d723b0b518
Use Uniform Arrays instead of Texture1D. Use ambient/diffuse/specular/shininess material properties consistently across all WS30 shaders. Use consistent shading model for photoscenery vs. landclass to minimize visual difference.
479 lines
15 KiB
C++
479 lines
15 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;
|
|
|
|
//
|
|
// End of test phase controls
|
|
//////////////////////////////////////////////////////////////////
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// Ambient term comes in gl_Color.rgb.
|
|
varying vec4 light_diffuse_comp;
|
|
varying vec3 normal;
|
|
varying vec3 relPos;
|
|
|
|
uniform sampler2D landclass;
|
|
uniform sampler2DArray textureArray;
|
|
|
|
varying float yprime_alt;
|
|
varying float mie_angle;
|
|
varying vec4 ecPosition;
|
|
|
|
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 cloud_self_shading;
|
|
|
|
// Passed from VPBTechnique, not the Effect
|
|
uniform int tile_level;
|
|
uniform float tile_width;
|
|
uniform float tile_height;
|
|
uniform bool photoScenery;
|
|
uniform vec4 dimensionsArray[128];
|
|
uniform vec4 ambientArray[128];
|
|
uniform vec4 diffuseArray[128];
|
|
uniform vec4 specularArray[128];
|
|
|
|
const float EarthRadius = 5800000.0;
|
|
const float terminator_width = 200000.0;
|
|
|
|
float alt;
|
|
float eShade;
|
|
|
|
float fog_func (in float targ, in float alt);
|
|
vec3 get_hazeColor(in float light_arg);
|
|
vec3 filter_combined (in vec3 color) ;
|
|
|
|
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);
|
|
|
|
// Not used
|
|
float luminance(vec3 color)
|
|
{
|
|
return dot(vec3(0.212671, 0.715160, 0.072169), color);
|
|
}
|
|
|
|
|
|
//////////////////////////
|
|
// 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);
|
|
|
|
// These functions, and other function they depend on, are defined
|
|
// in ws30-ALS-landclass-search.frag.
|
|
|
|
|
|
// 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);
|
|
|
|
|
|
// 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.
|
|
|
|
vec4 lookup_ground_texture_array(in vec2 tile_coord, in int landclass_id, in vec2 dx, in vec2 dy);
|
|
|
|
|
|
// 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 werighting the influences of nearby landclasses
|
|
void get_landclass_id(in vec2 tile_coord,
|
|
const in float landclass_texel_size_m, in vec2 dx, in vec2 dy,
|
|
out int landclass_id, out ivec4 neighbor_landclass_ids,
|
|
out int num_unique_neighbors,out vec4 mix_factor
|
|
);
|
|
|
|
|
|
// End Test-phase code
|
|
////////////////////////
|
|
|
|
|
|
void main()
|
|
{
|
|
|
|
|
|
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;
|
|
vec4 texel;
|
|
vec4 fragColor;
|
|
vec4 specular = vec4(0.0);
|
|
float intensity;
|
|
|
|
|
|
|
|
// 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;
|
|
|
|
|
|
const float landclass_texel_size_m = 25.0;
|
|
|
|
// Partial derivatives of s and t 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
|
|
vec2 dx = dFdx(tile_coord);
|
|
vec2 dy = dFdy(tile_coord);
|
|
|
|
get_landclass_id(tile_coord, landclass_texel_size_m, dx, dy,
|
|
lc, lc_n, num_unique_neighbors, mfact);
|
|
|
|
// The landclass id is used to index into arrays containing
|
|
// material parameters and textures for the landclass as
|
|
// defined in the regional definitions
|
|
float index = float(lc)/512.0;
|
|
vec4 index_n = vec4(lc_n)/512.0;
|
|
|
|
// Material properties.
|
|
vec4 mat_diffuse, mat_ambient, mat_specular;
|
|
float mat_shininess;
|
|
|
|
if (photoScenery) {
|
|
mat_ambient = vec4(1.0,1.0,1.0,1.0);
|
|
mat_diffuse = vec4(1.0,1.0,1.0,1.0);
|
|
mat_specular = vec4(0.1, 0.1, 0.1, 1.0);
|
|
mat_shininess = 1.2;
|
|
|
|
texel = texture(landclass, vec2(gl_TexCoord[0].s, 1.0 - gl_TexCoord[0].t));
|
|
} else {
|
|
// Color Mode is always AMBIENT_AND_DIFFUSE, which means
|
|
// using a base colour of white for ambient/diffuse,
|
|
// rather than the material color from ambientArray/diffuseArray.
|
|
mat_ambient = vec4(1.0,1.0,1.0,1.0);
|
|
mat_diffuse = vec4(1.0,1.0,1.0,1.0);
|
|
mat_specular = specularArray[lc];
|
|
mat_shininess = dimensionsArray[lc].z;
|
|
|
|
// Look up ground textures by indexing into the texture array.
|
|
// Different textures are stretched along the ground to different
|
|
// lengths along each axes as set by <xsize> and <ysize>
|
|
// regional definitions parameters
|
|
|
|
// Look up texture coordinates and scale of ground textures
|
|
// Landclass for this fragment
|
|
texel = lookup_ground_texture_array(tile_coord, lc, dx, dy);
|
|
|
|
// Mix texels - to work consistently it needs a more preceptual interpolation than mix()
|
|
if (num_unique_neighbors != 0)
|
|
{
|
|
// Closest neighbor landclass
|
|
vec4 texel_closest = lookup_ground_texture_array(tile_coord, lc_n[0], dx, dy);
|
|
|
|
// Neighbor contributions
|
|
vec4 texel_nc=texel_closest;
|
|
|
|
if (num_unique_neighbors > 1)
|
|
{
|
|
// 2nd Closest neighbor landclass
|
|
vec4 texel_2nd_closest = lookup_ground_texture_array(tile_coord, lc_n[1],
|
|
dx, dy);
|
|
|
|
texel_nc = mix(texel_closest, texel_2nd_closest, mfact[1]);
|
|
}
|
|
|
|
texel = mix(texel, texel_nc, mfact[0]);
|
|
}
|
|
}
|
|
|
|
vec4 color = mat_ambient * (gl_LightModel.ambient + gl_LightSource[0].ambient);
|
|
|
|
// Testing code:
|
|
// Use rlc even when looking up textures to recreate the extra performance hit
|
|
// so any performance difference between the two is due to the texture lookup
|
|
// color = color+0.00001*float(get_random_landclass(tile_coord.st, tile_size));
|
|
|
|
float effective_scattering = min(scattering, cloud_self_shading);
|
|
|
|
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 = normalize(normal);
|
|
|
|
|
|
NdotL = dot(n, lightDir);
|
|
vec4 diffuse_term = light_diffuse_comp * mat_diffuse;
|
|
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, gl_FrontMaterial.shininess)
|
|
* shadowmap);
|
|
}
|
|
color.a = 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);
|
|
|
|
|
|
// 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]));
|
|
|
|
|
|
fragColor = color * texel + specular;
|
|
fragColor.rgb += getClusteredLightsContribution(ecPosition.xyz, n, texel.rgb);
|
|
|
|
// here comes the terrain haze model
|
|
float delta_z = hazeLayerAltitude - eye_alt;
|
|
float dist = length(relPos);
|
|
|
|
float mvisibility = min(visibility,avisibility);
|
|
|
|
if (dist > 0.04 * mvisibility)
|
|
{
|
|
|
|
alt = eye_alt;
|
|
|
|
float transmission;
|
|
float vAltitude;
|
|
float delta_zv;
|
|
float H;
|
|
float distance_in_layer;
|
|
float transmission_arg;
|
|
|
|
// angle with horizon
|
|
float ct = dot(vec3(0.0, 0.0, 1.0), relPos)/dist;
|
|
|
|
|
|
// we solve the geometry what part of the light path is attenuated normally and what is through the haze layer
|
|
if (delta_z > 0.0) // we're inside the layer
|
|
{
|
|
if (ct < 0.0) // we look down
|
|
{
|
|
distance_in_layer = dist;
|
|
vAltitude = min(distance_in_layer,mvisibility) * ct;
|
|
delta_zv = delta_z - vAltitude;
|
|
}
|
|
else // we may look through upper layer edge
|
|
{
|
|
H = dist * ct;
|
|
if (H > delta_z) {distance_in_layer = dist/H * delta_z;}
|
|
else {distance_in_layer = dist;}
|
|
vAltitude = min(distance_in_layer,visibility) * ct;
|
|
delta_zv = delta_z - vAltitude;
|
|
}
|
|
}
|
|
else // we see the layer from above, delta_z < 0.0
|
|
{
|
|
H = dist * -ct;
|
|
if (H < (-delta_z)) // we don't see into the layer at all, aloft visibility is the only fading
|
|
{
|
|
distance_in_layer = 0.0;
|
|
delta_zv = 0.0;
|
|
}
|
|
else
|
|
{
|
|
vAltitude = H + delta_z;
|
|
distance_in_layer = vAltitude/H * dist;
|
|
vAltitude = min(distance_in_layer,visibility) * (-ct);
|
|
delta_zv = vAltitude;
|
|
}
|
|
}
|
|
|
|
|
|
// ground haze cannot be thinner than aloft visibility in the model,
|
|
// so we need to use aloft visibility otherwise
|
|
transmission_arg = (dist-distance_in_layer)/avisibility;
|
|
|
|
float eqColorFactor;
|
|
|
|
|
|
|
|
if (visibility < avisibility)
|
|
{
|
|
transmission_arg = transmission_arg + (distance_in_layer/visibility);
|
|
// this combines the Weber-Fechner intensity
|
|
eqColorFactor = 1.0 - 0.1 * delta_zv/visibility - (1.0 -effective_scattering);
|
|
|
|
}
|
|
else
|
|
{
|
|
transmission_arg = transmission_arg + (distance_in_layer/avisibility);
|
|
// this combines the Weber-Fechner intensity
|
|
eqColorFactor = 1.0 - 0.1 * delta_zv/avisibility - (1.0 -effective_scattering);
|
|
}
|
|
|
|
transmission = fog_func(transmission_arg, alt);
|
|
|
|
// there's always residual intensity, we should never be driven to zero
|
|
if (eqColorFactor < 0.2) {eqColorFactor = 0.2;}
|
|
|
|
float lightArg = (terminator-yprime_alt)/100000.0;
|
|
vec3 hazeColor = get_hazeColor(lightArg);
|
|
|
|
// now dim the light for haze
|
|
eShade = 1.0 - 0.9 * smoothstep(-terminator_width+ terminator, terminator_width + terminator, yprime_alt);
|
|
|
|
// Mie-like factor
|
|
if (lightArg < 10.0)
|
|
{intensity = length(hazeColor);
|
|
float mie_magnitude = 0.5 * smoothstep(350000.0, 150000.0, terminator-sqrt(2.0 * EarthRadius * terrain_alt));
|
|
hazeColor = intensity * ((1.0 - mie_magnitude) + mie_magnitude * mie_angle) * normalize(mix(hazeColor, vec3 (0.5, 0.58, 0.65), mie_magnitude * (0.5 - 0.5 * mie_angle)) );
|
|
}
|
|
|
|
// high altitude desaturation of the haze color
|
|
|
|
intensity = length(hazeColor);
|
|
hazeColor = intensity * normalize (mix(hazeColor, intensity * vec3 (1.0,1.0,1.0), 0.7* smoothstep(5000.0, 50000.0, alt)));
|
|
|
|
// blue hue of haze
|
|
|
|
hazeColor.x = hazeColor.x * 0.83;
|
|
hazeColor.y = hazeColor.y * 0.9;
|
|
|
|
|
|
// additional blue in indirect light
|
|
float fade_out = max(0.65 - 0.3 *overcast, 0.45);
|
|
intensity = length(hazeColor);
|
|
hazeColor = intensity * normalize(mix(hazeColor, 1.5* shadedFogColor, 1.0 -smoothstep(0.25, fade_out,eShade) ));
|
|
|
|
// change haze color to blue hue for strong fogging
|
|
//intensity = length(hazeColor);
|
|
hazeColor = intensity * normalize(mix(hazeColor, shadedFogColor, (1.0-smoothstep(0.5,0.9,eqColorFactor))));
|
|
|
|
|
|
// reduce haze intensity when looking at shaded surfaces, only in terminator region
|
|
|
|
float shadow = mix( min(1.0 + dot(normal,lightDir),1.0), 1.0, 1.0-smoothstep(0.1, 0.4, transmission));
|
|
hazeColor = mix(shadow * hazeColor, hazeColor, 0.3 + 0.7* smoothstep(250000.0, 400000.0, terminator));
|
|
|
|
// don't let the light fade out too rapidly
|
|
lightArg = (terminator + 200000.0)/100000.0;
|
|
float minLightIntensity = min(0.2,0.16 * lightArg + 0.5);
|
|
vec3 minLight = minLightIntensity * vec3 (0.2, 0.3, 0.4);
|
|
hazeColor *= eqColorFactor * eShade;
|
|
hazeColor.rgb = max(hazeColor.rgb, minLight.rgb);
|
|
|
|
// determine the right mix of transmission and haze
|
|
|
|
|
|
// Testing phase controls
|
|
if (reduce_haze_without_removing_calculation_overhead == 1)
|
|
{
|
|
transmission = 1.0 - (transmission/1000000.0);
|
|
}
|
|
|
|
|
|
|
|
fragColor.rgb = mix(hazeColor, fragColor.rgb,transmission);
|
|
}
|
|
|
|
fragColor.rgb = filter_combined(fragColor.rgb);
|
|
|
|
gl_FragColor = fragColor;
|
|
|
|
|
|
|
|
// Testing phase controls:
|
|
if (remove_haze_and_lighting == 1)
|
|
{
|
|
gl_FragColor = texel;
|
|
}
|
|
|
|
|
|
|
|
}
|