The VMS rosettes folio doesn't feel like siege imagery to me, but there are some iconographical elements in siege drawings that relate to the way other things were drawn in the 14th and 15th centuries, so I thought it might be interesting to look at them. I didn't want Marco's discussion of tents to go off-topic, so I thought it might be a good idea to start a separate thread for the broader topic of siege imagery.
To start off...
This is the 7th century siege of Constantinople by the Sassanids/Ava/Slavic forces (fresco in Modovita Monastery) which was painted in 1537.
What it has in common with the VMS rosettes folio is the big round waves around one edge of the city walls (similar to the "big wave" shapes in the VMS rotum top-right) and high mountain escarpments with a castle on a separate "bump" nearby:
Image credit Man vyi, Wikipedia
If you look closely, you will also see long pipes that look like cannons pointing out at the ship in the water. Pipes were used to shoot fire at least before the 12th century.
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The siege of Chandax (Biblioteca Nacional de España). Note the tents, arches, and the "bumpy texture" for the helmets (this was a common way to depict an army wearing helmets):
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Wikipedia from the History of John Skylitzes
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Saddleback portal gate and tents showing the tie-downs (maybe belongs on the tent thread, but I thought it was a good example of a saddleback portal):
Siege of Hennebont (1342, depicted in the 15th century), Jean Froissart, BNF via Wikipedia
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Men dressed as mounds. Not quite like the mounds on the rosette folio (they have holes in the top), but I thought I'd post them, for the record, along with another saddleback portal gate:
Göttingen Codex philos 63 (15th century)