Waves on waves

GLSL shader by scry · created 2026-02-05 · 10s loop · 2 passes

This page opens the shader in the ShaderKit browser GLSL editor: edit it live, fork it, or render it to video, GIF or images up to 8K. Also available as a full-screen view and an embeddable player.

Shader source (GLSL)

Common

#define pi acos(-1.)
#define deg pi/180.  //1 degree
#define time iTime*2.*pi/10. //sin(time) loops 10 seconds
#define R iResolution.xy //shorthand
#define ar R.x/R.y //aspect ratio
#define M iMouse //shorthand
#define xm (M.xy/R) //normalized mouse
#define nm ((xm.xy-0.5)*vec2(ar,1.)+0.5) //aspect ratio correction
vec3 cs = vec3(1.,2.,3.);
mat2 r2d(float a) {
    return mat2(cos(a),sin(a),-sin(a),cos(a));
}

// HSV to RGB
vec3 hsv2rgb(vec3 c) {
    vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
}

// RGB to HSV
vec3 rgb2hsv(vec3 c) {
    vec4 K = vec4(0.0, -1.0 / 3.0, 2.0 / 3.0, -1.0);
    vec4 p = mix(vec4(c.bg, K.wz), vec4(c.gb, K.xy), step(c.b, c.g));
    vec4 q = mix(vec4(p.xyw, c.r), vec4(c.r, p.yzx), step(p.x, c.r));
    float d = q.x - min(q.w, q.y);
    float e = 1.0e-10;
    return vec3(abs(q.z + (q.w - q.y) / (6.0 * d + e)), d / (q.x + e), q.x);
}

Buffer A (iChannel0)

void mainImage(out vec4 fragColor, in vec2 fragCoord) {
    vec2 uv = fragCoord.xy / iResolution.xy;
    
    // Initialize with random blobs on first frame or mouse click
    if (iFrame < 2 || iMouse.z > 0.5) {
        vec2 p = fragCoord / iResolution.y;
        float n = 0.0;
        for (int i = 0; i < 5; i++) {
            vec2 center = vec2(fract(sin(float(i) * 12.9898) * 43758.5453), 
                              fract(sin(float(i) * 78.233) * 43758.5453));
            n += exp(-length(p - center) * 8.0);
        }
        float val = clamp(n * 0.6, n*0.5, n*0.4);
        fragColor = vec4(val * fract(sin(float(1) * 11.1998) * 43758.5453),
                        val * fract(sin(float(1) * 12.9898) * 43758.5453),
                        val * fract(sin(float(1) * 1.5) * 43758.5453),
                        1.0);
        return;
    }
    
    // Lenia-style continuous cellular automata
    vec2 px = 1.0 / iResolution.xy;
    
    // Kernel radius and growth function parameters
    vec3 cell = texture(iChannel0, uv).rgb;
    float Rr = 19.0-sin(cell.b+cell.g+cell.r)*5.5;
    float mu = 0.31+cell.r*0.3;
    float sigma = 0.20-cell.g*0.20;
    
    // Compute weighted neighborhood sum with Gaussian kernel
    vec3 sum = vec3(0.0);
    vec3 totalWeight = vec3(0.0);
    
    
    for (float dy = -Rr; dy <= Rr; dy += 1.0) {
        for (float dx = -Rr; dx <= Rr; dx += 1.0) {
            float dist = length(vec2(dx, dy));
            if (dist > Rr) continue;
            
            // Ring kernel (shell-like)
            float kernelDist = abs(dist / Rr - 0.5) * 2.0;
            float weight = exp(-kernelDist * kernelDist / 0.15);
            
            vec3 neighbor = texture(iChannel0, uv + vec2(dx, dy) * px).rgb;
            
            // Red channel uses standard weight
            sum.r += neighbor.r * weight;
            totalWeight.r += weight;
            
            // Green and blue channels modulated by red
            float redModulation = cell.r;
            sum.g += neighbor.g * weight + neighbor.b * weight * redModulation * 0.1;
            sum.b += neighbor.b * weight + neighbor.g * weight * redModulation * 0.1;
            totalWeight.g += weight;
            totalWeight.b += weight;
        }
    }
    
    vec3 U = sum / totalWeight;
    
    // Red channel subtly influenced by blue and green
    float growthR = exp(-pow(U.r - mu, 2.0) / (2.0 * sigma * sigma)) * 2.0 - 1.0;
    growthR += (U.g + U.b - 2.0 * mu) * 0.02;
    
    vec3 growth = vec3(growthR, exp(-pow(U.g - mu, 2.0) / (2.0 * sigma * sigma)) * 2.0 - 1.0, exp(-pow(U.b - mu, 2.0) / (2.0 * sigma * sigma)) * 2.0 - 1.0);
    vec3 newState = clamp(cell + growth * 0.1, 0.0, 1.0);
    newState = mix(newState,texture(iChannel0,uv).rgb,0.2);
    fragColor = vec4(newState, 1.0);
}

Image

Not used

More shaders by scry

• Project_2026-08-15_18-22-06
• Project_2026-08-14_16-45-00
• Project_2026-07-24_15-10-23
• Project_2026-07-15_03-18-26
• Glass of Orange Juice (raymarched)
• Project_2026-07-13_00-53-50
• Project_2026-07-10_16-39-54
• Popcorn ceiling
• Project_2026-06-20_15-32-19
• Project_2026-06-25_12-22-43
• Visual Enhancer
• Project_2026-06-24_11-11-39

Browse all public shaders · All shaders by scry · ShaderKit home