Prevent hard crashes on incorrect assimp files (the mesh named object…

… is missing in the nodes hierarchy). Instead look for a likely replacemetn (the first level child of Scene object that has no childrens). Throw content error exception instead of crashing too.
beyond-all-reason · Sep 13, 2023 · b0494c9 · b0494c9
1 parent 3f34c43
commit b0494c9
Show file tree

Hide file tree

Showing 2 changed files with 27 additions and 7 deletions.
diff --git a/rts/Rendering/Models/AssParser.cpp b/rts/Rendering/Models/AssParser.cpp
@@ -313,12 +313,20 @@ void CAssParser::Load(S3DModel& model, const std::string& modelFilePath)
 		std::vector<SPseudoAssPiece> meshPseudoPieces(meshNames.size());
 		auto mppIt = meshPseudoPieces.begin();
 		for (const auto& meshName : meshNames) {
+			aiNode* meshNode = nullptr;
+			meshNode = FindNode(scene, scene->mRootNode, meshName);
 			mppIt->name = meshName;
+			if (!meshNode) {
+				LOG_SL(LOG_SECTION_MODEL, L_ERROR, "An assimp model has invalid pieces hierarchy. Missing a mesh named: \"%s\" in model[\"%s\"] path: %s. Looking for a likely candidate", meshName.c_str(), modelName.c_str(), modelPath.c_str());
+
+				meshNode = FindFallbackNode(scene);
+				if (meshNode && meshNode->mParent)
+					LOG_SL(LOG_SECTION_MODEL, L_WARNING, "Found a likely replacement candidate for mesh \"%s\" - node \"%s\". It might be incorrect!", meshName.c_str(), meshNode->mName.data);
+				else
+					throw content_error("An assimp model has invalid pieces hierarchy. Failed to find suitable replacement.");
+			}
 
-			const auto* meshNode = FindNode(scene, scene->mRootNode, meshName);
-			assert(meshNode && meshNode->mParent);
-
-			std::string parentName(meshNode->mParent->mName.C_Str());
+			std::string const parentName(meshNode->mParent->mName.C_Str());
 			auto* parentPiece = model.FindPiece(parentName);
 			assert(parentPiece);
 			mppIt->parent = parentPiece;
@@ -726,20 +734,31 @@ const std::vector<std::string> CAssParser::GetMeshNames(const aiScene* scene)
 	return meshNames;
 }
 
-const aiNode* CAssParser::FindNode(const aiScene* scene, const aiNode* node, const std::string& name)
+aiNode* CAssParser::FindNode(const aiScene* scene, aiNode* node, const std::string& name)
 {
 	if (std::string(node->mName.C_Str()) == name)
 		return node;
 
 	for (uint32_t ci = 0; ci < node->mNumChildren; ++ci) {
-		const auto* childTargetNode = FindNode(scene, node->mChildren[ci], name);
+		auto* childTargetNode = FindNode(scene, node->mChildren[ci], name);
 		if (childTargetNode)
 			return childTargetNode;
 	}
 
 	return nullptr;
 }
 
+aiNode* CAssParser::FindFallbackNode(const aiScene* scene)
+{
+	for (uint32_t ci = 0; ci < scene->mRootNode->mNumChildren; ++ci) {
+		if (scene->mRootNode->mChildren[ci]->mNumChildren == 0) {
+			return scene->mRootNode->mChildren[ci];
+		}
+	}
+
+	return nullptr;
+}
+
 const std::vector<CMatrix44f> CAssParser::GetMeshBoneMatrices(const aiScene* scene, const S3DModel* model, std::vector<SPseudoAssPiece>& meshPPs)
 {
 	std::vector<CMatrix44f> meshBoneMatrices;

diff --git a/rts/Rendering/Models/AssParser.h b/rts/Rendering/Models/AssParser.h
@@ -98,7 +98,8 @@ class CAssParser: public IModelParser
 
 	static const std::vector<std::string> GetBoneNames(const aiScene* scene);
 	static const std::vector<std::string> GetMeshNames(const aiScene* scene);
-	static const aiNode* FindNode(const aiScene* scene, const aiNode* node, const std::string& name);
+	static aiNode* FindNode(const aiScene* scene, aiNode* node, const std::string& name);
+	static aiNode* FindFallbackNode(const aiScene* scene);
 	static const std::vector<CMatrix44f> GetMeshBoneMatrices(
 		const aiScene* scene,
 		const S3DModel* model,