> ## Documentation Index
> Fetch the complete documentation index at: https://docs.speckle.systems/llms.txt
> Use this file to discover all available pages before exploring further.
# Compare parametric design options from Grasshopper
> Mark Data Objects as design options, attach numeric properties, publish to Speckle, and explore all variants side-by-side in a dashboard with 3D views and a parallel coordinates chart.
Use this guide when a Grasshopper script produces multiple versions of the same design — different heights, configurations, densities, or any other parameter — and each version has numeric properties you want to compare. It covers marking Data Objects as design options, structuring metrics, publishing to Speckle, and reading results in a dashboard.
This guide assumes familiarity with the **Data Object** and **Send** components in Grasshopper. If
you are new to Speckle in Grasshopper, start with the [Grasshopper
connector](/connectors/grasshopper/grasshopper) and [Data
Objects](/connectors/grasshopper/grasshopper-objects) guides.
## Tag design options in Grasshopper
Use a **Data Object** component for each variant. Connect the variant's geometry to the **Geometries** input and set a descriptive **Name** (e.g. `"Option A"`, `"Variant · H2.0 · N4"`).
Each variant appears as a named object on the canvas.
Right-click the **Data Object** component and select **Mark as Design Option**.
The component displays a **Design Option** label to confirm it is enabled.
This sets the `isDesignOption` flag on the object automatically. Data Objects without this flag are ignored by the widget.
In the **Properties** input, add numeric values that describe each variant's performance or characteristics. Properties shared across **all** design option objects become the chart axes — any property present on some options but not others is excluded from the parallel coordinates chart.
Group related values under a parent key. The widget flattens nested properties using `::` as a separator and uses the last segment as the axis label.
For example, this structure:
```
cost
material: 42000
fabrication: 8500
performance
score: 87
efficiency: 0.74
geometry
height_m: 2.0
panel_count: 4
```
produces chart axes labelled **material**, **fabrication**, **score**, **efficiency**, **height\_m**, and **panel\_count**. Keep leaf names short — they appear as axis labels and in the properties panel.
The component preview shows all property keys and values alongside the Design Option label.
## Publish to Speckle
Connect the merged list to a **Send** component. Set the project and a model name that reflects the study (e.g. `facade-study`, `tower-options`).
The Send component preview shows the correct object count.
Click **Publish**. Open the model in the Speckle web viewer and confirm each variant appears as a separate selectable object with its properties visible in the properties panel.
All variants are published and ready to connect to a dashboard.
## Add the widget to a dashboard
From your Speckle workspace, open **Intelligence** and create a new dashboard, or open an existing one in edit mode.
The dashboard editor opens with the widget panel visible on the left.
In the widget panel, open the **Grasshopper** group and drag a **Design Explorer** widget onto the canvas.
An empty Design Explorer widget appears on the canvas.
Click the widget to open its sidebar. Under **Data sources**, click **Add data source** and select the project and model you published to.
The widget loads and displays a thumbnail card for each design option.
## Read the results
The widget shows three views simultaneously.
### Parallel coordinates chart
One line per option runs across all metric axes. Hover a line to highlight the matching tile in the grid. Click a line to open that option in detail view. The chart makes trade-offs visible: options that score well on one axis often score worse on another.
### Grid
The grid shows a thumbnail card for each option. Thumbnails are captured automatically from the live 3D model — no screenshots needed. Use the **Sort by** dropdown to rank cards by any metric.
### Detail view
Click any tile or chart line to open detail view for that option:
* **Properties panel** (left): all metrics as key-value pairs
* **3D viewer** (centre): the selected option's geometry in isolation, with fit-to-view and orthographic toggle
* **Filmstrip** (right): the full ranked list for switching between options without returning to the grid
Click the option name in the header bar to return to the grid.
In detail view, the divider between the 3D viewer and the options list is draggable. Drag it to
give more space to whichever panel you need.
## FAQ
The widget checks the source application of the connected model and expects Grasshopper.
Re-publish the model from Grasshopper, or connect a data source that was. If you are producing
design options from somewhere else, see [Under the hood](#under-the-hood).
Check that each Data Object has been marked as a design option via the right-click menu (**Mark
as Design Option**). Also confirm the objects are at the top level of the model, not nested
inside Collections.
Only properties that are present on **all** design option objects appear as chart axes. If a
property is missing on even one object, it is excluded. Check that every Data Object has the
same set of numeric property keys.
Thumbnails are recaptured from the live model on each load. They are not stored between
sessions. Cards are interactive immediately; thumbnails fill in progressively in the background.
## Under the hood
Nothing exotic — it writes a property. The menu item sets a boolean at the dotted path
`DesignOption.isDesignOption` on the Data Object, which lands on the wire as:
```json theme={null}
"properties": {
"DesignOption": { "isDesignOption": true },
"cost": { "material": 42000 }
}
```
The marker is excluded from the metrics, so it never appears as a chart axis.
See [`SpeckleDataObjectPassthrough.cs#L208-L213`](https://github.com/specklesystems/speckle-sharp-connectors/blob/dd065202c03a1bade2c720cce1943172389397a6/Connectors/Rhino/Speckle.Connectors.GrasshopperShared/Components/Objects/SpeckleDataObjectPassthrough.cs#L208-L213) (pinned at `dd06520`).
Not officially — but nothing about the marker is Grasshopper-specific, and the only thing
stopping you is a source-application check on the widget.
Build the Data Objects with the marker in their properties, then set the version's
source application so the widget accepts the model:
```python theme={null}
from specklepy.objects.data import DataObject
from specklepy.core.api.inputs.version_inputs import CreateVersionInput
element = DataObject(
name="Option A",
properties={
"DesignOption": {"isDesignOption": True},
"cost": {"material": 42000},
},
displayValue=[geometry],
)
version_input = CreateVersionInput(
project_id=project.id,
model_id=model_id,
object_id=object_id,
message="Design study",
)
version_input.source_application = "grasshopper"
```
Two things to watch that the Grasshopper component handles for you:
* The widget isolates the marked object itself, not its children. All geometry for a variant
must sit on that object's `displayValue`.
* Every marked object needs the same numeric property keys, or the odd ones out are dropped
from the chart.
This is unsupported and misreports how the version was produced. It works, but treat it as a
hack rather than an integration: the source-application check may be relaxed or replaced, and
this workaround will not be preserved deliberately. If you are relying on it, say so on the
[forum](https://speckle.community) — a real use case is what would justify supporting design
options outside Grasshopper properly.
## See also
* [Grasshopper connector](/connectors/grasshopper/grasshopper)
* [Data Objects in Grasshopper](/connectors/grasshopper/grasshopper-objects)
* [Intelligence Dashboards](/analytics/intelligence-dashboards)