diff options
Diffstat (limited to 'extern/quadriflow/src/loader.cpp')
| -rw-r--r-- | extern/quadriflow/src/loader.cpp | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/extern/quadriflow/src/loader.cpp b/extern/quadriflow/src/loader.cpp new file mode 100644 index 00000000000..aa27066e6e4 --- /dev/null +++ b/extern/quadriflow/src/loader.cpp @@ -0,0 +1,159 @@ +// +// loader.cpp +// Loop +// +// Created by Jingwei on 10/22/17. +// Copyright © 2017 Jingwei. All rights reserved. +// + +#include "loader.hpp" + +#include <fstream> +#include <unordered_map> + +namespace qflow { + +inline std::vector<std::string> &str_tokenize(const std::string &s, char delim, std::vector<std::string> &elems, bool include_empty = false) { + std::stringstream ss(s); + std::string item; + while (std::getline(ss, item, delim)) + if (!item.empty() || include_empty) + elems.push_back(item); + return elems; +} + +inline std::vector<std::string> str_tokenize(const std::string &s, char delim, bool include_empty) { + std::vector<std::string> elems; + str_tokenize(s, delim, elems, include_empty); + return elems; +} + +inline uint32_t str_to_uint32_t(const std::string &str) { + char *end_ptr = nullptr; + uint32_t result = (uint32_t)strtoul(str.c_str(), &end_ptr, 10); + if (*end_ptr != '\0') + throw std::runtime_error("Could not parse unsigned integer \"" + str + "\""); + return result; +} + +void load(const char* filename, MatrixXd& V, MatrixXi& F) +{ + /// Vertex indices used by the OBJ format + struct obj_vertex { + uint32_t p = (uint32_t)-1; + uint32_t n = (uint32_t)-1; + uint32_t uv = (uint32_t)-1; + + inline obj_vertex() { } + + inline obj_vertex(const std::string &string) { + std::vector<std::string> tokens = str_tokenize(string, '/', true); + + if (tokens.size() < 1 || tokens.size() > 3) + throw std::runtime_error("Invalid vertex data: \"" + string + "\""); + + p = str_to_uint32_t(tokens[0]); + +#if 0 + if (tokens.size() >= 2 && !tokens[1].empty()) + uv = str_to_uint32_t(tokens[1]); + + if (tokens.size() >= 3 && !tokens[2].empty()) + n = str_to_uint32_t(tokens[2]); +#endif + } + + inline bool operator==(const obj_vertex &v) const { + return v.p == p && v.n == n && v.uv == uv; + } + }; + + /// Hash function for obj_vertex + struct obj_vertexHash : std::unary_function<obj_vertex, size_t> { + std::size_t operator()(const obj_vertex &v) const { + size_t hash = std::hash<uint32_t>()(v.p); + hash = hash * 37 + std::hash<uint32_t>()(v.uv); + hash = hash * 37 + std::hash<uint32_t>()(v.n); + return hash; + } + }; + + typedef std::unordered_map<obj_vertex, uint32_t, obj_vertexHash> VertexMap; + + std::ifstream is(filename); + + std::vector<Vector3d> positions; + //std::vector<Vector2d> texcoords; + //std::vector<Vector3d> normals; + std::vector<uint32_t> indices; + std::vector<obj_vertex> vertices; + VertexMap vertexMap; + + std::string line_str; + while (std::getline(is, line_str)) { + std::istringstream line(line_str); + + std::string prefix; + line >> prefix; + + if (prefix == "v") { + Vector3d p; + line >> p.x() >> p.y() >> p.z(); + positions.push_back(p); + } + else if (prefix == "vt") { + /* + Vector2d tc; + line >> tc.x() >> tc.y(); + texcoords.push_back(tc); + */ + } + else if (prefix == "vn") { + /* + Vector3d n; + line >> n.x() >> n.y() >> n.z(); + normals.push_back(n); + */ + } + else if (prefix == "f") { + std::string v1, v2, v3, v4; + line >> v1 >> v2 >> v3 >> v4; + obj_vertex tri[6]; + int nVertices = 3; + + tri[0] = obj_vertex(v1); + tri[1] = obj_vertex(v2); + tri[2] = obj_vertex(v3); + + if (!v4.empty()) { + /* This is a quad, split into two triangles */ + tri[3] = obj_vertex(v4); + tri[4] = tri[0]; + tri[5] = tri[2]; + nVertices = 6; + } + /* Convert to an indexed vertex list */ + for (int i = 0; i<nVertices; ++i) { + const obj_vertex &v = tri[i]; + VertexMap::const_iterator it = vertexMap.find(v); + if (it == vertexMap.end()) { + vertexMap[v] = (uint32_t)vertices.size(); + indices.push_back((uint32_t)vertices.size()); + vertices.push_back(v); + } + else { + indices.push_back(it->second); + } + } + } + } + + F.resize(3, indices.size() / 3); + memcpy(F.data(), indices.data(), sizeof(uint32_t)*indices.size()); + + V.resize(3, vertices.size()); + for (uint32_t i = 0; i<vertices.size(); ++i) + V.col(i) = positions.at(vertices[i].p - 1); +} + +} // namespace qflow |