Dicewars-Siedler/src/engine/renderer/loader/OBJLoader.cpp
2026-02-13 23:09:59 +01:00

91 lines
3.2 KiB
C++

//
// Created by sebastian on 07.02.26.
//
#include "OBJLoader.h"
#define TINYOBJLOADER_IMPLEMENTATION
#include <complex>
#include <filesystem>
#include <iostream>
#include "tiny_obj_loader.h"
std::shared_ptr<TexturedModel> OBJLoader::loadModel(const std::string &modelPath, const std::string& texturePath, Loader &loader) {
tinyobj::attrib_t attrib;
std::vector<tinyobj::shape_t> shapes;
std::vector<tinyobj::material_t> materials;
std::string warn, err;
std::string baseDir = std::filesystem::path(modelPath).parent_path().string();
bool ret = tinyobj::LoadObj(&attrib, &shapes, &materials, &warn, &err, modelPath.c_str(), baseDir.c_str());
if (!warn.empty()) {
std::cout << "OBJ Loader warning: " << warn << std::endl;
}
if (!err.empty()) {
std::cerr << "OBJ Loader error: " << err << std::endl;
}
if (!ret) {
throw std::runtime_error("Failed to load OBJ");
}
std::vector<SubModel> subModels;
for (const auto& shape : shapes) {
std::vector<float> vertices;
std::vector<float> normals;
std::vector<float> uvs;
std::vector<int> indices;
int indexOffset = 0;
for (const auto& index : shape.mesh.indices) {
// Vertex-Position
vertices.push_back(attrib.vertices[3*index.vertex_index + 0]);
vertices.push_back(attrib.vertices[3*index.vertex_index + 1]);
vertices.push_back(attrib.vertices[3*index.vertex_index + 2]);
// UV-Koordinaten
if (!attrib.texcoords.empty()) {
uvs.push_back(attrib.texcoords[2*index.texcoord_index + 0]);
uvs.push_back(1.0f - attrib.texcoords[2*index.texcoord_index + 1]);
} else {
uvs.push_back(0.0f);
uvs.push_back(0.0f);
}
normals.push_back(attrib.normals[3*index.normal_index + 0]);
normals.push_back(attrib.normals[3*index.normal_index + 1]);
normals.push_back(attrib.normals[3*index.normal_index + 2]);
// Index
indices.push_back(indexOffset);
indexOffset++;
}
RawModel rawModel = loader.loadToVAO(vertices, normals, uvs, indices);
std::shared_ptr<ModelTexture> texture = nullptr;
if (!materials.empty() && !shape.mesh.material_ids.empty()) {
int matID = shape.mesh.material_ids[0];
if (matID >= 0 && matID < static_cast<int>(materials.size())) {
tinyobj::material_t &mat = materials[matID];
if (!mat.diffuse_texname.empty()) {
std::string texFile = mat.diffuse_texname;
std::filesystem::path fullTexPath = std::filesystem::path(baseDir) / std::filesystem::path(texFile);
texture = std::make_shared<ModelTexture>(loader.loadTextureFromFile(fullTexPath.string()));
}
}
}
if (!texture) {
texture = std::make_shared<ModelTexture>(loader.loadTextureFromFile(texturePath));
}
subModels.emplace_back(
std::make_shared<RawModel>(rawModel), texture
);
}
return std::make_shared<TexturedModel>(subModels);
}