A weight that spreads from a selected point along the surface rather than through space. On a thin slab seeded at the centre of its top face, the top face carries a round falloff while the bottom face, only a tenth of a unit away in a straight line, stays unweighted: the walk has to go round the rim to reach it.
Examples
Every one of these opens in the browser editor, running, with its node graph laid out for you to take apart. Nothing to install and no account needed.
A manifold boolean keeps no primitive attribute, so a colour set per face is lost when a corner is cut away. A primitive ID does survive the boolean, and geo/AttributeCopy matching by that ID brings the colour back onto every face cut from a coloured one. The walls the cutter made have no source face and keep their own colour.
geo/M3DBoolean geo/AttributeCopy geo/AttributeId
A lumpy ball reduced to 5% of its triangles three ways: evenly, keeping more points where an importance attribute says so, and keeping a locked group of points untouched.
geo/Decimate geo/AttributeTransfer geo/AttributeDisplay geo/GroupCreate
A loop that runs once per quad of a plane and writes each quad's number on it. geo/forEachBegin hands the loop one quad at a time, and the nodes in the loop read it by expression: the text takes the quad's ID, the transform takes its centre. geo/forEachEnd gathers what every pass produced.
A mushroom and a shelf bracket, as modelled at the back and turned by geo/PrintOrient at the front, coloured by the overhang that needs support: the turned parts need none. A third bracket may only take the turns kept from geo/PrintDownDirection's arrows.
geo/PrintOrient geo/PrintDownDirection geo/PrintOverhangMeasure
A ball, a T and a cube on its edge, measured for the faces a 3D printer cannot build without support, and shown four ways: how far each face leans, how bad each region is, which region each face is in, and the surfaces a support would hold up.
geo/PrintOverhangMeasure geo/AttributePromote geo/AttributeDisplay geo/Delete
A box with a tube through it, welded into one mesh and never booleaned, which is how such a part arrives from a modeller or in an STL. Both objects are the same solid, before and after geo/M3DResolveOverlaps, wearing a translucent material so the buried surfaces show: the left one carries the tube's wall on through the inside of the box, the right one is a single surface. The volumes beside them say the same thing in numbers.
Create a basic vase for 3D printing with SDF
geo/Circle geo/CopyToPoints geo/SDFBoolean geo/SDFTriangulate geo/SDFTube
Flat text bent onto a cylinder at its own size and engraved into it, with the letters keeping their width all the way round. Switch the imprint profile to RAMP and the same graph makes a raised label.
This shows how to apply different colors on an SDF object
geo/MaterialAttributes geo/SDFBoolean geo/SDFBox geo/SDFSphere
A sphere wired INTO a geo/SDFBuilder and roughened into a rock, by adding noise to the field code/SDFInput reads back.
A line bent into a helix, read as a curve in space and given a thickness: one exact field, with nothing swept and nothing stitched.
geo/SDFCreate geo/SDFOffset geo/PointBuilder
A head printed in clear amber resin, with an opaque skull inside it. The skin and the skull are two regions of one SDF object, joined by a hard union. geo/MaterialAttributes makes the skin transmissive, with an IOR and an amber attenuation colour, and gives the skull a bone colour. The view ray bends into the resin, turns deeper amber the further it travels, and stops on the skull. The light that reaches the skull is not dimmed by the resin around it, and the resin shows the environment, not other objects behind it.
A word extruded into a solid and voxelized into an SDF field, with the bake cached to a .pvol so it only ever happens once. Edit the text to watch the cache go stale and re-bake itself.
A single tooth turned into a ring of ten around a hub, as one field rather than ten objects. Drag the count and watch the gear fill in without the shader being rebuilt.
A threaded rod and the nut it turns in, built as fields instead of a more classic sweep geometry.
geo/PolyNode geo/SDFRevolve geo/SDFBoolean
A six-sided prism spiralled into a fluted column by one node, with no repetition anywhere. Drag the rate and watch it wind up.
The same logo scaled onto the same plate twice: fitted whole on one branch, stretched to fill on the other, with no size typed anywhere.
A part built along Y turned to lie along another object's axis, with a roll, by naming the two axes instead of typing an angle.
Five parts of different sizes laid out twice: as a row, and packed onto a 256 mm plate that is then measured against the build volume.
A sphere cut into Voronoi cells around evenly spread points, with a small gap so every piece stands apart.
geo/VoronoiCells geo/PointRelax geo/Scatter
A thin spherical shell with a Voronoi pattern of holes cut through it, the wire look of a lamp shade.
A sphere broken into the Voronoi cells of evenly spread points. On the left, every cell is a pebble with rounded cut edges. On the right, only the walls between the cells are kept, a foam skeleton of the sphere. Change `smoothness` to go from sharp shards to round pebbles.