Create a knitr chunk hook for live mypaint rendering

The returned hook opens mypaint_device() before chunk evaluation and injects the generated PNG files afterward. This avoids knitr's normal plot replay path, which does not preserve device-local style changes such as set_hand() and set_brush().

Usage

knitr_mypaint_hook(...)

Arguments

...

Default arguments passed through to mypaint_device() when the hook opens a device. Chunk-specific overrides can be supplied in the chunk option mypaint.args as a named list. Because these arguments are applied when the device opens, use this hook or mypaint.args to set chunk defaults; set_brush() and set_hand() still work within the chunk after the device is open.

Value

A function suitable for knitr::knit_hooks$set().

Details

Register it with knitr::knit_hooks$set(mypaint = knitr_mypaint_hook(...)) and then enable it for chunks with mypaint = TRUE. Chunks should also set fig.keep = "none" and fig.ext = "png". If a chunk explicitly sets dev=, the hook is skipped and knitr's normal device handling is used.

Examples

if (requireNamespace("knitr", quietly = TRUE)) {
  hook <- knitr_mypaint_hook(brush = "deevad/2B_pencil")
  print(is.function(hook))
}
#> [1] TRUE