Create dome at end of Extruded geometry

Questions
1

HI,
Has any one any pointers on how to create a domed end to an extruded geometry. I have included a short video showing the effect on a Box geometry, but I need the box to be an extruded geometry.

Many Thanks

2

Maybe not good solution. Determinate vertices which needs to pull.

let vertice=mesh.geometry.attributes.positions.array;
let max=mesh.geometry.attributes.positions.array.length;
let center={x:0;y:0,z:0};
for(let n=0;n<max;n+=3){
let y=vertice[n+1]
if(vertice[n+1]>0){
if(center.y==0){ center.y=vertice[n+1]+0.2; }
let distance=Math.sqrt((center.x-vertice[n+0])**2+(center.y-vertice[n+1])**2+(center.z-vertice[n+2])**2);
vertice[n+1]+=distance/10;
}
}
mesh.geometry.attributes.positions.needsUpdate=true;
4

Hi @Picklehead …
I would do like this…

1 Like
5

Thanks for the suggestion :+1:

6

Thanks for the link, do you know if the SVG part is taken out of the equation will this work with just THREE.ExtrudeGeometry ?

I tried but ended up with two separate meshes, not sure if this is correct as not used CSG before

Screenshot 2025-05-31 003704
Screenshot 2025-05-31 0037041902Ă—901 13.1 KB

7

I will send a second example in which I then join the two parts… with CONTROL+U You can get the entire code
In the code sent previously, there is an intersection of the sphere and the extrusion… so I left the extrusion visible, that is, there are two meshes left.
In the new example I join the result of the intersection with the extrusion mesh to create a single final mesh.
You will see both results now… one with 2 meshes and one colored is only one mesh.
The CSG result is only one mesh… then You can add the result with other meshes…

PS: You can see that the meshc is similar to meshb, but in another position, prepared to be united with the result.

The next link:

And I decided to make one page more showing the three options of CSG… :wink:

2 Likes
8

@jrlazz that is brilliant, as I mentioned not used CSG before so very much appreciate the help!!

1 Like