Assimp access violation on existing aiVector3D - c++

Question

I'm using the following code to load in an .obj file using Assimp. Something goes wrong at the TextureCoordinates. The aiVector3D I try to access exists, but as soon as I store the values in a temp variable, it crashes my application.
Here's the code I use:
Assimp::Importer importer;
const aiScene* scene = importer.ReadFile(filename,
aiProcess_CalcTangentSpace |
aiProcess_Triangulate |
aiProcess_JoinIdenticalVertices |
aiProcess_SortByPType);
if (!scene)
{
printf("[ASSIMP] ");
printf(importer.GetErrorString());
printf("\n");
return nullptr;
}
Mesh* newMesh = new Mesh();
unsigned int vertexCount = scene->mMeshes[0]->mNumVertices;
unsigned int triangleCount = scene->mMeshes[0]->mNumFaces;
bool hasUv = scene->mMeshes[0]->HasTextureCoords(0);
newMesh->vertexCount = vertexCount;
newMesh->triangleCount = triangleCount;
newMesh->m_Vertices = new Vertex[vertexCount];
newMesh->m_Triangles = new Triangle[triangleCount];
for (unsigned int i = 0; i < vertexCount; i++) {
aiVector3D vertexPosition = scene->mMeshes[0]->mVertices[i];
aiVector3D vertexNormal = scene->mMeshes[0]->mNormals[i];
newMesh->m_Vertices[i].pos = glm::vec3(vertexPosition.x, vertexPosition.y, vertexPosition.z);
newMesh->m_Vertices[i].normal = glm::vec3(vertexNormal.x, vertexNormal.y, vertexNormal.z);
if (hasUv) {
aiVector3D uvCoordinates = scene->mMeshes[0]->mTextureCoords[i][0];
printf("uvCoordinates: %f %f %f\n", uvCoordinates.x, uvCoordinates.y, uvCoordinates.z);
newMesh->m_Vertices[i].u = uvCoordinates.x;
newMesh->m_Vertices[i].v = uvCoordinates.y;
}
}
for (unsigned int i = 0; i < triangleCount; i++) {
aiFace face = scene->mMeshes[0]->mFaces[i];
for (int j = 0; j < 3; j++) {
Triangle* tri = &newMesh->m_Triangles[i];
tri->vertex[j] = &newMesh->m_Vertices[face.mIndices[j]];
if (tri->vertex[0]->normal.y == 1.0f || tri->vertex[0]->normal.y == -1.0f) {
tri->color = glm::vec3(0.2f, 0.2f, 0.2f);
}
else
{
tri->color = glm::vec3(1.0f, 0.0f, 0.0f);
}
}
}
It crashes at the line printf("uvCoordinates: %f %f %f\n", uvCoordinates.x, uvCoordinates.y, uvCoordinates.z);, but if I remove this line, it crashes at newMesh->m_Vertices[i].u = uvCoordinates.x;. If I comment out the printf(), set both the u and v of the vertex to 0.0f and not use uvCoordinates at all, it still crashes on the newMesh->m_Vertices[i].u = uvCoordinates.x; line. If I leave the printf() uncommented, it prints the values of the uvCoordinates, but throws an access violation after.
I'm honestly out of ideas here. Here's a screenshot showing what I explained.

Answer 1

scene->mMeshes[0]->mTextureCoords[i][0]; is first texture coordinates for set i. What you wanted is to get first set of texture coordinates - so it should be scene->mMeshes[0]->mTextureCoords[0][i];