Mountain without noise function

float mountain(vec3 x)
{
    vec2 p = x.xz * 0.05;
    float t = 0.0, a = 1.0;
    float dist = smoothstep(0.9, 1.0, 1.0-(length(p)-0.1));
    for (int i=0; i<3; i++){
        float n = (textureLod(iChannel0, p, 0.0).r);
        t += mix(n, dist+n, dist) * a;
        p = mat2(0.8,-0.6,0.6,0.8)*p*2.0+dist*0.3;
        a *= 0.5;
    }
    return max(length(x)-5.0, x.y-t);
}
//link to texture: https://cdn.discordapp.com/attachments/658085531397128207/808748224227573850/8979352a182bde7c3c651ba2b2f4e0615de819585cc37b7175bcefbca15a6683.png