0032422: Mesh - Weird rendering
0029641: Mesher produce 'bad' result for extruded spline with given deviation coefficient
Added method BRepMesh_NURBSRangeSplitter::getUndefinedInterval() intended to compute checkpoint parameters for those NURBS surfaces which have no intervals at all. In this case number of poles is used to produce artificial regular grid which can be refined further. Add at least one midpoint for surfaces with one interval and only two poles.
Added BRepMesh_ExtrusionRangeSplitter and BRepMesh_UndefinedRangeSplitter derivatives from BRepMesh_NURBSRangeSplitter intended to handle special cases of extrusion surfaces and general surfaces with undefined parameters.
Removed testgrids 'bugs/vis' and '3rdparty'; tests have been redistributed across other grids.
Moved testgrid 'v3d/ivtk' into dedicated 'vtk/ivtk'.
Added testgrid 'vselect' dedicated to 3D viewer picking/selection functionality
and filled with tests from 'v3d/vertex', 'v3d/face' and similar groups.
Added testgrid 'opengl' dedicated to OpenGL driver low-level functionality (GLSL programs and similar)
and filled with tests from 'v3d/glsl', 'v3d/raytrace', '3rdparty/fonts', 'bugs/vis' (portion) and similar.
Added testgrid 'opengles3' dedicated to OpenGL ES 3.0 driver low-level functionality
and reusing tests from 'opengl' testgrid.
Subgroup 'opengles3/raytrace' is disabled on Windows, as Ray-Tracing currently requires OpenGL ES 3.2.
while ANGLE library implements only OpenGL ES 3.0.
Added testgrid 'opengles2' dedicated to OpenGL ES 2.0 driver low-level functionality
and reusing a limited subset of passing tests from 'opengl' testgrid.
Currently testgrid is activated only on Windows platform when using ANGLE library
(properietary OpenGL ES drivers do not allow creation of restricted 2.0 context).
Test cases have been cleaned out to put bug description into log,
to properly load necessary plugins and to explicitly dump viewer.
