Merge branch 'nullroots' into 'master'

Improve null root handling

Closes #5963

See merge request OpenMW/openmw!818

components/nif/niffile.cpp

@@ -322,7 +322,7 @@ void NIFFile::parse(Files::IStreamPtr stream)
         else
         {
             roots[i] = nullptr;
-            warn("Null Root found");
+            warn("Root " + std::to_string(i + 1) + " does not point to a record: index " + std::to_string(idx));
         }
     }
 

components/nifbullet/bulletnifloader.cpp

@@ -121,12 +121,14 @@ osg::ref_ptr<Resource::BulletShape> BulletNifLoader::load(const Nif::File& nif)
     mAvoidStaticMesh.reset();
 
     const size_t numRoots = nif.numRoots();
-    std::vector<Nif::Node*> roots;
+    std::vector<const Nif::Node*> roots;
     for (size_t i = 0; i < numRoots; ++i)
     {
-        Nif::Record* r = nif.getRoot(i);
-        assert(r != nullptr);
-        if (Nif::Node* node = dynamic_cast<Nif::Node*>(r))
+        const Nif::Record* r = nif.getRoot(i);
+        if (!r)
+            continue;
+        const Nif::Node* node = dynamic_cast<const Nif::Node*>(r);
+        if (node)
             roots.emplace_back(node);
     }
     const std::string filename = nif.getFilename();

components/nifosg/nifloader.cpp

@@ -254,8 +254,7 @@ namespace NifOsg
             for (size_t i = 0; i < numRoots; ++i)
             {
                 const Nif::Record *r = nif->getRoot(i);
-                assert(r != nullptr);
-                if (r->recType == Nif::RC_NiSequenceStreamHelper)
+                if (r && r->recType == Nif::RC_NiSequenceStreamHelper)
                 {
                     seq = static_cast<const Nif::NiSequenceStreamHelper*>(r);
                     break;
@@ -312,7 +311,10 @@ namespace NifOsg
             for (size_t i = 0; i < numRoots; ++i)
             {
                 const Nif::Record* r = nif->getRoot(i);
-                if (const Nif::Node* nifNode = dynamic_cast<const Nif::Node*>(r))
+                if (!r)
+                    continue;
+                const Nif::Node* nifNode = dynamic_cast<const Nif::Node*>(r);
+                if (nifNode)
                     roots.emplace_back(nifNode);
             }
             if (roots.empty())