@Anonymous
Adding to @blair reply..
That option Transparent slider is based on how the appearance was actually created or from what template it was started from.. Meaning that entire section is not always the same or not every appearance would have that option.
For example if an appearance was based on the metal appearance template, that option transparent would not be there while another one would have it. This is what i called a half baked appearance.. You are starting with something and defining its standard options.
If an appearance is started based on the "generic appearance", then all of those appearances would have the same options, settings and the transparent slider or that option would be there.. This is my scratch baked appearance.. Basically I'm starting with a clean slate.
As @blair indicate you would need to create a new generic appearance in order to have the option or pick one of the per-defined appearances with that option.
Update: Attaching a computer presentation (powerpoint) that I did in May about appearances. Hopefully some of the info is useful to you..
Mark Lancaster
& Autodesk Services MarketPlace Provider
Autodesk Inventor Certified Professional & not an Autodesk Employee
Likes is much appreciated if the information I have shared is helpful to you and/or others
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