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:


_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



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

let primitive = new Primitive({

geometryInstances: cylinderInstances,

appearance: app,

asynchronous: false



I think this might be this bug:

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?