veloren/assets/voxygen/shaders/include/sky.glsl
2019-11-19 19:09:22 +00:00

293 lines
7.7 KiB
GLSL

#include <random.glsl>
uniform sampler2D t_noise;
const float PI = 3.141592;
const vec3 SKY_DAY_TOP = vec3(0.1, 0.2, 0.9);
const vec3 SKY_DAY_MID = vec3(0.02, 0.08, 0.8);
const vec3 SKY_DAY_BOT = vec3(0.02, 0.1, 0.3);
const vec3 DAY_LIGHT = vec3(1.2, 1.0, 1.0);
const vec3 SUN_HALO_DAY = vec3(0.35, 0.35, 0.0);
const vec3 SKY_DUSK_TOP = vec3(0.06, 0.1, 0.20);
const vec3 SKY_DUSK_MID = vec3(0.35, 0.1, 0.15);
const vec3 SKY_DUSK_BOT = vec3(0.0, 0.1, 0.13);
const vec3 DUSK_LIGHT = vec3(3.0, 1.5, 0.3);
const vec3 SUN_HALO_DUSK = vec3(0.6, 0.1, 0.0);
const vec3 SKY_NIGHT_TOP = vec3(0.001, 0.001, 0.0025);
const vec3 SKY_NIGHT_MID = vec3(0.001, 0.005, 0.02);
const vec3 SKY_NIGHT_BOT = vec3(0.002, 0.002, 0.005);
const vec3 NIGHT_LIGHT = vec3(0.002, 0.01, 0.03);
vec3 get_sun_dir(float time_of_day) {
const float TIME_FACTOR = (PI * 2.0) / (3600.0 * 24.0);
float sun_angle_rad = time_of_day * TIME_FACTOR;
return vec3(sin(sun_angle_rad), 0.0, cos(sun_angle_rad));
}
vec3 get_moon_dir(float time_of_day) {
const float TIME_FACTOR = (PI * 2.0) / (3600.0 * 24.0);
float moon_angle_rad = time_of_day * TIME_FACTOR;
return normalize(-vec3(sin(moon_angle_rad), 0.0, cos(moon_angle_rad) - 0.5));
}
const float PERSISTENT_AMBIANCE = 0.1;
float get_sun_brightness(vec3 sun_dir) {
return max(-sun_dir.z + 0.6, 0.0) * 0.9;
}
float get_moon_brightness(vec3 moon_dir) {
return max(-moon_dir.z + 0.6, 0.0) * 0.07;
}
vec3 get_sun_color(vec3 sun_dir) {
return mix(
mix(
DUSK_LIGHT,
NIGHT_LIGHT,
max(sun_dir.z, 0)
),
DAY_LIGHT,
max(-sun_dir.z, 0)
);
}
vec3 get_moon_color(vec3 moon_dir) {
return vec3(0.15, 0.15, 1.5);
}
void get_sun_diffuse(vec3 norm, float time_of_day, out vec3 light, out vec3 diffuse_light, out vec3 ambient_light, float diffusion) {
const float SUN_AMBIANCE = 0.1;
vec3 sun_dir = get_sun_dir(time_of_day);
vec3 moon_dir = get_moon_dir(time_of_day);
float sun_light = get_sun_brightness(sun_dir);
float moon_light = get_moon_brightness(moon_dir);
// clamp() changed to max() as sun_dir.z is produced from a cos() function and therefore never greater than 1
vec3 sun_color = get_sun_color(sun_dir);
vec3 moon_color = get_moon_color(moon_dir);
vec3 sun_chroma = sun_color * sun_light;
vec3 moon_chroma = moon_color * moon_light;
light = sun_chroma + moon_chroma + PERSISTENT_AMBIANCE;
diffuse_light =
sun_chroma * mix(1.0, max(dot(-norm, sun_dir) * 0.6 + 0.4, 0.0), diffusion) +
moon_chroma * mix(1.0, pow(max(dot(-norm, moon_dir), 0.0), 2.0), diffusion) +
PERSISTENT_AMBIANCE;
ambient_light = vec3(SUN_AMBIANCE * sun_light + moon_light);
}
// This has been extracted into a function to allow quick exit when detecting a star.
float is_star_at(vec3 dir) {
float star_scale = 30.0;
for (int i = 0; i < 2; i ++) {
for (int j = 0; j < 2; j ++) {
for (int k = 0; k < 2; k ++) {
// Star positions
vec3 pos = (floor(dir * star_scale) + vec3(i, j, k) - vec3(0.5)) / star_scale;
// Noisy offsets
pos += (3.0 / star_scale) * rand_perm_3(pos);
// Find distance to fragment
float dist = length(normalize(pos) - dir);
// Star threshold
if (dist < 0.0015) {
return 1.0;
}
}
}
}
return 0.0;
}
const float CLOUD_AVG_HEIGHT = 900.0;
const float CLOUD_HEIGHT_MIN = CLOUD_AVG_HEIGHT - 100.0;
const float CLOUD_HEIGHT_MAX = CLOUD_AVG_HEIGHT + 100.0;
const float CLOUD_THRESHOLD = 0.3;
const float CLOUD_SCALE = 1.0;
const float CLOUD_DENSITY = 100.0;
float spow(float x, float e) {
return sign(x) * pow(abs(x), e);
}
float vsum(vec3 v) {
return v.x + v.y + v.z;
}
vec2 cloud_at(vec3 pos) {
float tick_offs = 0.0
+ texture(t_noise, pos.xy * 0.0001).x
+ texture(t_noise, pos.xy * 0.000003).x * 10.0;
float value = (
0.0
+ texture(t_noise, pos.xy / CLOUD_SCALE * 0.0003 - tick.x * 0.003 + tick_offs).x
+ texture(t_noise, pos.xy / CLOUD_SCALE * 0.0009 + tick.x * 0.01).x * 0.5
+ texture(t_noise, pos.xy / CLOUD_SCALE * 0.0025 - tick.x * 0.02).x * 0.25
+ texture(t_noise, pos.xy / CLOUD_SCALE * 0.0075 - tick.x * 0.03).x * 0.07
) / 2.85;
float density = max((value - CLOUD_THRESHOLD) - abs(pos.z - CLOUD_AVG_HEIGHT) / 800.0, 0.0) * CLOUD_DENSITY;
float shade = 0.5 - min(pow(max(CLOUD_AVG_HEIGHT - pos.z, 0.0), 0.5), 1.0) / 1.0;
return vec2(shade, density / (1.0 + vsum(abs(pos - cam_pos.xyz)) / 10000));
}
vec4 get_cloud_color(vec3 dir, float time_of_day, float max_dist) {
const float INCR = 0.05;
float mind = (CLOUD_HEIGHT_MIN - cam_pos.z) / dir.z;
float maxd = (CLOUD_HEIGHT_MAX - cam_pos.z) / dir.z;
float start = max(min(mind, maxd), 0.0);
float delta = abs(mind - maxd);
float incr = min(INCR + start / 100000.0, INCR * 2.0);
float fuzz = texture(t_noise, dir.xy * 1000000.0).x * 1.75 * incr * delta;
if (delta <= 0.0) {
return vec4(0);
}
float cloud_shade = 1.0;
float passthrough = 1.0;
for (float d = 0.0; d < 1.0; d += incr) {
float dist = start + d * delta + fuzz;
vec3 pos = cam_pos.xyz + dir * dist;
vec2 sample = cloud_at(pos);
float factor;
if (dist < max_dist) {
factor = 1.0;
} else {
factor = incr * (dist - max_dist) / delta;
}
float integral = sample.y * incr * factor;
passthrough *= 1.0 - integral;
cloud_shade = mix(cloud_shade, sample.x, passthrough * integral);
if (factor < 1.0) {
break;
}
}
return vec4(vec3(cloud_shade), 1.0 - passthrough / (1.0 + delta * 0.0003));
}
vec3 get_sky_color(vec3 dir, float time_of_day, vec3 f_pos, bool with_stars) {
// Sky color
vec3 sun_dir = get_sun_dir(time_of_day);
vec3 moon_dir = get_moon_dir(time_of_day);
// Add white dots for stars. Note these flicker and jump due to FXAA
float star = 0.0;
if (with_stars) {
star = is_star_at(dir);
}
// Replaced all clamp(sun_dir, 0, 1) with max(sun_dir, 0) because sun_dir is calculated from sin and cos, which are never > 1
vec3 sky_top = mix(
mix(
SKY_DUSK_TOP + star,
SKY_NIGHT_TOP + star,
max(pow(sun_dir.z, 0.2), 0)
),
SKY_DAY_TOP,
max(-sun_dir.z, 0)
);
vec3 sky_mid = mix(
mix(
SKY_DUSK_MID,
SKY_NIGHT_MID,
max(pow(sun_dir.z, 0.2), 0)
),
SKY_DAY_MID,
max(-sun_dir.z, 0)
);
vec3 sky_bot = mix(
mix(
SKY_DUSK_BOT,
SKY_NIGHT_BOT,
max(pow(sun_dir.z, 0.2), 0)
),
SKY_DAY_BOT,
max(-sun_dir.z, 0)
);
vec3 sky_color = mix(
mix(
sky_mid,
sky_bot,
pow(max(-dir.z, 0), 0.4)
),
sky_top,
max(dir.z, 0)
);
// Sun
const vec3 SUN_SURF_COLOR = vec3(1.5, 0.9, 0.35) * 200.0;
vec3 sun_halo_color = mix(
SUN_HALO_DUSK,
SUN_HALO_DAY,
max(-sun_dir.z, 0)
);
vec3 sun_halo = pow(max(dot(dir, -sun_dir) + 0.1, 0.0), 8.0) * sun_halo_color;
vec3 sun_surf = pow(max(dot(dir, -sun_dir) - 0.001, 0.0), 3000.0) * SUN_SURF_COLOR;
vec3 sun_light = (sun_halo + sun_surf) * clamp(dir.z * 10.0, 0, 1);
// Moon
const vec3 MOON_SURF_COLOR = vec3(0.7, 1.0, 1.5) * 500.0;
vec3 moon_halo_color = vec3(0.015, 0.015, 0.03);
vec3 moon_halo = pow(max(dot(dir, -moon_dir) + 0.1, 0.0), 8.0) * moon_halo_color;
vec3 moon_surf = pow(max(dot(dir, -moon_dir) - 0.001, 0.0), 3000.0) * MOON_SURF_COLOR;
vec3 moon_light = clamp(moon_halo + moon_surf, vec3(0), vec3(clamp(dir.z * 3.0, 0, 1)));
// Clouds
vec4 clouds = get_cloud_color(dir, time_of_day, distance(cam_pos.xyz, f_pos));
clouds.rgb *= get_sun_brightness(sun_dir) * (sun_halo + get_sun_color(sun_dir)) + get_moon_brightness(moon_dir) * (moon_halo + get_moon_color(moon_dir));
return mix(sky_color + sun_light + moon_light, clouds.rgb, clouds.a);
}
float fog(vec3 f_pos, vec3 focus_pos, uint medium) {
float fog_radius = view_distance.x;
float mist_radius = 10000000.0;
float min_fog = 0.5;
float max_fog = 1.0;
if (medium == 1u) {
mist_radius = 96.0;
min_fog = 0.0;
}
float fog = distance(f_pos.xy, focus_pos.xy) / fog_radius;
float mist = distance(f_pos, focus_pos) / mist_radius;
return pow(clamp((max(fog, mist) - min_fog) / (max_fog - min_fog), 0.0, 1.0), 1.7);
}