SupaLidlGame/Shaders/Godrays.gdshader

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/*
Shader from Godot Shaders - the free shader library.
godotshaders.com/shader/god-rays
Feel free to use, improve and change this shader according to your needs
and consider sharing the modified result on godotshaders.com.
*/
shader_type canvas_item;
uniform sampler2D SCREEN_TEXTURE : hint_screen_texture, filter_linear_mipmap;
uniform float angle : hint_range(-5, 5) = -0.3;
uniform float position = -0.2;
uniform float spread : hint_range(0.0, 1.0) = 0.5;
uniform float cutoff : hint_range(-1.0, 1.0) = 0.1;
uniform float falloff : hint_range(0.0, 2.0) = 0.2;
uniform float edge_fade : hint_range(0.0, 1.0) = 0.15;
uniform float speed = 1.0;
uniform float ray1_density = 8.0;
uniform float ray2_density = 30.0;
uniform float ray2_intensity : hint_range(0.0, 1.0) = 0.3;
uniform vec4 color : source_color = vec4(1.0, 0.9, 0.65, 0.8);
uniform bool hdr = false;
uniform float seed = 5.0;
// Random and noise functions from Book of Shader's chapter on Noise.
float random(vec2 _uv) {
_uv += min(TIME,0.0);
return fract(sin(dot(_uv.xy,
vec2(12.9898, 78.233))) *
43758.5453123);
}
float noise (in vec2 uv) {
vec2 i = floor(uv);
vec2 f = fract(uv);
// Four corners in 2D of a tile
float a = random(i);
float b = random(i + vec2(1.0, 0.0));
float c = random(i + vec2(0.0, 1.0));
float d = random(i + vec2(1.0, 1.0));
// Smooth Interpolation
// Cubic Hermine Curve. Same as SmoothStep()
vec2 u = f * f * (3.0-2.0 * f);
// Mix 4 coorners percentages
return mix(a, b, u.x) +
(c - a)* u.y * (1.0 - u.x) +
(d - b) * u.x * u.y;
}
mat2 rotate(float _angle){
return mat2(vec2(cos(_angle), -sin(_angle)),
vec2(sin(_angle), cos(_angle)));
}
vec4 screen(vec4 base, vec4 blend){
return 1.0 - (1.0 - base) * (1.0 - blend);
}
float custom_smooth_step(float limit1, float limit2, float x) {
if (x <= limit1) {
return 0.0;
} else if (x >= limit2) {
return 1.0;
}
return (limit1 + x) / (limit1 + limit2);
}
void fragment()
{
// Rotate, skew and move the UVs
vec2 transformed_uv = ( rotate(angle) * (UV - position) ) / ( (UV.y + spread) - (UV.y * spread) );
// Animate the ray according the the new transformed UVs
vec2 ray1 = vec2(transformed_uv.x * ray1_density + sin(TIME * 0.1 * speed) * (ray1_density * 0.2) + seed, 1.0);
vec2 ray2 = vec2(transformed_uv.x * ray2_density + sin(TIME * 0.2 * speed) * (ray1_density * 0.2) + seed, 1.0);
// Cut off the ray's edges
float cut = step(cutoff, transformed_uv.x) * step(cutoff, 1.0 - transformed_uv.x);
ray1 *= cut;
ray2 *= cut;
// Apply the noise pattern (i.e. create the rays)
float rays;
if (hdr){
// This is not really HDR, but check this to not clamp the two merged rays making
// their values go over 1.0. Can make for some nice effect
rays = noise(ray1) + (noise(ray2) * ray2_intensity);
}
else{
rays = clamp(noise(ray1) + (noise(ray2) * ray2_intensity), 0., 1.);
}
// Fade out edges
rays *= custom_smooth_step(0.0, falloff, (1.0 - UV.y)); // Bottom
rays *= smoothstep(0.0 + cutoff, edge_fade + cutoff, transformed_uv.x); // Left
rays *= smoothstep(0.0 + cutoff, edge_fade + cutoff, 1.0 - transformed_uv.x); // Right
// Color to the rays
vec3 shine = vec3(rays) * color.rgb;
// Try different blending modes for a nicer effect. "Screen" is included in the code,
// but take a look at https://godotshaders.com/snippet/blending-modes/ for more.
// With "Screen" blend mode:
shine = screen(texture(SCREEN_TEXTURE, SCREEN_UV), vec4(color)).rgb;
COLOR = vec4(shine, rays * color.a);
}