HopperGroup

HopperGroup is a Grasshopper plugin that automatically manages group membership when objects are dragged on the canvas.

aectooling by tomoS

Features

• Adds dragged objects to the innermost Grasshopper group whose visual boundary contains the object center.
• Removes objects from a group only after the object center leaves that group beyond the configured exit buffer.
• Repairs nested groups by making the smallest contained group a direct child of the next larger containing group.
• Provides manual refresh and optional debug logging.
• Marks cached group regions dirty when groups are created or deleted.

Compatibility

• Rhino 8 / Grasshopper.
• Current build targets: net48, net7.0, and net7.0-windows.

Installation

After the package is published to Yak:

yak install hoppergroup

For manual installation, build the project and copy the appropriate HopperGroup.gha output into a Grasshopper libraries or package location.

Component Reference

The component is available under Params > Util > Hopper Group.

Inputs

• Enabled: turns the automation on or off. Default: true.
• Exit Scale: multiplier for the dragged selection footprint used as the removal buffer. Default: 1.
• Refresh: toggle to rescan all groups and repair membership for every canvas object.
• Debug: writes debug messages to Rhino command history and the Log output.

Outputs

• Status: current state and last operation count.
• Groups: number of cached group regions.
• Changes: membership changes from the last operation.
• Log: debug log.

Build

dotnet build HopperGroup.csproj

Build outputs:

• bin/Debug/net48/HopperGroup.gha
• bin/Debug/net7.0/HopperGroup.gha
• bin/Debug/net7.0-windows/HopperGroup.gha

Close Rhino before rebuilding if the plugin is loaded.

Release / Yak Packaging

Create a local Yak package with:

./scripts/release-yak.sh 0.2.0

The script updates HopperGroup.csproj and yak/manifest.yml, builds all Release targets, stages the Rhino 8 multi-target package under artifacts/yak/stage/, and writes the final .yak package to artifacts/yak/.

If this is your first Yak publish from this machine, log in first:

"/Applications/Rhino 8.app/Contents/Resources/bin/yak" login

To rehearse publishing on McNeel's daily-wiped test server:

./scripts/release-yak.sh 0.2.0-beta.1 --push-test

To publish to the public Yak server:

./scripts/release-yak.sh 0.2.0 --push-public

Close Rhino before rebuilding if the plugin is loaded. Public Yak package versions cannot be overwritten after publishing; bump the version if a pushed release is wrong. Generated release artifacts live under artifacts/yak/ and are ignored by git.

Development Notes

Membership is tested using each object's canvas-space center point. For drag removal, a single component uses its own bounding box as the exit buffer; multiple selected components use the combined selection bounding box. Group hierarchy is based on complete rectangle containment: a smaller group becomes a child of the smallest larger group whose cached bounds fully contain it.

License

HopperGroup is released under the MIT License.