…igl/libigl into dev-intrinsic-delaunay

…igl/libigl into dev-intrinsic-delaunay

delaunay unit tests, expose is_delaunay, templates, PlainObject -> Matrix

* fix typo

* fix typo for solving compile error

exposed heat_geodesics in python binding

* Fixed two memory leaks

One pointer to allocated memory wasn't freed and realloc didn't have proper error handling. Additionally UB has been identified, because a pointer to a local variable is returned.

* Memory leak removed, cause be setting reference to NULL instead of deleting the object

Shewchuk's predicates support

* Replicate linking error described in #1168

* Fix #1168.

* Ensure header-only mode works.

* Disambiguate exactinit call in unit test.

For translating centre, the distance should be the half of width of the sub cell instead of the width h.

…riteOBJ (#1108)

* templates

* Extending igl::cat to work with a std::vector of matrices

* Small fix

* Fixing std::vector version of adjacency_list

* Change MatrixBase -> PlainObjectBase to fix compile error in boundary_loop

* Fixing function definition for adjacency_list

* Added test for cat

* Extending writeOBJ to work with mixed tri/quad meshes

* Code review feedback

* Writing lines instead of faces

* Adding template for test compile

* Fixing brace style and switching to trigraph

* Fixing braces

* another brace

* PlainObjectBase -> MatrixBase

* Sneaking in a few more template instantiations

* PlainObjectBase for outputs

* adding template to fix appveyor windows link error

Viewer const accessors + use viewport size (fixes #1166, fixes #1167).

* Update GLFW and Embree + use git urls (fixes #1019).

* Simplify Embree build.

* More robust top-level project detection.

fix matlab options

Fixing missing symbol error for python

Bug fix and feature improvement for marching cubes

Fix templating in sort_triangles

✨ Enable OpenMP for MSVC users (#1147)