# Notes by Charles Duffy -- # # - The new version of OpenMP does not allow outside variables to be referenced # *at all* without an explicit declaration of how they're supposed to be # handled. Thus, this was an outright build failure beforehand. The new # pragmas copy the initial value from the outer scope into each parallel # thread. Since these variables are all constant within the loops, this is # clearly correct. (Not sure it's *optimal*, but quite sure it isn't # *wrong*). # - Upstream has been contacted -- I'm a Lulzbot customer with an active # support contract and sent them the patch. That said, they're in the middle # of some major corporate churn (sold themselves out of near-bankruptcy to an # out-of-state business entity formed as a holding company; moved to that # state; have been slowly restaffing after), so a response may take a while. # - The patch is purely my own work. --- curaengine/src/support.cpp.orig 2020-03-28 10:38:01.953912363 -0500 +++ curaengine/src/support.cpp 2020-03-28 10:45:28.999791908 -0500 @@ -854,7 +854,7 @@ const double tan_angle = tan(angle) - 0.01; // the XY-component of the supportAngle xy_disallowed_per_layer[0] = storage.getLayerOutlines(0, false).offset(xy_distance); // for all other layers (of non support meshes) compute the overhang area and possibly use that when calculating the support disallowed area - #pragma omp parallel for default(none) shared(xy_disallowed_per_layer, storage, mesh) schedule(dynamic) + #pragma omp parallel for default(none) firstprivate(layer_count, is_support_mesh_place_holder, use_xy_distance_overhang, z_distance_top, tan_angle, xy_distance, xy_distance_overhang) shared(xy_disallowed_per_layer, storage, mesh) schedule(dynamic) for (unsigned int layer_idx = 1; layer_idx < layer_count; layer_idx++) { Polygons outlines = storage.getLayerOutlines(layer_idx, false); @@ -1054,7 +1054,7 @@ const int max_checking_layer_idx = std::min(static_cast(storage.support.supportLayers.size()) , static_cast(layer_count - (layer_z_distance_top - 1))); const size_t max_checking_idx_size_t = std::max(0, max_checking_layer_idx); -#pragma omp parallel for default(none) shared(support_areas, storage) schedule(dynamic) +#pragma omp parallel for default(none) firstprivate(max_checking_idx_size_t, layer_z_distance_top) shared(support_areas, storage) schedule(dynamic) for (size_t layer_idx = 0; layer_idx < max_checking_idx_size_t; layer_idx++) { support_areas[layer_idx] = support_areas[layer_idx].difference(storage.getLayerOutlines(layer_idx + layer_z_distance_top - 1, false)); --- curaengine/src/layerPart.cpp.orig 2020-03-28 10:36:40.381023651 -0500 +++ curaengine/src/layerPart.cpp 2020-03-28 10:39:54.584140465 -0500 @@ -49,7 +49,7 @@ { const auto total_layers = slicer->layers.size(); assert(mesh.layers.size() == total_layers); -#pragma omp parallel for default(none) shared(mesh, slicer) schedule(dynamic) +#pragma omp parallel for default(none) firstprivate(total_layers) shared(mesh, slicer) schedule(dynamic) for (unsigned int layer_nr = 0; layer_nr < total_layers; layer_nr++) { SliceLayer& layer_storage = mesh.layers[layer_nr];