This text explains the promise texture system within Chromium’s Viz compositor, an architectural framework that allows the browser to handle complex GPU drawing operations across different threads. By using placeholder images during the initial recording phase, the system enables the compositor thread to operate independently of the GPU main thread, preventing driver-related delays. These "promises" are later fulfilled on the GPU thread, where actual texture handles are resolved and synchronized through the SharedImage system. The documentation details the specific class hierarchies and lifecycle stages required to move a frame from initial rasterization to final display. Finally, it highlights the ongoing transition from the Ganesh rendering engine to the newer Graphite framework, which modernization efforts are currently reshaping how these asynchronous GPU tasks are managed.