Build the ViewCube out into a full navigation widget:
- Compass ring painted in the cube's ground plane (z = base) so it
reads as a ground compass and foreshortens with the view.
- N/E/S/W cardinals painted flat onto the ring band; clicking one snaps
to that side elevation. Added S/W glyphs to the bitmap atlas.
- Home button (top-down view), roll arrows (90° roll about the view
axis), and four nudge triangles (90° tip/spin) as SVG iced controls
laid out around the cube. New home.svg.
- WCS / named-UCS selector under the cube, switching the active UCS.
The cube hit area now shares one stack with the control buttons, so a
click on a button is caught by the button while a click on the cube
falls through. Face clicks snap to the highlighted region rather than a
cursor position the viewport's move handler can overwrite.
Camera gains home_view / roll_by / nudge_90; floating viewports drive
the same ops through mutate_active_viewport_camera, which re-encodes the
result to the stored view direction + twist.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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