = WaveFreq ;
wave0.amp = waveamp;
wave0.dir = vec2(cos(radians(angle)), sin(radians(angle)));
angle -= 20;
wave1.freq = WaveFreq * 2.0 ;
wave1.amp = waveamp * 1.25;
wave1.dir = vec2(cos(radians(angle)), sin(radians(angle)));
angle += 35;
wave2.freq = WaveFreq * 3.5;
wave2.amp = waveamp * 0.75;
wave2.dir = vec2(cos(radians(angle)), sin(radians(angle)));
angle -= 45;
wave3.freq = WaveFreq * 3.0 ;
wave3.amp = waveamp * 0.75;
wave3.dir = vec2(cos(radians(angle)), sin(radians(angle)));
// sum waves
ddx2 = 0.0, ddy2 = 0.0;
sumWaves(WaveAngle + WaveDAngle, -1.5, windScale, WaveFactor, ddx2, ddy2);
ddx3 = 0.0, ddy3 = 0.0;
sumWaves(WaveAngle + WaveDAngle, 1.5, windScale, WaveFactor, ddx3, ddy3);
ddxVec = vec4(ddx, ddx1, ddx2, ddx3);
ddyVec = vec4(ddy, ddy1, ddy2, ddy3);
//toggle detailFlag
detailFlag = 1;
} // end sine stuff
float ddxSum = dot(ddxVec, AllOnes);
float ddySum = dot(ddyVec, AllOnes);
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 - 1.0;
//normalmaps
vec4 nmap = texture2D(water_normalmap, vec2(waterTex1 + disdis * sca2) * windScale) * 2.0 - 1.0;
vec4 nmap1 = texture2D(perlin_normalmap, vec2(waterTex1 + disdis * sca2) * windScale) * 2.0 - 1.0;
rotationmatrix(radians(3.0 * sin(osg_SimulationTime * 0.0075)), RotationMatrix);
nmap += texture2D(water_normalmap, vec2(waterTex2 * RotationMatrix * tscale) * windScale) * 2.0 - 1.0;
nmap1 += texture2D(perlin_normalmap, vec2(waterTex2 * RotationMatrix * tscale) * windScale) * 2.0 - 1.0;
nmap *= windEffect_low;
nmap1 *= windEffect_low;
// mix water and noise, modulated by factor
vec4 vNorm = normalize(mix(nmap, nmap1, mixFactor) * waveRoughness);
vNorm.r += ddxSum;
vNorm = -vNorm; //dds fix
//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)) ;
vec4 refl ;
// Test data
// cover = 0;
if(cover >= 1.5){
refl = normalize(refTex);
refl.a = 1.0;
}
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) * windScale) * 2.0 - 1.0);
vec3 N1 = vec3(texture2D(perlin_normalmap, vec2(waterTex1 + disdis * sca) * windScale) * 2.0 - 1.0);
N0 += vec3(texture2D(water_normalmap, vec2(waterTex1 * tscale) * windScale) * 2.0 - 1.0);
N1 += vec3(texture2D(perlin_normalmap, vec2(waterTex2 * tscale) * windScale) * 2.0 - 1.0);
rotationmatrix(radians(2.0 * sin(osg_SimulationTime * 0.005)), RotationMatrix);
N0 += vec3(texture2D(water_normalmap, vec2(waterTex2 * RotationMatrix * (tscale + sca2)) * windScale) * 2.0 - 1.0);
N1 += vec3(texture2D(perlin_normalmap, vec2(waterTex2 * RotationMatrix * (tscale + sca2)) * windScale) * 2.0 - 1.0);
rotationmatrix(radians(-4.0 * sin(osg_SimulationTime * 0.003)), RotationMatrix);
N0 += vec3(texture2D(water_normalmap, vec2(waterTex1 * RotationMatrix + disdis * sca2) * windScale) * 2.0 - 1.0);
N1 += vec3(texture2D(perlin_normalmap, vec2(waterTex1 * RotationMatrix + disdis * sca) * windScale) * 2.0 - 1.0);
if(detailFlag > 0)
{
N0 *= windEffect_low;
N1 *= windEffect_low;
//N0.r += (ddx + ddx1 + ddx2 + ddx3);
//N0.g += (ddy + ddy1 + ddy2 + ddy3);
N0.r += ddxSum;
N0.g += ddySum;
Normal = normalize(mix(Normal + N0, Normal + N1, mixFactor) * waveRoughness);
Normal = -Normal; //dds fix
}
// specular
vec3 specular_color = vec3(gl_LightSource[0].diffuse)
* pow(max(0.0, dot(Normal, 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;
//calculate final colour
vec4 ambient_light = gl_LightSource[0].diffuse;
vec4 finalColor;
if(cover >= 1.5){
finalColor = refl + specular;
} else {
finalColor = refl;
}
//add foam
vec4 foam_texel = texture2D(sea_foam, vec2(waterTex2 * tscale) * 25.0);
if (range > -10000.0){
float foamSlope = 0.1 + 0.1 * windScale;
//float waveSlope = mix(N0.g, N1.g, 0.25);
float waveSlope = Normal.g;
if (windEffect >= 8.0)
if (waveSlope >= foamSlope){
finalColor = mix(finalColor, max(finalColor, finalColor + foam_texel),
smoothstep(0.01, 0.50, Normal.g));
}
} // end range
finalColor *= ambient_light;
//gl_FragColor = mix(gl_Fog.color, finalColor, fogFactor);
finalColor.rgb = fog_Func(finalColor.rgb, fogType);
gl_FragColor = finalColor;
}