An efficient, low-level, bindless graphics API for Rust.
Command buffers and encoders
A command buffer is a serialized list of drawing and compute commands. Unlike with vulkan, command buffers are not what you use to create commands, but only the result of creating these commands. Gfx, borrowing metal's terminology, uses encoders to build command buffers. This means that, in general, users of the gfx crate don't manipulate command buffers directly much and interact mostly with encoders.
Encoder in gfx corresponds to interacting with:
OpenGL and earlier versions of D3D don't have an explicit notion of command buffers or encoders (with the exception of draw indirect commands in late versions of OpenGL, which can be seen as a GPU-side command buffer). They are managed implicitly by the driver.
The factory is what lets you allocate GPU resources such as buffers and textures.
Each gfx backend provides its own factory type which implements both:
gfx::Factory is roughly equivalent to:
OpenGL does not have a notion of factory (resources are created directly off of the global context). D3D11 has a DXGI factory but it is only used to interface with other processes and the window manager, resources like textures are usually created using the device.
Pipeline state (PSO)
Handles internally use atomically reference counted pointers to deal with memory management. GPU resources are not destroyed right away when all references to them are gone. Instead they are destroyed the next time Device::cleanup is called.