Householder, interested,
Did the Buddha discourage antropomorphic representations of himself?
Not so explicite, but tendency to encouragements on reminders... image of him?
Ven. Ananda Thera once desired to keep a reminder of the Buddha at the monastery, while the Lord Buddha went into the lands, for encouragement of all in his absence, and asked the Buddha in relation of this. While the Buddha remarked that certain memorials of a Buddha while alive are not proper, he allowed to plant a Bodhi-tree one that occation.
"Not proper when alive..." does easy allow the thought that an image (after death) as encouragement and to increase faith, is approved by the Buddha. Now what kinds are there?
Maybe quoting the passage later...oh here
Kalingabodhi-Jataka (Kāliṅgabodhijātakaṃ)
..."This monastery, Sir, is left unprovided while the Tathāgata goes on pilgrimage, and there is no place for the people to do reverence by offering fragrant wreaths and garlands. Will you be so kind, Sir, as to tell the Tathāgata of this matter, and learn from him whether or no it is possible to find a place for this purpose." The other, nothing loth, did so, asking, "How many shrines are there?" —"Three, Ānanda." —"Which are they?" —"Shrines for a relic of the body, a relic of use or wear, a relic of memorial [202]" —"Can a shrine be made, Sir, during your life?" —"No, Ānanda, not a body-shrine; that kind is made when a Buddha enters Nirvāna. A shrine of memorial is improper because the connection depends on the imagination only.(?) But the great bo-tree used by the Buddhas is fit for a shrine, be they alive or be they dead." —"Sir, while you are away on pilgrimage the great monastery of Jetavana °° is unprotected, and the people have no place where they can show their reverence. Shall I plant a seed of the great bo-tree before the gateway of Jetavana?" —"By all means so do, Ānanda, and that shall be as it were an abiding place for me."...
202: See Hardy, Eastern Monachism, 216 f. The last class is said to be images of the Buddha. (similar in German translations)
My person also remembers, that in regard of not allowed to carry and draw pictures, images of humans, for monks, the commentary, at least, report that aside of samvega increasing, images of the Buddha are allowed.
The often ignored commentary, "historical" reports at least, of serious source, whould surely give much detail. There are even guidlines how and where to put (direction...).
Shrine should be understood as memorial image.
More on general reason why such "forms" is found in the Maha Parinibbana Sutta (DN16)
Vandāmi bhante cetiyaṃ, sabbaṃ sabbattha ṭhāne, supatiṭṭhitaṃ sārīraṅka-dhātuṃ, mahā-bodhiṃ buddha-rūpaṃ, sakkāratthaṃ.
I revere every stupa established in every place, every Relic of the Buddha's body, every Great Bodhi tree, every Buddha image that is an object of veneration.
The tendencies in Vinaya are generally strong against subha, but allow asuhba images. See also general comments on Buddhist Art here. The strong attachment to form, by humans, would also explain the Dhammic reason behind the rules.
Further additions, edits and discussion on it can be found here: [Q&A] Buddha-images are allowed by the Buddha (at least by monks)?, in the Open-Vihara.
(Note that this is not given for trade, exchange, stacks, entertainment and akusala deeds, but as a share of merits and continue such for release)