Organizing the code for apartment modelling in C++ with OpenGl -

i making apartment c++ , opengl. have made basic walls, roof , floor declaring points in drawing function , of course works code messy , adding furniture way of course painful. asking how should organize objects , format drawing function?

here's current code:

// floor , roof of room 1 glbegin(gl_quads);     glnormal3f(0.0, 1.0, 0.0);     glcolor3f(0.0, 1.0, 1.0);     glvertex3f(0.0, 0.0, 0.0);     glvertex3f(1.0, 0.0, 0.0);     glvertex3f(1.0, 0.0, 1.0);     glvertex3f(0.0, 0.0, 1.0);      glnormal3f(0.0, -1.0, 0.0);     glcolor3f(0.0, 1.0, 0.0);     glvertex3f(0.0, 1.0, 0.0);     glvertex3f(1.0, 1.0, 0.0);     glvertex3f(1.0, 1.0, 1.0);     glvertex3f(0.0, 1.0, 1.0); glend();  // walls glbegin(gl_quad_strip);     glnormal3f(1.0, 0.0, 0.0);     glcolor3f(1.0, 1.0, 1.0);      glvertex3f(0.0, 0.0, 0.0);     glvertex3f(0.0, 1.0, 0.0);      glcolor3f(1.0, 0.0, 0.0);      glvertex3f(0.0,0.0,1.0);     glvertex3f(0.0,1.0,1.0);      glnormal3f(0.0, 0.0, -1.0);     glcolor3f(0.0, 0.0, 1.0);      glvertex3f(1.0, 0.0, 1.0);     glvertex3f(1.0, 1.0, 1.0);      glnormal3f(-1.0, 0.0, 0.0);     glcolor3f(0.5, 0.0, 0.5);      glvertex3f(1.0, 0.0, 0.0);     glvertex3f(1.0, 1.0, 0.0); glend();  , on room 2 , door spots.. 

any places read subject?

you can use 3d modelling software, e.g. →blender define geometry etc. recommend use →assimp load exported model. recommend avoid old fixed-function pipeline – write own little scenegraph engine , manage matrices , 3d math →glm