 1,
                        altitude: 100,
                    }, material, threeLayer)
                    return line;
                });
                var lines = list.slice(0, offset).map(d => {
                    return threeLayer.toLine(d.lineString, {}, lineMaterial);
                });


                console.log('lines.length:', lineTrails.length);
                console.timeEnd(timer);
                threeLayer.addMesh(lines);
                threeLayer.addMesh(lineTrails);
              