Assimp opengl load model vertices some values greater than 1 - c++

Question

I have the following code from learnopengl.com
void Model::load_model(string path)
{
//read file via ASSIMP
Assimp::Importer Importer;
const aiScene* scene = Importer.ReadFile(path, aiProcess_Triangulate | aiProcess_FlipUVs);
//check for errors
if(!scene || scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE || !scene->mRootNode)// if not zero
{
cout << "error, assimp ," << Importer.GetErrorString() << endl;
return;
}
//retrieve the directory path of the filepath
directory = path.substr(0, path.find_first_of('/'));
process_node(scene->mRootNode, scene);
}
/*
* Process a node in a recursive fashion . Process each individual mesh located at the node and repeat this process on its children nodes (if any)
*/
void Model::process_node(aiNode* node, const aiScene* scene)
{
for( GLuint i = 0; i < node->mNumMeshes; i++ )
{
//the node object only contains indices to index the actual objects of the scene.
//The scene contains all the data , node is just to keep stuff organized( like relations between nodes )
aiMesh* mesh = scene->mMeshes[node->mMeshes[i]];
meshes.push_back(process_mesh(mesh, scene));
}
//after we've processed all the meshes ( if any ) we then recusrsively process each of the children nodes
for(GLuint i = 0; i < node->mNumChildren; i++)
{
process_node(node->mChildren[i], scene);
}
}
Mesh Model::process_mesh(aiMesh* mesh, const aiScene* scene)
{
//data to fill
vector<Mesh::Vertex> vertices;
vector<GLuint> indices;
vector<Mesh::Texture> textures;
//walk through each of the meshes vertices
for(GLuint i = 0; i < mesh->mNumVertices; i++)
{
Mesh::Vertex vertex;
// we declare a placeholder vector since assimp uses its own vector class that doesn't directly convert to glm's vec3 class
//so we transfter the data to this placeholder glm::vec3 first
glm::vec3 vector;
//positions
vector.x = mesh->mVertices[i].x;
vector.y = mesh->mVertices[i].y;
vector.z = mesh->mVertices[i].z;
vertex.position = vector;
//normals
vector.x = mesh->mNormals[i].x;
vector.y = mesh->mNormals[i].y;
vector.z = mesh->mNormals[i].z; ...
When I print out the first 20 values of mesh->mVertices[i].x y and z I get some with values greater than 1 as show below
x1: 1.58967 Y1: -0.618526 z1: -0.683333
x1: 1.58939 Y1: -0.626895 z1: -0.681676
The obj file I am importing doesn't have any values greater than 1 and this is making the render fail. Where might the problem be?

Answer 1

The positions of a model are related to its model coordinate system. So they can get bigger and less than 1, -1 or whatever. OpenGL is not limited to the range of [0 ... 1] for any values. So when your renderer needs the range from 0 to 1 you need to:
Find the min and max for your coordinates
Rescale all coordinates:
float scale = 1.0/(max - min);
foreach ( v : mesh.Vertices)
v=v*scale;
Or rewrite your renderer that he is able to render arbitrary coorinate.