CAEmitterCell documentation: how does color mix with asset color?

Number:rdar://31019713 Date Originated:13-Mar-2017 05:15 PM
Status:Open Resolved:
Product:Documentation Product Version:N/A
Classification:Serious Bug Reproducible:Always
Documentation at, accessed 13 March 2017, says that “the default value of this property is a color object set to opaque white.” From this, and through experimentation, I believe I have determined that the color of the emitter is the value of the `.color` property multiplied per-channel with the colors in the image that is set as the `.contents` of the emitter cell.

This is unexpected, because if I set a `.color`, I would expect it to override the color of the asset, or else the documentation should explicitly call out how the color is applied. The upshot is that, to create an asset that is tintable at run time, I had to set its contents to a pure white image with an alpha channel.

This was the result of some experimentation, and the documentation should call it out explicitly.


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