assimp

deps/Assimp/Assimp.cmake

@@ -0,0 +1,40 @@
+if(CMAKE_VERSION VERSION_LESS 3.22)
+    set(_assimp_url "https://github.com/assimp/assimp/archive/refs/tags/v5.3.1.tar.gz")
+    set(_assimp_hash "SHA256=a07666be71afe1ad4bc008c2336b7c688aca391271188eb9108d0c6db1be53f1")
+else()
+    set(_assimp_url "https://github.com/assimp/assimp/archive/refs/tags/v5.4.3.tar.gz")
+    set(_assimp_hash "SHA256=66dfbaee288f2bc43172440a55d0235dfc7bf885dda6435c038e8000e79582cb")
+endif()
+
+# Assimp's bundled zlib (contrib/zlib) is too old to compile against the modern
+# macOS SDK: its zutil.h takes the classic-Mac branch under TARGET_OS_MAC and
+# does `#define fdopen(fd,mode) NULL`, which then clobbers the SDK's real
+# `fdopen` prototype in <stdio.h> and breaks the build. On macOS use the system
+# zlib (already found by find_package(ZLIB) in deps-unix-common) instead.
+if(APPLE)
+    set(_assimp_build_zlib "-DASSIMP_BUILD_ZLIB=OFF")
+else()
+    set(_assimp_build_zlib "-DASSIMP_BUILD_ZLIB=ON")
+endif()
+
+orcaslicer_add_cmake_project(Assimp
+    URL ${_assimp_url}
+    URL_HASH ${_assimp_hash}
+    CMAKE_ARGS
+        -DASSIMP_BUILD_TESTS=OFF
+        -DASSIMP_BUILD_SAMPLES=OFF
+        -DASSIMP_BUILD_ASSIMP_TOOLS=OFF
+        -DASSIMP_INSTALL_PDB=OFF
+        -DASSIMP_NO_EXPORT=ON
+        -DASSIMP_BUILD_ALL_IMPORTERS_BY_DEFAULT=OFF
+        -DASSIMP_BUILD_GLTF_IMPORTER=ON
+        -DASSIMP_BUILD_OBJ_IMPORTER=ON
+        -DASSIMP_BUILD_FBX_IMPORTER=ON
+        ${_assimp_build_zlib}
+        -DASSIMP_WARNINGS_AS_ERRORS=OFF
+        -DBUILD_WITH_STATIC_CRT=OFF
+)
+
+if (MSVC)
+    add_debug_dep(dep_Assimp)
+endif ()

deps/CMakeLists.txt

@@ -367,6 +367,9 @@ include(libnoise/libnoise.cmake)
 
 include(Draco/Draco.cmake)
 
+# Assimp: glTF/GLB/FBX import for the texture-to-color feature.
+include(Assimp/Assimp.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
@@ -448,6 +451,7 @@ set(_dep_list
     dep_libnoise
     dep_python3
     dep_wxInspector
+    dep_Assimp
     )
 
 if (MSVC)

src/libslic3r/CMakeLists.txt

@@ -205,6 +205,8 @@ set(lisbslic3r_sources
     format.hpp
     Format/OBJ.cpp
     Format/OBJ.hpp
+    Format/AssimpImport.hpp
+    Format/AssimpImport.cpp
     Format/ResourcePathUtils.hpp
     Format/objparser.cpp
     Format/objparser.hpp
@@ -521,6 +523,7 @@ cmake_policy(SET CMP0011 NEW)
 set(CMAKE_POLICY_DEFAULT_CMP0167 NEW)
 find_package(CGAL REQUIRED)
 find_package(OpenCV REQUIRED core)
+find_package(assimp REQUIRED)
 unset(CMAKE_POLICY_DEFAULT_CMP0167)
 cmake_policy(POP)
 
@@ -609,6 +612,7 @@ target_link_libraries(libslic3r
         libnest2d
         miniz
         opencv_world
+        assimp::assimp
     PRIVATE
         ${CMAKE_DL_LIBS}
         ${EXPAT_LIBRARIES}

src/libslic3r/Format/AssimpImport.cpp

@@ -0,0 +1,327 @@
+#include "AssimpImport.hpp"
+
+#include "../TexturePainting.hpp"
+#include "ResourcePathUtils.hpp"
+
+#include <assimp/Importer.hpp>
+#include <assimp/config.h>
+#include <assimp/material.h>
+#include <assimp/postprocess.h>
+#include <assimp/scene.h>
+
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/filesystem.hpp>
+#include <boost/log/trivial.hpp>
+#include <boost/nowide/fstream.hpp>
+
+#include <array>
+#include <cstdint>
+#include <limits>
+#include <sstream>
+#include <string>
+#include <vector>
+
+namespace Slic3r {
+namespace {
+
+void clear_textured_mesh(TexturedMesh& out)
+{
+    out.vertices.clear();
+    out.indices.clear();
+    out.uvs.clear();
+    out.uv_coords.clear();
+    out.uv_indices.clear();
+    out.textures.clear();
+    out.material_ids.clear();
+    out.material_texture_map.clear();
+    out.material_colors.clear();
+}
+
+void set_error_message(std::string* error_message, const std::string& message)
+{
+    if (error_message)
+        *error_message = message;
+}
+
+bool is_fbx_path(const std::string& path)
+{
+    return boost::algorithm::iends_with(path, ".fbx");
+}
+
+bool should_flip_uvs(const std::string& path)
+{
+    return boost::algorithm::iends_with(path, ".fbx") ||
+           boost::algorithm::iends_with(path, ".glb");
+}
+
+unsigned int assimp_import_flags(const std::string& path)
+{
+    unsigned int flags = aiProcess_Triangulate
+                       | aiProcess_GenNormals
+                       | aiProcess_PreTransformVertices
+                       | aiProcess_SortByPType;
+    if (should_flip_uvs(path))
+        flags |= aiProcess_FlipUVs;
+    return flags;
+}
+
+void configure_importer(Assimp::Importer& importer, const std::string& path, unsigned int flags)
+{
+    importer.SetPropertyInteger(AI_CONFIG_PP_SBP_REMOVE,
+        aiPrimitiveType_POINT | aiPrimitiveType_LINE);
+
+    if (flags & aiProcess_PreTransformVertices)
+        importer.SetPropertyBool(AI_CONFIG_PP_PTV_KEEP_HIERARCHY, true);
+
+    if (is_fbx_path(path)) {
+        importer.SetPropertyBool(AI_CONFIG_IMPORT_FBX_READ_ALL_GEOMETRY_LAYERS, true);
+        importer.SetPropertyBool(AI_CONFIG_IMPORT_FBX_READ_MATERIALS, true);
+        importer.SetPropertyBool(AI_CONFIG_IMPORT_FBX_READ_TEXTURES, true);
+        importer.SetPropertyBool(AI_CONFIG_IMPORT_FBX_READ_ANIMATIONS, false);
+        importer.SetPropertyBool(AI_CONFIG_IMPORT_FBX_READ_LIGHTS, false);
+        importer.SetPropertyBool(AI_CONFIG_IMPORT_FBX_READ_CAMERAS, false);
+    }
+}
+
+bool read_external_texture_file(const boost::filesystem::path& path, TextureImage& out)
+{
+    boost::nowide::ifstream file(path.string(), std::ios::binary | std::ios::ate);
+    if (!file.is_open())
+        return false;
+
+    const std::streamoff size = file.tellg();
+    if (size <= 0)
+        return false;
+    if (static_cast<uintmax_t>(size) > static_cast<uintmax_t>(std::numeric_limits<size_t>::max()))
+        return false;
+
+    file.seekg(0);
+    out.width = -1;
+    out.height = -1;
+    out.channels = 0;
+    out.data.resize(static_cast<size_t>(size));
+    file.read(reinterpret_cast<char*>(out.data.data()), size);
+    if (!file && !file.eof()) {
+        out.data.clear();
+        return false;
+    }
+    return true;
+}
+
+bool read_embedded_texture(const aiTexture& texture, TextureImage& out)
+{
+    out.data.clear();
+    if (texture.mHeight == 0) {
+        if (texture.mWidth == 0)
+            return false;
+        out.width = -1;
+        out.height = -1;
+        out.channels = 0;
+        out.data.assign(
+            reinterpret_cast<const unsigned char*>(texture.pcData),
+            reinterpret_cast<const unsigned char*>(texture.pcData) + texture.mWidth);
+        return !out.data.empty();
+    }
+
+    if (texture.mWidth == 0 || texture.mHeight == 0)
+        return false;
+    if (texture.mWidth > static_cast<unsigned int>(std::numeric_limits<int>::max()) ||
+        texture.mHeight > static_cast<unsigned int>(std::numeric_limits<int>::max())) {
+        return false;
+    }
+    const size_t width = static_cast<size_t>(texture.mWidth);
+    const size_t height = static_cast<size_t>(texture.mHeight);
+    if (width > std::numeric_limits<size_t>::max() / height ||
+        width * height > std::numeric_limits<size_t>::max() / 4) {
+        return false;
+    }
+
+    out.width = static_cast<int>(texture.mWidth);
+    out.height = static_cast<int>(texture.mHeight);
+    out.channels = 4;
+    const size_t pixel_count = width * height;
+    out.data.resize(pixel_count * 4);
+    for (size_t i = 0; i < pixel_count; ++i) {
+        const aiTexel& texel = texture.pcData[i];
+        out.data[i * 4 + 0] = texel.r;
+        out.data[i * 4 + 1] = texel.g;
+        out.data[i * 4 + 2] = texel.b;
+        out.data[i * 4 + 3] = texel.a;
+    }
+    return !out.data.empty();
+}
+
+bool get_material_texture(const aiMaterial& material, aiString& texture_path)
+{
+    if (material.GetTextureCount(aiTextureType_DIFFUSE) > 0 &&
+        material.GetTexture(aiTextureType_DIFFUSE, 0, &texture_path) == AI_SUCCESS) {
+        return true;
+    }
+
+    if (material.GetTextureCount(aiTextureType_BASE_COLOR) > 0 &&
+        material.GetTexture(aiTextureType_BASE_COLOR, 0, &texture_path) == AI_SUCCESS) {
+        return true;
+    }
+
+    return false;
+}
+
+std::array<float, 4> get_material_color(const aiMaterial& material)
+{
+    aiColor4D color(1.f, 1.f, 1.f, 1.f);
+    if (material.Get(AI_MATKEY_BASE_COLOR, color) == AI_SUCCESS)
+        return {color.r, color.g, color.b, color.a};
+    if (material.Get(AI_MATKEY_COLOR_DIFFUSE, color) == AI_SUCCESS)
+        return {color.r, color.g, color.b, color.a};
+    return {1.f, 1.f, 1.f, 1.f};
+}
+
+bool collect_mesh(const aiMesh& mesh, size_t& vertex_offset, TexturedMesh& out, std::string& error)
+{
+    if (mesh.mNumVertices > static_cast<size_t>(std::numeric_limits<int>::max()) - vertex_offset) {
+        error = "Assimp mesh has too many vertices for TexturedMesh indices";
+        return false;
+    }
+
+    for (unsigned int i = 0; i < mesh.mNumVertices; ++i) {
+        const aiVector3D& v = mesh.mVertices[i];
+        out.vertices.push_back({v.x, v.y, v.z});
+
+        if (mesh.HasTextureCoords(0)) {
+            const aiVector3D& uv = mesh.mTextureCoords[0][i];
+            out.uvs.push_back({uv.x, uv.y});
+        } else {
+            out.uvs.push_back({0.f, 0.f});
+        }
+    }
+
+    const int material_index = static_cast<int>(mesh.mMaterialIndex);
+    for (unsigned int i = 0; i < mesh.mNumFaces; ++i) {
+        const aiFace& face = mesh.mFaces[i];
+        if (face.mNumIndices != 3)
+            continue;
+        if (face.mIndices[0] >= mesh.mNumVertices ||
+            face.mIndices[1] >= mesh.mNumVertices ||
+            face.mIndices[2] >= mesh.mNumVertices) {
+            error = "Assimp mesh face index is out of bounds";
+            return false;
+        }
+        out.indices.push_back({
+            static_cast<int>(static_cast<size_t>(face.mIndices[0]) + vertex_offset),
+            static_cast<int>(static_cast<size_t>(face.mIndices[1]) + vertex_offset),
+            static_cast<int>(static_cast<size_t>(face.mIndices[2]) + vertex_offset)});
+        out.material_ids.push_back(material_index);
+    }
+
+    vertex_offset += mesh.mNumVertices;
+    return true;
+}
+
+void collect_materials(const aiScene& scene, const boost::filesystem::path& base_dir, TexturedMesh& out)
+{
+    out.material_texture_map.assign(scene.mNumMaterials, -1);
+    out.material_colors.assign(scene.mNumMaterials, {1.f, 1.f, 1.f, 1.f});
+
+    for (unsigned int material_index = 0; material_index < scene.mNumMaterials; ++material_index) {
+        const aiMaterial* material = scene.mMaterials[material_index];
+        if (!material)
+            continue;
+
+        out.material_colors[material_index] = get_material_color(*material);
+
+        aiString texture_path;
+        if (!get_material_texture(*material, texture_path))
+            continue;
+
+        TextureImage image;
+        const aiTexture* embedded_texture = scene.GetEmbeddedTexture(texture_path.C_Str());
+        if (embedded_texture) {
+            if (!read_embedded_texture(*embedded_texture, image))
+                continue;
+        } else {
+            const boost::filesystem::path resolved = resource_path::resolve_external_resource_path(
+                base_dir, texture_path.C_Str(), "Assimp texture");
+            if (resolved.empty()) {
+                BOOST_LOG_TRIVIAL(warning) << "AssimpImport: texture file not found: "
+                                           << texture_path.C_Str();
+                continue;
+            }
+            if (!read_external_texture_file(resolved, image)) {
+                BOOST_LOG_TRIVIAL(warning) << "AssimpImport: failed to read texture: "
+                                           << resolved;
+                continue;
+            }
+        }
+
+        out.material_texture_map[material_index] = static_cast<int>(out.textures.size());
+        out.textures.push_back(std::move(image));
+    }
+}
+
+std::string scene_failure_summary(const std::string& path, const char* assimp_error)
+{
+    std::ostringstream ss;
+    ss << "Assimp failed to import " << path;
+    if (assimp_error && assimp_error[0] != '\0')
+        ss << ": " << assimp_error;
+    return ss.str();
+}
+
+} // namespace
+
+bool load_assimp_textured_model(const std::string& path, TexturedMesh& out, std::string* error_message)
+{
+    clear_textured_mesh(out);
+
+    Assimp::Importer importer;
+    const unsigned int flags = assimp_import_flags(path);
+    configure_importer(importer, path, flags);
+
+    const aiScene* scene = importer.ReadFile(path, flags);
+    if (!scene || (scene->mFlags & AI_SCENE_FLAGS_INCOMPLETE) || !scene->mRootNode) {
+        const std::string message = scene_failure_summary(path, importer.GetErrorString());
+        BOOST_LOG_TRIVIAL(error) << "AssimpImport: " << message;
+        set_error_message(error_message, message);
+        return false;
+    }
+
+    if (scene->mNumMeshes == 0) {
+        const std::string message = "Assimp scene has no meshes: " + path;
+        BOOST_LOG_TRIVIAL(error) << "AssimpImport: " << message;
+        set_error_message(error_message, message);
+        return false;
+    }
+
+    size_t vertex_offset = 0;
+    for (unsigned int mesh_index = 0; mesh_index < scene->mNumMeshes; ++mesh_index) {
+        const aiMesh* mesh = scene->mMeshes[mesh_index];
+        if (!mesh || !mesh->HasPositions())
+            continue;
+        std::string mesh_error;
+        if (!collect_mesh(*mesh, vertex_offset, out, mesh_error)) {
+            const std::string message = mesh_error + ": " + path;
+            BOOST_LOG_TRIVIAL(error) << "AssimpImport: " << message;
+            set_error_message(error_message, message);
+            clear_textured_mesh(out);
+            return false;
+        }
+    }
+
+    if (out.vertices.empty() || out.indices.empty()) {
+        const std::string message = "Assimp extracted no valid triangles: " + path;
+        BOOST_LOG_TRIVIAL(error) << "AssimpImport: " << message;
+        set_error_message(error_message, message);
+        clear_textured_mesh(out);
+        return false;
+    }
+
+    collect_materials(*scene, boost::filesystem::path(path).parent_path(), out);
+
+    BOOST_LOG_TRIVIAL(info) << "AssimpImport: loaded " << out.vertices.size()
+                            << " vertices, " << out.indices.size()
+                            << " triangles, " << out.textures.size()
+                            << " textures from " << path;
+    return true;
+}
+
+} // namespace Slic3r

src/libslic3r/Format/AssimpImport.hpp

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <string>
+
+namespace Slic3r {
+
+struct TexturedMesh;
+
+bool load_assimp_textured_model(const std::string& path, TexturedMesh& out, std::string* error_message = nullptr);
+
+} // namespace Slic3r

src/libslic3r/Model.cpp

@@ -2,6 +2,7 @@
 #include "libslic3r.h"
 #include "BuildVolume.hpp"
 #include "TexturePainting.hpp"
+#include "Format/AssimpImport.hpp"
 #include "ClipperUtils.hpp"
 #include "Exception.hpp"
 #include "Model.hpp"
@@ -242,6 +243,27 @@ _finished:
 // BBS: add part plate related logic
 // BBS: backup & restore
 // Loading model from a file, it may be a simple geometry file as STL or OBJ, however it may be a project file as well.
+// Build a plain geometry ModelObject from a textured mesh. The texture itself is carried
+// separately on Model::texture_mesh and consumed by the texture import dialog.
+static void add_textured_mesh_to_model(Model& model, const TexturedMesh& tex_mesh, const std::string& input_file)
+{
+    std::string object_name = boost::filesystem::path(input_file).filename().string();
+
+    indexed_triangle_set its;
+    its.vertices.resize(tex_mesh.vertices.size());
+    for (size_t i = 0; i < tex_mesh.vertices.size(); ++i)
+        its.vertices[i] = Vec3f(tex_mesh.vertices[i][0], tex_mesh.vertices[i][1], tex_mesh.vertices[i][2]);
+    its.indices.resize(tex_mesh.indices.size());
+    for (size_t i = 0; i < tex_mesh.indices.size(); ++i)
+        its.indices[i] = Vec3i32(tex_mesh.indices[i][0], tex_mesh.indices[i][1], tex_mesh.indices[i][2]);
+
+    its_merge_vertices(its);
+    its_remove_degenerate_faces(its);
+    its_compactify_vertices(its);
+
+    model.add_object(object_name.c_str(), input_file.c_str(), std::move(TriangleMesh(std::move(its))));
+}
+
 Model Model::read_from_file(const std::string&                                  input_file,
                             DynamicPrintConfig*                                 config,
                             ConfigSubstitutionContext*                          config_substitutions,
@@ -325,6 +347,23 @@ Model Model::read_from_file(const std::string&
             }*/
         }
     }
+    else if (boost::algorithm::iends_with(input_file, ".glb") ||
+             boost::algorithm::iends_with(input_file, ".gltf") ||
+             boost::algorithm::iends_with(input_file, ".fbx")) {
+        // These formats always carry material/texture data, so they go through the textured
+        // import path: the geometry becomes a normal object and the texture is handed to the
+        // texture-to-color dialog via Model::texture_mesh.
+        auto tex_mesh = std::make_shared<TexturedMesh>();
+        result = load_assimp_textured_model(input_file, *tex_mesh, &message);
+        if (result) {
+            model.texture_mesh = tex_mesh;
+            add_textured_mesh_to_model(model, *tex_mesh, input_file);
+        } else if (!message.empty()) {
+            BOOST_LOG_TRIVIAL(error) << "Assimp: failed to load model: " << message
+                                     << ", path=" << input_file;
+            message = _L("The file format is incompatible and cannot be parsed.");
+        }
+    }
     else if (boost::algorithm::iends_with(input_file, ".svg"))
         result = load_svg(input_file.c_str(), &model, message);
     //BBS: remove the old .amf.xml files

src/slic3r/GUI/GUI_App.cpp

@@ -521,10 +521,10 @@ static const FileWildcards file_wildcards_by_type[FT_SIZE] = {
     /* FT_GCODE */   { L("G-code files"),    { ".gcode"sv} },
 #ifdef __APPLE__
     /* FT_MODEL */
-    {L("Supported files"), {".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}},
+    {L("Supported files"), {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv, ".gltf"sv, ".glb"sv, ".fbx"sv, ".usd"sv, ".usda"sv, ".usdc"sv, ".usdz"sv, ".abc"sv, ".ply"sv, ".drc"sv}},
 #else
     /* FT_MODEL */
-    {L("Supported files"), {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv, ".drc"sv}},
+    {L("Supported files"), {".3mf"sv, ".stl"sv, ".oltp"sv, ".stp"sv, ".step"sv, ".svg"sv, ".amf"sv, ".obj"sv, ".gltf"sv, ".glb"sv, ".fbx"sv, ".drc"sv}},
 #endif
     /* FT_ZIP */     { L("ZIP files"),       { ".zip"sv } },
     /* FT_PROJECT */ { L("Project files"),   { ".3mf"sv} },