extern float time;

vec4 effect(vec4 color, Image tex, vec2 uv, vec2 sc) {
float d = sin(uv.x * 20.0 + time * 3.0) * 0.02 +
cos(uv.y * 15.0 + time * 2.5) * 0.02;
return Texel(tex, uv + d);
}