glutSolid* source code I am trying to build a dedocohedron in OpenGL, and I know that there is a built-in function in GLUT for the purpose. I was wondering if there is a way to either see the sourcecode for those functions, or to extract the generated data for vertices, colors, and indeces and print them?
The open source implementation FreeGLUT has these functions.
The geometry code can be found in freeglut/freeglut/src/fg_geometry.c.
For the dodecahedron, these are the values:
#define DODECAHEDRON_NUM_VERT           20
#define DODECAHEDRON_NUM_FACES          12
#define DODECAHEDRON_NUM_EDGE_PER_FACE  5
#define DODECAHEDRON_VERT_PER_OBJ       (DODECAHEDRON_NUM_FACES*DODECAHEDRON_NUM_EDGE_PER_FACE)
#define DODECAHEDRON_VERT_ELEM_PER_OBJ  (DODECAHEDRON_VERT_PER_OBJ*3)
#define DODECAHEDRON_VERT_PER_OBJ_TRI   (DODECAHEDRON_VERT_PER_OBJ+DODECAHEDRON_NUM_FACES*4)    /* 4 extra edges per face when drawing pentagons as triangles */
/* Vertex Coordinates */
static GLfloat dodecahedron_v[DODECAHEDRON_NUM_VERT*3] =
{
               0.0f,  1.61803398875f,  0.61803398875f,
    -          1.0f,            1.0f,            1.0f,
    -0.61803398875f,            0.0f,  1.61803398875f,
     0.61803398875f,            0.0f,  1.61803398875f,
               1.0f,            1.0f,            1.0f,
               0.0f,  1.61803398875f, -0.61803398875f,
               1.0f,            1.0f, -          1.0f,
     0.61803398875f,            0.0f, -1.61803398875f,
    -0.61803398875f,            0.0f, -1.61803398875f,
    -          1.0f,            1.0f, -          1.0f,
               0.0f, -1.61803398875f,  0.61803398875f,
               1.0f, -          1.0f,            1.0f,
    -          1.0f, -          1.0f,            1.0f,
               0.0f, -1.61803398875f, -0.61803398875f,
    -          1.0f, -          1.0f, -          1.0f,
               1.0f, -          1.0f, -          1.0f,
     1.61803398875f, -0.61803398875f,            0.0f,
     1.61803398875f,  0.61803398875f,            0.0f,
    -1.61803398875f,  0.61803398875f,            0.0f,
    -1.61803398875f, -0.61803398875f,            0.0f
};
/* Normal Vectors */
static GLfloat dodecahedron_n[DODECAHEDRON_NUM_FACES*3] =
{
                0.0f,  0.525731112119f,  0.850650808354f,
                0.0f,  0.525731112119f, -0.850650808354f,
                0.0f, -0.525731112119f,  0.850650808354f,
                0.0f, -0.525731112119f, -0.850650808354f,

     0.850650808354f,             0.0f,  0.525731112119f,
    -0.850650808354f,             0.0f,  0.525731112119f,
     0.850650808354f,             0.0f, -0.525731112119f,
    -0.850650808354f,             0.0f, -0.525731112119f,

     0.525731112119f,  0.850650808354f,             0.0f,
     0.525731112119f, -0.850650808354f,             0.0f,
    -0.525731112119f,  0.850650808354f,             0.0f, 
    -0.525731112119f, -0.850650808354f,             0.0f,
};

/* Vertex indices */
static GLubyte dodecahedron_vi[DODECAHEDRON_VERT_PER_OBJ] =
{
     0,  1,  2,  3,  4, 
     5,  6,  7,  8,  9, 
    10, 11,  3,  2, 12, 
    13, 14,  8,  7, 15, 

     3, 11, 16, 17,  4, 
     2,  1, 18, 19, 12, 
     7,  6, 17, 16, 15, 
     8, 14, 19, 18,  9, 

    17,  6,  5,  0,  4, 
    16, 11, 10, 13, 15, 
    18,  1,  0,  5,  9, 
    19, 14, 13, 10, 12
};

As for the second part of your question, tools such as renderdoc allow you to export meshes which are used in a render. To do this, you must first take a capture, find the corresponding draw call in event browser, open the Mesh Viewer and click on the export icon. You can do this with almost any mesh input to a vertex shader drawn in a supported API.