Files
TDT4230_final_project/src/utilities/modelLoader.cpp

204 lines
6.8 KiB
C++

#include "modelLoader.hpp"
#include <assimp/Importer.hpp> // C++ importer interface
#include <assimp/postprocess.h> // Post processing flags
#include <assimp/scene.h> // aiScene and aiNode
#include <assimp/material.h> // aiMaterial
#include <assimp/mesh.h> // aiMesh
#include <assimp/texture.h> // aiTexture
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <algorithm>
#include <assert.h>
#include "mesh.h"
#include "imageLoader.hpp"
typedef unsigned int uint;
using std::vector;
using std::map;
using std::cout;
using std::cerr;
using std::endl;
SceneNode* buildSceneNodes(
const aiNode* node,
const vector<Mesh>& meshes,
const vector<Material*>& mat_lookup) {
if (DEBUG) cout << "Building node from " << node->mName.data << "..." << endl;
// filter semantic-only nodes
if (node->mTransformation.IsIdentity()
&& node->mNumMeshes == 0
&& node->mNumChildren == 1)
return buildSceneNodes(node->mChildren[0], meshes, mat_lookup);
SceneNode* out = createSceneNode();
if (!node->mTransformation.IsIdentity()) {
aiQuaterniont<float> rotation;
aiVector3t<float> position, scaling;
node->mTransformation.Decompose(scaling, rotation, position);
for(uint i=0; i<3; i++) out->position[i] = position[i];
for(uint i=0; i<3; i++) out->scale[i] = scaling[i];
out->rotation = glm::eulerAngles(glm::quat(
rotation.w, rotation.x, rotation.y, rotation.z));
}
for (uint i = 0; i < node->mNumMeshes; i++) {
SceneNode* mesh_node = createSceneNode();
out->children.push_back(mesh_node);
uint meshidx = node->mMeshes[i];
mesh_node->setMaterial(*mat_lookup[meshidx]);
mesh_node->setMesh(&meshes[meshidx]);
}
for (uint i=0; i<node->mNumChildren; i++)
out->children.push_back(buildSceneNodes(node->mChildren[i], meshes, mat_lookup));
return out;
}
SceneNode* loadModelScene(const std::string& dirname, const std::string& filename, const map<int, Material>& overrides) {
Assimp::Importer importer;
const aiScene* scene = importer.ReadFile(dirname + "/" + filename,
aiProcess_CalcTangentSpace
//| aiProcess_FlipWindingOrder
| aiProcess_Triangulate
| aiProcess_GenNormals
| aiProcess_ImproveCacheLocality
//| aiProcess_JoinIdenticalVertices
| aiProcess_SortByPType
);
if (!scene) {
cerr << importer.GetErrorString() << endl;
throw 1;
}
// read materials
uint j=0;
Material default_material;
vector<Material> materials(scene->mNumMaterials);
for (Material& material : materials) {
const aiMaterial* aimat = scene->mMaterials[j++];
// print material
aiString name; aimat->Get(AI_MATKEY_NAME, name);
if (DEBUG){
cout << "Read material #" << j-1 << " '" << name.data << "':" << endl;
for (uint i=0; i < aimat->mNumProperties; i++)
cout << " " << aimat->mProperties[i]->mKey.data << endl;
}
aiColor3D color (1,1,1);
aiColor4D color4 (1,1,1,0);
if (AI_SUCCESS == aimat->Get(AI_MATKEY_COLOR_DIFFUSE, color))
material.diffuse_color = {color.r, color.g, color.b};
if (AI_SUCCESS == aimat->Get(AI_MATKEY_COLOR_EMISSIVE, color))
material.emissive_color = {color.r, color.g, color.b};
if (AI_SUCCESS == aimat->Get(AI_MATKEY_COLOR_SPECULAR, color))
material.specular_color = {color.r, color.g, color.b};
//if (AI_SUCCESS == aiGetMaterialColor(aimat, "$mat.gltf.pbrMetallicRoughness.baseColorFactor", 0, 0, &color4))
// material.diffuse_color = {color4.r, color4.g, color4.b};
//if (AI_SUCCESS == aiGetMaterialColor(aimat, "$mat.gltf.pbrMetallicRoughness.metallicFactor", 0, 0, &color4))
// material.emissive_color *= vec3{color4.r, color4.g, color4.b};
//if (AI_SUCCESS == aiGetMaterialColor(aimat, "$mat.gltf.pbrMetallicRoughness.roughnessFactor", 0, 0, &color4))
// material.specular_color = {color4.r, color4.g, color4.b};
aimat->Get(AI_MATKEY_SHININESS, material.shininess);
//todo: opacity?
if (aimat->GetTextureCount(aiTextureType_DIFFUSE)) {
aiString path; aimat->GetTexture(aiTextureType_DIFFUSE, 0, &path);
if (DEBUG) cout << " diffuse texture path: " << dirname << "/" << path.data << endl;
material.diffuse_texture = loadPNGFileDynamic(dirname + "/" + path.data);
}
if (aimat->GetTextureCount(aiTextureType_NORMALS)) {
aiString path; aimat->GetTexture(aiTextureType_NORMALS, 0, &path);
if (DEBUG) cout << " normal texture path: " << dirname << "/" << path.data << endl;
material.normal_texture = loadPNGFileDynamic(dirname + "/" + path.data);
}
if (aimat->GetTextureCount(aiTextureType_DISPLACEMENT)) {
aiString path; aimat->GetTexture(aiTextureType_DISPLACEMENT, 0, &path);
if (DEBUG) cout << " displacement texture path: " << dirname << "/" << path.data << endl;
material.displacement_texture = loadPNGFileDynamic(dirname + "/" + path.data);
}
if (aimat->GetTextureCount(aiTextureType_REFLECTION)) {
aiString path; aimat->GetTexture(aiTextureType_REFLECTION, 0, &path);
if (DEBUG) cout << " displacement texture path: " << dirname << "/" << path.data << endl;
material.reflection_texture = loadPNGFileDynamic(dirname + "/" + path.data);
}
}
// apply material overriders to material list
for (auto override : overrides) {
Material& mat = (override.first>=0)
? materials[override.first]
: default_material;
mat = mat.apply(override.second);
}
vector<Mesh> meshes( scene->mNumMeshes);
vector<Material*> mat_lookup(scene->mNumMeshes); // to be passed to buildSceneNodes
// read meshes
j=0;
for (Mesh& mesh : meshes) {
const aiMesh* aimesh = scene->mMeshes[j++];
for (uint i=0; i < aimesh->mNumVertices; i++){
mesh.vertices.push_back({
aimesh->mVertices[i].x,
aimesh->mVertices[i].y,
aimesh->mVertices[i].z,
});
mesh.normals.push_back({
aimesh->mNormals[i].x,
aimesh->mNormals[i].y,
aimesh->mNormals[i].z,
});
}
mat_lookup[j-1] = (aimesh->mMaterialIndex < meshes.size())
? &materials[aimesh->mMaterialIndex]
: &default_material;
if (aimesh->GetNumUVChannels() >= 1)
for (uint i=0; i < aimesh->mNumVertices; i++){
//assert(aimesh->mNumUVComponents[0] == 2);
mesh.textureCoordinates.push_back({
aimesh->mTextureCoords[0][i].x,
aimesh->mTextureCoords[0][i].y,
});
}
if (aimesh->GetNumColorChannels() >= 1)
for (uint i=0; i < aimesh->mNumVertices; i++){
mesh.colors.push_back({
aimesh->mColors[0][i].r,
aimesh->mColors[0][i].g,
aimesh->mColors[0][i].b,
aimesh->mColors[0][i].a,
});
}
for (uint i=0; i < aimesh->mNumFaces; i++){
assert(aimesh->mFaces[i].mNumIndices == 3);
mesh.indices.insert(mesh.indices.end(), {
aimesh->mFaces[i].mIndices[0],
aimesh->mFaces[i].mIndices[1],
aimesh->mFaces[i].mIndices[2],
});
}
}
// build scene node tree:
SceneNode* out = buildSceneNodes(scene->mRootNode, meshes, mat_lookup);
out->rotation.x += M_PI/2; // account for my weird coordinates. Z is upward damnit!
return out;
}