gdk:draw-context-begin-frame (context region)

context -- a gdk:draw-context object used to draw the frame
region -- a cairo:region-t instance with the minimum region that should be drawn

Indicates that you are beginning the process of redrawing region on the surface of context. Calling this function begins a drawing operation using the context on the surface that the context was created from. The actual requirements and guarantees for the drawing operation vary for different implementations of drawing, so a gdk:cairo-context and a gdk:gl-context object need to be treated differently.

A call to this function is a requirement for drawing and must be followed by a call to the gdk:draw-context-end-frame function, which will complete the drawing operation and ensure the contents become visible on screen.

Note that the region passed to this function is the minimum region that needs to be drawn and depending on implementation, windowing system and hardware in use, it might be necessary to draw a larger region. Drawing implementation must use the gdk:draw-context-frame-region function to query the region that must be drawn.

When using GTK, the widget system automatically places calls to the gdk:draw-context-begin-frame and gdk:draw-context-end-frame functions via the use of gsk:renderer objects, so application code does not need to call these functions explicitly. This function is deprecated since 4.16. Drawing directly to the surface is no longer recommended. Use the gsk:render-node and gsk:renderer API.