Gdk.DrawContext¶
class — extends GObject.Object
Base class for objects implementing different rendering methods.
GdkDrawContext is the base object used by contexts implementing different
rendering methods, such as CairoContext or GLContext.
It provides shared functionality between those contexts.
You will always interact with one of those subclasses.
A GdkDrawContext is always associated with a single toplevel surface.
Methods¶
begin_frame¶
:::warning Deprecated since 4.16 This API is deprecated. :::
Indicates that you are beginning the process of redrawing region
on the context's surface.
Calling this function begins a drawing operation using context on the
surface that context was created from. The actual requirements and
guarantees for the drawing operation vary for different implementations
of drawing, so a CairoContext and a GLContext
need to be treated differently.
A call to this function is a requirement for drawing and must be
followed by a call to DrawContext.end_frame, 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 DrawContext.get_frame_region to
query the region that must be drawn.
When using GTK, the widget system automatically places calls to
DrawContext.begin_frame and DrawContext.end_frame via the
use of GskRenderers, so application code
does not need to call these functions explicitly.
Parameters:
region— minimum region that should be drawn
end_frame¶
:::warning Deprecated since 4.16 This API is deprecated. :::
Ends a drawing operation started with DrawContext.begin_frame.
This makes the drawing available on screen.
See DrawContext.begin_frame for more details about drawing.
When using a GLContext, this function may call glFlush()
implicitly before returning; it is not recommended to call glFlush()
explicitly before calling this function.
get_display¶
Retrieves the GdkDisplay the context is created for
get_frame_region¶
:::warning Deprecated since 4.16 This API is deprecated. :::
Retrieves the region that is currently being repainted.
After a call to DrawContext.begin_frame this function will
return a union of the region passed to that function and the area of the
surface that the context determined needs to be repainted.
If context is not in between calls to DrawContext.begin_frame
and DrawContext.end_frame, None will be returned.
get_surface¶
Retrieves the surface that context is bound to.
is_in_frame¶
:::warning Deprecated since 4.16 This API is deprecated. :::
Returns True if context is in the process of drawing to its surface.
This is the case between calls to DrawContext.begin_frame
and DrawContext.end_frame. In this situation, drawing commands
may be effecting the contents of the context's surface.
Properties¶
display¶
The GdkDisplay used to create the GdkDrawContext.
surface¶
The GdkSurface the context is bound to.