Merge branch 'develop' of github.com:syoyo/tinyobjloader into develop

appveyor.yml

@@ -7,7 +7,6 @@ install:
   # All external dependencies are installed in C:\projects\deps
   #######################################################################################
   - mkdir C:\projects\deps
-  - pushd C:\projects\deps
 
   #######################################################################################
   # Install Ninja
@@ -17,7 +16,6 @@ install:
   - 7z x ninja.zip -oC:\projects\deps\ninja > nul
   - set PATH=C:\projects\deps\ninja;%PATH%
   - ninja --version
-  - popd
 
 build_script:
   - cd tests

experimental/viewer.cc

@@ -271,9 +271,8 @@ bool LoadObjAndConvert(float bmin[3], float bmax[3], const char* filename, int n
               int f0 = idx0.vn_idx;
               int f1 = idx1.vn_idx;
               int f2 = idx2.vn_idx;
-              assert(f0 >= 0);
-              assert(f1 >= 0);
-              assert(f2 >= 0);
+
+              if (f0 >= 0 && f1 >= 0 && f2 >= 0) {
                 assert(3*f0+2 < attrib.normals.size());
                 assert(3*f1+2 < attrib.normals.size());
                 assert(3*f2+2 < attrib.normals.size());
@@ -288,6 +287,12 @@ bool LoadObjAndConvert(float bmin[3], float bmax[3], const char* filename, int n
                 n[1][0] = n[0][0]; n[1][1] = n[0][1]; n[1][2] = n[0][2];
                 n[2][0] = n[0][0]; n[2][1] = n[0][1]; n[2][2] = n[0][2];
               }
+            } else {
+              // compute geometric normal
+              CalcNormal(n[0], v[0], v[1], v[2]);
+              n[1][0] = n[0][0]; n[1][1] = n[0][1]; n[1][2] = n[0][2];
+              n[2][0] = n[0][0]; n[2][1] = n[0][1]; n[2][2] = n[0][2];
+            }
 
             for (int k = 0; k < 3; k++) {
               vb.push_back(v[k][0]);