Column Grasshopper Styles Tutorial

Comparison between the Grasshopper column on the left and the VisualARQ column on the right.

In this tutorial a parametric column style from a Grasshopper definition will be created.

The 3 main steps to follow are the same as in any other Grasshopper style:

  1. Grasshopper definition setup
  2. Create the VisualARQ column style
  3. Insert and edit a VisualARQ column created from a Grasshopper style

1. Grasshopper definition setup

You can download the complete Grasshopper file clicking here.

Type Grasshopper in the Rhino Command line to launch Grasshopper.

The GH definition requires some Input parameters to define the feature of the new object, and Geometry Params as Output components:

  1. Input parameters components: define the features of the resulting column style. In this definition there are parameters of these types:
    • Numeric value (floating point): three sliders that define various dimensions of the column and one that defines the rotation.
    • Numeric value (integer): one slider that defines the amount of pairs of elements.
  2. Output components: they are “ending” Geometry Params, that are no further connected to any other component. They will be read by VisualARQ as the different parts of the column. In this example there is one Brep Param for the whole column geometry. Breaking this definition down into different parts (“ending” Geometry Params) will let you later on edit the attributes for each one of these resulting parts individually.

The complete Grasshopper definition is shown in the image below:

The column Grasshopper style definition. On the left the various input parameters and on the right a brep component as output.

The Grasshopper definition that generates the column.


2. Create the VisualARQ column style

In this case the Grasshopper style will be created and managed from the Column Styles dialog.

2.1: Create the new style

Assuming the Grasshopper definition (.gh file) is already done, open the column styles dialog: _vaColumnStyles.

Click on the New… button and select the Grasshopper style option.

The column styles dialog with the "Grasshopper style" option visible after clicking on the "New..." button.

The Grasshopper Style wizard will appear. This wizard will guide you through the steps to define the column Grasshopper style parameters. The left side of the wizard will show a preview of the object style generated as soon as the required information is completed.

2.2: Open the Grasshopper definition

Click on the Browse button to select the .gh file created before.

First step of the Column Grasshopper Style Wizard. In this step the Grasshopper file is selected.

2.3: Configuration

Set the Column Grasshopper style global values:

  • Style name: Set the desired name.
  • Definition units: In this case the Grasshopper definition was created in millimeters.
  • Insert point: The base point to place the column, any input Point parameter in the GH definition will be available here. If no point is chosen the origin of the GH definition will be used instead. In this case the column was build according to the origin of coordinates, that’s why no point is needed.
Second step of the Column Grasshopper Style Wizard. In this step the name, the units and the optional Insert Point from the Grasshopper file are selected.

2.4: Geometry

Specify which of the geometry components (Params) to import into VisualARQ. The identifiers of these Geometry components are taken from the names of the output components in the Grasshopper definition and can be modified only once the style has been created.

Each component can be assigned to a different representation:

  • Model: the object representation in 3D.
  • Plan: the object representation in plan view. Only visible when the Cut Plane of the level where the object is placed is enabled and intersects the element.

In this case there is one Brep output that corresponds to the Model representation. The Plan representation will be taken from the real horizontal section of the 3D elements according to the level’s cut plane height.

Third step of the Column Grasshopper Style Wizard. In this step the geometry to be displayed and its representation is chosen.

2.5: Parameters

This step shows the settings available for the list of input parameters that define the column style. The “Filter by” dropdown can be used to view individually each one of the named groups of input parameters that were created in the Grasshopper file. The settings available for each of the inputs are:

Name: is the identifier of the parameter and can be modified if desired in this step.

Editable by:

  • Definition: the parameter will be hidden in the VisualARQ style and properties dialog.
  • Style: the parameter can be edited by style, so the changes will apply to all elements with that style.
  • Object: the parameters can be edited individually for each instance of that style in the model. In case no value is provided “By object” the one defined by style will be used.

You can change the “Editable by” setting for multiple parameters by selecting them while holding the Ctrl key.

Fourth step of the Column Grasshopper Style Wizard. In this step one of the settings is the "Type", which allow to set the corresponding value type for each of the parameters.

Default (value): shows the default value for the parameters (the ones specified in the Grasshopper definition) and lets you set different default values.

Type: shows the different types of values available for each kind of parameter. In this case most of them are floating point values of type Length and one Integer (defined in the gh file). The only one that should be changed manually is the one corresponding to the rotation, which should be of type Angle.


3. Insert and edit a VisualARQ column created from the Grasshopper Column Style

3.1 Edit the column style

Once the Grasshopper style wizard is completed, the new style will appear in the column styles list with its corresponding subcomponent. To edit the style again, right-click on the style name to open the context menu and select Edit. This operation will open the Grasshopper style wizard again. The parameters are available under the “Parameters” tab and appear grouped as in the Grasshopper definition. In case the name of the group matches an existing category they will appear combined.

The Column styles dialog with the new column style. When it is selected the parameters appear under the "Parameters" section grouped as in the Grasshopper definition.

3.2 Insert the Grasshopper style

Once the column style has been created, you will be able to insert an instance in the document. You will be able to change the values of its parameters from the VisualARQ column icon located under the Properties panel. Only those input parameters that were set as editable “by Object” in the step 2.5 will be visible.

Example of a column with the new style. Some of the input parameters appear in the Properties panel since they have been set as editable by object.