Add read support for Google's Draco (.drc) format.

cmake/modules/FindDraco.cmake

@@ -0,0 +1,26 @@
+set(_q "")
+if(${CMAKE_FIND_PACKAGE_NAME}_FIND_QUIETLY)
+    set(_q QUIET)
+    set(_quietly TRUE)
+endif()
+find_package(${CMAKE_FIND_PACKAGE_NAME} ${${CMAKE_FIND_PACKAGE_NAME}_FIND_VERSION} CONFIG ${_q})
+
+if (NOT ${CMAKE_FIND_PACKAGE_NAME}_FOUND)
+    include(CheckIncludeFileCXX)
+    add_library(draco INTERFACE)
+    target_include_directories(draco INTERFACE include)
+
+    if (_quietly)
+        set(CMAKE_REQUIRED_QUIET ON)
+    endif()
+    CHECK_INCLUDE_FILE_CXX("draco/draco_features.h" HAVE_DRACO_H)
+
+    if (NOT HAVE_DRACO_H)
+        if (${CMAKE_FIND_PACKAGE_NAME}_FIND_REQUIRED)
+            message(FATAL_ERROR "Draco library not found. Please install the dependency.")
+        elseif(NOT _quietly)
+            message(WARNING "Draco library not found.")
+        endif()
+    endif ()
+endif()
+

deps/CMakeLists.txt

@@ -294,6 +294,8 @@ include(CGAL/CGAL.cmake)
 include(NLopt/NLopt.cmake)
 include(libnoise/libnoise.cmake)
 
+include(Draco/Draco.cmake)
+
 
 # I *think* 1.1 is used for *just* md5 hashing?
 # 3.1 has everything in the right place, but the md5 funcs used are deprecated
@@ -357,6 +359,7 @@ set(_dep_list
     ${CURL_PKG}
     ${WXWIDGETS_PKG}
     dep_Cereal
+    dep_Draco
     dep_NLopt
     dep_OpenVDB
     dep_OpenCSG

deps/Draco/Draco.cmake

@@ -0,0 +1,4 @@
+orcaslicer_add_cmake_project(Draco
+    URL https://github.com/google/draco/archive/refs/tags/1.5.7.zip
+    URL_HASH SHA256=27b72ba2d5ff3d0a9814ad40d4cb88f8dc89a35491c0866d952473f8f9416b77
+)

src/libslic3r/CMakeLists.txt

@@ -133,6 +133,8 @@ set(lisbslic3r_sources
     Format/bbs_3mf.hpp
     Format/AMF.cpp
     Format/AMF.hpp
+    Format/DRC.cpp
+    Format/DRC.hpp
     Format/OBJ.cpp
     Format/OBJ.hpp
     Format/objparser.cpp
@@ -522,6 +524,7 @@ find_package(OpenCASCADE REQUIRED)
 target_include_directories(libslic3r PUBLIC ${OpenCASCADE_INCLUDE_DIR})
 
 find_package(JPEG REQUIRED)
+find_package(draco REQUIRED)
 
 set(OCCT_LIBS
     TKXDESTEP
@@ -578,6 +581,7 @@ target_link_libraries(libslic3r
     qoi
     opencv_world
     noise::noise
+    draco::draco
     )
 
 if(NOT WIN32)

src/libslic3r/Format/DRC.cpp

@@ -0,0 +1,126 @@
+#include <string>
+#include <utility>
+#include <cstring>
+
+#include <draco/compression/decode.h>
+#include <draco/io/mesh_io.h>
+#include <draco/mesh/mesh.h>
+using namespace draco;
+
+#include "libslic3r/Model.hpp"
+#include "libslic3r/TriangleMesh.hpp"
+#include "DRC.hpp"
+
+#ifdef _WIN32
+#define DIR_SEPARATOR '\\'
+#else
+#define DIR_SEPARATOR '/'
+#endif
+
+namespace Slic3r {
+
+bool load_drc(const char *path, TriangleMesh *meshptr)
+{
+    struct stat st;
+    if (stat(path, &st)) {
+        return false;
+    }
+
+    FILE *fp = fopen(path, "rb");
+    if (fp == nullptr) {
+        return false;
+    }
+
+    char *data = new char[st.st_size];
+    if (fread(data, 1, st.st_size, fp) != st.st_size) {
+        fclose(fp);
+        delete[] data;
+        return false;
+    }
+    fclose(fp);
+    
+    DecoderBuffer buffer;
+    buffer.Init(data, st.st_size);
+
+    auto geotype = Decoder::GetEncodedGeometryType(&buffer);
+    if ((!geotype.ok()) || geotype.value() != TRIANGULAR_MESH) {
+        delete[] data;
+        return false;
+    }
+    
+    Decoder decoder;
+    Mesh dracoMesh;
+    Status status = decoder.DecodeBufferToGeometry(&buffer, &dracoMesh);
+    delete[] data;
+    if (!status.ok()) {
+        return false;
+    }
+    
+    indexed_triangle_set its;
+    
+    const PointAttribute *const positions = dracoMesh.GetNamedAttribute(GeometryAttribute::POSITION);    
+    size_t num_vertices = positions->size();
+    its.vertices.reserve(num_vertices);
+    for (AttributeValueIndex i(0); i < num_vertices; ++ i) {
+        float pos[3];
+        positions->ConvertValue<float>(i, 3, pos);
+        its.vertices.emplace_back(pos[0], pos[1], pos[2]);
+    }
+    
+    size_t num_faces = dracoMesh.num_faces();
+    its.indices.reserve(num_faces);
+    for (FaceIndex i(0); i < num_faces; ++ i) {
+        Mesh::Face face = dracoMesh.face(i);
+        
+        its.indices.emplace_back(
+            positions->mapped_index(face[0]).value(),
+            positions->mapped_index(face[1]).value(),
+            positions->mapped_index(face[2]).value()
+        );
+    }
+
+    *meshptr = TriangleMesh(std::move(its));
+    if (meshptr->volume() < 0)
+        meshptr->flip_triangles();
+    return true;
+}
+
+bool load_drc(const char *path, Model *model, const char *object_name_in)
+{
+    TriangleMesh mesh;
+    
+    bool ret = load_drc(path, &mesh);
+    
+    if (ret) {
+        std::string  object_name;
+        if (object_name_in == nullptr) {
+            const char *last_slash = strrchr(path, DIR_SEPARATOR);
+            object_name.assign((last_slash == nullptr) ? path : last_slash + 1);
+        } else
+           object_name.assign(object_name_in);
+    
+        model->add_object(object_name.c_str(), path, std::move(mesh));
+    }
+    
+    return ret;
+}
+
+bool store_drc(const char *path, TriangleMesh *mesh, bool binary)
+{
+    // TODO
+    return false;
+}
+
+bool store_drc(const char *path, ModelObject *model_object, bool binary)
+{
+    TriangleMesh mesh = model_object->mesh();
+    return store_drc(path, &mesh, binary);
+}
+
+bool store_drc(const char *path, Model *model, bool binary)
+{
+    TriangleMesh mesh = model->mesh();
+    return store_drc(path, &mesh, binary);
+}
+
+}; // namespace Slic3r

src/libslic3r/Format/DRC.hpp

@@ -0,0 +1,20 @@
+#ifndef slic3r_Format_DRC_hpp_
+#define slic3r_Format_DRC_hpp_
+
+namespace Slic3r {
+
+class TriangleMesh;
+class ModelObject;
+class Model;
+
+// Load a Draco file into a provided model.
+extern bool load_drc(const char *path, TriangleMesh *meshptr);
+extern bool load_drc(const char *path, Model *model, const char *object_name = nullptr);
+
+extern bool store_drc(const char *path, TriangleMesh *mesh, bool binary);
+extern bool store_drc(const char *path, ModelObject *model_object, bool binary);
+extern bool store_drc(const char *path, Model *model, bool binary);
+
+}; // namespace Slic3r
+
+#endif /* slic3r_Format_DRC_hpp_ */

src/libslic3r/Model.cpp

@@ -12,6 +12,7 @@
 
 #include "Format/AMF.hpp"
 #include "Format/svg.hpp"
+#include "Format/DRC.hpp"
 // BBS
 #include "FaceDetector.hpp"
 
@@ -300,6 +301,8 @@ Model Model::read_from_file(const std::string&
         result = load_svg(input_file.c_str(), &model, message);
     //BBS: remove the old .amf.xml files
     //else if (boost::algorithm::iends_with(input_file, ".amf") || boost::algorithm::iends_with(input_file, ".amf.xml"))
+    else if (boost::algorithm::iends_with(input_file, ".drc"))
+        result = load_drc(input_file.c_str(), &model);
     else if (boost::algorithm::iends_with(input_file, ".amf"))
         //BBS: is_xxx is used for is_inches when load amf
         result = load_amf(input_file.c_str(), config, config_substitutions, &model, is_xxx);

src/slic3r/GUI/GUI_App.cpp

@@ -516,10 +516,10 @@ static const FileWildcards file_wildcards_by_type[FT_SIZE] = {
     /* FT_GCODE */   { "G-code files"sv,    { ".gcode"sv} },
 #ifdef __APPLE__
     /* FT_MODEL */
-    {"Supported files"sv, {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv, ".usd"sv, ".usda"sv, ".usdc"sv, ".usdz"sv, ".abc"sv, ".ply"sv}},
+    {"Supported files"sv, {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv, ".usd"sv, ".usda"sv, ".usdc"sv, ".usdz"sv, ".abc"sv, ".ply"sv, ".drc"sv}},
 #else
     /* FT_MODEL */
-    {"Supported files"sv, {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv}},
+    {"Supported files"sv, {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv, ".drc"sv}},
 #endif
     /* FT_ZIP */     { "ZIP files"sv,       { ".zip"sv } },
     /* FT_PROJECT */ { "Project files"sv,   { ".3mf"sv} },

src/slic3r/GUI/Plater.cpp

@@ -10946,7 +10946,7 @@ void ProjectDropDialog::on_dpi_changed(const wxRect& suggested_rect)
 //BBS: remove GCodeViewer as seperate APP logic
 bool Plater::load_files(const wxArrayString& filenames)
 {
-    const std::regex pattern_drop(".*[.](stp|step|stl|oltp|obj|amf|3mf|svg|zip)", std::regex::icase);
+    const std::regex pattern_drop(".*[.](stp|step|stl|oltp|obj|amf|3mf|svg|zip|drc)", std::regex::icase);
     const std::regex pattern_gcode_drop(".*[.](gcode|g)", std::regex::icase);
 
     std::vector<fs::path> normal_paths;