Downloaded area is slightly different from raw OSM data

[SherryGuo8023]

Figure 1 : Choose an area on OSM website and download it. Figure 2: Type in the same longitude and latitude in tangram and download it.

In figure 3, the white lines are generated roads meshes based on raw osm data by myself (same with figure 1). The colorful area is generated by tangram-unity plugin. Here you can see that, although they have the same range of lon and lat, the area is different. The world coordinates origin points are same(min lat and min lon of the input area).

Is this slight difference caused by different decimal point precision? How can I let them have same lat and lon?