Snowy mountain massif

const meta={name:'Winter mountainside / massif',role:'fill'};
const CFG={"id": "wmc-mountain-massif", "kind": "massif"};

function rng(s){return()=>{s^=s<<13;s^=s>>>17;s^=s<<5;return(s>>>0)/4294967296;};}
function bins(){return{rock:[],snow:[],wood:[],end:[],iron:[],grass:[]};}
function add(B,k,g,p=[0,0,0],rot=[0,0,0],sc=[1,1,1],tone=1){
 g=g.index?g.toNonIndexed():g.clone();const q=rot.isQuaternion?rot:new THREE.Quaternion().setFromEuler(new THREE.Euler(...rot));g.applyMatrix4(new THREE.Matrix4().compose(new THREE.Vector3(...p),q,new THREE.Vector3(...sc)));
 const ps=g.getAttribute('position'),ns=g.getAttribute('normal'),old=g.getAttribute('uv'),uv=[],c=[];
 for(let i=0;i<ps.count;i++){let x=ps.getX(i),y=ps.getY(i),z=ps.getZ(i),nx=Math.abs(ns.getX(i)),ny=Math.abs(ns.getY(i)),nz=Math.abs(ns.getZ(i));let u,v;if(k==='wood'){u=z*6+x*2;v=y*.7+x*.15;}else if(ny>nx&&ny>nz){u=x;v=z;}else if(nx>nz){u=z;v=y;}else{u=x;v=y;}let scale=k==='snow'?5:k==='rock'?1.8:k==='grass'?7:1;uv.push(u*scale,v*scale);c.push(Math.min(1,tone),Math.min(1,tone),Math.min(1,tone));}
 g.setAttribute('uv',new THREE.Float32BufferAttribute(uv,2));g.setAttribute('color',new THREE.Float32BufferAttribute(c,3));B[k].push(g);
}
function finish(root,B,M){for(const k of Object.keys(B)){if(!B[k].length)continue;const p=[],n=[],u=[],c=[];for(const g of B[k]){p.push(...g.attributes.position.array);n.push(...g.attributes.normal.array);u.push(...g.attributes.uv.array);c.push(...g.attributes.color.array);}const g=new THREE.BufferGeometry();for(const [key,a,s]of[['position',p,3],['normal',n,3],['uv',u,2],['color',c,3]])g.setAttribute(key,new THREE.Float32BufferAttribute(a,s));M[k].vertexColors=true;createPart(k,g,M[k],{parent:root});}}
function geo(p,ix){const g=new THREE.BufferGeometry();g.setAttribute('position',new THREE.Float32BufferAttribute(p,3));g.setIndex(ix);g.computeVertexNormals();return g;}
function grid(fn,n,m){const p=[],ix=[];for(let j=0;j<=m;j++)for(let i=0;i<=n;i++)p.push(...fn(i/n,j/m));for(let j=0;j<m;j++)for(let i=0;i<n;i++){let a=j*(n+1)+i,b=a+1,c=a+n+1,d=c+1;ix.push(a,c,b,b,c,d);}return geo(p,ix);}
function rod(B,k,a,b,r0,r1,n=7,tone=1){const va=new THREE.Vector3(...a),vb=new THREE.Vector3(...b),d=vb.clone().sub(va);add(B,k,new THREE.CylinderGeometry(r1,r0,d.length(),n,1),va.add(vb).multiplyScalar(.5).toArray(),new THREE.Quaternion().setFromUnitVectors(new THREE.Vector3(0,1,0),d.normalize()),[1,1,1],tone);}
function rock(B,p,s,seed,n=18,levels=5){const rr=rng(seed),rad=Array.from({length:n},(_,i)=>.89+.11*Math.sin(i*2.1+seed)+rr()*.09),vs=[],ix=[];for(let j=0;j<=levels;j++)for(let i=0;i<n;i++){const a=i/n*Math.PI*2,t=j/levels,fac=Math.sin(.15+t*2.85)**.30;vs.push(Math.cos(a)*s[0]*.5*rad[i]*fac+.06*s[0]*Math.sin(t*4+seed),s[1]*(t+.016*Math.sin(a*3+seed)*Math.sin(t*Math.PI)),Math.sin(a)*s[2]*.5*rad[i]*fac);}for(let j=0;j<levels;j++)for(let i=0;i<n;i++){let a=j*n+i,b=j*n+(i+1)%n,c=a+n,d=b+n;ix.push(a,c,b,b,c,d);}let bottom=vs.length/3;vs.push(0,0,0);let top=vs.length/3;vs.push(0,s[1],0);for(let i=0;i<n;i++){ix.push(bottom,i,(i+1)%n);ix.push(top,levels*n+(i+1)%n,levels*n+i);}let g=geo(vs,ix);g=g.toNonIndexed();g.computeVertexNormals();add(B,'rock',g,p,[0,0,0],[1,1,1],.89+(seed%6)*.026);}
function drift(B,p,s,seed,n=16,m=8){const g=grid((u,v)=>{const x=(u-.5)*2,z=(v-.5)*2,r=Math.max(Math.abs(x),Math.abs(z)),f=Math.max(0,1-r*r);return[x*s[0]/2*(.94+.06*Math.sin(v*11+seed)),s[1]*Math.pow(f,.65)*(1+.13*Math.sin(x*4+z*6+seed)+.07*Math.sin(x*15-z*11))+s[1]*-.08,z*s[2]/2*(.95+.05*Math.sin(u*13+seed))];},n,m);add(B,'snow',g,p);}
async function mats(){
 const rt=proceduralTexture({schemaVersion:2,size:512,name:'Schist fractured grain 560mm',layers:[{op:'noise',colorA:0x535d65,colorB:0x899196,scale:5,octaves:5,seed:329},{op:'noise',colorA:0x38434a,colorB:0xc5c5bd,scale:85,octaves:3,seed:551,opacity:.29,blend:'multiply'},{op:'stripes',colorA:0xa7aca7,colorB:0x757e81,count:66,angleDeg:18,opacity:.13,blend:'overlay'}]});
 const st=proceduralTexture({schemaVersion:2,size:256,name:'Dry settled snow fine aggregate 200mm',layers:[{op:'noise',colorA:0xdce4e9,colorB:0xf1f2ed,scale:57,octaves:3,seed:907}]});
 const wt=proceduralTexture({schemaVersion:2,size:256,name:'Weathered silver fir bark',layers:[{op:'noise',colorA:0x4d4943,colorB:0x81796b,scale:14,octaves:4,seed:53},{op:'stripes',colorA:0x403e39,colorB:0xa5a194,count:52,opacity:.32,blend:'multiply'}]});
 const et=proceduralTexture({schemaVersion:2,size:256,name:'Dry grey endgrain mottling',layers:[{op:'noise',colorA:0x8d8877,colorB:0xb2aa92,scale:50,octaves:4,seed:69}]});
 const rockM=pbrMaterial({albedo:await loadApprovedTexture('kiln.texture.rock-face-albedo.v1'),normal:await loadApprovedTexture('kiln.texture.rock-face-normal.v1'),roughness:.91,metalness:0});rockM.normalScale.set(.45,.45);rockM.color.set('#97c5ff');
 const snow=pbrMaterial({albedo:st,normal:normalMapFromHeight(st,{strength:.7}),roughness:.98,metalness:0});snow.normalScale.set(.27,.27);snow.side=THREE.DoubleSide;
 const wood=pbrMaterial({albedo:wt,normal:normalMapFromHeight(wt,{strength:2}),roughness:.96,metalness:0});wood.normalScale.set(.8,.8);
 return{vista:pbrMaterial({albedo:proceduralTexture({schemaVersion:2,size:128,name:'Distant weathered stone neutral modulation',layers:[{op:'noise',colorA:0xe2e4e5,colorB:0xffffff,scale:38,octaves:3,seed:48}]}),roughness:.96,metalness:0}),rock:rockM,snow,wood,end:pbrMaterial({albedo:et,roughness:.94,metalness:0}),iron:gameMaterial(0x363d3e,{roughness:.65,metalness:.65}),grass:gameMaterial(0x77766a,{roughness:1,flatShading:false})};
}
async function shelf(B){
 // Worn seating plane is deliberately level y=.48, 1.72 x .56 m clear.
 // The same long low schist extrusion can be embedded/scaled into an outcrop.
 const outline=[[-1.13,-.29],[-.96,-.43],[-.51,-.46],[.02,-.40],[.64,-.44],[1.11,-.32],[1.17,-.08],[1.09,.30],[.82,.42],[.31,.40],[-.30,.43],[-.98,.38],[-1.15,.18]];
 const vs=[],ix=[],N=outline.length,levels=[[0,.91,.02],[.13,1,0],[.21,.95,.025],[.36,1.01,0],[.455,.98,0],[.48,.93,0]];
 for(const [y,sc,shift]of levels)for(const [x,z]of outline)vs.push(x*sc+shift,y,z*sc);
 for(let j=0;j<levels.length-1;j++)for(let i=0;i<N;i++){let a=j*N+i,b=j*N+(i+1)%N,c=a+N,d=b+N;ix.push(a,c,b,b,c,d);}let ci=vs.length/3;vs.push(0,.48,0);for(let i=0;i<N;i++)ix.push(ci,(levels.length-1)*N+(i+1)%N,(levels.length-1)*N+i);ci=vs.length/3;vs.push(0,0,0);for(let i=0;i<N;i++)ix.push(ci,i,(i+1)%N);let g=geo(vs,ix).toNonIndexed();g.computeVertexNormals();add(B,'rock',g);
 // Fine broken bedding seams and attached chips remain below the sitting surface.
 for(let i=0;i<7;i++)rock(B,[-.91+i*.29,.045+(i%2)*.09,.315],[.40,.13,.20],51+i,9,2);
 drift(B,[.15,.476,-.36],[1.78,.085,.18],19,18,4);drift(B,[-1.03,.46,-.18],[.24,.06,.34],31,6,5);
}
async function boulder(B){rock(B,[-.04,-.06,.01],[1.72,1.05,1.25],84,18,5);rock(B,[.60,-.04,-.05],[.62,.45,.66],75,12,3);drift(B,[-.13,.92,-.08],[1.26,.18,.83],91,18,9);drift(B,[.57,.36,-.04],[.49,.07,.44],51,8,5);}
async function bank(B){drift(B,[0,0,0],[3.6,.57,1.55],71,26,12);rock(B,[-1.25,-.055,.36],[.49,.21,.30],16,9,2);rock(B,[.89,-.055,.50],[.32,.15,.27],19,8,2);}
async function clump(B){for(let i=0;i<9;i++){const a=i*2.399,r=.04+.018*(i%4),h=.17+.04*(i%5),x=Math.cos(a)*r,z=Math.sin(a)*r;const p=[x,0,z,x+.006,.01,z+.008,x+Math.cos(a)*.07,h*.62,z+Math.sin(a)*.07,x+Math.cos(a)*.075+.008,h*.65,z+Math.sin(a)*.075,x+Math.cos(a)*.13,h,z+Math.sin(a)*.13];add(B,'grass',geo(p,[0,2,1,1,2,3,2,4,3]));}rock(B,[.05,-.025,-.04],[.19,.08,.15],27,7,2);drift(B,[-.02,.008,-.02],[.28,.045,.20],17,5,3);}
async function log(B){
 const path=[[-1.65,.23,.05],[-.75,.26,-.04],[.15,.21,0],[1.53,.18,.05]],r=[.20,.23,.19,.14];for(let i=0;i<3;i++)rod(B,'wood',path[i],path[i+1],r[i],r[i+1],13,.89+i*.035);
 for(const [p,rad,rot]of[[path[0],.189,Math.PI/2],[path[3],.133,Math.PI/2]])add(B,'end',new THREE.CylinderGeometry(rad,rad,.006,17),p,[0,0,rot]);
 for(let i=0;i<5;i++){const x=-1.1+i*.47,z=i%2?.13:-.12;rod(B,'wood',[x,.25,z],[x+.18,.45+.05*(i%3),z*2.5],.045,.016,7);}
 // Supported drifts follow the actual log's upper arc, below crest by 20 mm.
 drift(B,[-.58,.425,-.02],[1.76,.10,.23],15,18,5);drift(B,[.79,.343,.03],[.90,.075,.19],27,12,4);
 for(let i=0;i<7;i++)rod(B,'wood',[-1.62,.13+i*.029,-.05],[-1.79+.03*(i%3),.15+i*.025,-.06],.013,.004,5,.91);
}
function mountain(B,ridge=false){
 const W=ridge?106:104,D=ridge?42:72,H=ridge?28:46,N=ridge?64:96,M=ridge?32:56;
 // Unequal serrated aretes with oblique daughter ridges, broad buttresses and
 // concave tributary gullies. Explicit crest graph replaces a fluted cone field.
 const crest=[[-.50,0,0],[-.40,.015,.26],[-.30,-.08,.56],[-.23,-.05,.72],[-.145,.04,.47],[-.045,-.015,.82],[-.01,-.045,.88],[.035,-.075,.84],[.11,-.01,.69],[.18,.085,.78],[.29,.05,.42],[.39,-.04,.31],[.50,0,0]];
 const arms=[
  [[-.30,-.08,.56],[-.36,-.24,.30],[-.44,-.43,.025]],
  [[-.23,-.05,.72],[-.20,.17,.44],[-.33,.37,.09],[-.38,.48,0]],
  [[-.045,-.015,.82],[-.13,-.18,.51],[-.08,-.35,.17],[-.13,-.49,0]],
  [[.035,-.075,.85],[.13,-.25,.43],[.27,-.42,.06]],
  [[.11,-.01,.64],[.02,.20,.39],[-.07,.40,.05]],
  [[.18,.085,.78],[.25,.26,.43],[.39,.44,.06]],
  [[.29,.05,.42],[.38,-.20,.24],[.48,-.37,.015]]
 ];
 const lines=[crest,...arms],segments=[];for(const line of lines)for(let j=1;j<line.length;j++)segments.push([line[j-1],line[j]]);
 function hash(x,z){let v=Math.sin(x*127.1+z*311.7)*43758.5453;return v-Math.floor(v);}
 function angular(x,z){const a=Math.floor(x),b=Math.floor(z),u=x-a,v=z-b;const q00=hash(a,b),q10=hash(a+1,b),q01=hash(a,b+1),q11=hash(a+1,b+1);return (u+v<1?q00+(q10-q00)*u+(q01-q00)*v:q11+(q01-q11)*(1-u)+(q10-q11)*(1-v))-.5;}
 function height(x,z,detailEnabled=true){
  let h=0;
  for(let k=0;k<segments.length;k++){
   const [a,b]=segments[k],dx=(b[0]-a[0])*W,dz=(b[1]-a[1])*D,px=(x-a[0])*W,pz=(z-a[1])*D;
   const t=Math.max(0,Math.min(1,(px*dx+pz*dz)/(dx*dx+dz*dz))),cross=px*dz-pz*dx;
   const dist=Math.hypot(px-t*dx,pz-t*dz),level=(a[2]*(1-t)+b[2]*t)*H;
   const slope=(cross<0?1.46:1.04)*(ridge?.78:1)*(1+.13*Math.sin(k*4.2));
   h=Math.max(h,level-slope*dist-.018*dist*dist);
  }
  const edge=Math.max(0,Math.min(1,(.5-Math.abs(x))*22,(.5-Math.abs(z))*18));
  const detail=(angular(x*29,z*23)*1.8+angular(x*67+7,z*59)*.60)*Math.min(1,h/9);
  const band=(h+x*W*.18+z*D*.12)/7.3,fracture=(band-Math.floor(band)-.5)*2.5*Math.min(1,h/14);
  return Math.max(0,h+(detailEnabled?detail+fracture:0))*edge;
 }
 const g=grid((u,v)=>{const x=u-.5,z=v-.5;return[x*W,height(x,z),z*D];},N,M);
 const pp=g.attributes.position,nn=g.attributes.normal,c=[],uv=[];
 for(let i=0;i<pp.count;i++){
  const x=pp.getX(i),y=pp.getY(i),z=pp.getZ(i),h=height(x/W,z/D,false);
  const basin=height((x+4)/W,z/D,false)+height((x-4)/W,z/D,false)+height(x/W,(z+4)/D,false)+height(x/W,(z-4)/D,false)-4*h;
  const variation=angular(x*.11,z*.11)*.12;
  let s=Math.max(0,Math.min(1,(nn.getY(i)-.55)*3.1+basin*.21+variation+.16));
  s=s*s*(3-2*s);if(ridge)s*=.82;
  const tone=.93+angular(x*.21+y*.14,z*.18)*.10,rock=new THREE.Color(ridge?0x536472:0x596875).multiplyScalar(tone),snow=new THREE.Color(0xe7edf0),col=rock.lerp(snow,s);
  c.push(col.r,col.g,col.b);uv.push(x*.09,z*.09);
 }
 g.setAttribute('color',new THREE.Float32BufferAttribute(c,3));g.setAttribute('uv',new THREE.Float32BufferAttribute(uv,2));
 const tri=g.toNonIndexed(),rockP=[],rockN=[],rockU=[],snowP=[],snowN=[],snowU=[];
 const pos=tri.attributes.position,norm=tri.attributes.normal,col=tri.attributes.color;
 // Clip each face at an interpolated snow-retention contour. Whole-face
 // classification made regular saw teeth and isolated triangular snow flakes.
 const threshold=.43;
 function clip(poly,positive){const out=[];for(let j=0;j<poly.length;j++){const a=poly[j],b=poly[(j+1)%poly.length],ai=positive?a[6]>=threshold:a[6]<=threshold,bi=positive?b[6]>=threshold:b[6]<=threshold;if(ai)out.push(a);if(ai!==bi){const t=(threshold-a[6])/(b[6]-a[6]);out.push(a.map((v,k)=>v+(b[k]-v)*t));}}return out;}
 for(let i=0;i<pos.count;i+=3){
  const verts=[];for(let j=0;j<3;j++){const k=i+j;verts.push([pos.getX(k),pos.getY(k),pos.getZ(k),norm.getX(k),norm.getY(k),norm.getZ(k),col.getX(k)]);}
  const nx=Math.abs(verts[0][3]+verts[1][3]+verts[2][3]),ny=Math.abs(verts[0][4]+verts[1][4]+verts[2][4]),nz=Math.abs(verts[0][5]+verts[1][5]+verts[2][5]);
  for(const isSnow of [false,true]){const poly=clip(verts,isSnow),ps=isSnow?snowP:rockP,ns=isSnow?snowN:rockN,us=isSnow?snowU:rockU;for(let j=1;j<poly.length-1;j++)for(const a of [poly[0],poly[j],poly[j+1]]){const [x,y,z,ax,ay,az]=a,len=Math.hypot(ax,ay,az),scale=isSnow?.7:.14;ps.push(x,y,z);ns.push(ax/len,ay/len,az/len);us.push((ny>nx&&ny>nz?x:nx>nz?z:x)*scale,(ny>nx&&ny>nz?z:y)*scale);}}
 }
 for(const [key,p,n,u]of[['rock',rockP,rockN,rockU],['snow',snowP,snowN,snowU]]){const t=new THREE.BufferGeometry();t.setAttribute('position',new THREE.Float32BufferAttribute(p,3));t.setAttribute('normal',new THREE.Float32BufferAttribute(n,3));t.setAttribute('uv',new THREE.Float32BufferAttribute(u,2));t.setAttribute('color',new THREE.Float32BufferAttribute(p.map(()=>1),3));B[key].push(t);}
}
async function marker(B){
 add(B,'wood',await roundedBoxGeo(.14,.85,.14,.004,{style:'chamfer'}),[0,.425,0]);
 add(B,'wood',await roundedBoxGeo(.34,.10,.17,.005,{style:'chamfer'}),[0,.80,0]);
 // Recessed dark iron arrow in the cap, legible without loud labels.
 const sh=new THREE.Shape();for(const [i,p]of [[-.11,-.012],[.035,-.012],[.035,-.032],[.108,0],[.035,.032],[.035,.012],[-.11,.012]].entries())i?sh.lineTo(...p):sh.moveTo(...p);sh.closePath();add(B,'iron',new THREE.ShapeGeometry(sh),[0,.80,.086]);
 drift(B,[0,.852,0],[.36,.044,.19],47,7,3);
}
const BUILD={shelf,boulder,bank,clump,log,massif:B=>mountain(B,false),ridge:B=>mountain(B,true),marker};
async function build(){const root=createRoot(CFG.id),B=bins();await BUILD[CFG.kind](B);finish(root,B,await mats());return root;}