Fixing broken SLA slicing: SPE-984

2 files changed, 6 insertions, 7 deletions

diff --git a/src/libslic3r/SLA/SLABasePool.cpp b/src/libslic3r/SLA/SLABasePool.cpp
index 04cbd7824..b1fbec839 100644
--- a/src/libslic3r/SLA/SLABasePool.cpp
+++ b/src/libslic3r/SLA/SLABasePool.cpp
@@ -510,9 +510,9 @@ ExPolygons concave_hull(const ExPolygons& polys, double max_dist_mm = 50,
 void base_plate(const TriangleMesh &mesh, ExPolygons &output, float h,
                 float layerh, ThrowOnCancel thrfn)
 {
-    TriangleMesh m = mesh;
-    m.require_shared_vertices(); // TriangleMeshSlicer needs this
-    TriangleMeshSlicer slicer(&m);
+    if (mesh.empty()) return;
+
+    TriangleMeshSlicer slicer(&mesh);
 
     auto bb = mesh.bounding_box();
     float gnd = float(bb.min(Z));
diff --git a/src/libslic3r/SLA/SLASupportTree.cpp b/src/libslic3r/SLA/SLASupportTree.cpp
index ae033c62f..1f7ef07cb 100644
--- a/src/libslic3r/SLA/SLASupportTree.cpp
+++ b/src/libslic3r/SLA/SLASupportTree.cpp
@@ -808,7 +808,6 @@ public:
             merged.merge(bs.mesh);
         }
 
-
         if(m_ctl.stopcondition()) {
             // In case of failure we have to return an empty mesh
             meshcache = TriangleMesh();
@@ -819,7 +818,7 @@ public:
 
         // The mesh will be passed by const-pointer to TriangleMeshSlicer,
         // which will need this.
-        meshcache.require_shared_vertices();
+        if (!meshcache.empty()) meshcache.require_shared_vertices();
 
         // TODO: Is this necessary?
         //meshcache.repair();
@@ -2245,7 +2244,7 @@ SlicedSupports SLASupportTree::slice(float layerh, float init_layerh) const
 
     TriangleMesh fullmesh = m_impl->merged_mesh();
     fullmesh.merge(get_pad());
-    fullmesh.require_shared_vertices(); // TriangleMeshSlicer needs this
+    if (!fullmesh.empty()) fullmesh.require_shared_vertices();
     TriangleMeshSlicer slicer(&fullmesh);
     SlicedSupports ret;
     slicer.slice(heights, 0.f, &ret, get().ctl().cancelfn);
@@ -2258,7 +2257,7 @@ SlicedSupports SLASupportTree::slice(const std::vector<float> &heights,
 {
     TriangleMesh fullmesh = m_impl->merged_mesh();
     fullmesh.merge(get_pad());
-    fullmesh.require_shared_vertices(); // TriangleMeshSlicer needs this
+    if (!fullmesh.empty()) fullmesh.require_shared_vertices();
     TriangleMeshSlicer slicer(&fullmesh);
     SlicedSupports ret;
     slicer.slice(heights, cr, &ret, get().ctl().cancelfn);