OpenGL-ImportModel.zip

#include "Model.h" #include <stb/stb_image.h> using namespace std; void Model::Draw(Shader shader) { for (unsigned int i = 0; i < meshes.size(); i++) meshes[i].Draw(shader); } void Model::loadModel(string const &path) { Assimp::Importer importer; const aiScene* scene = importer.ReadFile(path, aiProcess_Triangulate | aiProcess_FlipUVs | aiProcess_CalcTangentSpace); if (!scene || scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE || !scene->mRootNode) // if is Not Zero { cout << "ERROR::ASSIMP:: " << importer.GetErrorString() << endl; return; } directory = path.substr(0, path.find_last_of('/')); processNode(scene->mRootNode, scene); } void Model::processNode(aiNode *node, const aiScene *scene) { for (unsigned int i = 0; i < node->mNumMeshes; i++) { aiMesh* mesh = scene->mMeshes[node->mMeshes[i]]; meshes.push_back(processMesh(mesh, scene)); } for (unsigned int i = 0; i < node->mNumChildren; i++) { processNode(node->mChildren[i], scene); } } Mesh Model::processMesh(aiMesh *mesh, const aiScene *scene) { vector<Vertex> vertices; vector<unsigned int> indices; vector<MeshTexture> textures; //顶点&&索引 for (unsigned int i = 0; i < mesh->mNumVertices; i++) { Vertex vertex; glm::vec3 vector; vector.x = mesh->mVertices[i].x; vector.y = mesh->mVertices[i].y; vector.z = mesh->mVertices[i].z; vertex.Position = vector; vector.x = mesh->mNormals[i].x; vector.y = mesh->mNormals[i].y; vector.z = mesh->mNormals[i].z; vertex.Normal = vector; if (mesh->mTextureCoords[0]) { glm::vec2 vec; vec.x = mesh->mTextureCoords[0][i].x; vec.y = mesh->mTextureCoords[0][i].y; vertex.TexCoords = vec; } else vertex.TexCoords = glm::vec2(0.0f, 0.0f); vector.x = mesh->mTangents[i].x; vector.y = mesh->mTangents[i].y; vector.z = mesh->mTangents[i].z; vertex.Tangent = vector; vector.x = mesh->mBitangents[i].x; vector.y = mesh->mBitangents[i].y; vector.z = mesh->mBitangents[i].z; vertex.Bitangent = vector; vertices.push_back(vertex); } for (unsigned int i = 0; i < mesh->mNumFaces; i++) { aiFace face = mesh->mFaces[i]; for (unsigned int j = 0; j < face.mNumIndices; j++) indices.push_back(face.mIndices[j]); } //材质 aiMaterial* material = scene->mMaterials[mesh->mMaterialIndex]; vector<MeshTexture> diffuseMaps = loadMaterialTextures(material, aiTextureType_DIFFUSE, "texture_diffuse"); textures.insert(textures.end(), diffuseMaps.begin(), diffuseMaps.end()); vector<MeshTexture> specularMaps = loadMaterialTextures(material, aiTextureType_SPECULAR, "texture_specular"); textures.insert(textures.end(), specularMaps.begin(), specularMaps.end()); std::vector<MeshTexture> normalMaps = loadMaterialTextures(material, aiTextureType_HEIGHT, "texture_normal"); textures.insert(textures.end(), normalMaps.begin(), normalMaps.end()); std::vector<MeshTexture> heightMaps = loadMaterialTextures(material, aiTextureType_AMBIENT, "texture_height"); textures.insert(textures.end(), heightMaps.begin(), heightMaps.end()); return Mesh(vertices, indices, textures); } std::vector<MeshTexture> Model::loadMaterialTextures(aiMaterial *mat, aiTextureType type, string typeName) { vector<MeshTexture> textures; for (unsigned int i = 0; i < mat->GetTextureCount(type); i++) { aiString str; mat->GetTexture(type, i, &str); bool skip = false; for (unsigned int j = 0; j < textures_loaded.size(); j++) { if (std::strcmp(textures_loaded[j].path.data(), str.C_Str()) == 0) { textures.push_back(textures_loaded[j]); skip = true; break; } } //优化方案：如果纹理还没有被加载，则加载它 if (!skip) { MeshTexture texture; texture.id = TextureFromFile(str.C_Str(), this->directory); texture.type = typeName; texture.path = str.C_Str(); textures.push_back(texture); textures_loaded.push_back(texture); } } return textures; } unsigned int TextureFromFile(const char *path, const string &directory, bool gamma) { string filename = string(path); filename = directory + '/' + filename; unsigned int textureID; glGenTextures(1, &textureID); int width, height, nrComponents; unsigned char *data = stbi_load(filename.c_str(), &width, &height, &nrComponents, 0); if (data) { GLenum format; if (nrComponents == 1) format = GL_RED; else if (nrComponents == 3) format = GL_RGB; else if (nrComponents == 4) format = GL_RGBA; glBindTexture(GL_TEXTURE_2D, textureID); glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data); glGenerateMipmap(GL_TEXTURE_2D); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); stbi_image_free(data); } else { std::cout << "Texture failed to load at path: " << path << std::endl; stbi_image_free(data); } return textureID; }