support alpha keyword arg

[ssfrr]

sometimes I find myself wanting to use the alpha channel to visualize some parameter, or just quickly tweak the transparency to improve aesthetics for a dense plot.

The first thing I tried was just adding an alpha=0.5 keyword arg to my scatter call, just to see if it would work. It didn't. :)

I'm guessing that there's some way to specify the color from scratch and include the alpha channel, but the default colors are pretty good and I just want to tweak the transparency without needing to override the default colors otherwise.

[SimonDanisch]

I didn't really like the alpha keyword, but I think it does make sense how you put it!
It should also be reasonably easy to implement! I'll try to include it soon :)

[asinghvi17]

alpha is implemented now IIRC.

[SimonDanisch]

It's just included, but not implemented yet :(

[jtrakk]

transparency and alpha both appear in the docs. What is the difference?

[cossio]

Bump. Particularly @jtrakk question?

[SimonDanisch]

uhm, alpha should be removed from the docs, since isn't implemented yet :(
transparency accepts a bool, to indicate if something should be rendered transparent or not (regardless of the alpha)...The effect is, that it renders without writing to the depth buffer, which results in objects behind it being rendered.

[jkrumbiegel]

I feel like this should be renamed to write_depth_buffer because transparency promises more than it can hold.

[czimm79]

This feature has been missing for awhile, and I'd like to help. I'm pretty inexperienced with contributing but I'd like to learn.

Is there a way to get the current color or colormap, then simply rewrite alpha=0.5 as color=(getcurrentcolor(), 0.5)?

[SimonDanisch]

implemented in #2900