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fgdata/Shaders/ws30-ALS-detailed.frag
Stuart Buchanan 98fda02e65 WS30: Combined land and water shader
Previously the water shader was separate and executed on a
different mesh.

This adds the water shader as a separate fragment function
(ws30-water.frag) and uses a material parameter passed in
as a Uniform to use it in preference to the usual texel
lookup.

Performance testing found a slight performance improvement
from having a single mesh, but a slight performance impact
from the extra fragment shader complexity.
2022-02-05 15:24:02 +00:00

597 lines
20 KiB
C++

// WS30 FRAGMENT SHADER
// -*-C++-*-
#version 130
#extension GL_EXT_texture_array : enable
// written by Thorsten Renk, Oct 2011, based on default.frag
//////////////////////////////////////////////////////////////////
// TEST PHASE TOGGLES AND CONTROLS
//
// Development tools:
// Reduce haze to almost zero, while preserving lighting. Useful for observing distant tiles.
// Keeps the calculation overhead. This can be used for profiling.
// Possible values: 0:Normal, 1:Reduced haze.
const int reduce_haze_without_removing_calculation_overhead = 0;
// Remove haze and lighting and shows just the texture.
// Useful for checking texture rendering and scenery.
// The compiler will likely optimise out the haze and lighting calculations.
// Possible values: 0:Normal, 1:Just the texture.
const int remove_haze_and_lighting = 0;
// Use built-in water shader. Use for testing impact of ws30-water.frag
const int water_shader = 1;
//
// End of test phase controls
//////////////////////////////////////////////////////////////////
// written by Thorsten Renk, Oct 2011, based on default.frag
// Ambient term comes in gl_Color.rgb.
varying vec4 light_diffuse_comp;
varying vec3 normal;
varying vec3 relPos;
varying vec2 ground_tex_coord;
varying vec2 rawPos;
varying vec3 worldPos;
// Testing code:
//vec3 worldPos = vec3(5000.0, 6000.0, 7000.0) + vec3(vec2(rawPos), 600.0); // vec3(100.0, 10.0, 3.0);
//varying vec2 orthoTexCoord;
varying vec4 eyePos;
uniform sampler2D landclass;
uniform sampler2DArray textureArray;
uniform sampler2D perlin;
//varying float yprime_alt;
//varying float mie_angle;
varying float steepness;
uniform float visibility;
uniform float avisibility;
uniform float scattering;
uniform float terminator;
uniform float terrain_alt;
uniform float hazeLayerAltitude;
uniform float overcast;
uniform float eye_alt;
uniform float snowlevel;
uniform float dust_cover_factor;
uniform float lichen_cover_factor;
uniform float wetness;
uniform float fogstructure;
uniform float snow_thickness_factor;
uniform float cloud_self_shading;
uniform float season;
uniform int quality_level;
uniform int tquality_level;
// Passed from VPBTechnique, not the Effect
uniform float fg_tileWidth;
uniform float fg_tileHeight;
uniform bool fg_photoScenery;
uniform vec4 fg_dimensionsArray[128];
uniform vec4 fg_ambientArray[128];
uniform vec4 fg_diffuseArray[128];
uniform vec4 fg_specularArray[128];
uniform vec4 fg_textureLookup1[128];
uniform vec4 fg_textureLookup2[128];
uniform vec4 fg_materialParams1[128];
uniform vec4 fg_materialParams3[128];
uniform mat4 fg_zUpTransform;
uniform vec3 fg_modelOffset;
const float EarthRadius = 5800000.0;
const float terminator_width = 200000.0;
//Testing phase: Why are these in global scope in WS2 shaders?
float alt;
float eShade;
float yprime_alt;
float mie_angle;
float shadow_func (in float x, in float y, in float noise, in float dist);
float DotNoise2D(in vec2 coord, in float wavelength, in float fractionalMaxDotSize, in float dot_density);
float Noise2D(in vec2 coord, in float wavelength);
float Noise3D(in vec3 coord, in float wavelength);
float SlopeLines2D(in vec2 coord, in vec2 gradDir, in float wavelength, in float steepness);
float Strata3D(in vec3 coord, in float wavelength, in float variation);
float fog_func (in float targ, in float alt);
float rayleigh_in_func(in float dist, in float air_pollution, in float avisibility, in float eye_alt, in float vertex_alt);
float alt_factor(in float eye_alt, in float vertex_alt);
float light_distance_fading(in float dist);
float fog_backscatter(in float avisibility);
vec3 rayleigh_out_shift(in vec3 color, in float outscatter);
vec3 get_hazeColor(in float light_arg);
vec3 searchlight();
vec3 landing_light(in float offset, in float offsetv);
vec3 filter_combined (in vec3 color) ;
float getShadowing();
vec3 getClusteredLightsContribution(vec3 p, vec3 n, vec3 texel);
//////////////////////////
// Test-phase code:
// These should be sent as uniforms
// Tile dimensions in meters
// vec2 tile_size = vec2(tile_width , tile_height);
// Testing: texture coords are sent flipped right now:
// Note tile_size is defined in the shader include: ws30-landclass-search-functions.frag.
// vec2 tile_size = vec2(tile_height , tile_width);
// From noise.frag
float rand2D(in vec2 co);
// Create random landclasses without a texture lookup to stress test.
// Each square of square_size in m is assigned a random landclass value.
int get_random_landclass(in vec2 co, in vec2 tile_size);
// End Test-phase code
////////////////////////
// These functions, and other function they depend on, are defined
// in ws30-ALS-landclass-search.frag.
// Lookup a ground texture at a point based on the landclass at that point, without visible
// seams at coordinate discontinuities or at landclass boundaries where texture are switched.
// The partial derivatives of the tile_coord at the fragment is needed to adjust for
// the stretching of different textures, so that the correct mip-map level is looked
// up and there are no seams.
// Texture types: 0: base texture, 1: grain texture, 2: gradient texture, 3 dot texture,
// 4: mix texture, 5: detail texture.
vec4 lookup_ground_texture_array(in int texture_type, in vec2 ground_texture_coord, in int landclass_id,
in vec4 dFdx_and_dFdy);
// Look up the landclass id [0 .. 255] for this particular fragment.
// Lookup id of any neighbouring landclass that is within the search distance.
// Searches are performed in upto 4 directions right now, but only one landclass is looked up
// Create a mix factor weighting the influences of nearby landclasses
void get_landclass_id(in vec2 tile_coord, in vec4 dFdx_and_dFdy,
out int landclass_id, out ivec4 neighbor_landclass_ids,
out int num_unique_neighbors,out vec4 mix_factor
);
// Look up the texel of the specified texture type (e.g. grain or detail textures) for this fragment
// and any neighbor texels, then mix.
vec4 get_mixed_texel(in int texture_type, in vec2 g_texture_coord,
in int landclass_id, in int num_unique_neighbors,
in ivec4 neighbor_texel_landclass_ids, in vec4 neighbor_mix_factors,
in vec4 dFdx_and_dFdy
);
// Determine the texel and material parameters for a particular fragment,
// Taking into account photoscenery etc.
void get_material(in int landclass,
in vec2 ground_tex_coord,
in vec4 dxdy_gc,
out float mat_shininess,
out vec4 mat_ambient,
out vec4 mat_diffuse,
out vec4 mat_specular,
out vec4 dxdy,
out vec2 st
);
// Apply the ALS haze model to a specific fragment
vec4 applyHaze(inout vec4 fragColor,
inout vec3 hazeColor,
in vec3 secondary_light,
in float ct,
in float hazeLayerAltitude,
in float visibility,
in float avisibility,
in float dist,
in float lightArg,
in float mie_angle);
// Procedurally generate a water texel for this fragment
vec4 generateWaterTexel();
void main()
{
yprime_alt = light_diffuse_comp.a;
//diffuse_term.a = 1.0;
mie_angle = gl_Color.a;
float effective_scattering = min(scattering, cloud_self_shading);
// distance to fragment
float dist = length(relPos);
// angle of view vector with horizon
float ct = dot(vec3(0.0, 0.0, 1.0), relPos)/dist;
// Altitude of fragment above sea level
float msl_altitude = (relPos.z + eye_alt);
vec3 shadedFogColor = vec3(0.55, 0.67, 0.88);
// this is taken from default.frag
vec3 n;
float NdotL, NdotHV, fogFactor;
vec3 lightDir = gl_LightSource[0].position.xyz;
vec3 halfVector = gl_LightSource[0].halfVector.xyz;
//vec3 halfVector = normalize(normalize(lightDir) + normalize(ecViewdir));
vec4 texel;
vec4 snow_texel;
vec4 detail_texel;
vec4 mix_texel;
vec4 fragColor;
vec4 specular = vec4(0.0);
float intensity;
// Material/texel properties
float mat_shininess;
vec2 st;
vec4 mat_ambient, mat_diffuse, mat_specular, dxdy;
// get noise at different wavelengths
// used: 5m, 5m gradient, 10m, 10m gradient: heightmap of the closeup terrain, 10m also snow
// 50m: detail texel
// 250m: detail texel
// 500m: distortion and overlay
// 1500m: overlay, detail, dust, fog
// 2000m: overlay, detail, snow, fog
float noise_10m;
float noise_5m;
noise_10m = Noise2D(rawPos.xy, 10.0);
noise_5m = Noise2D(rawPos.xy ,5.0);
float noisegrad_10m;
float noisegrad_5m;
float noise_50m = Noise2D(rawPos.xy, 50.0);;
float noise_250m = Noise3D(worldPos.xyz,250.0);
float noise_500m = Noise3D(worldPos.xyz, 500.0);
float noise_1500m = Noise3D(worldPos.xyz, 1500.0);
float noise_2000m = Noise3D(worldPos.xyz, 2000.0);
//
// get the texels
// Oct 27 2021:
// Geometry is in the form of roughly rectangular 'tiles'
// with a mesh forming a grid with regular spacing.
// Each vertex in the mesh is given an elevation
// Tile dimensions in m
// Testing: created from two float uniforms in global scope. Should be sent as a vec2
// vec2 tile_size
// Tile texture coordinates range [0..1] over the tile 'rectangle'
vec2 tile_coord = gl_TexCoord[0].st;
// Test phase: Constants and toggles for transitions between landlcasses are defined at
// the top of this file.
// Look up the landclass id [0 .. 255] for this particular fragment
// and any neighbouring landclass that is close.
// Each tile has 1 texture containing landclass ids stetched over it.
// Landclass for current fragment, and up-to 4 neighboring landclasses - 2 used currently
int lc;
ivec4 lc_n;
int num_unique_neighbors = 0;
// Mix factor of base textures for 2 neighbour landclass(es)
vec4 mfact;
// Partial derivatives of s and t of ground texture coords for this fragment,
// with respect to window (screen space) x and y axes.
// Used to pick mipmap LoD levels, and turn off unneeded procedural detail
// dFdx and dFdy are packed in a vec4 so multiplying everything
// to scale takes 1 instruction slot.
vec4 dxdy_gc = vec4(dFdx(ground_tex_coord) , dFdy(ground_tex_coord));
get_landclass_id(tile_coord, dxdy_gc, lc, lc_n, num_unique_neighbors, mfact);
get_material(lc, ground_tex_coord, dxdy_gc, mat_shininess, mat_ambient, mat_diffuse, mat_specular, dxdy, st);
if (fg_photoScenery) {
texel = texture(landclass, vec2(gl_TexCoord[0].s, 1.0 - gl_TexCoord[0].t));
} else {
// Lookup the base texture texel for this fragment and any neighbors, with mixing
texel = get_mixed_texel(0, ground_tex_coord, lc, num_unique_neighbors, lc_n, mfact, dxdy_gc);
}
if ((water_shader == 1) && (fg_photoScenery == false) && fg_materialParams3[lc].x > 0.5) {
// This is a water fragment, so calculate the fragment color procedurally
fragColor = generateWaterTexel();
fragColor.rgb += getClusteredLightsContribution(eyePos.xyz, n, fragColor.rgb);
} else {
// Photoscenery or land fragment, so determine the shading and color normally
vec4 color = gl_Color * mat_ambient;
color.a = 1.0;
// Testing code: mix with green to show values of variables at each point
//vec4 green = vec4(0.0, 0.5, 0.0, 0.0);
//texel = mix(texel, green, (mfact[2]));
//mix_texel = texel;
//detail_texel = texel;
vec4 t = texel;
int flag = 1;
int mix_flag = 1;
float local_autumn_factor = texel.a;
if (fg_photoScenery) {
flag = 0;
mix_flag = 0;
}
float distortion_factor = 1.0;
vec2 stprime;
float noise_term;
float snow_alpha;
//float view_angle = abs(dot(normal, normalize(ecViewdir)));
if ((quality_level > 3)&&(msl_altitude +500.0 > snowlevel)) {
float sfactor;
snow_texel = vec4 (0.95, 0.95, 0.95, 1.0) * (0.9 + 0.1* noise_500m + 0.1* (1.0 - noise_10m) );
snow_texel.r = snow_texel.r * (0.9 + 0.05 * (noise_10m + noise_5m));
snow_texel.g = snow_texel.g * (0.9 + 0.05 * (noise_10m + noise_5m));
snow_texel.a = 1.0;
noise_term = 0.1 * (noise_500m-0.5);
sfactor = sqrt(2.0 * (1.0-steepness)/0.03) + abs(ct)/0.15;
noise_term = noise_term + 0.2 * (noise_50m -0.5) * (1.0 - smoothstep(18000.0*sfactor, 40000.0*sfactor, dist) ) ;
noise_term = noise_term + 0.3 * (noise_10m -0.5) * (1.0 - smoothstep(4000.0 * sfactor, 8000.0 * sfactor, dist) ) ;
if (dist < 3000.0*sfactor) {
noise_term = noise_term + 0.3 * (noise_5m -0.5) * (1.0 - smoothstep(1000.0 * sfactor, 3000.0 *sfactor, dist) );
}
snow_texel.a = snow_texel.a * 0.2+0.8* smoothstep(0.2,0.8, 0.3 +noise_term + snow_thickness_factor +0.0001*(msl_altitude -snowlevel) );
}
if ((tquality_level > 2) && (mix_flag == 1))
{
// Mix texture is material texture 15, which is mapped to the b channel of fg_textureLookup1
//int tex2 = int(fg_textureLookup1[lc].b * 255.0 + 0.5);
//mix_texel = texture(textureArray, vec3(gl_TexCoord[0].st * 1.3, tex2));
if (mix_texel.a < 0.1) { mix_flag = 0;}
//WS2: mix_texel = texture2D(mix_texture, gl_TexCoord[0].st * 1.3); // temp
mix_texel = lookup_ground_texture_array(4, st * 1.3, lc, dxdy * 1.3);
if (mix_texel.a <0.1) {mix_flag = 0;}
}
if (tquality_level > 3 && (flag == 1))
{
stprime = vec2 (0.86*gl_TexCoord[0].s + 0.5*gl_TexCoord[0].t, 0.5*gl_TexCoord[0].s - 0.86*gl_TexCoord[0].t);
//distortion_factor = 0.9375 + (1.0 * nvL[2]);
distortion_factor = 0.97 + 0.06 * noise_500m;
stprime = stprime * distortion_factor * 15.0;
if (quality_level > 4)
{
stprime = stprime + normalize(relPos).xy * 0.02 * (noise_10m + 0.5 * noise_5m - 0.75);
}
// Detail texture is material texture 11, which is mapped to the g channel of fg_textureLookup1
//int tex3 = int(fg_textureLookup1[lc].g * 255.0 + 0.5);
//detail_texel = texture(textureArray, vec3(stprime, tex3));
if (detail_texel.a < 0.1) { flag = 0;}
//WS2: detail_texel = texture2D(detail_texture, stprime); // temp
vec4 dxdy_prime = vec4(dFdx(stprime), dFdy(stprime));
detail_texel = lookup_ground_texture_array(5, stprime, lc, dxdy_prime);
}
// texture preparation according to detail level
// mix in hires texture patches
float dist_fact;
float nSum;
float mix_factor;
float transition_model = fg_materialParams1[lc].r;
float hires_overlay_bias = fg_materialParams1[lc].g;
if (tquality_level > 2) {
// first the second texture overlay
// transition model 0: random patch overlay without any gradient information
// transition model 1: only gradient-driven transitions, no randomness
if (mix_flag == 1) {
// Random patch overlay weighting with noise
nSum = 0.18 * (2.0 * noise_2000m + 2.0 * noise_1500m + noise_500m);
// Increase the weighting for the mix_texel if more gradient-driven.
nSum = mix(nSum, 0.5, max(0.0, 2.0 * (transition_model - 0.5)));
// Add the gradient element
nSum = nSum + 0.4 * (1.0 -smoothstep(0.9,0.95, abs(steepness)+ 0.05 * (noise_50m - 0.5))) * min(1.0, 2.0 * transition_model);
mix_factor = smoothstep(0.5, 0.54, nSum);
texel = mix(texel, mix_texel, mix_factor);
local_autumn_factor = texel.a;
}
}
if (tquality_level > 3) {
// then the detail texture overlay
if (dist < 40000.0)
{
if (flag == 1) {
//noise_50m = Noise2D(rawPos.xy, 50.0);
//noise_250m = Noise2D(rawPos.xy, 250.0);
dist_fact = 0.1 * smoothstep(15000.0,40000.0, dist) - 0.03 * (1.0 - smoothstep(500.0,5000.0, dist));
nSum = ((1.0 -noise_2000m) + noise_1500m + 2.0 * noise_250m +noise_50m)/5.0;
nSum = nSum - 0.08 * (1.0 -smoothstep(0.9,0.95, abs(steepness)));
mix_factor = smoothstep(0.47, 0.54, nSum +hires_overlay_bias - dist_fact);
if (mix_factor > 0.8) {mix_factor = 0.8;}
texel = mix(texel, detail_texel,mix_factor);
local_autumn_factor = texel.a;
}
}
}
// autumn colors
float autumn_factor = season * 2.0 * (1.0 - local_autumn_factor) ;
texel.r = min(1.0, (1.0 + 2.5 * autumn_factor) * texel.r);
texel.g = texel.g;
texel.b = max(0.0, (1.0 - 4.0 * autumn_factor) * texel.b);
if (local_autumn_factor < 1.0)
{
intensity = length(texel.rgb) * (1.0 - 0.5 * smoothstep(1.1,2.0,season));
texel.rgb = intensity * normalize(mix(texel.rgb, vec3(0.23,0.17,0.08), smoothstep(1.1,2.0, season)));
}
const vec4 dust_color = vec4 (0.76, 0.71, 0.56, 1.0);
const vec4 lichen_color = vec4 (0.17, 0.20, 0.06, 1.0);;
//float snow_alpha;
if (quality_level > 3)
{
// mix vegetation
texel = mix(texel, lichen_color, 0.4 * lichen_cover_factor + 0.8 * lichen_cover_factor * 0.5 * (noise_10m + (1.0 - noise_5m)) );
// mix dust
texel = mix(texel, dust_color, clamp(0.5 * dust_cover_factor + 3.0 * dust_cover_factor * (((noise_1500m - 0.5) * 0.125)+0.125 ),0.0, 1.0) );
// mix snow
if (msl_altitude +500.0 > snowlevel)
{
snow_alpha = smoothstep(0.75, 0.85, abs(steepness));
//texel = mix(texel, snow_texel, texel_snow_fraction);
texel = mix(texel, snow_texel, snow_texel.a* smoothstep(snowlevel, snowlevel+200.0, snow_alpha * (msl_altitude)+ (noise_2000m + 0.1 * noise_10m -0.55) *400.0));
}
}
else if (msl_altitude +500.0 > snowlevel)
{
float snow_alpha = 0.5+0.5* smoothstep(0.2,0.8, 0.3 + snow_thickness_factor +0.0001*(msl_altitude -snowlevel) );
// texel = vec4(dot(vec3(0.2989, 0.5870, 0.1140), texel.rgb));
texel = mix(texel, vec4(1.0), snow_alpha* smoothstep(snowlevel, snowlevel+200.0, (msl_altitude)));
}
// get distribution of water when terrain is wet
float water_threshold1;
float water_threshold2;
float water_factor =0.0;
if ((dist < 5000.0)&& (quality_level > 3) && (wetness>0.0))
{
water_threshold1 = 1.0-0.5* wetness;
water_threshold2 = 1.0 - 0.3 * wetness;
water_factor = smoothstep(water_threshold1, water_threshold2 , (0.3 * (2.0 * (1.0-noise_10m) + (1.0 -noise_5m)) * (1.0 - smoothstep(2000.0, 5000.0, dist))) - 5.0 * (1.0 -steepness));
}
// darken wet terrain
texel.rgb = texel.rgb * (1.0 - 0.6 * wetness);
// light computations
vec4 light_specular = gl_LightSource[0].specular;
// If gl_Color.a == 0, this is a back-facing polygon and the
// normal should be reversed.
//n = (2.0 * gl_Color.a - 1.0) * normal;
n = normal;//vec3 (nvec.x, nvec.y, sqrt(1.0 -pow(nvec.x,2.0) - pow(nvec.y,2.0) ));
n = normalize(n);
NdotL = dot(n, lightDir);
if ((tquality_level > 3) && (mix_flag ==1)&& (dist < 2000.0) && (quality_level > 4))
{
noisegrad_10m = (noise_10m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),10.0))/0.05;
noisegrad_5m = (noise_5m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),5.0))/0.05;
NdotL = NdotL + 1.0 * (noisegrad_10m + 0.5* noisegrad_5m) * mix_factor/0.8 * (1.0 - smoothstep(1000.0, 2000.0, dist));
}
if (NdotL > 0.0) {
float shadowmap = getShadowing();
vec4 diffuse_term = light_diffuse_comp * mat_diffuse;
color += diffuse_term * NdotL * shadowmap;
NdotHV = max(dot(n, halfVector), 0.0);
if (mat_shininess > 0.0)
specular.rgb = (mat_specular.rgb
* light_specular.rgb
* pow(NdotHV, mat_shininess)
* shadowmap);
}
color.a = 1.0;//diffuse_term.a;
// This shouldn't be necessary, but our lighting becomes very
// saturated. Clamping the color before modulating by the texture
// is closer to what the OpenGL fixed function pipeline does.
color = clamp(color, 0.0, 1.0);
fragColor = color * texel + specular;
fragColor.rgb += getClusteredLightsContribution(eyePos.xyz, n, texel.rgb);
}
float lightArg = (terminator-yprime_alt)/100000.0;
vec3 hazeColor = get_hazeColor(lightArg);
gl_FragColor = applyHaze(fragColor, hazeColor, vec3(0.0), ct, hazeLayerAltitude, visibility, avisibility, dist, lightArg, mie_angle);
// Testing phase controls:
if (remove_haze_and_lighting == 1)
{
gl_FragColor = texel;
}
}