Change API and handle no-mtl-file case correctly. Fixes #58.

examples/obj_sticher/obj_sticher.cc

@@ -86,9 +86,12 @@ main(
   for (int i = 0; i < num_objfiles; i++) {
     std::cout << "Loading " << argv[i+1] << " ... " << std::flush;
     
-    std::string err = tinyobj::LoadObj(shapes[i], materials[i], argv[i+1]);
+    std::string err;
+    bool ret = tinyobj::LoadObj(shapes[i], materials[i], err, argv[i+1]);
     if (!err.empty()) {
       std::cerr << err << std::endl;
+    }
+    if (!ret) {
       exit(1);
     }
 

missing_material_file.obj

@@ -0,0 +1,145 @@
+# cornell_box.obj and cornell_box.mtl are grabbed from Intel's embree project.
+# original cornell box data
+  # comment
+
+# empty line including some space
+   
+
+#mtllib no_material.mtl
+
+o floor
+usemtl white
+v 552.8 0.0   0.0
+v 0.0   0.0   0.0
+v 0.0   0.0 559.2
+v 549.6 0.0 559.2
+
+v 130.0 0.0  65.0
+v  82.0 0.0 225.0
+v 240.0 0.0 272.0
+v 290.0 0.0 114.0
+
+v 423.0 0.0 247.0
+v 265.0 0.0 296.0
+v 314.0 0.0 456.0
+v 472.0 0.0 406.0
+
+f 1 2 3 4 
+f 8 7 6 5
+f 12 11 10 9
+
+o light
+usemtl light
+v 343.0 548.0 227.0
+v 343.0 548.0 332.0
+v 213.0 548.0 332.0
+v 213.0 548.0 227.0
+f -4 -3 -2 -1
+
+o ceiling
+usemtl white
+v 556.0 548.8 0.0
+v 556.0 548.8 559.2
+v 0.0 548.8 559.2
+v 0.0 548.8 0.0
+f -4 -3 -2 -1
+
+o back_wall
+usemtl white
+v 549.6   0.0 559.2
+v 0.0   0.0 559.2
+v 0.0 548.8 559.2
+v 556.0 548.8 559.2
+f -4 -3 -2 -1
+
+o front_wall
+usemtl blue
+v 549.6   0.0 0
+v 0.0   0.0 0
+v 0.0 548.8 0
+v 556.0 548.8 0
+#f -1 -2 -3 -4
+
+o green_wall
+usemtl green
+v    0.0   0.0 559.2
+v    0.0   0.0   0.0
+v    0.0 548.8   0.0
+v    0.0 548.8 559.2
+f -4 -3 -2 -1
+
+o red_wall
+usemtl red
+v    552.8   0.0   0.0
+v    549.6   0.0 559.2
+v    556.0 548.8 559.2
+v    556.0 548.8   0.0
+f -4 -3 -2 -1
+
+o short_block
+usemtl white
+
+v    130.0 165.0  65.0
+v     82.0 165.0 225.0
+v    240.0 165.0 272.0
+v    290.0 165.0 114.0
+f -4 -3 -2 -1
+
+v    290.0   0.0 114.0
+v    290.0 165.0 114.0
+v    240.0 165.0 272.0
+v    240.0   0.0 272.0
+f -4 -3 -2 -1
+
+v    130.0   0.0  65.0
+v    130.0 165.0  65.0
+v    290.0 165.0 114.0
+v    290.0   0.0 114.0
+f -4 -3 -2 -1
+
+v     82.0   0.0 225.0
+v     82.0 165.0 225.0
+v    130.0 165.0  65.0
+v    130.0   0.0  65.0
+f -4 -3 -2 -1
+
+v    240.0   0.0 272.0
+v    240.0 165.0 272.0
+v     82.0 165.0 225.0
+v     82.0   0.0 225.0
+f -4 -3 -2 -1
+
+o tall_block
+usemtl white
+
+v    423.0 330.0 247.0
+v    265.0 330.0 296.0
+v    314.0 330.0 456.0
+v    472.0 330.0 406.0
+f -4 -3 -2 -1
+
+usemtl white
+v    423.0   0.0 247.0
+v    423.0 330.0 247.0
+v    472.0 330.0 406.0
+v    472.0   0.0 406.0
+f -4 -3 -2 -1
+
+v    472.0   0.0 406.0
+v    472.0 330.0 406.0
+v    314.0 330.0 456.0
+v    314.0   0.0 456.0
+f -4 -3 -2 -1
+
+v    314.0   0.0 456.0
+v    314.0 330.0 456.0
+v    265.0 330.0 296.0
+v    265.0   0.0 296.0
+f -4 -3 -2 -1
+
+v    265.0   0.0 296.0
+v    265.0 330.0 296.0
+v    423.0 330.0 247.0
+v    423.0   0.0 247.0
+f -4 -3 -2 -1
+

no_material.obj

@@ -0,0 +1,133 @@
+# cornell_box.obj and cornell_box.mtl are grabbed from Intel's embree project.
+# original cornell box data
+  # comment
+
+# empty line including some space
+   
+
+o floor
+v 552.8 0.0   0.0
+v 0.0   0.0   0.0
+v 0.0   0.0 559.2
+v 549.6 0.0 559.2
+
+v 130.0 0.0  65.0
+v  82.0 0.0 225.0
+v 240.0 0.0 272.0
+v 290.0 0.0 114.0
+
+v 423.0 0.0 247.0
+v 265.0 0.0 296.0
+v 314.0 0.0 456.0
+v 472.0 0.0 406.0
+
+f 1 2 3 4 
+f 8 7 6 5
+f 12 11 10 9
+
+o light
+v 343.0 548.0 227.0
+v 343.0 548.0 332.0
+v 213.0 548.0 332.0
+v 213.0 548.0 227.0
+f -4 -3 -2 -1
+
+o ceiling
+v 556.0 548.8 0.0
+v 556.0 548.8 559.2
+v 0.0 548.8 559.2
+v 0.0 548.8 0.0
+f -4 -3 -2 -1
+
+o back_wall
+v 549.6   0.0 559.2
+v 0.0   0.0 559.2
+v 0.0 548.8 559.2
+v 556.0 548.8 559.2
+f -4 -3 -2 -1
+
+o front_wall
+v 549.6   0.0 0
+v 0.0   0.0 0
+v 0.0 548.8 0
+v 556.0 548.8 0
+#f -1 -2 -3 -4
+
+o green_wall
+v    0.0   0.0 559.2
+v    0.0   0.0   0.0
+v    0.0 548.8   0.0
+v    0.0 548.8 559.2
+f -4 -3 -2 -1
+
+o red_wall
+v    552.8   0.0   0.0
+v    549.6   0.0 559.2
+v    556.0 548.8 559.2
+v    556.0 548.8   0.0
+f -4 -3 -2 -1
+
+o short_block
+
+v    130.0 165.0  65.0
+v     82.0 165.0 225.0
+v    240.0 165.0 272.0
+v    290.0 165.0 114.0
+f -4 -3 -2 -1
+
+v    290.0   0.0 114.0
+v    290.0 165.0 114.0
+v    240.0 165.0 272.0
+v    240.0   0.0 272.0
+f -4 -3 -2 -1
+
+v    130.0   0.0  65.0
+v    130.0 165.0  65.0
+v    290.0 165.0 114.0
+v    290.0   0.0 114.0
+f -4 -3 -2 -1
+
+v     82.0   0.0 225.0
+v     82.0 165.0 225.0
+v    130.0 165.0  65.0
+v    130.0   0.0  65.0
+f -4 -3 -2 -1
+
+v    240.0   0.0 272.0
+v    240.0 165.0 272.0
+v     82.0 165.0 225.0
+v     82.0   0.0 225.0
+f -4 -3 -2 -1
+
+o tall_block
+
+v    423.0 330.0 247.0
+v    265.0 330.0 296.0
+v    314.0 330.0 456.0
+v    472.0 330.0 406.0
+f -4 -3 -2 -1
+
+v    423.0   0.0 247.0
+v    423.0 330.0 247.0
+v    472.0 330.0 406.0
+v    472.0   0.0 406.0
+f -4 -3 -2 -1
+
+v    472.0   0.0 406.0
+v    472.0 330.0 406.0
+v    314.0 330.0 456.0
+v    314.0   0.0 456.0
+f -4 -3 -2 -1
+
+v    314.0   0.0 456.0
+v    314.0 330.0 456.0
+v    265.0 330.0 296.0
+v    265.0   0.0 296.0
+f -4 -3 -2 -1
+
+v    265.0   0.0 296.0
+v    265.0 330.0 296.0
+v    423.0 330.0 247.0
+v    423.0   0.0 247.0
+f -4 -3 -2 -1
+

test-nan.obj

@@ -0,0 +1,145 @@
+# cornell_box.obj and cornell_box.mtl are grabbed from Intel's embree project.
+# original cornell box data
+  # comment
+
+# empty line including some space
+   
+
+mtllib cornell_box.mtl
+
+o floor
+usemtl white
+v nan -nan nan
+v inf -inf inf
+v 1.#IND -1.#IND 1.#IND
+v 1.#INF -1.#INF 1.#INF
+
+v 130.0 0.0  65.0
+v  82.0 0.0 225.0
+v 240.0 0.0 272.0
+v 290.0 0.0 114.0
+
+v 423.0 0.0 247.0
+v 265.0 0.0 296.0
+v 314.0 0.0 456.0
+v 472.0 0.0 406.0
+
+f 1 2 3 4 
+f 8 7 6 5
+f 12 11 10 9
+
+o light
+usemtl light
+v 343.0 548.0 227.0
+v 343.0 548.0 332.0
+v 213.0 548.0 332.0
+v 213.0 548.0 227.0
+f -4 -3 -2 -1
+
+o ceiling
+usemtl white
+v 556.0 548.8 0.0
+v 556.0 548.8 559.2
+v 0.0 548.8 559.2
+v 0.0 548.8 0.0
+f -4 -3 -2 -1
+
+o back_wall
+usemtl white
+v 549.6   0.0 559.2
+v 0.0   0.0 559.2
+v 0.0 548.8 559.2
+v 556.0 548.8 559.2
+f -4 -3 -2 -1
+
+o front_wall
+usemtl blue
+v 549.6   0.0 0
+v 0.0   0.0 0
+v 0.0 548.8 0
+v 556.0 548.8 0
+#f -1 -2 -3 -4
+
+o green_wall
+usemtl green
+v    0.0   0.0 559.2
+v    0.0   0.0   0.0
+v    0.0 548.8   0.0
+v    0.0 548.8 559.2
+f -4 -3 -2 -1
+
+o red_wall
+usemtl red
+v    552.8   0.0   0.0
+v    549.6   0.0 559.2
+v    556.0 548.8 559.2
+v    556.0 548.8   0.0
+f -4 -3 -2 -1
+
+o short_block
+usemtl white
+
+v    130.0 165.0  65.0
+v     82.0 165.0 225.0
+v    240.0 165.0 272.0
+v    290.0 165.0 114.0
+f -4 -3 -2 -1
+
+v    290.0   0.0 114.0
+v    290.0 165.0 114.0
+v    240.0 165.0 272.0
+v    240.0   0.0 272.0
+f -4 -3 -2 -1
+
+v    130.0   0.0  65.0
+v    130.0 165.0  65.0
+v    290.0 165.0 114.0
+v    290.0   0.0 114.0
+f -4 -3 -2 -1
+
+v     82.0   0.0 225.0
+v     82.0 165.0 225.0
+v    130.0 165.0  65.0
+v    130.0   0.0  65.0
+f -4 -3 -2 -1
+
+v    240.0   0.0 272.0
+v    240.0 165.0 272.0
+v     82.0 165.0 225.0
+v     82.0   0.0 225.0
+f -4 -3 -2 -1
+
+o tall_block
+usemtl white
+
+v    423.0 330.0 247.0
+v    265.0 330.0 296.0
+v    314.0 330.0 456.0
+v    472.0 330.0 406.0
+f -4 -3 -2 -1
+
+usemtl white
+v    423.0   0.0 247.0
+v    423.0 330.0 247.0
+v    472.0 330.0 406.0
+v    472.0   0.0 406.0
+f -4 -3 -2 -1
+
+v    472.0   0.0 406.0
+v    472.0 330.0 406.0
+v    314.0 330.0 456.0
+v    314.0   0.0 456.0
+f -4 -3 -2 -1
+
+v    314.0   0.0 456.0
+v    314.0 330.0 456.0
+v    265.0 330.0 296.0
+v    265.0   0.0 296.0
+f -4 -3 -2 -1
+
+v    265.0   0.0 296.0
+v    265.0 330.0 296.0
+v    423.0 330.0 247.0
+v    423.0   0.0 247.0
+f -4 -3 -2 -1
+

test.cc

@@ -67,10 +67,15 @@ TestLoadObj(
 
   std::vector<tinyobj::shape_t> shapes;
   std::vector<tinyobj::material_t> materials;
-  std::string err = tinyobj::LoadObj(shapes, materials, filename, basepath);
+
+  std::string err;
+  bool ret = tinyobj::LoadObj(shapes, materials, err, filename, basepath);
 
   if (!err.empty()) {
     std::cerr << err << std::endl;
+  }
+
+  if (!ret) {
     return false;
   }
 
@@ -152,12 +157,14 @@ std::string matStream(
         public:
             MaterialStringStreamReader(const std::string& matSStream): m_matSStream(matSStream) {}
             virtual ~MaterialStringStreamReader() {}
-            virtual std::string operator() (
+            virtual bool operator() (
               const std::string& matId,
               std::vector<material_t>& materials,
-              std::map<std::string, int>& matMap)
+              std::map<std::string, int>& matMap,
+              std::string& err)
             {
-                return LoadMtl(matMap, materials, m_matSStream);
+                LoadMtl(matMap, materials, m_matSStream);
+                return true;
             }
 
         private:
@@ -167,10 +174,14 @@ std::string matStream(
   MaterialStringStreamReader matSSReader(matStream);
   std::vector<tinyobj::shape_t> shapes;
   std::vector<tinyobj::material_t> materials;
-  std::string err = tinyobj::LoadObj(shapes, materials, objStream, matSSReader);    
+  std::string err;
+  bool ret = tinyobj::LoadObj(shapes, materials, err, objStream, matSSReader);    
   
   if (!err.empty()) {
     std::cerr << err << std::endl;
+  }
+
+  if (!ret) {
     return false;
   }
 

tiny_obj_loader.cc

@@ -5,6 +5,7 @@
 //
 
 //
+// version 0.9.15: Change API to handle no mtl file case correctly(#58)
 // version 0.9.14: Support specular highlight, bump, displacement and alpha map(#53)
 // version 0.9.13: Report "Material file not found message" in `err`(#46)
 // version 0.9.12: Fix groups being ignored if they have 'usemtl' just before 'g' (#44)
@@ -415,10 +416,9 @@ static bool exportFaceGroupToShape(
   return true;
 }
 
-std::string LoadMtl(std::map<std::string, int> &material_map,
+void LoadMtl(std::map<std::string, int> &material_map,
-                    std::vector<material_t> &materials,
+             std::vector<material_t> &materials,
-                    std::istream &inStream) {
+             std::istream &inStream) {
-  std::stringstream err;
 
   // Create a default material anyway.
   material_t material;
@@ -643,13 +643,12 @@ std::string LoadMtl(std::map<std::string, int> &material_map,
   material_map.insert(
       std::pair<std::string, int>(material.name, static_cast<int>(materials.size())));
   materials.push_back(material);
-
-  return err.str();
 }
 
-std::string MaterialFileReader::operator()(const std::string &matId,
+bool MaterialFileReader::operator()(const std::string &matId,
-                                           std::vector<material_t> &materials,
+                                    std::vector<material_t> &materials,
-                                           std::map<std::string, int> &matMap) {
+                                    std::map<std::string, int> &matMap,
+                                    std::string& err) {
   std::string filepath;
 
   if (!m_mtlBasePath.empty()) {
@@ -659,27 +658,29 @@ std::string MaterialFileReader::operator()(const std::string &matId,
   }
 
   std::ifstream matIStream(filepath.c_str());
-  std::string err = LoadMtl(matMap, materials, matIStream);
+  LoadMtl(matMap, materials, matIStream);
   if (!matIStream) {
     std::stringstream ss;
     ss << "WARN: Material file [ " << filepath << " ] not found. Created a default material.";
     err += ss.str();
   }
-  return err;
+  return true;
 }
 
-std::string LoadObj(std::vector<shape_t> &shapes,
+bool LoadObj(std::vector<shape_t> &shapes, // [output]
-                    std::vector<material_t> &materials, // [output]
+             std::vector<material_t> &materials, // [output]
-                    const char *filename, const char *mtl_basepath) {
+             std::string &err,
+             const char *filename, const char *mtl_basepath) {
 
   shapes.clear();
 
-  std::stringstream err;
+  std::stringstream errss;
 
   std::ifstream ifs(filename);
   if (!ifs) {
-    err << "Cannot open file [" << filename << "]" << std::endl;
+    errss << "Cannot open file [" << filename << "]" << std::endl;
-    return err.str();
+    err = errss.str();
+    return false;
   }
 
   std::string basePath;
@@ -688,13 +689,14 @@ std::string LoadObj(std::vector<shape_t> &shapes,
   }
   MaterialFileReader matFileReader(basePath);
 
-  return LoadObj(shapes, materials, ifs, matFileReader);
+  return LoadObj(shapes, materials, err, ifs, matFileReader);
 }
 
-std::string LoadObj(std::vector<shape_t> &shapes,
+bool LoadObj(std::vector<shape_t> &shapes, // [output]
-                    std::vector<material_t> &materials, // [output]
+             std::vector<material_t> &materials, // [output]
-                    std::istream &inStream, MaterialReader &readMatFn) {
+             std::string& err,
-  std::stringstream err;
+             std::istream &inStream, MaterialReader &readMatFn) {
+  std::stringstream errss;
 
   std::vector<float> v;
   std::vector<float> vn;
@@ -833,10 +835,13 @@ std::string LoadObj(std::vector<shape_t> &shapes,
       sscanf(token, "%s", namebuf);
 #endif
 
-      std::string err_mtl = readMatFn(namebuf, materials, material_map);
+      std::string err_mtl;
-      if (!err_mtl.empty()) {
+      bool ok = readMatFn(namebuf, materials, material_map, err_mtl);
+      err += err_mtl;
+      
+      if (!ok) {
         faceGroup.clear(); // for safety
-        return err_mtl;
+        return false;
       }
 
       continue;
@@ -913,6 +918,8 @@ std::string LoadObj(std::vector<shape_t> &shapes,
   }
   faceGroup.clear(); // for safety
 
-  return err.str();
+  err += errss.str();
-}
+  return true;
 }
+
+} // namespace

tiny_obj_loader.h

@@ -54,9 +54,10 @@ public:
   MaterialReader() {}
   virtual ~MaterialReader() {}
 
-  virtual std::string operator()(const std::string &matId,
+  virtual bool operator()(const std::string &matId,
-                                 std::vector<material_t> &materials,
+                          std::vector<material_t> &materials,
-                                 std::map<std::string, int> &matMap) = 0;
+                          std::map<std::string, int> &matMap,
+                          std::string &err) = 0;
 };
 
 class MaterialFileReader : public MaterialReader {
@@ -64,9 +65,10 @@ public:
   MaterialFileReader(const std::string &mtl_basepath)
       : m_mtlBasePath(mtl_basepath) {}
   virtual ~MaterialFileReader() {}
-  virtual std::string operator()(const std::string &matId,
+  virtual bool operator()(const std::string &matId,
-                                 std::vector<material_t> &materials,
+                                std::vector<material_t> &materials,
-                                 std::map<std::string, int> &matMap);
+                                std::map<std::string, int> &matMap,
+                                std::string &err);
 
 private:
   std::string m_mtlBasePath;
@@ -75,23 +77,27 @@ private:
 /// Loads .obj from a file.
 /// 'shapes' will be filled with parsed shape data
 /// The function returns error string.
-/// Returns empty string when loading .obj success.
+/// Returns true when loading .obj become success.
+/// Returns warning and error message into `err`
 /// 'mtl_basepath' is optional, and used for base path for .mtl file.
-std::string LoadObj(std::vector<shape_t> &shapes,       // [output]
+bool LoadObj(std::vector<shape_t> &shapes,       // [output]
-                    std::vector<material_t> &materials, // [output]
+             std::vector<material_t> &materials, // [output]
-                    const char *filename, const char *mtl_basepath = NULL);
+             std::string& err,                   // [output]
+             const char *filename, const char *mtl_basepath = NULL);
 
 /// Loads object from a std::istream, uses GetMtlIStreamFn to retrieve
 /// std::istream for materials.
-/// Returns empty string when loading .obj success.
+/// Returns true when loading .obj become success.
-std::string LoadObj(std::vector<shape_t> &shapes,       // [output]
+/// Returns warning and error message into `err`
-                    std::vector<material_t> &materials, // [output]
+bool LoadObj(std::vector<shape_t> &shapes,       // [output]
-                    std::istream &inStream, MaterialReader &readMatFn);
+             std::vector<material_t> &materials, // [output]
+             std::string& err,                   // [output]
+             std::istream &inStream, MaterialReader &readMatFn);
 
 /// Loads materials into std::map
-/// Returns an empty string if successful
+void LoadMtl(std::map<std::string, int> &material_map, // [output]
-std::string LoadMtl(std::map<std::string, int> &material_map,
+             std::vector<material_t> &materials,       // [output]
-                    std::vector<material_t> &materials, std::istream &inStream);
+             std::istream &inStream);
 }
 
 #endif // _TINY_OBJ_LOADER_H