Sprite

A sprite is a is a top-level rendering element similar to a canvas that paints onto a transparent layer over the entire window that is cleared every render pass. Sprites are used for text cursors in text field and text editor, and for drag and drop. To support cursor sprites and other animations, the sprites are redrawn at a minimum update rate that is at least as fast as core.SystemSettingsData.CursorBlinkTime.

Sprites can also receive mouse events, within their event bounding box, so they can be used for dynamic control functions, like the “handles” in a drawing program, as in the Cogent Canvas app.

The primary features of sprites are:

• They are not under control of the layout system, and can be placed anywhere. That is because they are not widgets, they are simpler rendering elements. See core.Sprite.

• The sprite layer is cleared every time and overlaid on top of any other content, whereas the scene normally accumulates drawing over time so that different widget-regions can be focally updated without having to redraw the entire scene every time.