replace show/hide links with icons
add checked/unchecked checkbox and radio button
fix bug with rotation in plane where green line stays displayed
lock point where dragged constraint
remove toolbar icons for sketch in 3d, add View -> Align to Workplane

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rounding, as a special group
associative entities from solid model, as a special group
better level of detail
some kind of import
faster triangulation
loop detection
IGES export
incremental regen of entities