1. A method comprising: combining intercepted buffer-based architecture three-dimensional (3D) graphics commands produced by an application program with a 3D graphics command stream of a fusion program in order to integrate a 3D object based on the intercepted 3D graphics commands into a 3D scene; and providing an input received at the fusion program to the application program, comprising mapping an input event at the fusion program into an input event of the application program, where the 3D object is a target of the input event, based on a contextual difference of the 3D object between the fusion program and the application program by reverse-mapping the input from a context of the 3D object of the fusion program buck to the context of the application program.