3dobj-renderer/obj.cpp
2023-05-03 15:57:59 +05:00

95 lines
2.2 KiB
C++

#include "obj.h"
#include <fstream>
#include <vector>
#include <string>
#include <cstring>
#include <regex>
#include <iostream>
void ObjectLoader::load_mtl(string filename) {
string tmp;
ifstream f(filename);
int mtl_idx = -1;
while (getline(f, tmp)) {
if (tmp.rfind("newmtl", 0) == 0) {
mtl_idx += 1;
mtls.push_back(*(new Material));
mtls.back().name = tmp.substr(tmp.rfind(' ') + 1);
} else if (tmp[0] == 'K') {
float* target_list;
switch (tmp[1]) {
case 'a':
target_list = mtls.back().ambient;
break;
case 'd':
target_list = mtls.back().diffuse;
break;
case 's':
target_list = mtls.back().specular;
break;
default:
continue;
};
char delim = ' ';
char *token = strtok(const_cast<char*>(tmp.c_str()), &delim);
for (int i = 0; i < 3; i++) {
token = strtok(NULL, &delim);
target_list[i] = atof(token);
};
target_list[3] = 1.0f;
};
};
};
void ObjectLoader::load_obj(string filename) {
string tmp;
ifstream f(filename);
while (getline(f, tmp)) {
Material* mtl_ptr;
if (tmp[0] == 'v') {
float* target_list;
switch (tmp[1]) {
case ' ':
vertices.push_back(*(new Vertex));
target_list = vertices.back().pos;
break;
case 'n':
normals.push_back(*(new Normal));
target_list = normals.back().dir;
break;
default:
continue;
};
char delim = ' ';
char *token = strtok(const_cast<char*>(tmp.c_str()), &delim);
for (int i = 0; i < 3; i++) {
token = strtok(NULL, &delim);
target_list[i] = atof(token);
};
} else if (tmp.rfind("usemtl", 0) == 0) {
mtl_ptr = get_mtl_ptr(tmp.substr(tmp.find(' ') + 1));
} else if (tmp[0] == 'f') {
faces.push_back(*(new Face));
faces.back().mtl = mtl_ptr;
regex re("f (\\d*)//(\\d*) (\\d*)//(\\d*) (\\d*)//(\\d*)");
smatch match;
regex_search(tmp, match, re);
for (int i = 1; i < 7; i++) {
if (i % 2 == 0) {
faces.back().normals.push_back(&(normals[stoi(match.str(i)) - 1]));
} else {
faces.back().vertices.push_back(&(vertices[stoi(match.str(i)) - 1]));
};
};
};
};
};
Material* ObjectLoader::get_mtl_ptr(string mtl_name) {
for (int i = 0; i < mtls.size(); i++) {
if (mtls[i].name == mtl_name) {
return &(mtls[i]);
};
};
};