7f78237ee5
This adds a property which can be used to redirect the actor through an FBO before painting so that it becomes flattened in an image. The image can be used as a cache to avoid having to repaint the actor if something unrelated in the scene changes. It can also be used to implement correct opacity even if the actor has overlapping primitives. The property is an enum that takes three values: CLUTTER_OFFSCREEN_REDIRECT_NEVER: The default behaviour which is to never flatten the actor. CLUTTER_OFFSCREEN_REDIRECT_ALWAYS: The actor is always redirected through an FBO. CLUTTER_OFFSCREEN_REDIRECT_ONLY_FOR_OPACITY: The actor is only redirected through an FBO if the paint opacity is not 255. This value would be used if the actor wants correct opacity. It will avoid the overhead of using an FBO whenever the actor is fully opaque. The property is implemented by installing a ClutterFlattenEffect. ClutterFlattenEffect is a new internal class which subclasses ClutterOffscreen to redirect the painting to an FBO. When ClutterOffscreen paints, the effect sets an opacity override on the actor so that the image will always contain the actor at full opacity. The opacity is then applied to the resulting image before painting it to the stage. This means the actor does not need to be redrawn while the opacity is being animated. The effect has a high internal priority so that it will always occur before any other effects and it gets hidden from the application.
4.7 KiB
327x197px
4.7 KiB
327x197px
