After we have analyzed the default Gralloc module implementation, we want to briefly look at another Gralloc module implementation so that we can compare how a Gralloc module should be implemented on varying Graphic hardware.
The Gralloc module we will analyze in this section is the Gralloc module used by the Android emulator. The default Gralloc module gralloc.default.so only uses framebuffer devices and it doesn't use GPU. If the default Gralloc module is used, OpenGL support has to be implemented in the software layer. This is the case with VirtualBox for the time being, since there is no Mesa/DRM-compliant implementation in the VirtualBox host side for OpenGL. This doesn't mean VirtualBox doesn't support OpenGL. It does support OpenGL and 3D hardware acceleration, but the implementation is not compliant with the open source Mesa/DRM architecture.