- Gradients: the middle colour sits (horizon - 0.5) viewport widths from the
centre and blends over height viewport heights each side; two colours
blend over a viewport height each side.
- Image backgrounds: offset in device pixels (right, down), negative scale
mirrors, fitted with aspect ratio covers the viewport; the dialog keeps an
image's offset and scale.
- Layouts: a model-space view restored on a sheet asks for the viewport,
enters it and gives it the view's camera, background and visual style;
inside a viewport the view goes there; a paper-space view's background is
kept on the sheet viewport but not drawn; floating viewports draw their
background.
- Background objects no view or viewport uses any more are erased; a view
without a background restored where the viewport already is leaves the
viewport's background.
- The viewport's named visual style (Realistic, ...) shows by name and the
render-mode picker records its style on the viewport record.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>