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744 Chapter 21: User Interface
Ar c Rot ate Fly out
Activate a Perspective or orthographic viewport. >
Viewport Navigation controls > Arc Rotate flyout
Keyboard > Alt +mid dle mouse button
The Arc Rotate flyout displays the Arc Rotate
button, the Arc Rotate Selected button, and the
Arc Rotate Sub-Object button. U se these to rotate
your viewpoint around the view.
For more information on these tools, see Arc
Ro tate, Arc Rotate Selected, Ar c Rotate Sub-Object
(page 3–744).
Arc Rotate, Arc Rotate Selected,
Arc Rotate Sub-Object
Activate a Perspective or orthographic viewport. >
Viewport Navigation controls > Arc Rotate flyout
Keyboard > Alt +mid dle mouse button
The Arc Rotate buttons, on the Arc Rotate flyout
(page 3–744), spin the viewpoint freely around a
center.
Three Arc Rotate variants are available: Arc Rotate,
Arc Rotate Selected, and Arc Rotate Sub-Object.
Arc Rotate is modal (page 3–973): it remains active
until you r ight-click or choose another command.
Arc Rotate respects Angle Snap (page 2–37).
If you turn on Angle Snap, the Arc Rotate mouse
pointer displays a magnet, and the rotation snaps
by the Viewport Arc Rotate Snap Angle setting.
Arc Rotation used a hidden “virtual target” as
the point which is used for the center of rotation.
Holding the
Ctrl keydowninArcRotatemode
has a special behavior: It performs a rotation
of the scene around the screen’s X and Y axis
(at the position of the vir tu al target). Move the
mouse horizontally yields rotation around world
coordinates referential Z axis. User moves the
mouse vertically yields rotation around screen
coordinates referential X axis. This differs from
standard Arc Rotate, when horizontal mouse
movement rotates around screen coordina tes
referential Y axis.
Procedures
To use Arc Rotate:
1.
Activate a Perspective or orthographic
view por t.
2. ClickanyofthethreeArcRotatebuttons.
A view rotation “trackball” is displayed as
ayellowcirclewithhandlesplacedatthe
quadrant points.
3. Drag the mouse on and around the trackball to
produce different types of view rotations. The
cursorchangestoindicatewhattypeofrotation
you are about to perform.
• Drag the handles to keep the rotation either
horizontal or vertical. Drag horizontally on
thesidehandles,orverticallyonthetopor
bottom handle.
• Draginsidethetrackballtorotatetheview
freely within the viewport. The f ree rotation
continues whi le dragg ing even if the cursor
crosses outside the t rackball.
• Drag outside the trackball to rotate the v iew
about t he depth axis that is perpendicular
to the screen. When the cursor crosses
inside the trackball during dragging, free