The public 3D and Materials panel options list Depth, Twist, Taper and Cap
for every 3D type; Inflate had only Depth.
- Twist (0° to 360°) and Taper (1–100 %) turn and scale the back about the
shape's centre, as Extrude & Bevel's do: a puffed back is turned and
lowered in proportion, and the sides follow in slices.
- Cap: Solid closes the back; Hollow leaves it off, so the inflated front is
a shell open behind. The documentation doesn't say what Cap means for
Inflate; this reading is stated in docs/three-d.md.
- The dialog's Object tab shows them in the documented order (Depth, Twist,
Taper, Cap), then Volume and Both sides.
At 0 % volume a twisted, tapered Inflate has the extrusion's outline from
every side (tested).
A twisted, tapered, hollow Inflate draws on the canvas exactly as it
exports, and expands to faces with their own ids (tested). ROADMAP and the
parity pages list the new options; the 3D score stays at ~25 %.
The public 3D and Materials panel options give Twist as up to 360°; it took
-360° to 360°. Values beyond either end now hold at that end (the effect is
a day old, so only fresh files carry a negative twist).
Extrude & Bevel, Inflate and Rotate sampled every curve at sixteen points and
refused a shape past 1,024 points, about 64 curves: outlined words reached
that quickly, and Rotate refused them although it only turns the outline.
- Each curve takes as many straight pieces as keep it within 1/2000 of the
shape's size (at least 0.05 pt), by Wang's bound: 1 to 32.
- Extrude & Bevel and Inflate take up to 2,048 points, Rotate 65,536.
- Inflate's distance and crossing tests use a bucketed edge index, and
cells no edge crosses skip clipping: about 80 ms at 2,000 points (it was
over 600 ms with the old search; 95 ms at the old 1,024-point limit).
Revolve's own sampling is unchanged.
Bevel Shape, Space, Bevel Inside, Bevel both sides and Presets, as the public 3D and Materials panel
options page names them. The 3D effects' error messages get rows in the twelve complete catalogs.
The three 3D types besides Revolve, as live effects in the three-d crate,
drawn as shaded vector faces by the canvas, SVG/PDF export and Expand
Appearance alike, from the public 3D and Materials documentation:
- Extrude & Bevel: depth (0-2000 pt), twist, taper, solid or hollow caps,
and bevels in six original cross-sections (classic, rounded, cove, step,
ogee) with width, height, repeat, spacing, inside and both sides.
- Inflate: the shape as a membrane under pressure (a Poisson solve held at
zero along the outline and holes), so it rises vertically from the edge
and rounds without creases; volume, depth and both sides. Steep cells
near the outline are refined without cracks.
- Rotate: every fill and stroke turned in 3D and shaded as one plane.
All three share Revolve's view and lighting parameters, the rotation and
light gizmos (turning about the art's centre) and a dialog with Object,
Rotation and Lighting tabs, with Position presets (Front ... Isometric
Bottom, our own values). An object takes one 3D effect. Inflate cuts the
grid cells that straddle a hole's edge with pathops, hence the new
pathops -> three-d layer order.
Docs: docs/three-d.md, mcp.md, and the 3D rows of the parity docs.
Ayberk A.
bflatastic