What it does
Lower stored point heights to prepare a valley profile along a directed network. Each point can be pulled down by a downstream neighbour, with an allowed rise supplied by the cost field.
Choose the stored height name in Value name, then connect the allowed rise to Downstream cost. The cost is read for each directed link, with the current point upstream and its neighbour downstream. Run Output in Pass; the named value must already exist at both ends for a link to constrain the result.
Start with few Hops, which are rounds that let the constraint reach further through the network. Increase them only when the profile needs to follow more distant neighbours. Only selected points receive the final values, though other points can still influence them.
Inputs and outputs
| Name | Type | Default | What it changes |
|---|---|---|---|
| Inputs | |||
| Which points | Point selector | The points whose stored values are updated; other points still participate. | |
| Downstream cost | Density | The allowed rise above the downstream value for each directed link. | |
| Settings | |||
| Value name | Text | level | The existing named point value to lower. |
| Hops | Integer | 8 · 1–1024 | More rounds carry downstream constraints further and increase construction work. |
| Output | |||
| Output | Point action | The grading action to run in a Pass. | |
Good to know
Orient the links before grading
Undirected links do not constrain the heights; two-way links constrain both directions. Check the network direction if the profile stays unchanged.
Keep the allowed rise meaningful
Negative costs are treated as zero. A non-finite cost leaves that link unconstrained, so check the cost field before increasing Hops.