Use evaluate 1.0.0

[hadley]

Including new trim_intermediates_plot() function.

Although now that I look closely at this I notice that rgl provides a is_low_change() method so that this might be a breaking change, and I need to consider this in evaluate.

[yihui]

Confirmed this is a breaking change for rgl, as you suspected.

rgl registers is_low_change.rglRecordedplot (and imports is_low_change from knitr):

is_low_change.rglRecordedplot <- function(p1, p2) {
  inherits(p2, "rglRecordedplot") && p1$plotnum == p2$plotnum
}

It discriminates 3D scenes by plotnum, not by display list. The current merge_low_plot dispatches through the is_low_change generic, so rgl's method is honored.

evaluate::trim_intermediate_plots (checked against evaluate 1.0.5) bypasses that path entirely:

1. It is not a generic and never calls is_low_change, so is_low_change.rglRecordedplot becomes dead code.
2. It gates on is.recordedplot(), i.e. inherits(x, "recordedplot"). rgl objects are class rglRecordedplot, not recordedplot, so they aren't even considered — rgl plots would silently lose intermediate-plot trimming.

Before merging, evaluate would need an extension point equivalent to is_low_change (so rgl can hook in), or knitr should retain the generic as a shim for non-base-graphics plots. Otherwise this needs a coordinated rgl release. Holding until the rgl path is resolved.

[yihui]

Closing — as noted above, this would drop the is_low_change generic that rgl extends. Keeping it in knitr for now. Thanks @hadley! Happy to take a new PR down the line if evaluate grows an extension point for this (or the rgl side gets sorted).