To create the definition from scratch, we’ll first need a set of curves in which to Loft the tower surface. In Rhino, Open the file Panel Tool_base.3dm also found in the Source Files folder. You should find 4 ellipses, which we will use to help us define our surface, and some preset pattern geometry in the scene. Let’s start the definition by creating a lofted surface: • Params/Geometry/Curve – Drag and drop a Curve component onto the canvas • Right-click the curve component and select “Set Multiple Curves” • When prompted, select the 4 ellipses in the scene, one by one, starting from the bottom most curve and working your way up to the top • Hit enter after you have selected the last ellipse As we have done in some of our previous examples, we have now implicitly defined some Rhino geometry within Grasshopper. • Surface/Freeform/Loft – Drag and drop a Loft component onto the canvas • Connect the Curve output to the Loft-S input If you right-click on the Loft-O input, you will find the typical loft options associated with the Rhino command. In our case, the default settings will suffice, but there might be a time when these setting would need to be adjusted to fit your particular need. ∗ Optional Step: It is almost impossible to tell whether or not your lofted surface is facing the right direction. However, through trial and error in setting up this tutorial, I noticed that my default lofted surface happened to face inward, thus causing all of my panels to face inward as well. So, we can use the Flip component to reverse the normals of our surface to face outward. We will put the component in our definition, but if you find that when we get to the end of the definition that all of your panels are facing the opposite direction than what you intended, all you will need to do is delete the Flip component and reconnect the appropriate wires. • Surface/Utility/Flip – Drag and drop a Flip component onto the canvas • Connect the Loft-L output to the Flip-S input • Params/Geometry/Surface – Drag and drop a Surface component onto the canvas • Connect the Flip-S output to the Surface component’s input • Right-click on the Surface component and select the check box next to the word Reparameterize Currently, our surface has a domain interval that ranges from zero (at the base of the surface) to some number representing the top of the surface. We really don’t know care what that upper limit is, because we can reparameterize the surface. Meaning, we will reset the domain of the surface to be an interval from zero to one, where zero represents the base of the surface and one represents the upper limit of the surface. This is a crucial step, because our
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For plugin version 0.6.0006