"Hello, is there a method in iTwin.js for directly transforming a model into the current world coordinates?"

[MYDJH]

"I read the geometric information of this object using the following code."

 const it = new GeometryStreamIterator(props.geom);
        for (const entry of it) {
          console.log(
            entry.primitive.geometry,
            index,
            "entry"
          );
Let curve =  entry.primitive.geometry
}
//Add the model to the view.
      decoratorState.setLinePixels(LinePixels.Solid);
     decoratorState.addGeometry(curve);

"However, when I add this entry.primitive.geometry to the model, I find that the position of the added model does not match the position of the original model."

"The position of the added model and the actual position of the model."

the geometric information read from entry.primitive.geometry

"I found that the actual position of the model needs to be adjusted by adding the element's origin to get the correct position. Now, I want to directly modify the position of the entry.primitive.geometry object. Does iTwin.js provide such a coordinate transformation?"

the element's origin:

"The actual model coordinates need to be adjusted by adding x + element.origin.x, y + element.origin.y, and z + element.origin.z. How can I solve this problem? Thank you very much for reading, and I would greatly appreciate any good suggestions you may have."

[bbastings]

The geometry stream entries are stored relative to the element's placement. The easiest way to iterate over the geometry in world coordinates is to create the iterator from a GeometricElementProps. World Coordinate Iterator from GeometricElement3d

Similarly, if you were to create a new element, it's geometry should also be stored relative to a meaningful placement and not world coordinates. GeometryStreamBuilder can automatically transform world coordinate geometry relative to the desired placement using one of the method to specify the local-to-world transform such as. If you were creating a new element from the geometry extracted from an existing element, it might make sense to create the new element using the same placement as the existing element, etc. You aren't though, looks like you are just creating a view decorations.

More information about creating geometric element's and placement here.

[MYDJH]

Thank you very much.