Remember you can hide the edge of a morph.
Then if this joins a wall and the surfaces are in line and they have the same surface material then there will be no joining line in 3D.
The floor plan representation is another matter.
You can't turn the lines off in plan but you can make them match what they touch or place a whit line over the top to hide the joins.
In section if the morph has the same sectional fill (Building Material) as what it is touching then they should blend with no join.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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