Removing Blender Game Engine from Blender 2.8
Folders removed entirely:
* //extern/recastnavigation
* //intern/decklink
* //intern/moto
* //source/blender/editors/space_logic
* //source/blenderplayer
* //source/gameengine
This includes DNA data and any reference to the BGE code in Blender itself. 
We are bumping the subversion. 
Pending tasks:
* Tile/clamp code in image editor draw code. 
* Viewport drawing code (so much of this will go away because of BI removal
that we can wait until then to remove this. 

OpenGL/BGE: Remove RAS_StorageIM (glBegin/glEnd rendering of mesh data)
The only use we had for RAS_StorageIM was to render derived meshes using
Blender's mesh drawing.  This is now handled as a special case in
RAS_OpenGLRasterizer instead of in RAS_StorageIM. 
We are now left with RAS_StorageVA and RAS_StorageVBO.  At the moment
vertex arrays are still the default since our vertex array with display
lists implementation is still much faster than our VBO code in a lot of
cases.  As we improve our VBO code, we can drop vertex arrays since
Blender's minimum OpenGL version is being bumped up to 2.1, which
supports VBOs. 

BGE: Potential fix for [#35522] Broken game engine compatibility since 2.66a on some ATI cards? 
Disabling display lists for legacy ATI cards since they don't support display lists well. 
Also removing an unused variable from the display list rasterizer. 

BGE: Some as of yet unmerged work I did in the Swiss branch.  These changes include:2012-12-18T20:56:25ZMitchell Stokesmogurijin@gmail.comMitchell Stokesmogurijin@gmail.com2012-12-18T20:56:25Zhttps://git.blender.org/gitweb/gitweb.cgi/blender.git/commitdiff/ef0473994b6b21aa49bbfab26a483d90d0fef004

BGE: Some as of yet unmerged work I did in the Swiss branch.  These changes include:
* Cleaning up the conversion code to avoid a per-face material conversion.  Materials are now stored in buckets and only converted if a new material is found.  This replaces some of Campbell's earlier work on the subject.  His work wasn't as thorough, but it was much safer for a release. 
* Shaders are only compiled for LibLoaded materials once.  Before they could be compiled twice, which could really slow things down. 
* Refactoring the rasterizer code to use a strategy design pattern to handle different geometry rendering methods such as immediate mode, vertex arrays and vertex buffer objects.  VBOs are added, but they will be disabled in a following commit since they are still slower than vertex arrays with display lists.  However, VBOs are still useful for mobile, so it's good to keep them around. 
* Better multi-uv support.  The BGE should now be able to handle more than two UV layers, which should help it better match the viewport. 

BGE guardedalloc, Uses WITH_CXX_GUARDEDALLOC but gives a string to MEM_mallocN for better tracking memory usage. 
* off by default. 
* new/delete are at the bottom of each class
* python BGE objects have the new/delete in the Py_Header macro. 

2.50:
svn merge https://svn.blender.org/svnroot/bf-blender/trunk/blender -r19820:HEAD
Notes:
* Game and sequencer RNA, and sequencer header are now out of date
a bit after changes in trunk. 
* I didn't know how to port these bugfixes, most likely they are
not needed anymore. 
* Fix "duplicate strip" always increase the user count for ipo. 
* IPO pinning on sequencer strips was lost during Undo. 

BGE: restore a feature that was lost in 2.48: sharing of display lists between duplic... 2009-04-18T09:14:51ZBenoit Bolseebenoit.bolsee@online.beBenoit Bolseebenoit.bolsee@online.be2009-04-18T09:14:51Zhttps://git.blender.org/gitweb/gitweb.cgi/blender.git/commitdiff/53fd3847bcb577d580a16217a27b67fd3f679969

BGE: restore a feature that was lost in 2.48: sharing of display lists between duplicated objects. 

Merge of first part of changes from the apricot branch, especially2008-09-04T20:51:28ZBrecht Van Lommelbrechtvanlommel@pandora.beBrecht Van Lommelbrechtvanlommel@pandora.be2008-09-04T20:51:28Zhttps://git.blender.org/gitweb/gitweb.cgi/blender.git/commitdiff/cb89decfdcf5e6b2f26376d416633f4ccf0c532d

Merge ... first part of changes from the apricot branch, especially
the features that are needed to run the game.  Compile tested with
scons, make, but not cmake, that seems to have an issue not related
to these changes.  The changes include:
* GLSL support in the viewport and game engine, enable in the game
menu in textured draw mode. 
* Synced and merged part of the duplicated blender and gameengine/
gameplayer drawing code. 
* Further refactoring of game engine drawing code, especially mesh
storage changed a lot. 
* Optimizations in game engine armatures to avoid recomputations. 
* A python function to get the framerate estimate in game. 
* An option take object color into account in materials. 
* An option to restrict shadow casters to a lamp's layers. 
* Increase from 10 to 18 texture slots for materials, lamps, word. 
An extra texture slot shows up once the last slot is used. 
* Memory limit for undo, not enabled by default yet because it
needs the .B.blend to be changed. 
* Multiple undo for image painting. 
* An offset for dupligroups, so not all objects in a group have to
be at the origin. 

Sync with Apricot Game Engine
=============================
* Clean up and optimizations in skinned/deformed mesh code. 
* Compatibility fixes and clean up in the rasterizer. 
* Changes related to GLSL shadow buffers which should have no
effect, to keep the code in sync with apricot. 

BGE memleak fix: OpenGL Display Lists not deleted when switching scene
This fix also improves performance of Display List for replica objects: Display List ID caching is now enabled for replica objects which avoids a tree search on each frame and for each replica. 

Patch [#7743] Enable display lists when vertex arrays are enabled, by Ovidiu Sabou. 
this patch enable GE two use both vertex array and display lists.  and speed up the engine a little, by the way thanks ovidiu.