Add checks for invalid indices in .obj file loading and return 0 instead of...

Add checks for invalid indices in .obj file loading and return 0 instead of crashing when that happens. 
This applies (slightly modified) patch #296 from patchtracker. Thx @mbohnen for report and patch.


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4983 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/COBJMeshFileLoader.cpp

@@ -225,18 +225,25 @@ IAnimatedMesh* COBJMeshFileLoader::createMesh(io::IReadFile* file)
 				// sends the buffer sizes and gets the actual indices
 				// if index not set returns -1
 				s32 Idx[3];
-				Idx[1] = Idx[2] = -1;
+				Idx[0] = Idx[1] = Idx[2] = -1;
 
 				// read in next vertex's data
 				u32 wlength = copyWord(vertexWord, linePtr, WORD_BUFFER_LENGTH, endPtr);
 				// this function will also convert obj's 1-based index to c++'s 0-based index
 				retrieveVertexIndices(vertexWord, Idx, vertexWord+wlength+1, vertexBuffer.size(), textureCoordBuffer.size(), normalsBuffer.size());
-				v.Pos = vertexBuffer[Idx[0]];
-				if ( -1 != Idx[1] )
+				if ( -1 != Idx[0] && Idx[0] < (irr::s32)vertexBuffer.size() )
+					v.Pos = vertexBuffer[Idx[0]];
+				else
+				{
+					os::Printer::log("Invalid vertex index in this line:", wordBuffer.c_str(), ELL_ERROR);
+					delete [] buf;
+					return 0;
+				}
+				if ( -1 != Idx[1] && Idx[1] < (irr::s32)textureCoordBuffer.size() )
 					v.TCoords = textureCoordBuffer[Idx[1]];
 				else
 					v.TCoords.set(0.0f,0.0f);
-				if ( -1 != Idx[2] )
+				if ( -1 != Idx[2] && Idx[2] < (irr::s32)normalsBuffer.size() )
 					v.Normal = normalsBuffer[Idx[2]];
 				else
 				{