public void LoadMeshes(AssimpData a, int i)
        {
            assimp = a;
            index  = i;

            foreach (Mesh msh in assimp.scene.Meshes)
            {
                listView1.Items.Add(msh.Name);
            }
        }
        public void LoadMeshes(AssimpData a, int i)
        {
            assimp = a;
            index  = i;

            foreach (Mesh msh in assimp.scene.Meshes)
            {
                if (msh.MaterialIndex != -1 && assimp.scene.MaterialCount > msh.MaterialIndex)
                {
                    listView1.Items.Add($"{msh.Name}_{assimp.scene.Materials[msh.MaterialIndex].Name}");
                }
                else
                {
                    listView1.Items.Add(msh.Name);
                }
            }
        }