Inference and snapping — ModelCraft help

While a drawing or editing tool is working, ModelCraft looks at what is under the pointer and snaps to the most useful thing nearby. A marker shows what it found and the tip at the bottom left names it.

Markers and tips

Tip	Marker	Snaps to
Endpoint	Green circle	The end of an edge
Midpoint	Cyan circle	The middle of an edge
Guide point	Grey	A guide point left by the tape measure
Origin	Ochre	Where the red, green and blue axes meet
On red axis / On green axis / On blue axis	A line in that color	A line from your start point along that direction
Parallel to edge / Perpendicular to edge	Magenta line	A line from your start point parallel or perpendicular to the remembered edge (see below)
Locked	Magenta line	A direction you locked with an arrow key or `⇧Shift`
On edge	Red square	Anywhere along an edge
On guide	Grey	Anywhere along a guide line
On face	Blue diamond	Anywhere on a face
On plane	none	The plane you started on, when the pointer is over empty space
On the ground	none	The ground (the red-green plane), when nothing else is there

When an axis line from your start point crosses an edge or guide, ModelCraft snaps to the crossing and the tip names both, such as "On red axis, on edge".

Which snap wins

Points within about 12 pixels: endpoints first, then guide points, midpoints and the origin.
Directions from the start point: the red, green and blue axes, and parallel or perpendicular to the remembered edge.
On an edge or a guide line.
On a face.
The drawing plane, or the ground.

Things hidden behind a face never snap. Orbit so you can see the point you want.

Parallel and perpendicular

ModelCraft remembers the last edge the pointer passed over before your first click. Starting on a corner or on an edge counts as passing over that edge. Once the tool is working, other edges you hover do not replace it.

To draw a line parallel to an existing edge:

Press LL and hover the edge you want to match.
Move to the start point, without crossing other edges on the way if you can, and click.
Move in the direction parallel to that edge. The line turns magenta and the tip says "Parallel to edge". Perpendicular works the same way, within the plane you are drawing on.

If the wrong edge was remembered, press EscEsc, hover the right edge, and start again.

Lock a direction

After the first click of a tool, you can keep the next point on one line:

Key	Locks to
`→→`	The red axis
`←←`	The green axis
`↑↑`	The blue axis (straight up)
`↓↓`	Parallel to the remembered edge (see above)

Press the same arrow again to unlock. The status bar says "Locked to the red axis. Press the same arrow to unlock."

While locked, the point slides along the line toward wherever the pointer is, and still lines up with points you hover: hover the corner of another box to draw a line along red exactly as far as that corner.

⇧Shift locks whatever direction you are snapped to right now (an axis, or parallel), for as long as you hold it. Let go to unlock.

Locks work in Line, Rectangle, Circle, Polygon, Move, Scale and Tape. Before the first click, the arrow keys orbit the view instead.

Inside a group

While you edit inside a group or component, the axes are the group's own axes (they move with it, and turn with it if it was rotated). Snaps still find points and edges outside the group, so you can line things up with the rest of the model.