Main news from version 14 to version 15. (See 'Detailed changes' for the full list of news).
General:

GiD named user licence (login):

Node limit increased to 10,000 nodes for free version.
Graphical fonts can be drawn with even smoother edges using lcd subpixel rendering on preferences --> fonts panel.
Each GiD version stores its own copy of user preferences, instead of being shared by all versions.
Problemtypes allow extra folder inside user preferences folder.
Register GiD menus separated by type of licence:

New GiD variable WarnLineHeight also in preferences window (General->Interface->Number of message lines).
GiD inner code preferences and variables re-structured, and only saved the non-default ones.
Video: added new mp4 format (and others avi, webm, transparency), added quality (bitrate) control and up to 200 fps.
macOS : gid projects (folders with extension .gid) display GiD project icon and can be double-clicked to be opened with GiD.
Internet retrieve : Fonts and message catalogs for other languages can be downloaded from internet retrieve:

Pre-process

New import option, to import gidml mesh format (input/output format for GiD Mesh Library).
Collada format import. Import as mesh or as OpenGL list with textures.

Abaqus mesh .inp import plugin.

Ply import allow line elements
Exodus II (HDF5) format import and export of preprocess mesh
G-code (control machine path)s import e.g. 3D printers

Raster GDAL import, option to smooth values to nodes or not
Create one geometric line by line element
Force points to volume mesh available also for structured and semi-structured volumes.
Contact volume visualization enhancement: draw lines joining master-slave surface points (as a way to represent the transform matrix)

Contact volume implemented also for different shaped surfaces with holes.
Skip Entities option can now be used also for non-NURBS surfaces.
Create objects, allow pick existing points to define radius, height,...
Create dimension, radius by 3 nodes in mesh view.
New 'Also higher entities' option to send entities to layer or send to back.
DeleteAlsoLower GiD variable and in menus and toolbar to delete also lower entities in geometry or mesh
Group assign/unassign entities show menu only with allowed types
Contextual menu of groups new 'Allowed' menu to set the type of entities and element types allowed to belong to a group
The whole meshing process enhanced improving performance and parallelization when meshing.
Spatial overlapped labels can be drawn in red:

Post-process:

Graphs window: new clipboard copy option in contextual menu (e.g. to allow to paste graph values in MS Excel).
Graphs labels as in postprocess view.
Line graphs: added 'Line projection' and '2d constraint' options.
Animation of complex vectors: harmonic animation.
Create results window: allow results 'on gauss points' with more than 1 gauss point.
Create statistical results window: root mean square.
Selection allow be inverted.
Show Min Max: Now the values are drawn with a legend, instead of using labels, if lots of nodes have minimum or maximum values.
Add to default macros toolbar the GraphGaussResult to create graph of gauss point results.
Label Gauss Points: new option to display gauss point id and result on gauss points.
Added three simple model animations in the results animation window:

Customization:

Drag and drop a .tcl file over GiD will load (source) it.
New package gid_graph to easily show a window graph.

MessageBoxGetFilename directory, new option to allow select a folder.
GiD_Geometry get line|surface <id> ?-force? render_mesh, to obtain the information of the render mesh of the line or surface.
GiD_Geometry get point|line|surface|volume <id> new sub-option mesh to get the simulation mesh.
GiD_Geometry get volume new options has_holes|index_boundaries.
GiD_Geometry list Tcl command new filter -allowed_types.
GiD_EntitiesLayers assign_front_layer ?-also_lower_entities? geometry|mesh points|lines|surfaces|volumes|nodes|elements <selection> .
Groups edit|get allowed_element_types to restrict types of elements.
GiD_EntitiesGroups get, new -visible flag to get only visible entities.
GiD_EntitiesGroups unassign, new -element_type <types_allowed> option to unassign only some element types.
GiD_MeshData size | size_by_cordal_error | size_background_mesh | size_correct | unstructured | mesher | num_divisions | element_type | mesh_criteria | reset .
GiD_Mesh list new filter -element_type <list_of_types> .
GiD_Mesh getelement, more sub-options: from_edge, num_faces, edge_linear, num_edges .
GiD_Mesh get element <num> normal|tangent|center|connectivities .
GiD_Info mesh nodes|elements new options -layer <layer_name> -group <goup_name> .
New subcommand to calculate inertia tensor: GiD_Tools mesh mass_properties $tetrahedra_ids | -boundary_elements $triangle_ids .
GiD events, updated nomenclature, and now can register multiple procs to be called .
GiD_Info events -args <event_name> .
New events: GiD_Event_AfterInsertGIDProject, GiD_Event_AfterRepair, etc.
GidUtils::PickEntities allow filter selection by element type, curve type, etc.
GidUtils::PickEntities "faces ?FaceParentType Triangle Quadrilateral...?" .
GiD_Raster interpolate ?-closest? , new option to map discrete integer-coded values, returning the value of the closest grid node.

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