Followup to PR #962:
- the display of spheres was no longer correct,
- allow loading of c3t3 without any facets and cells (only vertices
with weights),
- fix the display of spheres, with better shaders,
- `Scene_c3t3_item`: do not draw edges, in FlatPlusEdges, during a
`drawWithNames()`, to optimize speed,
- `Viewer`: do not use anti-aliasing during `drawWithNames()`
That assertion verifies that the value `value_outside` is considered at
a value *outside* of the domain. Otherwise Mesh_3 will crash with an
assertion saying that "infinite cells should not be in the C3t3".
That is an attempt to fix a warning:
```
../include/CGAL/utility.h:101:33: warning: 'index2' may be used uninitialized in this function [-Wmaybe-uninitialized]
: first(a), second(b), third(c)
^
In file included from ../include/CGAL/Mesh_3/Mesher_3.h:35:0,
from ../include/CGAL/refine_mesh_3.h:32,
from ../include/CGAL/make_mesh_3.h:30,
from ../test/Mesh_3/test_c3t3_extract_subdomains_boundaries.cpp:9:
../include/CGAL/Mesh_3/Refine_facets_manifold_base.h:162:17: note: 'index2' was declared here
int index1, index2;
^
```
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(227): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(227): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(503): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(503): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(517): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(517): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(518): warning C4267: 'return': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(561): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(561): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(814): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(814): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(815): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(815): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(855): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(855): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(857): warning C4267: 'initializing': conversion from 'size_t' to 'const int', possible loss of data
> CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h(857): warning C4267: 'initializing': conversion from 'size_t' to 'int', possible loss of data
> /Mesh_3/include/CGAL/Mesh_3/Refine_facets_3.h:632:25: error: declaration of 'Tr' shadows template parameter
> template<class Tr, class Cr, class MD, class C3T3_, class Ct, class C_>
Laurent Rineau
Andreas Fabri
Sebastien Loriot
Jane Tournois
Philipp Möller
Sébastien Loriot