Flow (Loft) — Multi-Profile 3D Surface Generation
Flow generates a smooth 3D surface that blends through two or more flat 2D profile shapes, each placed at a different elevation. Unlike Sweep — which extrudes one profile along a path — Flow interpolates between profiles of different sizes and shapes, producing organic transitions ideal for sculptural landforms, vaulted roof sections, and freeform garden structures.
To use Flow, draw two or more flat 2D shapes (circles, polygons, or any closed outline) and set each to a different elevation in the Inspector. Then activate the Flow tool, click the profiles in order, and press Enter. The loft surface is generated immediately and becomes a standard mesh that can be further edited in the Mesh Editor.
The Smoothness parameter controls how tightly the surface follows each profile — low values create more angular transitions, high values produce smoother curves. The Closed Loop option connects the last profile back to the first to form a continuous tube or ring.
Draw and position the profile shapes
Before activating Flow, prepare the profiles in the 2D or 3D editor:
1. Draw two or more closed 2D shapes — circles, polygons, rectangles, or custom bezier outlines. Each shape will become a cross-section of the loft. 2. Set a different elevation on each shape using the Inspector (Z / Elevation field). Profiles at the same elevation produce a flat, degenerate loft. 3. Profiles can be different sizes and shapes — Flow interpolates between them. For example, a large circle at ground level transitioning to a small square at the top creates a chimney-like form.
Profile placement in the plan view determines the horizontal position of each cross-section. Stagger them horizontally if you want the loft to lean or curve sideways as it rises.
Start with just two profiles to understand the tool, then add a third intermediate profile to control the shape of the transition.
Pick profiles and generate the loft
1. Click Flow in the 3D editor toolbar (or search 'Flow' in the command palette) 2. Click each profile in order — the order determines the direction of the loft from bottom to top (or along any axis). Each picked profile highlights to confirm selection. A minimum of 2 profiles is required. 3. To deselect a profile, click it again. To reorder, deselect all and re-pick in the desired order. 4. Press Enter to generate the loft. The 3D surface appears immediately.
The resulting object is a standard mesh entity. It can be moved, scaled, and entered in the Mesh Editor for further shaping.
Common garden design uses:
- Organic landforms and sculptural earth mounds
- Vaulted roof sections and canopy forms
- Transitional columns that change profile from base to capital
- Custom planters with tapered or compound profiles
Profile order matters — picking bottom-to-top produces an upright loft; picking in a different order creates a twisted or inverted form. If the result looks wrong, undo and re-pick in the correct sequence.
Adjust Smoothness and Closed Loop
Two parameters appear in the Flow tool panel:
Smoothness (0–100%) Controls how smoothly the surface transitions between profiles.
- 0% — angular, faceted transitions. Each profile cross-section is sharp.
- 50% — balanced interpolation, suitable for most organic forms.
- 100% — maximum smoothing. The surface rounds aggressively between profiles, which can cause it to bulge outward between tightly spaced profiles.
Adjust smoothness before pressing Enter to preview the effect on the generated shape.
Closed Loop When enabled, the loft connects the last profile back to the first, forming a continuous closed surface — useful for ring-shaped or toroidal garden structures. When disabled (default), the loft has open top and bottom faces.
Pick profiles from bottom to top for a natural upright loft. Picking in a different order produces a twisted or inverted form.
Set Smoothness and Closed Loop, then confirm
Before pressing Enter, adjust the two parameters in the Flow tool panel. Smoothness (0–100%) controls how curved the interpolation is between profiles: 0% gives angular, faceted transitions; 50% suits most organic forms; 100% produces maximum rounding, which can cause the surface to bulge outward between tightly spaced profiles. Closed Loop connects the last profile back to the first, forming a continuous closed surface useful for ring-shaped or toroidal structures — leave it off for open-ended forms. When ready, press Enter or click Apply to generate the loft. The parametric surface appears immediately in the viewport.
Edit sections in 3D after generation
Select the loft object and toggle Edit profile in 3D in the Inspector or tool sidebar. Section markers (small squares) appear above each profile in the viewport — these let you manage the loft's cross-sections directly. Drag any bezier control handle to reshape that section's silhouette; the surface regenerates live as you drag. To remove a section, Alt+click its marker — the loft must keep at least two sections and will refuse to drop below that minimum. To insert a new section between two existing ones, Shift+click between their markers; Flow duplicates the nearer section and places it at the midpoint elevation automatically.
Use the section markers to add detail progressively — start with two sections to establish the overall form, then Shift+click to insert intermediate sections and refine the shape.
Keyboard Shortcuts
| Key | Action |
|---|---|
| Enter | Confirm and generate the loft |
| Click | Pick or deselect a profile |
| Alt + Click marker | Remove a section (in edit mode) |
| Shift + Click between markers | Insert a section between two existing ones |
| Esc | Cancel and exit the Flow tool |
Frequently Asked Questions
What is the difference between Flow and Sweep?
Sweep extrudes a single profile along a drawn path, producing a consistent cross-section throughout the entire length. Flow blends between multiple profiles that can have different shapes and sizes — it does not follow a drawn path but instead interpolates between cross-sections placed at different elevations and positions. Use Sweep for railings, edging, and uniform extrusions; use Flow for organic forms that taper, flare, or transition between different shapes.
Can I add or remove sections after generating the loft?
Yes. Select the loft, toggle Edit profile in 3D, then Alt+click a section marker to remove it (the loft requires at least two sections and will not drop below that minimum). To insert a new section, Shift+click between two existing section markers — Flow places a duplicate section at the midpoint elevation automatically. Changes regenerate the surface immediately.
Can I use 3D objects or extruded shapes as profiles?
No — Flow only accepts flat 2D shapes as profiles. Circles, rectangles, polygons, and closed bezier curves all work. Extruded shapes, boxes, spheres, and other 3D volumes are not valid profiles and are ignored when clicked during the picking step. Check the Inspector to confirm a shape has no extrusion height before selecting it as a profile.
How many profiles can I use?
There is no hard upper limit. In practice, 2–5 profiles produce manageable parametric results. More profiles give finer control over the shape. For complex organic forms, consider using 3–4 profiles to establish the overall silhouette, then insert intermediate sections to refine the surface.
Why does the loft bulge outward between my profiles?
High Smoothness values cause the surface to arc outward between profiles, especially when profiles are placed close together vertically. Lower the Smoothness slider toward 0% to reduce the bulge, or insert an additional intermediate section between the two profiles to give the interpolation a tighter anchor point.
Common garden uses for Flow: natural earth mounds and domes (large circle at ground, small circle at peak), tapered columns and planters (wide base, narrow top), vaulted canopy sections (flat rectangle at ground level lofting to an arched profile above), and toroidal ring structures using Closed Loop.