Retained Mode vs. Immediate Mode
In retained mode, the graphics library exposes an API to the application for building/updating a scene. However, the graphics library is in charge of issuing drawing commands. In contrast, an immediate-mode API allows the application to issue the drawing commands. Retained-mode APIs abstract away initialization, state maintenance and cleanup, but uses more memory. Immediate-mode APIs allow for more targeted optimizations.
Retained Mode Versus Immediate Mode - Win32 apps | Microsoft Docs. Microsoft. docs.microsoft.com .