Sam Haves
91d3565cd5
PiperOrigin-RevId: 878041994 Change-Id: I6e7f6876e65fd2184ff5637d4268644cefcabecf
126 lines
3.9 KiB
C++
126 lines
3.9 KiB
C++
// Copyright 2026 DeepMind Technologies Limited
|
|
//
|
|
// 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 <cstring>
|
|
#include <string>
|
|
#include <string_view>
|
|
#include <vector>
|
|
|
|
#include <mujoco/mjplugin.h>
|
|
#include <mujoco/mjspec.h>
|
|
#include <mujoco/mujoco.h>
|
|
#include <tiny_obj_loader.h>
|
|
|
|
namespace {
|
|
|
|
mjSpec* Decode(mjResource* resource, const mjVFS* vfs) {
|
|
const void* bytes = nullptr;
|
|
int buffer_sz = mju_readResource(resource, &bytes);
|
|
if (buffer_sz < 0) {
|
|
mju_warning("obj_decoder: could not read OBJ file '%s'", resource->name);
|
|
return nullptr;
|
|
}
|
|
|
|
tinyobj::ObjReader obj_reader;
|
|
const char* buffer = static_cast<const char*>(bytes);
|
|
obj_reader.ParseFromString(std::string(buffer, buffer_sz), std::string());
|
|
|
|
if (!obj_reader.Valid()) {
|
|
mju_warning("obj_decoder: could not parse OBJ file '%s'", resource->name);
|
|
return nullptr;
|
|
}
|
|
|
|
mjSpec* spec = mj_makeSpec();
|
|
mjsMesh* mesh = mjs_addMesh(spec, nullptr);
|
|
|
|
const auto& attrib = obj_reader.GetAttrib();
|
|
|
|
std::vector<float> usernormal = attrib.normals;
|
|
std::vector<float> usertexcoord = attrib.texcoords;
|
|
std::vector<int> userface;
|
|
std::vector<int> userfacenormal;
|
|
std::vector<int> userfacetexcoord;
|
|
|
|
if (!obj_reader.GetShapes().empty()) {
|
|
const auto& obj_mesh = obj_reader.GetShapes()[0].mesh;
|
|
|
|
std::vector<tinyobj::index_t> face_indices;
|
|
for (size_t face = 0, idx = 0; idx < obj_mesh.indices.size();) {
|
|
int nfacevert = obj_mesh.num_face_vertices[face];
|
|
if (nfacevert < 3 || nfacevert > 4) {
|
|
mju_warning(
|
|
"obj_decoder: only tri or quad meshes are supported (file '%s')",
|
|
resource->name);
|
|
mj_deleteSpec(spec);
|
|
return nullptr;
|
|
}
|
|
|
|
face_indices.push_back(obj_mesh.indices[idx]);
|
|
face_indices.push_back(obj_mesh.indices[idx + 1]);
|
|
face_indices.push_back(obj_mesh.indices[idx + 2]);
|
|
|
|
if (nfacevert == 4) {
|
|
face_indices.push_back(obj_mesh.indices[idx]);
|
|
face_indices.push_back(obj_mesh.indices[idx + 2]);
|
|
face_indices.push_back(obj_mesh.indices[idx + 3]);
|
|
}
|
|
idx += nfacevert;
|
|
++face;
|
|
}
|
|
|
|
for (const auto& mesh_index : face_indices) {
|
|
userface.push_back(mesh_index.vertex_index);
|
|
|
|
if (!usernormal.empty()) {
|
|
userfacenormal.push_back(mesh_index.normal_index);
|
|
}
|
|
|
|
if (!usertexcoord.empty()) {
|
|
userfacetexcoord.push_back(mesh_index.texcoord_index);
|
|
}
|
|
}
|
|
}
|
|
|
|
for (size_t i = 0; i < usertexcoord.size() / 2; i++) {
|
|
usertexcoord[2 * i + 1] = 1 - usertexcoord[2 * i + 1];
|
|
}
|
|
|
|
mjs_setString(mesh->file, resource->name);
|
|
mjs_setFloat(mesh->uservert, attrib.vertices.data(), attrib.vertices.size());
|
|
mjs_setFloat(mesh->usernormal, usernormal.data(), usernormal.size());
|
|
mjs_setFloat(mesh->usertexcoord, usertexcoord.data(), usertexcoord.size());
|
|
mjs_setInt(mesh->userface, userface.data(), userface.size());
|
|
mjs_setInt(mesh->userfacenormal, userfacenormal.data(), userfacenormal.size());
|
|
mjs_setInt(mesh->userfacetexcoord, userfacetexcoord.data(), userfacetexcoord.size());
|
|
|
|
return spec;
|
|
}
|
|
|
|
int CanDecode(const mjResource* resource) {
|
|
std::string_view name(resource->name);
|
|
return name.ends_with(".obj") || name.ends_with(".OBJ");
|
|
}
|
|
|
|
} // namespace
|
|
|
|
mjPLUGIN_LIB_INIT {
|
|
mjpDecoder decoder;
|
|
mjp_defaultDecoder(&decoder);
|
|
decoder.content_type = "model/obj";
|
|
decoder.extension = ".obj";
|
|
decoder.decode = Decode;
|
|
decoder.can_decode = CanDecode;
|
|
mjp_registerDecoder(&decoder);
|
|
}
|