Add framework for animation options (fixed)

[gadenbuie]

Fixed version of #18

This is an extension of #16 and that will help us move towards resolving #17.

It sets up a framework for creating, setting and transporting the animation options that may need to be passed through several helper functions to get to the final animate_plot() or static_plot() call.

It also lets

1. The user set animation options for the current session, much like theme_set() in ggplot2
2. Us create "default" animation options by verb family
3. Us define or change the global defaults easily from one place.

I've created a more detailed explanation in this gist that also demonstrates some of the work from #16.

I'm bundling this as a PR to a PR #16 in hopes that it's a little easier to review 😄

[DavZim]

Loving the idea with the animation options and all the other work you have put into this.

Some thoughts that I had while reading through the code:

• currently we use our default values as defined in zzz-package.R only if ggplot has not set another value (getFromNamespace("theme_env", "ggplot2")$current$text$size) see https://github.com/gadenbuie/tidy-animated-verbs/blob/bbb8410c787fdbdf1231c12aafde295665072d71/R/animate_options.R#L203-L205 etc. Should we maybe revers the order, that the ggplot theme is only used if somehow our default value is not set? Currently on my (high-DPI) display, the font-text is way too large at its default (when using ggplots-values). For me around 5 works for the text-size.
• I don't quite understand the advantages of get_input_text(), what is the advantage of creating a list first and then pasting its x and y argument again? 5dcdf5f and following. Or is it just necessary for the quosures?
• Currently we pass the dots to the animation-function in the join and set functions, but not to the tidyr animation functions. Are they still in use? If so, should we maybe standardise its usage?

Otherwise I didn't find anything that needed changing.

[gadenbuie]

getFromNamespace("theme_env", "ggplot2")$current$text$size: Should we maybe reverse the order, that the ggplot theme is only used if somehow our default value is not set? Currently on my (high-DPI) display, the font-text is way too large at its default (when using ggplots-values). For me around 5 works for the text-size.

I think I'd rather just take this out. Initially, I was thinking we could use ggplot2::theme_set() for any plot settings that overlap between ggplot2 and our settings needs. But we call theme_void() in static_plot() anyway and now that we have the rest of the options setting code I'll take out that part.

For now, you can run set_font_size() at the start of your session to set the sizes globally to something more reasonable.

I don't quite understand the advantages of get_input_text(), what is the advantage of creating a list first and then pasting its x and y argument again?

get_input_text() is a simple helper to get the text name of the x and y inputs, which may or may not be quoted (they are quoted if passed from a wrapper function like animate_left_join()). Because they may be quoted, the make_named_data() is needed to make sure that they are unquoted for the remainder of the function. I included adding the variable names to this list so that in the future I can write something like this

data <- make_named_data(x, y, c(get_input_text(x), get_input_text(y)))

and then data can carry around the data and the names. But I didn't want to break the readability of your code, so the default is to call those elements .$x and .$y.

Currently we pass the dots to the animation-function in the join and set functions, but not to the tidyr animation functions. Are they still in use? If so, should we maybe standardise its usage?

Yup, the join/set functions haven't been updated yet. I was using the tidy family as the example of how the anim_opts argument and anim_options() functions can be used... If all looks good I'll move on to updating those function families as well.