Used to manage synchronisation between tasks on async compute queues and the graphics queue.
Not all platforms support Graphics fences. See SystemInfo.supportsGraphicsFence.
A GraphicsFence represents a point during GPU processing after a specific compute shader dispatch or draw call has completed. It can be used to achieve synchronisation between tasks running on the async compute queues or the graphics queue by having one or more queues wait until a given fence has passed. This is an important consideration when working with async compute because the various tasks running at the same time on the graphics queue and the async compute queues are key to improving GPU performance.
GPUFences do not need to be used to synchronise a GPU task writing to a resource that will be read as an input by another. These resource dependencies are automatically handled by Unity.
GPUFences should be created via Graphics.CreateGraphicsFence or CommandBuffer.CreateGraphicsFence. Attempting to use a GraphicsFence that has not been created via one of these functions will result in an exception.
It is possible to create circular dependencies using GraphicsFences that, if executed, would deadlock the GPU. Unity will detect such circular dependencies in the Editor and raise exceptions if any exist after calls to Graphics.CreateGraphicsFence, Graphics.WaitOnGraphicsFence, Graphics.ExecuteCommandBuffer, Graphics.ExecuteCommandBufferAsync, ScriptableRenderContext.ExecuteCommandBuffer, ScriptableRenderContext.ExecuteCommandBufferAsync.
See Also: SystemInfo.supportsGraphicsFence, Graphics.CreateGraphicsFence, Graphics.WaitOnGraphicsFence, CommandBuffer.CreateGraphicsFence, CommandBuffer.WaitOnAsyncGraphicsFence, Graphics.ExecuteCommandBuffer, Graphics.ExecuteCommandBufferAsync, ScriptableRenderContext.ExecuteCommandBuffer, ScriptableRenderContext.ExecuteCommandBufferAsync.
| passed | Determines whether the GraphicsFence has passed.Allows the CPU to determine whether the GPU has passed the point in its processing represented by the GraphicsFence. |