- Edited
im trying to write a skyshader
heres what i have so far;
shader_type sky;
render_mode use_quarter_res_pass;
group_uniforms sky;
uniform vec3 top_color : source_color = vec3( 0.1, 0.6, 1.0 );
uniform vec3 bottom_color : source_color = vec3( 0.4, 0.8, 1.0 );
group_uniforms horizon;
uniform vec3 horizon_color : source_color = vec3( 0.0, 0.7, 0.8 );
uniform float horizon_blur : hint_range( 0.0, 1.0, 0.01 ) = 0.05;
group_uniforms sun; // First DirectionalLight3D will be the sun
uniform vec3 sun_color : source_color = vec3( 10.0, 8.0, 1.0 );
uniform float sun_size : hint_range( 0.01, 1.0 ) = 0.2;
uniform float sun_blur : hint_range( 0.01, 20.0 ) = 10.0;
group_uniforms clouds;
uniform vec3 clouds_edge_color : source_color = vec3( 0.8, 0.8, 0.98 );
uniform vec3 clouds_main_color : source_color = vec3( 1.0, 1.0, 1.00 );
uniform float clouds_speed : hint_range( 0.0, 20.0, 0.01 ) = 2.0;
uniform float clouds_scale : hint_range( 0.0, 4.0, 0.01 ) = 1.0;
uniform float clouds_cutoff : hint_range( 0.0, 1.0, 0.01 ) = 0.3;
uniform float clouds_weight : hint_range( 0.0, 1.0, 0.01 ) = 0.0;
uniform float clouds_blur : hint_range( 0.0, 1.0, 0.01 ) = 0.25;
const mat2 m = mat2(vec2( 1.6, 1.2), vec2(-1.2, 1.6));
vec2 hash( vec2 p ) {
p = vec2(dot(p, vec2(127.1, 311.7)), dot(p, vec2(269.5, 183.3)));
return -1.0 + 2.0 * fract(sin(p) * 43758.5453123);
}
float noise( in vec2 p ) {
const float K1 = 0.366025404; // (sqrt(3)-1)/2;
const float K2 = 0.211324865; // (3-sqrt(3))/6;
vec2 i = floor(p + (p.x + p.y)*K1);
vec2 a = p - i + (i.x + i.y) * K2;
vec2 o = (a.x > a.y) ? vec2(1.0, 0.0) : vec2(0.0, 1.0);
vec2 b = a - o + K2;
vec2 c = a - 1.0 + 2.0 * K2;
vec3 h = max(0.5 - vec3(dot(a, a), dot(b, b), dot(c, c)), 0.0 );
vec3 n = h * h * h * h * vec3(dot(a, hash(i + 0.0)), dot(b, hash(i + o)), dot(c, hash(i + 1.0)));
return dot(n, vec3(70.0));
}
float fbm(vec2 n) {
float total = 0.0, amplitude = 0.1;
for (int i = 0; i < 7; i++) {
total += noise(n) * amplitude;
n = m * n;
amplitude *= 0.4;
}
return total;
}
void sky()
{
float time = TIME;
vec2 _sky_uv = EYEDIR.xz / sqrt( EYEDIR.y );
float _eyedir_y = abs( sin( EYEDIR.y * PI * 0.5 ));
//SKYCOLOR
vec3 _sky_color = mix(bottom_color, top_color, _eyedir_y );
_sky_color = mix( _sky_color, vec3( 0.0 ), clamp(( 0.7 - clouds_cutoff ) * clouds_weight, 0.0, 1.0 ));
COLOR = _sky_color;
//HORIZON
float _horizon_amount = 0.0;
if( EYEDIR.y < 0.0 )
{
_horizon_amount = clamp( abs( EYEDIR.y ) / horizon_blur, 0.0, 1.0 );
vec3 _horizon_color = mix( horizon_color, _sky_color, 0.9 );
_horizon_color = mix( _horizon_color, vec3( 0.0 ), ( 1.0 - clouds_cutoff ) * clouds_weight * 0.7 );
COLOR = mix( COLOR, _horizon_color, _horizon_amount );
}
//SUN
float _sun_distance = 0.0;
if( LIGHT0_ENABLED )
{
_sun_distance = distance( EYEDIR, LIGHT0_DIRECTION );
// Bigger sun near the horizon
float _sun_size = sun_size + cos( LIGHT0_DIRECTION.y * PI ) * sun_size * 0.25;
// Finding sun disc and edge blur
float _sun_amount = clamp(( 1.0 - _sun_distance / _sun_size ) / sun_blur, 0.0, 1.0 );
if( _sun_amount > 0.0 )
{
vec3 _sun_color = sun_color;
_sun_amount *= 1.0 - _horizon_amount;
// Leveling the "glow" in color
if( _sun_color.r > 1.0 || _sun_color.g > 1.0 || _sun_color.b > 1.0 )
_sun_color *= _sun_amount;
COLOR = mix( COLOR, _sun_color, _sun_amount );
}
}
//CLOUDS
if( EYEDIR.y > 0.0 )
{
vec3 normal = normalize(EYEDIR);
vec3 plane_intersect = normal / (normal.y + clouds_cutoff);
vec2 p = plane_intersect.xz;
p.y *= -1.0;
vec2 uv = p;
time = time * clouds_speed;
float q = fbm(uv * clouds_scale * 0.5);
//ridged noise shape
float r = 0.0;
time = TIME * clouds_speed * 0.3;
uv *= clouds_scale;
uv -= q - time;
float weight = 0.8;
for(int i = 0; i < 8; i++){
r += abs(weight*noise( uv ));
uv = m*uv + time;
weight *= 0.7;
}
//noise shape
float f = 0.0;
time = TIME * clouds_speed * 0.4;
uv = p;
uv *= clouds_scale;
uv -= q - time;
weight = 0.7;
for(int i = 0; i < 8; i++){
f += weight*noise( uv );
uv = m*uv + time;
weight *= 0.6;
}
f *= r + f;
//noise colour
float c = 0.0;
time = TIME * clouds_speed * 2.0;
uv = p;
uv *= clouds_scale * 1.5;
uv -= q - time;
weight = 0.4;
for(int i = 0; i < 7; i++){
c += weight*noise( uv );
uv = m*uv + time;
weight *= 0.6;
}
//noise ridge colour
float c1 = 0.0;
time = TIME * clouds_speed * 5.0;
uv = p;
uv *= clouds_scale * 3.0;
uv -= q - time;
weight = 0.4;
for (int i = 0; i < 7; i++){
c1 += abs(weight*noise( uv ));
uv = m*uv + time;
weight *= 0.6;
}
c += c1;
float _clouds_amount = clamp( c, 0.0, 1.0 );
_clouds_amount *= clamp( abs( EYEDIR.y ) / clouds_blur, 0.0, 1.0 );
vec3 skycolour = COLOR;
vec3 clouds = mix(clouds_edge_color, clouds_main_color , pow( _clouds_amount,2.0) );
COLOR = mix( skycolour, clouds , _clouds_amount);
}
}i really like this shader from shadertoy> https://www.shadertoy.com/view/tdSXzD
i would like to add raymarching to the clouds in my current shader, also stars and the aurora borealis.
i dont need dynamic time of day or turbidity.
could someone help adding those to the current shader?
im also wondering if raymarching is too heavy for performance on modern machines or not.
if so, could it be faked somehow?
