249 lines
9.7 KiB
C++
249 lines
9.7 KiB
C++
|
|
|
|
#ifndef MODEL_H
|
|
#define MODEL_H
|
|
|
|
#include "glad/glad.h"
|
|
|
|
#include <glm/glm.hpp>
|
|
#include <glm/gtc/matrix_transform.hpp>
|
|
#include <stb_image.h>
|
|
#include <assimp/Importer.hpp>
|
|
#include <assimp/scene.h>
|
|
#include <assimp/postprocess.h>
|
|
|
|
#include "mesh.h"
|
|
#include "shader.h"
|
|
|
|
#include <string>
|
|
#include <fstream>
|
|
#include <sstream>
|
|
#include <iostream>
|
|
#include <map>
|
|
#include <vector>
|
|
using namespace std;
|
|
|
|
unsigned int TextureFromFile(const char *path, const string &directory, bool gamma = false);
|
|
|
|
class Model
|
|
{
|
|
public:
|
|
// model data
|
|
vector<Texture> textures_loaded; // stores all the textures loaded so far, optimization to make sure textures aren't loaded more than once.
|
|
vector<Mesh> meshes;
|
|
string directory;
|
|
bool gammaCorrection;
|
|
|
|
// constructor, expects a filepath to a 3D model.
|
|
Model(string const &path, bool gamma = false) : gammaCorrection(gamma)
|
|
{
|
|
loadModel(path);
|
|
}
|
|
|
|
// draws the model, and thus all its meshes
|
|
void Draw(Shader &shader)
|
|
{
|
|
for(unsigned int i = 0; i < meshes.size(); i++)
|
|
meshes[i].Draw(shader);
|
|
}
|
|
|
|
private:
|
|
// loads a model with supported ASSIMP extensions from file and stores the resulting meshes in the meshes vector.
|
|
void loadModel(string const &path)
|
|
{
|
|
// read file via ASSIMP
|
|
Assimp::Importer importer;
|
|
const aiScene* scene = importer.ReadFile(path, aiProcess_Triangulate | aiProcess_GenSmoothNormals | aiProcess_FlipUVs | aiProcess_CalcTangentSpace);
|
|
// check for errors
|
|
if(!scene || scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE || !scene->mRootNode) // if is Not Zero
|
|
{
|
|
cout << "ERROR::ASSIMP:: " << importer.GetErrorString() << endl;
|
|
return;
|
|
}
|
|
// retrieve the directory path of the filepath
|
|
directory = path.substr(0, path.find_last_of('/'));
|
|
|
|
// process ASSIMP's root node recursively
|
|
processNode(scene->mRootNode, scene);
|
|
}
|
|
|
|
// processes a node in a recursive fashion. Processes each individual mesh located at the node and repeats this process on its children nodes (if any).
|
|
void processNode(aiNode *node, const aiScene *scene)
|
|
{
|
|
// process each mesh located at the current node
|
|
for(unsigned int i = 0; i < node->mNumMeshes; i++)
|
|
{
|
|
// the node object only contains indices to index the actual objects in the scene.
|
|
// the scene contains all the data, node is just to keep stuff organized (like relations between nodes).
|
|
aiMesh* mesh = scene->mMeshes[node->mMeshes[i]];
|
|
meshes.push_back(processMesh(mesh, scene));
|
|
}
|
|
// after we've processed all of the meshes (if any) we then recursively process each of the children nodes
|
|
for(unsigned int i = 0; i < node->mNumChildren; i++)
|
|
{
|
|
processNode(node->mChildren[i], scene);
|
|
}
|
|
|
|
}
|
|
|
|
Mesh processMesh(aiMesh *mesh, const aiScene *scene)
|
|
{
|
|
// data to fill
|
|
vector<Vertex> vertices;
|
|
vector<unsigned int> indices;
|
|
vector<Texture> textures;
|
|
|
|
// walk through each of the mesh's vertices
|
|
for(unsigned int i = 0; i < mesh->mNumVertices; i++)
|
|
{
|
|
Vertex vertex;
|
|
glm::vec3 vector; // we declare a placeholder vector since assimp uses its own vector class that doesn't directly convert to glm's vec3 class so we transfer the data to this placeholder glm::vec3 first.
|
|
// positions
|
|
vector.x = mesh->mVertices[i].x;
|
|
vector.y = mesh->mVertices[i].y;
|
|
vector.z = mesh->mVertices[i].z;
|
|
vertex.Position = vector;
|
|
// normals
|
|
if (mesh->HasNormals())
|
|
{
|
|
vector.x = mesh->mNormals[i].x;
|
|
vector.y = mesh->mNormals[i].y;
|
|
vector.z = mesh->mNormals[i].z;
|
|
vertex.Normal = vector;
|
|
}
|
|
// texture coordinates
|
|
if(mesh->mTextureCoords[0]) // does the mesh contain texture coordinates?
|
|
{
|
|
glm::vec2 vec;
|
|
// a vertex can contain up to 8 different texture coordinates. We thus make the assumption that we won't
|
|
// use models where a vertex can have multiple texture coordinates so we always take the first set (0).
|
|
vec.x = mesh->mTextureCoords[0][i].x;
|
|
vec.y = mesh->mTextureCoords[0][i].y;
|
|
vertex.TexCoords = vec;
|
|
// tangent
|
|
vector.x = mesh->mTangents[i].x;
|
|
vector.y = mesh->mTangents[i].y;
|
|
vector.z = mesh->mTangents[i].z;
|
|
vertex.Tangent = vector;
|
|
// bitangent
|
|
vector.x = mesh->mBitangents[i].x;
|
|
vector.y = mesh->mBitangents[i].y;
|
|
vector.z = mesh->mBitangents[i].z;
|
|
vertex.Bitangent = vector;
|
|
}
|
|
else
|
|
vertex.TexCoords = glm::vec2(0.0f, 0.0f);
|
|
|
|
vertices.push_back(vertex);
|
|
}
|
|
// now wak through each of the mesh's faces (a face is a mesh its triangle) and retrieve the corresponding vertex indices.
|
|
for(unsigned int i = 0; i < mesh->mNumFaces; i++)
|
|
{
|
|
aiFace face = mesh->mFaces[i];
|
|
// retrieve all indices of the face and store them in the indices vector
|
|
for(unsigned int j = 0; j < face.mNumIndices; j++)
|
|
indices.push_back(face.mIndices[j]);
|
|
}
|
|
// process materials
|
|
aiMaterial* material = scene->mMaterials[mesh->mMaterialIndex];
|
|
// we assume a convention for sampler names in the shaders. Each diffuse texture should be named
|
|
// as 'texture_diffuseN' where N is a sequential number ranging from 1 to MAX_SAMPLER_NUMBER.
|
|
// Same applies to other texture as the following list summarizes:
|
|
// diffuse: texture_diffuseN
|
|
// specular: texture_specularN
|
|
// normal: texture_normalN
|
|
|
|
// 1. diffuse maps
|
|
vector<Texture> diffuseMaps = loadMaterialTextures(material, aiTextureType_DIFFUSE, "texture_diffuse");
|
|
textures.insert(textures.end(), diffuseMaps.begin(), diffuseMaps.end());
|
|
// 2. specular maps
|
|
vector<Texture> specularMaps = loadMaterialTextures(material, aiTextureType_SPECULAR, "texture_specular");
|
|
textures.insert(textures.end(), specularMaps.begin(), specularMaps.end());
|
|
// 3. normal maps
|
|
std::vector<Texture> normalMaps = loadMaterialTextures(material, aiTextureType_HEIGHT, "texture_normal");
|
|
textures.insert(textures.end(), normalMaps.begin(), normalMaps.end());
|
|
// 4. height maps
|
|
std::vector<Texture> heightMaps = loadMaterialTextures(material, aiTextureType_AMBIENT, "texture_height");
|
|
textures.insert(textures.end(), heightMaps.begin(), heightMaps.end());
|
|
|
|
// return a mesh object created from the extracted mesh data
|
|
return Mesh(vertices, indices, textures);
|
|
}
|
|
|
|
// checks all material textures of a given type and loads the textures if they're not loaded yet.
|
|
// the required info is returned as a Texture struct.
|
|
vector<Texture> loadMaterialTextures(aiMaterial *mat, aiTextureType type, string typeName)
|
|
{
|
|
vector<Texture> textures;
|
|
for(unsigned int i = 0; i < mat->GetTextureCount(type); i++)
|
|
{
|
|
aiString str;
|
|
mat->GetTexture(type, i, &str);
|
|
// check if texture was loaded before and if so, continue to next iteration: skip loading a new texture
|
|
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; // a texture with the same filepath has already been loaded, continue to next one. (optimization)
|
|
break;
|
|
}
|
|
}
|
|
if(!skip)
|
|
{ // if texture hasn't been loaded already, load it
|
|
Texture 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); // store it as texture loaded for entire model, to ensure we won't unnecessary load duplicate textures.
|
|
}
|
|
}
|
|
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;
|
|
}
|
|
#endif
|
|
|