the primitive objects that i create by geometry data(pos,uv...)is out of shape on iphone

the primitive objects that i create by geometry data(pos,uv…)is out of shape on iphone,but be normal in other platform;

the Adress: https://trinasolartest_v2.boonray.com/#/?id=290

maincode:

_createGeometry(positions, sts, indices)

{

return new Geometry({

attributes: {

position: new GeometryAttribute({

componentDatatype: ComponentDatatype.DOUBLE,

componentsPerAttribute: 3,

values: positions

}),

st: new GeometryAttribute({

componentDatatype: ComponentDatatype.FLOAT,

componentsPerAttribute: 2,

values: sts

})

},

indices: indices,

primitiveType: PrimitiveType.TRIANGLES,

boundingSphere: BoundingSphere.fromVertices(positions)

});

}

//-------------add group instance(same geometry different modelMatrix ) to a Instance Array;

mat = Matrix4.multiply(this.instances[i].modelMatrix, mat, mat);

let instance = new GeometryInstance({

geometry: cylinder,

modelMatrix: mat

});

cylinderInstances.push(instance);

//------------------------geometryInstances —>to a new primitive

let primitive = new Primitive({

geometryInstances: cylinderInstances,

appearance: app,

asynchronous: false

})

this.viewer.scene.primitives.add(primitive);

I think this might be this bug:

https://github.com/AnalyticalGraphicsInc/cesium/issues/7100

Can you confirm that you see the red box distorted in the same way on your iPhone? If so, can you post what version of iOS and browser you’re using?