Merge pull request #5146 from assimp/kimkulling/dxf_handling_for_invisible_faces_issue-2036

Add handling for negative indices.

code/AssetLib/DXF/DXFLoader.cpp

@@ -88,6 +88,7 @@ static aiColor4D g_aclrDxfIndexColors[] = {
     aiColor4D (1.0f, 1.0f, 1.0f, 1.0f), // white
     aiColor4D (0.6f, 0.0f, 1.0f, 1.0f)  // violet
 };
+
 #define AI_DXF_NUM_INDEX_COLORS (sizeof(g_aclrDxfIndexColors)/sizeof(g_aclrDxfIndexColors[0]))
 #define AI_DXF_ENTITIES_MAGIC_BLOCK "$ASSIMP_ENTITIES_MAGIC"
 
@@ -109,14 +110,6 @@ static const aiImporterDesc desc = {
     "dxf"
 };
 
-// ------------------------------------------------------------------------------------------------
-// Constructor to be privately used by Importer
-DXFImporter::DXFImporter() = default;
-
-// ------------------------------------------------------------------------------------------------
-// Destructor, private as well
-DXFImporter::~DXFImporter() = default;
-
 // ------------------------------------------------------------------------------------------------
 // Returns whether the class can handle the format of the given file.
 bool DXFImporter::CanRead( const std::string& filename, IOSystem* pIOHandler, bool /*checkSig*/ ) const {
@@ -229,7 +222,7 @@ void DXFImporter::ConvertMeshes(aiScene* pScene, DXF::FileData& output) {
         ASSIMP_LOG_VERBOSE_DEBUG("DXF: Unexpanded polycount is ", icount, ", vertex count is ", vcount);
     }
 
-    if (! output.blocks.size()  ) {
+    if (output.blocks.empty()) {
         throw DeadlyImportError("DXF: no data blocks loaded");
     }
 
@@ -587,10 +580,11 @@ void DXFImporter::ParseInsertion(DXF::LineReader& reader, DXF::FileData& output)
     }
 }
 
-#define DXF_POLYLINE_FLAG_CLOSED        0x1
+static constexpr unsigned int DXF_POLYLINE_FLAG_CLOSED = 0x1;
-#define DXF_POLYLINE_FLAG_3D_POLYLINE   0x8
+// Currently unused
-#define DXF_POLYLINE_FLAG_3D_POLYMESH   0x10
+//static constexpr unsigned int DXF_POLYLINE_FLAG_3D_POLYLINE = 0x8;
-#define DXF_POLYLINE_FLAG_POLYFACEMESH  0x40
+//static constexpr unsigned int DXF_POLYLINE_FLAG_3D_POLYMESH = 0x10;
+static constexpr unsigned int DXF_POLYLINE_FLAG_POLYFACEMESH = 0x40;
 
 // ------------------------------------------------------------------------------------------------
 void DXFImporter::ParsePolyLine(DXF::LineReader& reader, DXF::FileData& output) {
@@ -639,12 +633,6 @@ void DXFImporter::ParsePolyLine(DXF::LineReader& reader, DXF::FileData& output)
         reader++;
     }
 
-    //if (!(line.flags & DXF_POLYLINE_FLAG_POLYFACEMESH))   {
-    //  DefaultLogger::get()->warn((Formatter::format("DXF: polyline not currently supported: "),line.flags));
-    //  output.blocks.back().lines.pop_back();
-    //  return;
-    //}
-
     if (vguess && line.positions.size() != vguess) {
         ASSIMP_LOG_WARN("DXF: unexpected vertex count in polymesh: ",
             line.positions.size(),", expected ", vguess );
@@ -734,12 +722,18 @@ void DXFImporter::ParsePolyLineVertex(DXF::LineReader& reader, DXF::PolyLine& li
         case 71:
         case 72:
         case 73:
-        case 74:
+        case 74: {
                 if (cnti == 4) {
                     ASSIMP_LOG_WARN("DXF: more than 4 indices per face not supported; ignoring");
                     break;
                 }
-            indices[cnti++] = reader.ValueAsUnsignedInt();
+                const int index = reader.ValueAsSignedInt();
+                if (index >= 0) {
+                    indices[cnti++] = static_cast<unsigned int>(index);
+                } else {
+                    ASSIMP_LOG_WARN("DXF: Skip invisible face.");
+                }
+            }
             break;
 
         // color
@@ -777,8 +771,7 @@ void DXFImporter::ParsePolyLineVertex(DXF::LineReader& reader, DXF::PolyLine& li
 }
 
 // ------------------------------------------------------------------------------------------------
-void DXFImporter::Parse3DFace(DXF::LineReader& reader, DXF::FileData& output)
+void DXFImporter::Parse3DFace(DXF::LineReader& reader, DXF::FileData& output) {
-{
     // (note) this is also used for for parsing line entities, so we
     // must handle the vertex_count == 2 case as well.
 
@@ -795,8 +788,7 @@ void DXFImporter::Parse3DFace(DXF::LineReader& reader, DXF::FileData& output)
         if (reader.GroupCode() == 0) {
             break;
         }
-        switch (reader.GroupCode())
+        switch (reader.GroupCode()) {
-        {
 
         // 8 specifies the layer
         case 8:

code/AssetLib/DXF/DXFLoader.h

@@ -68,8 +68,8 @@ namespace DXF {
  */
 class DXFImporter : public BaseImporter {
 public:
-    DXFImporter();
+    DXFImporter() = default;
-    ~DXFImporter() override;
+    ~DXFImporter() override = default;
 
     // -------------------------------------------------------------------
     /** Returns whether the class can handle the format of the given file.

contrib/zlib/CMakeLists.txt

@@ -76,15 +76,7 @@ if(MSVC)
     set(CMAKE_DEBUG_POSTFIX "d")
     add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
     add_definitions(-D_CRT_NONSTDC_NO_DEPRECATE)
-    if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" ) # clang-cl
-        SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-deprecated-non-prototype")
-    endif()
-
     include_directories(${CMAKE_CURRENT_SOURCE_DIR})
-else()
-    if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" ) # clang-cl
-        SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-deprecated-non-prototype")
-    endif()
 endif()
 
 if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)