Why such a default for IMAGES_LIB_DIR?

[Yar Tikhiy]

Hi there,

I found that building documents outside the doc tree requires
setting, besides DOC_PREFIX and LANGCODE, IMAGES_LIB_DIR in case
the documents use, say, callout images.  This is because the default
for IMAGES_LIB_DIR is as follows in doc.images.mk:

    IMAGES_LIB_DIR?=        ${.CURDIR}/../../../share/images

Is there a reason for the default not to be ${DOC_PREFIX}/share/images
instead?  Are there any alternative doc sub-trees, like src/release, that
use their own images instead of those from the main doc tree, and so they
benefit from the current default?  Excuse me for the probably lame
questions...  Thanks.

-- 
Yar