When using premultiplied alpha in the Spine Web Player, if you encounter parts of your Spine animation turning black, it could be due to several reasons. One common cause is a mismatch between the export settings in the Spine Editor and the runtime settings in the Spine Web Player. If premultiplied alpha is enabled during export but not correctly handled in the web player, or vice versa, it can lead to visual artifacts such as black areas in your animation.
Another potential issue could be related to the blending modes used in your Spine project. For example, if a slot uses additive blending and is displayed against a transparent background, it might not render as expected, leading to unexpected black backgrounds or artifacts. This is because additive blending relies on the underlying color to calculate the final color, and with a transparent background, there's nothing to blend with, which can result in black areas if the original images contain black.
To resolve these issues, ensure that your export settings from the Spine Editor match the runtime configuration in the Spine Web Player. Specifically, if you're using premultiplied alpha, make sure to enable it in the Spine Web Player's configuration. Additionally, review the blending modes used in your Spine project and adjust them as necessary, especially if you're working with transparent backgrounds or layers.
