Patent ID: 8984509
Filing Date: 2015-03-17
Classification: G06F,G09G

Abstract:
1. A virtual machine display device, comprising: a first virtual machine, a second virtual machine, a virtual machine controller which controls the first and second virtual machines, a first memory which holds screen data representing a screen layer of the first virtual machine, and a second memory which holds screen data representing a screen layer of the second virtual machine, the virtual machine display device adapted to combine screen layers of the first and second virtual machines for displaying a combined screen on a display device, the first virtual machine including: a dummy layer generating section which, in the case where a screen layer of the second virtual machine is generated, generates a dummy layer for managing the generated screen layer by the first virtual machine; a display layer management section which manages screen layer management information including at least a display order of screen layers of the first virtual machine and the dummy layer; a display driver switching section which switches display control to the first virtual machine in the case where the dummy layer is not generated, and switches the display control to the second virtual machine in the case where at least the one dummy layer is generated; and a first screen data combining section which combines screen layers of the first virtual machine, using the screen data held in the first memory, based on the screen layer management information in the case where the display driver switching section switches the display control to the first virtual machine, wherein the virtual machine controller includes a driver switching notification section which designates the second virtual machine to combine screen layers in the case where the display driver switching section switches the display control to the second virtual machine, and the second virtual machine includes a second screen data combining section which combines the screen layers of the first and second virtual machines, using the screen data held in the first and second memories, based on the screen layer management information, in the case where the driver switching notification section designates the second virtual machine to combine the screen layers.