[vbox-dev] [PATCH] Fix for 3D acceleration for NVIDIA / Linux hosts; Closes Bug #13653

[Alexey Eromenko]

After 3 days of almost sleepless nights, I was able to find the bug !

Fix is related to multi-threading, and I don't understand it's
implications fully. And my fix could kill 3D acceleration on any other
hosts, so proceed with caution !

I call Oracle to review this patch, release v5.0.0-BETA5 early with a
fix, so we could test 3D acceleration on all hosts. (Windows/Mac OS
X/Linux) and all GPU vendors (IntelAMD/NVIDIA).

But this bug is worth it !

22.May.2015.
-- 
-Alexey Eromenko "Technologov"
-------------- next part --------------
--- /home/alexey/vbox-orig/VirtualBox-5.0.0_BETA4/./src/VBox/HostServices/SharedOpenGL/render/renderspu_glx.c	2015-05-18 18:02:05.000000000 +0300
+++ ./src/VBox/HostServices/SharedOpenGL/render/renderspu_glx.c	2015-05-22 23:33:33.000000000 +0300
@@ -1922,11 +1922,10 @@
             XSync(window->visual->dpy, 0);
         }
     }
 }
 
-#define CR_RENDER_FORCE_PRESENT_MAIN_THREAD
 
 void renderspu_SystemVBoxPresentComposition( WindowInfo *window, const struct VBOXVR_SCR_COMPOSITOR_ENTRY *pChangedEntry )
 {
     /* the CR_RENDER_FORCE_PRESENT_MAIN_THREAD is actually inherited from cocoa backend impl,
      * here it forces rendering in WinCmd thread rather than a Main thread.