Usually, complex models like stadium are not drawn by code manually. Complex models are modelled and save to a file, using a 3D software like
Blender[
] or
Autodesk 3ds Max[
^]. And programmer will use a file parser to parse that file, in order to load the model into OpenGL. Common 3D file formats are
3ds[
](binary),
OBJ[
](text),
COLLADA[
](xml) and etc.