ShadowDrawable

This class is a thin wrapper around the library's core draw functionalities, allowing its shadows to be drawn manually.

The user is responsible for invalidating the current draw whenever a property's value is changed. Failure to do so can result in a few different possible defects, depending on the specific setup, including misaligned clip regions, stale draws, etc.

Clipped instances with irregular shapes on API levels 30+ must have the outline Path set manually using the setClipPathProvider function. This is analogous to setting a ViewPathProvider on a target View.

All ShadowDrawable instances created with an owner should call dispose. This is technically not necessary for the those created with the @RequiresApi(29) constructor, but it is still safe to call dispose on such instances. Use after disposal is not an automatic Exception, but it is not advised, and there is no guaranteed behavior.

The Drawable class's required setColorFilter override is a no-op here.

The color compat functionality is exposed here through the colorCompat property, which is set to black by default, disabling the tinting. Setting any non-black color enables color compat, and the ambientColor and spotColor values are then ignored.

Color compat requires an owner View that must be attached to the onscreen hierarchy. Instances created with the @RequiresApi(29) constructor will throw an IllegalStateException upon any attempt to set colorCompat.

Normally the owner is just the View in which the draw happens, though that's not strictly necessary. However, due to a limitation in the core graphics framework, the color compat mechanism needs to track its onscreen location, and the lighting effects may go out of sync with the expected appearance if the drawing View moves differently than the owner.

Color compat shadows are always clipped to the drawable's bounds.