Draw Preview Segments With 16-Bit Indices

The segment draw switched to an element buffer of 8-bit indices. GCN 1/2
GPUs cannot read 8-bit indices in hardware, so the driver converts them,
and on a Mac Pro 2013 FirePro under Windows Boot Camp the toolpaths come
out as scattered spikes. 16-bit indices are supported everywhere and keep
the eight shader runs per segment.

src/libslic3r/Format/bbs_3mf.cpp

@@ -1729,8 +1729,8 @@ void PlateData::parse_filament_info(GCodeProcessorResult *result)
             //plate->pattern_file = it->second->pattern_file;
             plate->no_light_thumbnail_file = it->second->no_light_thumbnail_file;
             plate->top_file = it->second->top_file;
-            plate->pick_file = it->second->pick_file.empty();
-            plate->pattern_bbox_file = it->second->pattern_bbox_file.empty();
+            plate->pick_file = it->second->pick_file;
+            plate->pattern_bbox_file = it->second->pattern_bbox_file;
             plate->config = it->second->config;
 
             if (!plate->thumbnail_file.empty())

src/libslic3r/GCode.cpp

@@ -3295,7 +3295,7 @@ void GCode::_do_export(Print& print, GCodeOutputStream &file, ThumbnailsGenerato
     m_is_role_based_fan_on.fill(false);
     m_role_based_fan_marker_layer.fill(-1);
 
-    m_fan_mover.release();
+    m_fan_mover.reset();
     m_ordering_cache.clear();
 
     // Belt printer: initialize belt-specific writer via virtual hook.

src/libvgcode/src/SegmentTemplate.cpp

@@ -21,7 +21,9 @@ namespace libvgcode {
 // the triangles that share it: the shader runs 8 times per segment instead of 24.
 static constexpr const std::array<uint8_t, 8> VERTEX_DATA = { 0, 1, 2, 3, 4, 5, 6, 7 };
 
-static constexpr const std::array<uint8_t, 24> INDEX_DATA = {
+// 16-bit indices: GCN 1/2 GPUs have no 8-bit index support, and some of their drivers
+// emulate it wrongly in instanced draws.
+static constexpr const std::array<uint16_t, 24> INDEX_DATA = {
     0, 1, 2, // front spike
     0, 2, 3, // front spike
     0, 3, 4, // right/bottom body 
@@ -37,7 +39,7 @@ void SegmentTemplate::init()
     if (m_vao_id != 0)
         return;
 
-    m_size_in_bytes_gpu += (VERTEX_DATA.size() + INDEX_DATA.size()) * sizeof(uint8_t);
+    m_size_in_bytes_gpu += VERTEX_DATA.size() * sizeof(uint8_t) + INDEX_DATA.size() * sizeof(uint16_t);
 
     int curr_vertex_array;
     glsafe(glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &curr_vertex_array));
@@ -61,7 +63,7 @@ void SegmentTemplate::init()
     // and restored together with the vao.
     glsafe(glGenBuffers(1, &m_ibo_id));
     glsafe(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ibo_id));
-    glsafe(glBufferData(GL_ELEMENT_ARRAY_BUFFER, INDEX_DATA.size() * sizeof(uint8_t), INDEX_DATA.data(), GL_STATIC_DRAW));
+    glsafe(glBufferData(GL_ELEMENT_ARRAY_BUFFER, INDEX_DATA.size() * sizeof(uint16_t), INDEX_DATA.data(), GL_STATIC_DRAW));
 
     glsafe(glBindBuffer(GL_ARRAY_BUFFER, curr_array_buffer));
     glsafe(glBindVertexArray(curr_vertex_array));
@@ -94,7 +96,7 @@ void SegmentTemplate::render(size_t count)
     glsafe(glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &curr_vertex_array));
 
     glsafe(glBindVertexArray(m_vao_id));
-    glsafe(glDrawElementsInstanced(GL_TRIANGLES, static_cast<GLsizei>(INDEX_DATA.size()), GL_UNSIGNED_BYTE,
+    glsafe(glDrawElementsInstanced(GL_TRIANGLES, static_cast<GLsizei>(INDEX_DATA.size()), GL_UNSIGNED_SHORT,
                                    nullptr, static_cast<GLsizei>(count)));
     glsafe(glBindVertexArray(curr_vertex_array));
 }

tests/libslic3r/test_3mf.cpp

@@ -2043,3 +2043,40 @@ TEST_CASE("3MF XML entries declaring more than an int can hold fail to load", "[
         CHECK_FALSE(parser.check_3mf_from_prusa(path));
     }
 }
+
+TEST_CASE("Loading a gcode.3mf from a stream keeps the plate's pick and pattern file paths", "[3mf][Regression]")
+{
+    Model model;
+    REQUIRE(load_stl((std::string(TEST_DATA_DIR) + "/test_3mf/Prusa.stl").c_str(), &model));
+    model.add_default_instances();
+    ScopedTemporaryDir backup_dir("orca_pick");
+    model.set_backup_path(backup_dir.string());
+    DynamicPrintConfig config = DynamicPrintConfig::full_print_config();
+
+    auto plate = std::make_unique<PlateData>();
+    plate->plate_index       = 0;
+    plate->pick_file         = (backup_dir.path() / "pick.png").string();
+    plate->pattern_bbox_file = (backup_dir.path() / "plate.json").string();
+
+    ScopedTemporaryFile temp(".3mf");
+    const std::string   test_file = temp.string();
+    StoreParams store_params;
+    store_params.path   = test_file.c_str();
+    store_params.model  = &model;
+    store_params.config = &config;
+    store_params.plate_data_list.push_back(plate.get());
+    store_params.strategy = SaveStrategy::Zip64 | SaveStrategy::Silence;
+    REQUIRE(store_bbs_3mf(store_params));
+
+    boost::nowide::ifstream in(test_file, std::ios::binary);
+    Model              dst_model;
+    DynamicPrintConfig dst_config;
+    PlateDataPtrs      dst_plates;
+    Semver             file_version;
+    dst_model.set_backup_path(backup_dir.string());
+    REQUIRE(load_gcode_3mf_from_stream(in, &dst_config, &dst_model, &dst_plates, &file_version));
+    REQUIRE(dst_plates.size() == 1);
+    CHECK(dst_plates.front()->pick_file == "Metadata/pick_1.png");
+    CHECK(dst_plates.front()->pattern_bbox_file == "Metadata/plate_1.json");
+    release_PlateData_list(dst_plates);
+}