Make a Sphere

shape GenerateShape::makeSphere(shape sphere, GLuint recursions, float radius)
{

    if(sphere.numVerts == 0)//AKA the shape is empty
        sphere = makeTetrahedron(radius);// Make the base; a tetrahedron.

    if(!recursions) //If there are no recursions to make left.
        return sphere;

    std::vector<GLushort> newIndices;
    int i;
    for (i = 0; i < sphere.numIndices; i+=3)
    {
        vertex oldVert1 = sphere.vertices[sphere.indices[i]];
        vertex oldVert2 = sphere.vertices[sphere.indices[i+1]];
        vertex oldVert3 = sphere.vertices[sphere.indices[i+2]];
        vertex newVert;

        glm::vec3 newPosition; //The centroid
        newPosition.x = (oldVert1.position.x + oldVert2.position.x + oldVert3.position.x)/3;
        newPosition.y = (oldVert1.position.y + oldVert2.position.y + oldVert3.position.y)/3;
        newPosition.z = (oldVert1.position.z + oldVert2.position.z + oldVert3.position.z)/3;
        newPosition = glm::normalize(newPosition) * radius;
        newVert.position = newPosition;
        newVert.colour = glm::vec3(1, 1, 0); //Test colour

        sphere.vertices.push_back(newVert); //Add the vertex to the shapes list

        //Calculate the new vertex's index and add the indices for the three new triangles.
        GLuint newVertIndex = sphere.vertices.size()-1;
        printf("%d/n", newVertIndex);
        newIndices.push_back(i);
        newIndices.push_back(i+1);
        newIndices.push_back(newVertIndex);

        newIndices.push_back(i+1);
        newIndices.push_back(i+2);
        newIndices.push_back(newVertIndex);

        newIndices.push_back(i+2);
        newIndices.push_back(i);
        newIndices.push_back(newVertIndex);
    }

    //Set important data
    sphere.indices.resize(newIndices.size());
    sphere.indices.swap(newIndices);

    sphere.numVerts = sphere.vertices.size();
    sphere.numIndices = sphere.indices.size();

    return makeSphere(sphere, recursions-1, radius);
}