Quoting Mirai Warren <the.future.comes...@gmail.com>:
> What I want to do is similar to the "Duplicate Continue" plugin, but
> instead of duplicating the entire frame, only the current layer would
> be duplicated and added to the layer stack of the following frame, and
> a new frame would not be created. What I tried was to switch out
> gap_lib_image_file_copy with gap_layer_copy_to_image but I don't know
> how to get the current layer as the source layer.
The short answer:
source_layer_id = gimp_image_get_active_layer(source_image_id)
You should be aware, however, of how GAP determines the "active layer"
for each frame; it varies depending upon the settings of the
"AL-Tracking" mode specified in the VCR Navigator (this mode being one
of "by layername", "by layerstack position", or "off").
I would also point out that the task you are attempting can be
accomplished using GAP's Onionskin capabilities. The configuration
options for onionskinning are described in the following document:
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