Helper for testthat testing. — expect_known

Gets the current scene using scene3d, and compares the result to a saved value, optionally closing the window afterwards.

Usage

expect_known_scene(name, 
                   close = TRUE, 
                   file = paste0("testdata/", name, ".rds"),
                   ...)

Arguments

name: By default, the base name of the file to save results in. Not used if file is specified.
close: Whether to close the rgl window after the comparison.
file: The file in which to save the result.
...: Other arguments which will be passed to expect_known_value.

Details

This function uses expect_known_value to save a representation of the scene. During the comparison, the scene is modified so that non-reproducible aspects are standardized or omitted:

object ids are changed to start at 1.
system-specific font names and texture names are deleted.
the window is shifted to the top left of the screen.

Calls to expect_known_scene() enable testthat::local_edition(2) for the duration of the call, so it will work in testthat “3rd edition”.

Value

A value describing the changes to the saved object, suitable for use in test_that().

Examples

if (FALSE) { # \dontrun{
# These lines can be included in testthat::test_that() code.
plot3d(1:10, 1:10, 1:10)
expect_known_scene("plot")
} # }