Navigation: orbit about the point under the cursor, zoom toward it, presets in the display menu

An orbit turns about the model point under the press (the pick ray's
first hit on the plot, the mesh or the design), or the centre of what is
drawn when it starts on empty space, keeps that point still on screen and
marks it while orbiting. The wheel and a pinch zoom toward the point
under the cursor; the wheel's delta is read as it arrives, so a notch
zooms in full in orthographic and perspective views alike (#273).

Mouse presets and reverse zoom come from SolidCraft (prefs.rs NavPreset,
NAV_PRESETS; MIT OR Apache-2.0): FieldCraft's own (left drag per the
navigation bar) stays the default, Ctrl + left drag from empty space
orbits in every preset. They are chosen in the display menu, settable
with ui.set and kept in prefs.json beside recent.json (the browser build
keeps them for the page's run); an older prefs.json still loads.

Fixes #262, fixes #273.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

docs/control-protocol.md

@@ -42,7 +42,7 @@ commands (files, undo, `model.info`) leave the ribbon where it is.
 | Method | Params | Notes |
 |---|---|---|
 | `ui.inspect` | — | view settings (`ui`), camera, viewport rect (points), renderer (`gpu`/`cpu`) and adapter, open command form, status bar, node and element counts, the results display (`results`: what the `results.*` commands reply: view, `stale`, contour range, modes), the probed node (`probe`), `solve` (the title bar's Solve: `enabled`, and `unavailable` as `ui.toolbar`'s entries give it, listing everything `solve.run` misses), `busy` (the background job: a file opening, a solve, a mesher run from its form by a click on OK), `prompt` (`{"unsaved": path}`, `{"design": path}` (a design of another part opened over a meshed or defined model), `"recover"`, `"samples"`), `recent` (recent files), `selected` (the browser's selected definition), `browser` (each top-level browser node's setup state: `[{node, state, tip, add}]`, `state` `done`, `next`, `blocked` (⚠: its command cannot run yet; `tip` says what it needs and where), `todo`, `optional` or null for nodes that are no setup stage, `add` its ghost rows `{stage, label, command, status}`; a ghost row's region is `layout`'s `browser/add/<stage>`), `nav` (the left-drag mode), `layout` (each region of the window drawn last frame as `[x, y, w, h]` in points: `app_bar`, `ribbon`, `workspace_switcher`, `document_tab`, `app_bar:<action>`, `browser`, `viewport`, `nav_bar`, `axis_view`, `selection_bar`, `legend` (while results are shown), `context`, `command_line`, `timeline`, `toolbar_dropdown`, `palette`), version |
-| `ui.set` | any view setting: `style` (`shaded_edges`, `shaded`, `wireframe`), `show_nodes`, `show_geometry`, `show_mesh`, `show_loads` (boundary condition and load symbols), `show_interactions` (reference points, couplings, rigid walls), `perspective`, `dark`, `show_tree` (the browser), `show_timeline`, `workspace` (`prepare`, `model`, `analysis`, `results`), `tab` (the toolbar tab: `geometry`, `mesh`, `properties`, `assembly`, `steps`, `loads`, `interactions`, `solve`, `results`, `tools`; a tab of another workspace brings that workspace), `palette` (the command search open), `menu` (the open menu: `file`, `help`, `workspace`, `view`, `more`, or a panel's drop-down as `<tab>/<panel>` such as `mesh/Tet`; `null` closes it) | an unknown setting or value is an error; returns the settings |
+| `ui.set` | any view setting: `style` (`shaded_edges`, `shaded`, `wireframe`), `show_nodes`, `show_geometry`, `show_mesh`, `show_loads` (boundary condition and load symbols), `show_interactions` (reference points, couplings, rigid walls), `perspective`, `dark`, `show_tree` (the browser), `show_timeline`, `nav_preset` (the mouse navigation: `fieldcraft`, `fusion`, `solidworks`, `inventor`, `alias`, `tinkercad`, `openscad`; an unknown id acts as `fieldcraft`) and `reverse_zoom` (both remembered per user), `workspace` (`prepare`, `model`, `analysis`, `results`), `tab` (the toolbar tab: `geometry`, `mesh`, `properties`, `assembly`, `steps`, `loads`, `interactions`, `solve`, `results`, `tools`; a tab of another workspace brings that workspace), `palette` (the command search open), `menu` (the open menu: `file`, `help`, `workspace`, `view`, `more`, or a panel's drop-down as `<tab>/<panel>` such as `mesh/Tet`; `null` closes it) | an unknown setting or value is an error; returns the settings |
 | `ui.view` | `view`: `front`, `back`, `left`, `right`, `top`, `bottom`, `iso`, `home` (iso and fit), `fit` | every view frames the model as drawn (the deformed shape and the setup's symbols included) in the part of the viewport the overlays (`layout`'s `legend`, `selection_bar`, `axis_view`, `nav_bar`) leave free; `fit` keeps the direction of view. Opening another model, sample or design frames it in the home view (the same design opened again after an edit keeps the camera), and results that come up with part of the model out of sight are framed. Returns the camera |
 | `ui.camera` | `yaw`, `pitch` (degrees), `distance?` (model units) | turns the camera to any orientation about its target: `yaw` about Z (0 looks along +Y, the front view; −45 is the iso view's, −90 the right view's), `pitch` the elevation above the XY plane; `distance` moves the eye (the zoom of an orthographic view). Angles must be finite and the distance above 0: the yaw is wrapped, the pitch clamped to ±90 and the distance to 0.001–10⁹; anything else is an error. A sequence of calls orbits smoothly. Returns the camera (`ui.inspect`'s, angles in radians) |
 | `ui.toolbar` | — | the ribbon: `workspace`, `workspaces`, `tab`, `tabs` (the workspace's), `menu` (the open menu), `panels` (each panel label's `menu` key and `rect`), and every catalogue entry (docs/features.md) with `id`, `label`, `tab`, `panel`, `command` (null while coming soon), `more` (its related commands), `coming_soon` (the milestone, or null), `enabled` (false while coming soon or while its command misses what it needs), `unavailable` (null, or what its command misses: `reason`, the tooltip's lines such as "Needs a material — Properties › Material", and `missing`, each with `requirement`, `what`, `provider` (the command that provides it) and `place` (its toolbar entry)), `fit` — `full` (a button), `collapsed` (its panel is one button), `more` (its panel is in the » menu) or `menu` (in its panel's drop-down) — and `rect` (screen points, last frame, on the shown tab; for `menu` entries the row while the drop-down is open) |
@@ -54,8 +54,8 @@ commands (files, undo, `model.info`) leave the ribbon where it is.
 | `ui.dialog` | `params?` (JSON object, fills the form), `use_selection?`, `run?`, `submit?`, `cancel?` | drives the open command form, in that order; `use_selection` is the form's Target row (see [Selection](#selection)); `run` returns the command's result and closes the form on success; `submit` is the form's OK button: a mesher that would replace a body's mesh first asks (`prompt` `replace_mesh`, with the question and what else goes: sets listing the old labels, solved results), and meshers run in the background (`busy`); a form opened by another form's **Create …** button (a reference field with nothing to pick) goes back to that form on `run` (with the new item picked) or `cancel` |
 | `ui.click` | `x`, `y` (screen points), `button?`: `left`/`right`/`middle`, `shift?`, `ctrl?`, `alt?`, `double?` | real pointer input; in the viewport a click selects what is under it (Shift adds, Ctrl/Cmd adds or removes, a click on nothing clears the selection), and a click on a results plot also probes the nearest node of the face under it (`solve.probe`; `ui.inspect` shows the values) |
 | `ui.move` | `x`, `y` | |
-| `ui.drag` | `x0`, `y0`, `x1`, `y1`, `button?`, `shift?`, `ctrl?`, `steps?` (1–200) | press, move, release: in the viewport a left drag orbits (with box selection on, it selects the visible nodes, element faces or elements in the box), a right or middle drag (or Shift + left) pans |
-| `ui.scroll` | `x`, `y`, `delta?` (wheel lines, −100–100; positive zooms in) | zooms at the point |
+| `ui.drag` | `x0`, `y0`, `x1`, `y1`, `button?`, `shift?`, `ctrl?`, `steps?` (1–200) | press, move, release: in the viewport the drag does what the navigation preset (`ui.set {nav_preset}`) binds; by default a left drag orbits about the model point under the press, or the centre of what is drawn from empty space (with box selection on, it selects the visible nodes, element faces or elements in the box; Ctrl + left from empty space still orbits), a right or middle drag (or Shift + left) pans |
+| `ui.scroll` | `x`, `y`, `delta?` (wheel lines, −100–100; positive zooms in) | zooms toward the model point under `x`, `y` (the point at the target's depth over empty space), by the same factor per line in orthographic and perspective views; `ui.set {reverse_zoom}` turns it the other way |
 | `ui.key` | `key` (egui key name, `Enter`, `Escape`…), `cmd?`, `shift?` | `F` over the viewport frames the model; `Escape` clears the selection (and then cancels an open form) |
 | `ui.text` | `text` | typed text (into the focused field) |
 | `ui.drop` | `paths`: 1–16 file paths | drops the files on the window: the next frame opens them as a drop from the file manager does, and as a file picked in the Open dialog does (a `.fieldcraft` model, a `.solidcraft` design, a `.3mf` tagged mesh; `ui.inspect`'s `busy` while they open). The native picker cannot be driven over the channel; this is the same route |