In this chapter, we explored and reviewed two Gralloc HAL module implementations, the default Gralloc module and the one used by Android emulator. The default Gralloc HAL uses framebuffer devices only and the OpenGLES support uses a software implementation. The one used by Android emulator is a hardware emulation on the host side. The implementation is similar to the GPU-based Gralloc module.
Since graphics systems are so complex, we will continue exploring this topic a little more when looking at VirtualBox-specific implementation in the next chapter. We will explain the loading process of Gralloc HAL and OpenGL ES libraries. We will build a VirtualBox extension pack for Android so that we can utilize the capability provided by VirtualBox.
