Save

Saves the model using the current file name.

Also see Incremental save for a way to save using incremented version numbers (file01.3dm, file02.3dm, file03.3dm, etc...)

Undo

Reverses the most recent action.

Undo is normally used to reverse edits to objects, but it can also be used to restore the previous selection. So for example, if you are building up a selection and accidentally click somewhere and mess it up, use Undo to get your selection back. Selection undo only works for one step back, after that further undos will switch to undoing geometry edits.

Redo

Reapplies the last action that was undone.

Delete

Deletes or removes an object, or certain portions of an object depending on the selection.

If a whole object is selected, that entire object will be deleted.

If faces of a solid are selected, those faces will be removed.

Control points of a curve can be removed with this command.

If all the edges of a trimming boundary (for example, a hole trimmed in a surface) are selected, then delete can be used to remove that trimming boundary and restore the original underlying surface. This is sometimes referred to as "untrimming".

These tabs on the bottom toolbar control the viewport configuration, switching between the split view or a maximized single view.

Clicking a second time on the Top, Front, or Right tabs will toggle back and forth between the reversed views (Bottom, Back, Left).

These controls in the middle of the bottom toolbar allow for viewing and entering exact numeric data when picking points during a drawing command.

The x,y,z edit box shows the coordinates of the current point under the mouse. The distance edit box shows the distance between the previous picked point and the current point, and the angle box shows the angle of the line formed between the previous picked point and the current point.

Distance constraint can be activated by entering a value in the distance edit box. This will force the next point to be the given distance away from the previous point. This can be used for example when drawing a line to restrict the length of the line to a certain value while allowing it to be oriented freely.

Angle constraint can be activated by entering a value in the angle edit box. This will force the next point to snap to the given angle from the previous point.

If you want to type in an x,y,z coordinate using the keyboard, it is usually not necessary to actually click in the xyz box before typing. Just start typing and your keystrokes will go there automatically.

Clicking on this button allows toggling grid snap on or off. The button will show with an orange highlight when grid snap is enabled. The size of the grid can be changed under Options / Grid.

Clicking on this button toggles straight snap on or off. The button will show with an orange highlight when straight snap is enabled. Different options for straight snap can be set under Options / Snaps. By default the snap angle is set to 90 degrees, the default can be changed under options. It is also possible to use Angle constraint to define a custom snap angle that stays in effect for just one pick, see XYZ / Distance / Angle above. Snapping to too many angles by default can get in the way of doing freeform drawing, so it can be a good idea to leave the default to 90 and use Angle constraint when necessary to get other angles.

Clicking on this button toggles object snap on or off. The button will show with an orange highlight when object snap is enabled. When you move over this button, an arrow will appear above it, and you can use that to show a menu that allows enabling or disabling specific types of object snaps. It is recommended to leave all the snap types enabled, and instead disable or enable Object Snap completely by clicking on the main button for it.

Options

Opens the Options dialog which allows for changing various options for how MoI works.

Also see Shortcut keys

Help

Launches the help file. When moving over the help button, you can use the arrow that appears above it to open the About dialog to show version information.

Full Screen

This allows for MoI to switch back and forth from full screen mode. When full screen mode is enabled, MoI's window will expand past the Windows system task bar to give you a larger working area. This button only appears when MoI's window is maximized.