Rainier mood

https://www.shadertoy.com/view/ldfyzl

Shader code

shader_type canvas_item;

#define iResolution 1.0/SCREEN_PIXEL_SIZE
#define iTime TIME

uniform float size  = 5.;
uniform sampler2D iChannel0;
/*

A quick experiment with rain drop ripples.

This effect was written for and used in the launch scene of the
64kB intro "H - Immersion", by Ctrl-Alt-Test.

 > http://www.ctrl-alt-test.fr/productions/h-immersion/
 > https://www.youtube.com/watch?v=27PN1SsXbjM

-- 
Zavie / Ctrl-Alt-Test

*/

// Maximum number of cells a ripple can cross.
#define MAX_RADIUS 2

// Set to 1 to hash twice. Slower, but less patterns.
#define DOUBLE_HASH 0

// Hash functions shamefully stolen from:
// https://www.shadertoy.com/view/4djSRW
#define HASHSCALE1 .1031
#define HASHSCALE3 vec3(.1031, .1030, .0973)

float hash12(vec2 p)
{
	vec3 p3  = fract(vec3(p.xyx) * HASHSCALE1);
    p3 += dot(p3, p3.yzx + 19.19);
    return fract((p3.x + p3.y) * p3.z);
}

vec2 hash22(vec2 p)
{
	vec3 p3 = fract(vec3(p.xyx) * HASHSCALE3);
    p3 += dot(p3, p3.yzx+19.19);
    return fract((p3.xx+p3.yz)*p3.zy);

}

void fragment()
{
    float resolution = size;
	vec2 uv = SCREEN_UV * resolution;
	vec2 uv2 = uv * vec2(1.0 ,SCREEN_PIXEL_SIZE.x / SCREEN_PIXEL_SIZE.y);
    vec2 p0 = floor(uv2);

    vec2 circles = vec2(0.);
    for (int j = -MAX_RADIUS; j <= MAX_RADIUS; ++j)
    {
        for (int i = -MAX_RADIUS; i <= MAX_RADIUS; ++i)
        {
			vec2 pi = p0 + vec2(float(i), float(j));
            #if DOUBLE_HASH
            vec2 hsh = hash22(pi);
            #else
            vec2 hsh = pi;
            #endif
            vec2 p = pi + hash22(hsh);

            float t = fract(0.3*iTime + hash12(hsh));
            vec2 v = p - uv2;
            float d = length(v) - (float(MAX_RADIUS) + 1.)*t;

            float h = 1e-3;
            float d1 = d - h;
            float d2 = d + h;
            float p1 = sin(31.*d1) * smoothstep(-0.6, -0.3, d1) * smoothstep(0., -0.3, d1);
            float p2 = sin(31.*d2) * smoothstep(-0.6, -0.3, d2) * smoothstep(0., -0.3, d2);
            circles += 0.5 * normalize(v) * ((p2 - p1) / (2. * h) * (1. - t) * (1. - t));
        }
    }
    circles /= float((MAX_RADIUS*2+1)*(MAX_RADIUS*2+1));

    float intensity = mix(0.01, 0.15, smoothstep(0.1, 0.6, abs(fract(0.05*iTime + 0.5)*2.-1.)));
    vec3 n = vec3(circles, sqrt(1. - dot(circles, circles)));
    vec3 color = texture(iChannel0, uv/ resolution - intensity*n.xy).rgb + 5.*pow(clamp(dot(n, normalize(vec3(1., 0.7, 0.5))), 0., 1.), 6.);
	COLOR = vec4(color, 1.0);
}