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extern/gltf-draco/draco/src/draco/io/obj_decoder.cc

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// Copyright 2016 The Draco Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#include "draco/io/obj_decoder.h"
#include <cctype>
#include <cmath>
#include <fstream>
#include "draco/io/parser_utils.h"
#include "draco/metadata/geometry_metadata.h"
namespace draco {
ObjDecoder::ObjDecoder()
: counting_mode_(true),
num_obj_faces_(0),
num_positions_(0),
num_tex_coords_(0),
num_normals_(0),
num_materials_(0),
last_sub_obj_id_(0),
pos_att_id_(-1),
tex_att_id_(-1),
norm_att_id_(-1),
material_att_id_(-1),
sub_obj_att_id_(-1),
deduplicate_input_values_(true),
last_material_id_(0),
use_metadata_(false),
out_mesh_(nullptr),
out_point_cloud_(nullptr) {}
Status ObjDecoder::DecodeFromFile(const std::string &file_name,
Mesh *out_mesh) {
out_mesh_ = out_mesh;
return DecodeFromFile(file_name, static_cast<PointCloud *>(out_mesh));
}
Status ObjDecoder::DecodeFromFile(const std::string &file_name,
PointCloud *out_point_cloud) {
std::ifstream file(file_name, std::ios::binary);
if (!file)
return Status(Status::IO_ERROR);
// Read the whole file into a buffer.
auto pos0 = file.tellg();
file.seekg(0, std::ios::end);
auto file_size = file.tellg() - pos0;
if (file_size == 0)
return Status(Status::IO_ERROR);
file.seekg(0, std::ios::beg);
std::vector<char> data(file_size);
file.read(&data[0], file_size);
buffer_.Init(&data[0], file_size);
out_point_cloud_ = out_point_cloud;
input_file_name_ = file_name;
return DecodeInternal();
}
Status ObjDecoder::DecodeFromBuffer(DecoderBuffer *buffer, Mesh *out_mesh) {
out_mesh_ = out_mesh;
return DecodeFromBuffer(buffer, static_cast<PointCloud *>(out_mesh));
}
Status ObjDecoder::DecodeFromBuffer(DecoderBuffer *buffer,
PointCloud *out_point_cloud) {
out_point_cloud_ = out_point_cloud;
buffer_.Init(buffer->data_head(), buffer->remaining_size());
return DecodeInternal();
}
Status ObjDecoder::DecodeInternal() {
// In the first pass, count the number of different elements in the geometry.
// In case the desired output is just a point cloud (i.e., when
// out_mesh_ == nullptr) the decoder will ignore all information about the
// connectivity that may be included in the source data.
counting_mode_ = true;
ResetCounters();
material_name_to_id_.clear();
last_sub_obj_id_ = 0;
// Parse all lines.
Status status(Status::OK);
while (ParseDefinition(&status) && status.ok()) {
}
if (!status.ok())
return status;
bool use_identity_mapping = false;
if (num_obj_faces_ == 0) {
// Mesh has no faces. In this case we try to read the geometry as a point
// cloud where every attribute entry is a point.
// Ensure the number of all entries is same for all attributes.
if (num_positions_ == 0)
return Status(Status::ERROR, "No position attribute");
if (num_tex_coords_ > 0 && num_tex_coords_ != num_positions_)
return Status(Status::ERROR,
"Invalid number of texture coordinates for a point cloud");
if (num_normals_ > 0 && num_normals_ != num_positions_)
return Status(Status::ERROR,
"Invalid number of normals for a point cloud");
out_mesh_ = nullptr; // Treat the output geometry as a point cloud.
use_identity_mapping = true;
}
// Initialize point cloud and mesh properties.
if (out_mesh_) {
// Start decoding a mesh with the given number of faces. For point clouds we
// silently ignore all data about the mesh connectivity.
out_mesh_->SetNumFaces(num_obj_faces_);
}
if (num_obj_faces_ > 0) {
out_point_cloud_->set_num_points(3 * num_obj_faces_);
} else {
out_point_cloud_->set_num_points(num_positions_);
}
// Add attributes if they are present in the input data.
if (num_positions_ > 0) {
GeometryAttribute va;
va.Init(GeometryAttribute::POSITION, nullptr, 3, DT_FLOAT32, false,
sizeof(float) * 3, 0);
pos_att_id_ = out_point_cloud_->AddAttribute(va, use_identity_mapping,
num_positions_);
}
if (num_tex_coords_ > 0) {
GeometryAttribute va;
va.Init(GeometryAttribute::TEX_COORD, nullptr, 2, DT_FLOAT32, false,
sizeof(float) * 2, 0);
tex_att_id_ = out_point_cloud_->AddAttribute(va, use_identity_mapping,
num_tex_coords_);
}
if (num_normals_ > 0) {
GeometryAttribute va;
va.Init(GeometryAttribute::NORMAL, nullptr, 3, DT_FLOAT32, false,
sizeof(float) * 3, 0);
norm_att_id_ =
out_point_cloud_->AddAttribute(va, use_identity_mapping, num_normals_);
}
if (num_materials_ > 0 && num_obj_faces_ > 0) {
GeometryAttribute va;
if (num_materials_ < 256) {
va.Init(GeometryAttribute::GENERIC, nullptr, 1, DT_UINT8, false, 1, 0);
} else if (num_materials_ < (1 << 16)) {
va.Init(GeometryAttribute::GENERIC, nullptr, 1, DT_UINT16, false, 2, 0);
} else {
va.Init(GeometryAttribute::GENERIC, nullptr, 1, DT_UINT32, false, 4, 0);
}
material_att_id_ =
out_point_cloud_->AddAttribute(va, false, num_materials_);
// Fill the material entries.
for (int i = 0; i < num_materials_; ++i) {
const AttributeValueIndex avi(i);
out_point_cloud_->attribute(material_att_id_)->SetAttributeValue(avi, &i);
}
if (use_metadata_) {
// Use metadata to store the name of materials.
std::unique_ptr<AttributeMetadata> material_metadata =
std::unique_ptr<AttributeMetadata>(new AttributeMetadata());
material_metadata->AddEntryString("name", "material");
// Add all material names.
for (const auto &itr : material_name_to_id_) {
material_metadata->AddEntryInt(itr.first, itr.second);
}
if (!material_file_name_.empty()) {
material_metadata->AddEntryString("file_name", material_file_name_);
}
out_point_cloud_->AddAttributeMetadata(material_att_id_,
std::move(material_metadata));
}
}
if (!obj_name_to_id_.empty() && num_obj_faces_ > 0) {
GeometryAttribute va;
if (obj_name_to_id_.size() < 256) {
va.Init(GeometryAttribute::GENERIC, nullptr, 1, DT_UINT8, false, 1, 0);
} else if (obj_name_to_id_.size() < (1 << 16)) {
va.Init(GeometryAttribute::GENERIC, nullptr, 1, DT_UINT16, false, 2, 0);
} else {
va.Init(GeometryAttribute::GENERIC, nullptr, 1, DT_UINT32, false, 4, 0);
}
sub_obj_att_id_ = out_point_cloud_->AddAttribute(
va, false, static_cast<uint32_t>(obj_name_to_id_.size()));
// Fill the sub object id entries.
for (const auto &itr : obj_name_to_id_) {
const AttributeValueIndex i(itr.second);
out_point_cloud_->attribute(sub_obj_att_id_)->SetAttributeValue(i, &i);
}
if (use_metadata_) {
// Use metadata to store the name of materials.
std::unique_ptr<AttributeMetadata> sub_obj_metadata =
std::unique_ptr<AttributeMetadata>(new AttributeMetadata());
sub_obj_metadata->AddEntryString("name", "sub_obj");
// Add all sub object names.
for (const auto &itr : obj_name_to_id_) {
const AttributeValueIndex i(itr.second);
sub_obj_metadata->AddEntryInt(itr.first, itr.second);
}
out_point_cloud_->AddAttributeMetadata(sub_obj_att_id_,
std::move(sub_obj_metadata));
}
}
// Perform a second iteration of parsing and fill all the data.
counting_mode_ = false;
ResetCounters();
// Start parsing from the beginning of the buffer again.
buffer()->StartDecodingFrom(0);
while (ParseDefinition(&status) && status.ok()) {
}
if (!status.ok())
return status;
if (out_mesh_) {
// Add faces with identity mapping between vertex and corner indices.
// Duplicate vertices will get removed later.
Mesh::Face face;
for (FaceIndex i(0); i < num_obj_faces_; ++i) {
for (int c = 0; c < 3; ++c)
face[c] = 3 * i.value() + c;
out_mesh_->SetFace(i, face);
}
}
#ifdef DRACO_ATTRIBUTE_DEDUPLICATION_SUPPORTED
if (deduplicate_input_values_) {
out_point_cloud_->DeduplicateAttributeValues();
}
out_point_cloud_->DeduplicatePointIds();
#endif
return status;
}
void ObjDecoder::ResetCounters() {
num_obj_faces_ = 0;
num_positions_ = 0;
num_tex_coords_ = 0;
num_normals_ = 0;
last_material_id_ = 0;
last_sub_obj_id_ = 0;
}
bool ObjDecoder::ParseDefinition(Status *status) {
char c;
parser::SkipWhitespace(buffer());
if (!buffer()->Peek(&c)) {
// End of file reached?.
return false;
}
if (c == '#') {
// Comment, ignore the line.
parser::SkipLine(buffer());
return true;
}
if (ParseVertexPosition(status))
return true;
if (ParseNormal(status))
return true;
if (ParseTexCoord(status))
return true;
if (ParseFace(status))
return true;
if (ParseMaterial(status))
return true;
if (ParseMaterialLib(status))
return true;
if (ParseObject(status))
return true;
// No known definition was found. Ignore the line.
parser::SkipLine(buffer());
return true;
}
bool ObjDecoder::ParseVertexPosition(Status *status) {
std::array<char, 2> c;
if (!buffer()->Peek(&c)) {
return false;
}
if (c[0] != 'v' || c[1] != ' ')
return false;
// Vertex definition found!
buffer()->Advance(2);
if (!counting_mode_) {
// Parse three float numbers for vertex position coordinates.
float val[3];
for (int i = 0; i < 3; ++i) {
parser::SkipWhitespace(buffer());
if (!parser::ParseFloat(buffer(), val + i)) {
*status = Status(Status::ERROR, "Failed to parse a float number");
// The definition is processed so return true.
return true;
}
}
out_point_cloud_->attribute(pos_att_id_)
->SetAttributeValue(AttributeValueIndex(num_positions_), val);
}
++num_positions_;
parser::SkipLine(buffer());
return true;
}
bool ObjDecoder::ParseNormal(Status *status) {
std::array<char, 2> c;
if (!buffer()->Peek(&c)) {
return false;
}
if (c[0] != 'v' || c[1] != 'n')
return false;
// Normal definition found!
buffer()->Advance(2);
if (!counting_mode_) {
// Parse three float numbers for the normal vector.
float val[3];
for (int i = 0; i < 3; ++i) {
parser::SkipWhitespace(buffer());
if (!parser::ParseFloat(buffer(), val + i)) {
*status = Status(Status::ERROR, "Failed to parse a float number");
// The definition is processed so return true.
return true;
}
}
out_point_cloud_->attribute(norm_att_id_)
->SetAttributeValue(AttributeValueIndex(num_normals_), val);
}
++num_normals_;
parser::SkipLine(buffer());
return true;
}
bool ObjDecoder::ParseTexCoord(Status *status) {
std::array<char, 2> c;
if (!buffer()->Peek(&c)) {
return false;
}
if (c[0] != 'v' || c[1] != 't')
return false;
// Texture coord definition found!
buffer()->Advance(2);
if (!counting_mode_) {
// Parse two float numbers for the texture coordinate.
float val[2];
for (int i = 0; i < 2; ++i) {
parser::SkipWhitespace(buffer());
if (!parser::ParseFloat(buffer(), val + i)) {
*status = Status(Status::ERROR, "Failed to parse a float number");
// The definition is processed so return true.
return true;
}
}
out_point_cloud_->attribute(tex_att_id_)
->SetAttributeValue(AttributeValueIndex(num_tex_coords_), val);
}
++num_tex_coords_;
parser::SkipLine(buffer());
return true;
}
bool ObjDecoder::ParseFace(Status *status) {
char c;
if (!buffer()->Peek(&c)) {
return false;
}
if (c != 'f')
return false;
// Face definition found!
buffer()->Advance(1);
if (!counting_mode_) {
std::array<int32_t, 3> indices[4];
// Parse face indices (we try to look for up to four to support quads).
int num_valid_indices = 0;
for (int i = 0; i < 4; ++i) {
if (!ParseVertexIndices(&indices[i])) {
if (i == 3) {
break; // It's OK if there is no fourth vertex index.
}
*status = Status(Status::ERROR, "Failed to parse vertex indices");
return true;
}
++num_valid_indices;
}
// Process the first face.
for (int i = 0; i < 3; ++i) {
const PointIndex vert_id(3 * num_obj_faces_ + i);
MapPointToVertexIndices(vert_id, indices[i]);
}
++num_obj_faces_;
if (num_valid_indices == 4) {
// Add an additional triangle for the quad.
//
// 3----2
// | / |
// | / |
// 0----1
//
const PointIndex vert_id(3 * num_obj_faces_);
MapPointToVertexIndices(vert_id, indices[0]);
MapPointToVertexIndices(vert_id + 1, indices[2]);
MapPointToVertexIndices(vert_id + 2, indices[3]);
++num_obj_faces_;
}
} else {
// We are in the counting mode.
// We need to determine how many triangles are in the obj face.
// Go over the line and check how many gaps there are between non-empty
// sub-strings.
parser::SkipWhitespace(buffer());
int num_indices = 0;
bool is_end = false;
while (buffer()->Peek(&c) && c != '\n') {
if (parser::PeekWhitespace(buffer(), &is_end)) {
buffer()->Advance(1);
} else {
// Non-whitespace reached.. assume it's index declaration, skip it.
num_indices++;
while (!parser::PeekWhitespace(buffer(), &is_end) && !is_end) {
buffer()->Advance(1);
}
}
}
if (num_indices < 3 || num_indices > 4) {
*status = Status(Status::ERROR, "Invalid number of indices on a face");
return false;
}
// Either one or two new triangles.
num_obj_faces_ += num_indices - 2;
}
parser::SkipLine(buffer());
return true;
}
bool ObjDecoder::ParseMaterialLib(Status *status) {
// Allow only one material library per file for now.
if (material_name_to_id_.size() > 0)
return false;
std::array<char, 6> c;
if (!buffer()->Peek(&c)) {
return false;
}
if (std::memcmp(&c[0], "mtllib", 6) != 0)
return false;
buffer()->Advance(6);
DecoderBuffer line_buffer = parser::ParseLineIntoDecoderBuffer(buffer());
parser::SkipWhitespace(&line_buffer);
material_file_name_.clear();
if (!parser::ParseString(&line_buffer, &material_file_name_)) {
*status = Status(Status::ERROR, "Failed to parse material file name");
return true;
}
parser::SkipLine(&line_buffer);
if (material_file_name_.size() > 0) {
if (!ParseMaterialFile(material_file_name_, status)) {
// Silently ignore problems with material files for now.
return true;
}
}
return true;
}
bool ObjDecoder::ParseMaterial(Status * /* status */) {
// In second pass, skip when we don't use materials.
if (!counting_mode_ && material_att_id_ < 0)
return false;
std::array<char, 6> c;
if (!buffer()->Peek(&c)) {
return false;
}
if (std::memcmp(&c[0], "usemtl", 6) != 0)
return false;
buffer()->Advance(6);
DecoderBuffer line_buffer = parser::ParseLineIntoDecoderBuffer(buffer());
parser::SkipWhitespace(&line_buffer);
std::string mat_name;
parser::ParseLine(&line_buffer, &mat_name);
if (mat_name.length() == 0)
return false;
auto it = material_name_to_id_.find(mat_name);
if (it == material_name_to_id_.end()) {
// In first pass, materials found in obj that's not in the .mtl file
// will be added to the list.
last_material_id_ = num_materials_;
material_name_to_id_[mat_name] = num_materials_++;
return true;
}
last_material_id_ = it->second;
return true;
}
bool ObjDecoder::ParseObject(Status *status) {
std::array<char, 2> c;
if (!buffer()->Peek(&c)) {
return false;
}
if (std::memcmp(&c[0], "o ", 2) != 0)
return false;
buffer()->Advance(1);
DecoderBuffer line_buffer = parser::ParseLineIntoDecoderBuffer(buffer());
parser::SkipWhitespace(&line_buffer);
std::string obj_name;
if (!parser::ParseString(&line_buffer, &obj_name))
return false;
if (obj_name.length() == 0)
return true; // Ignore empty name entries.
auto it = obj_name_to_id_.find(obj_name);
if (it == obj_name_to_id_.end()) {
const int num_obj = static_cast<int>(obj_name_to_id_.size());
obj_name_to_id_[obj_name] = num_obj;
last_sub_obj_id_ = num_obj;
} else {
last_sub_obj_id_ = it->second;
}
return true;
}
bool ObjDecoder::ParseVertexIndices(std::array<int32_t, 3> *out_indices) {
// Parsed attribute indices can be in format:
// 1. POS_INDEX
// 2. POS_INDEX/TEX_COORD_INDEX
// 3. POS_INDEX/TEX_COORD_INDEX/NORMAL_INDEX
// 4. POS_INDEX//NORMAL_INDEX
parser::SkipCharacters(buffer(), " \t");
if (!parser::ParseSignedInt(buffer(), &(*out_indices)[0]) ||
(*out_indices)[0] == 0)
return false; // Position index must be present and valid.
(*out_indices)[1] = (*out_indices)[2] = 0;
char ch;
if (!buffer()->Peek(&ch))
return true; // It may be OK if we cannot read any more characters.
if (ch != '/')
return true;
buffer()->Advance(1);
// Check if we should skip texture index or not.
if (!buffer()->Peek(&ch))
return false; // Here, we should be always able to read the next char.
if (ch != '/') {
// Must be texture coord index.
if (!parser::ParseSignedInt(buffer(), &(*out_indices)[1]) ||
(*out_indices)[1] == 0)
return false; // Texture index must be present and valid.
}
if (!buffer()->Peek(&ch))
return true;
if (ch == '/') {
buffer()->Advance(1);
// Read normal index.
if (!parser::ParseSignedInt(buffer(), &(*out_indices)[2]) ||
(*out_indices)[2] == 0)
return false; // Normal index must be present and valid.
}
return true;
}
void ObjDecoder::MapPointToVertexIndices(
PointIndex vert_id, const std::array<int32_t, 3> &indices) {
// Use face entries to store mapping between vertex and attribute indices
// (positions, texture coordinates and normal indices).
// Any given index is used when indices[x] != 0. For positive values, the
// point is mapped directly to the specified attribute index. Negative input
// indices indicate addressing from the last element (e.g. -1 is the last
// attribute value of a given type, -2 the second last, etc.).
if (indices[0] > 0) {
out_point_cloud_->attribute(pos_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(indices[0] - 1));
} else if (indices[0] < 0) {
out_point_cloud_->attribute(pos_att_id_)
->SetPointMapEntry(vert_id,
AttributeValueIndex(num_positions_ + indices[0]));
}
if (tex_att_id_ >= 0) {
if (indices[1] > 0) {
out_point_cloud_->attribute(tex_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(indices[1] - 1));
} else if (indices[1] < 0) {
out_point_cloud_->attribute(tex_att_id_)
->SetPointMapEntry(vert_id,
AttributeValueIndex(num_tex_coords_ + indices[1]));
} else {
// Texture index not provided but expected. Insert 0 entry as the
// default value.
out_point_cloud_->attribute(tex_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(0));
}
}
if (norm_att_id_ >= 0) {
if (indices[2] > 0) {
out_point_cloud_->attribute(norm_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(indices[2] - 1));
} else if (indices[2] < 0) {
out_point_cloud_->attribute(norm_att_id_)
->SetPointMapEntry(vert_id,
AttributeValueIndex(num_normals_ + indices[2]));
} else {
// Normal index not provided but expected. Insert 0 entry as the default
// value.
out_point_cloud_->attribute(norm_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(0));
}
}
// Assign material index to the point if it is available.
if (material_att_id_ >= 0) {
out_point_cloud_->attribute(material_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(last_material_id_));
}
// Assign sub-object index to the point if it is available.
if (sub_obj_att_id_ >= 0) {
out_point_cloud_->attribute(sub_obj_att_id_)
->SetPointMapEntry(vert_id, AttributeValueIndex(last_sub_obj_id_));
}
}
bool ObjDecoder::ParseMaterialFile(const std::string &file_name,
Status *status) {
// Get the correct path to the |file_name| using the folder from
// |input_file_name_| as the root folder.
const auto pos = input_file_name_.find_last_of("/\\");
std::string full_path;
if (pos != std::string::npos) {
full_path = input_file_name_.substr(0, pos + 1);
}
full_path += file_name;
std::ifstream file(full_path, std::ios::binary);
if (!file)
return false;
// Read the whole file into a buffer.
file.seekg(0, std::ios::end);
const std::string::size_type file_size = file.tellg();
if (file_size == 0)
return false;
file.seekg(0, std::ios::beg);
std::vector<char> data(file_size);
file.read(&data[0], file_size);
// Backup the original decoder buffer.
DecoderBuffer old_buffer = buffer_;
buffer_.Init(&data[0], file_size);
num_materials_ = 0;
while (ParseMaterialFileDefinition(status)) {
}
// Restore the original buffer.
buffer_ = old_buffer;
return true;
}
bool ObjDecoder::ParseMaterialFileDefinition(Status * /* status */) {
char c;
parser::SkipWhitespace(buffer());
if (!buffer()->Peek(&c)) {
// End of file reached?.
return false;
}
if (c == '#') {
// Comment, ignore the line.
parser::SkipLine(buffer());
return true;
}
std::string str;
if (!parser::ParseString(buffer(), &str))
return false;
if (str.compare("newmtl") == 0) {
parser::SkipWhitespace(buffer());
parser::ParseLine(buffer(), &str);
if (str.length() == 0)
return false;
// Add new material to our map.
material_name_to_id_[str] = num_materials_++;
}
parser::SkipLine(buffer());
return true;
}
} // namespace draco