Update Feb. 2015: A new Section is in preparation, recreating the basic shape of a "Shell House". This will be available for all student members, so join the course now before the price is increased to $69.
This is a basic introduction and overview of modelling complex 3D Freeform shapes in the context of architectural design.
Have you ever wondered how certain architectural designs are actually created? You might assume that it is helped by software, but which system is suited for this? In regular CAD software that architects often use, such as AutoCAD or SketchUp, the creation of organic models and surfaces is hard to impossible.
We use Rhinoceros, a quite popular NURBS modelling software for McNeel. This is very popular within several innovative architectural offices where it is used for complex forms, organic architecture and extensive tweaking of 3D models. The software can also be used complementary to other architectural design software, although it is quite complete in itself.
The course starts with a basic introduction and overview of the software and then a few example projects are developed. They are inspired by famous and iconic architectural projects, but are not full reconstruction. We use the examples to inspire you and focus on a certain part of element which we will strip down to the basic geometric operations, giving you insight in how to approach more complex projects.
You don’t need any other software then Rhinoceros, on Windows or OSX, but be ready to try and fail, often. As many modelling tasks require a specific order of operations. We cannot prepare a solution for every possible task, but by building upon a few basic examples, you learn an approach which focuses on dividing the task at hand into smaller problems, that are easier to tackle. And these can then be applied in other situations.
So come join us and learn the basics of 3D Freeform Modelling with Rhinoceros.
Welcome to the course in modelling complex architectural geometry, using Rhinoceros.
We start with a basic introduction to McNeel Rhinoceros, a 3D Software that is suitable for complex, freeform shapes.
We point you to the main McNeel Website (http://www.en.na.mcneel.com), from where you can find more information about the Windows version of Rhinoceros. There is an OSX Version of the software, which is not fully released yet but it can be used today and is already very promising.
There are a few active Rhino communities you can join for more information and it for detailed technical information, you may visit the McNeel Wiki pages.
Finally, we briefly show you a project inside Rhinoceros for Windows and also the Mac version.
Like most tutorials, we have to start with an overview of the Interface. Rhinoceros has a pragmatic, straight forward interface, with menus that are also reflected in the Toolbars.
The Command prompt might look familiar to long-time CAD users, as it resembles the prompt in AutoCAD. Here you can type any command, with a handy auto-complete, but also see the required input. You can even interact with the command parameters by clicking on the textual options, although you can also control it with the keyboard. Many AutoCAD short commands are also recognised.
The tools and palettes are quite flexible, but we stick with the default interface, to not confuse you too much.
The viewports show you perspective and orthogonal views on the model and can be freely organised. Double-click the viewport name to maximise a single viewport and right-click to customise it.
After you created a simple object, you can practice viewport navigation, which is essential for any modelling session: scroll to zoom (enlarge or shrink), drag with the right mouse button to orbit (pivot around the model) and shift-rightclick to pan (move) the view. The middle-mouse button displays a small context menu.
While this course is explained using the Windows version of Rhinoceros, the Mac version is (at the time of recording) sufficiently developed to be usable. Here we get an overview of the Mac interface, which does differ from the Windows version, but uses the same concepts, operations and file format.
Many operations in Rhinoceros to create geometry start from curves, so we start with 2D Curves.
We can create accurate straight and freeform lines, curves, arches and other line-based geometry.
Polylines are a series of connected straight line segments.
A control point curve is a freeform curve that is controlled by a limited number of "control points". Instead of having to painstakingly tweak a curve with thousands of small segments, you position a few control points. This is possible from a mathematical description of a freeform curve with a few basic 2D or 3D coordinates. These so-called "NURBS" are actually an extension of the Bézier splines you might be familiar with from 2D illustration software. Curves start and end with a control point and the curvature in between is steered by other control points. However, the curve does not pass through these points.
As a convenience, you can also create a control point curve that passes through clicked points, called in "Interpolated Curve", although in the back this will again be a regular control point curve.
Finally, we also make modifications to a curve, by inserting a "knot" and a new control point.
Multiple objects can be glued together using the Join command. Many objects can also be deconstructed again with the Explode command. E.g. we can explode a rectangle into four separate lines.
To create copies of elements, we can use several transformation operations, such as Move, Copy, Rotate or Mirror.
The real strength of Rhinoceros can be witnessed in the creation and manipulation of complex surfaces. The next lectures will focus on many of the operations that are provided by Rhinoceros.
We start with the creation of a few primitive objects, but also show you how you can convert an area enclosed by (planar) curves into a Surface.
An extrusion operation turns a curve into a surface, but pulling it up, in a particular direction. This is usually done vertically, but there are many variations of extrusion operations.
If you start from a closed or open curve, you can Extrude it into a vertical surface with the Extrude command from within the Surface tools. The result will still be open or closed, depending on the input.
If you apply the extrude operation from the Solid Tools, you can turn a closed curve into a solid volume in one step. This also works if you start from a planar surface.
If you explode the solid volume, you will notice that it consists of individual surfaces, as if we extruded the curve as a surface and joined it to the planar bottom and top surface.
There are always multiple ways to arrive at a certain result.
A revolve operation creates a "Surface of Revolution". Here you turn a curve around an axis line, to create a axis-symmetrical surface or volume, depending on how the curve is aligned to the axis.
We illustrate this with the creation of a simple wine-glass, starting from a control point curve.
As with most operations in Rhinoceros, they are initially one-time only, retaining no relation to the originating geometry, so if you change the curve, the revolved surface will not automatically follow. There is a method to retain this "history", but this will be explored in another course, focusing on parametric design.
With the wine glass created, we can activate the control points of the surface, to further manipulate it.
Here we need to take care of the effect of such modifications. In many cases, this will not result in a smooth continuous surface. This can be intentional or accidental, but it is one of the techniques you need to properly understand to get predictable results.
To inspect the surface quality and curvature of our model, we can use some of the visual analysis options in Rhinoceros. A temporary shader or material is applied to a selected object which assists you with the inspection of the surface.
A false-color gradient gives the curvature amount so it becomes more obvious where areas of high curvature are located.
An environment map gives the element a reflective quality, much like a car body, where distortions on the reflection point you to places with discontinuities.
A zebra map is an alternative display that clearly shows where the striped pattern is broken, to indicate the discontinuous edges.
A loft operation connects curves into a surface. This can be used to steer the section of a volume at different places in one smooth, continuous flow.
You can connect open and closed profile curves. You can steer the result in a preview dialog, which gives you more control over the operation.
Be sure to click the curves in the correct order and at a fitting position on the curve, so the surface does not flip over or intersect itself.
There are two main variations of Sweep operation. In a sweep, you get a combination of an extrusion and a loft. Here you can steer one or more profiles along a path, which gives you additional control over the shape in between the section or profile curves, which is not possible with a lof.
This can be used for ballusters, HVAC elements and all pipe-like shapes. Since you can connect multiple profiles, the sweep can make a smooth transition between these profiles.
A two-rail sweep requires two assistance paths, which are intersecting the profile at a convenient position.
Some questions about Rhinoceros and basic modelling.
In the next lectures, we will recreate a fragment of the façade of the Neue Staatsgallerie in Stuttgart (Germany), by James Stirling from 1984. While not completely fashionable today, it has an interesting curved curtain wall that consists of rectangular glass panes.
This is fairly easy to create with Rhinoceros.
We start with two simple lines. One vertical and another where we moved the lower point, to turn it into a slanted line. We work on a grid, to simplify our modelling.
The next step is drawing two more curves, to connect the bottom and top points respectively. The bottom line can be made from 4 control points and by aligning them on the grid, it becomes easier to align the orientation of the curve.
Before we make the top curve, we move our Construction Plane (CPlane) so we can draw it inside this plane.
The façade is then simple created with a Sweep 2 Rails operation.
The final step is the creation of the deformed rectangular windows.
We start from a simple rectangle, with an arbitrary size. We make multiple copies using the Rectangular Array command.
We can use the "FlowAlongSurface" command to convert and twist elements in relation to a rectangular shape onto another, curved surface. However, we need to add an actual surface underneath our rectangles first.
Be sure to click the reference (source) and the destination (target) planes roughly in the same corner, to steer how they will be aligned.
The Nestlé Laboratory project is a nice example of fairly basic Boolean Operations, but with a surprising result.
In Boolean Operations, which are widely used in Architectural Modelling, you perform operations with 3D volumes, like subtraction, union and difference. They are easy to comprehend and allow the creation of some particular shapes that would be impossible to create otherwise. However, mathematically, they are quite intensive and complex, to cater for all possible exceptions and the limitations of numerical approximation in computing algorithms.
The stark contrast between the straight and cold metal cladding and the warm, orange curved inner surfaces can be recreated by subtracting spherical volumes from the main boxes.
To assist us, we will use a picture as an underlay when modelling.
You can download the reference picture from the ArchDaily website and set this up as a "Background Image" in Rhinoceros. We have to ensure that it is scaled to an approximation of the exact sizes.
With the bitmap placed in the top viewport, we can draw polylines over the corners of the three main building blocks.
They can be extruded to form the main building block volumes.
To recreate the spherical voids, we start from circles. Using the "Circle from 3 Points" variation of the Circle Operation, we can point to three points on our background to get a reasonable approximation of the outlines.
To create the Spheres, we can set our Object Snap (OSnap) option to Cen(ter) and Quad(rant), so you can easily click on a circle to find the center of the sphere and click again on one of the 4 quadrant points to finish with the exact same radius.
P.S. We know that the actual spheres in the project are not all laying with their center on the ground plane, but this is more an approximation to illustrate a modelling technique rather than a full recreation of the model.
Before we do start our final operation, we make a small correction to the height of the building, with one of the Solid Editing operations to move a face. We use the "normal" option, to move it vertically.
Next we can use the Solid Boolean Difference operation to subtract the volume of the spheres from the main building block.
While this is a fairly complex operation, it is fast with this basic model. The original sphere are removed, as we don't need them anymore.
The Kunsthauz in Graz (Austria) is not only famous for its organic, blob-like shape, but also for its media façade. We will focus on the skylight shapes, which extend from the roof, in a smooth transition.
To keep the exercise simple, we will approximate the skylights as a rounded cylinder that punches out of the basic roof shape. We'll use an ellipsoid, but the technique works for any form.
As always, this is just a fragment and meant to teach you a technique that is applicable in another context. And please understand that there are often multiple ways to reach the same result.
We start with a solid ellipsoid shape, which can be found in the Surface Tools. We use a grid and work centered around the origin of the scene, which makes modelling and transformations easier.
Add a cylinder and move and rotate it so it overlaps the ellipsoid.
Now we are ready for the next step.
We use the Trim operation in two ways to make the cuts between the cylinder and the ellipsoid.
When using the Cylinder as the trimming object, we can cut out a circular hole from the ellipsoid. Confirm this by temporarily moving the cylinder out of the way.
The second operation is also a trim, but used in a different way. We draw a line which will act as a cutting plane, to trim the lower part of the cylinder.
In this step, we want to prepare the smooth transition between the cylinder and the trimmed ellipsoid.
We use the circular cut edge on the ellipsoid and make an offset copy, onto the surface, using the "OffsetCrvOnSrf" operation. This ensures that the new offset copy lies exactly on the surface of the ellipsoid.
Then we are ready to trim away the part between the original cutting edge and the new offset copy, so the hole in the ellipsoid is increased in size. This gives us more space to make the transition.
Finally, we use a quite complex operation, which is presented by Rhinoceros in a fairly simple dialog.
A Surface Blend requires two open edges on different surfaces and they are connected by a smooth surface. Within the dialog you can choose between different types of continuity.
Within the Surface Blend dialog you can also adjust the size of the continuity, which sets the distance between the aligned control points. Or you can do this by dragging the handles in the viewport.
This is in fact a very powerful and complex operation which is made accessible even for new Rhinoceros users.
We finish off with a Fillet to give the top of the cylinder a rounded edge.
The Metropol Parasol is a remarkable and organic new design, overarching a public square in Sevilla (Spain) by J. Mayer H. Architects (2011). We focus on two aspects of this design:
We don't create the actual volume, but follow a procedure that gets an overall shape, started from simple volumes. It teaches us an alternative approach for a smooth blend between the basis and the top shape.
We start from an ellipsoid shape.
The foot of the mushroom is created from four control point curves, positioned around the origin. It is best to draw them from the Front and Right viewports. Connect them with a Closed Loft surface.
To close the volume, we use the Cap Planar Holes operation, which puts a flat bottom surface underneath the foot and joins it with the loft.
Then we try to join the two volumes with a Boolean Union, but since the foot is not fully closed, the operation fails. No problem, though, as there are still other techniques available. We use the Trim operation to cut the bottom from the top and the top from the bottom and now we can union them properly.
Finally, we use a fillet edge operation, to make the transition between the bottom and top part smooth.
We copy our mushroom and use a non-uniform scaling (1D) to stretch it up a bit.
With two lines in the Top view we can trim a part of the sides to make room for a Surface Blend.
In this case, we are not able to reach G2 continuity so we fall back on Tangential (G1) and try to avoid a self-intersecting transition shape.
We can finish by joining all shapes so we have one continuous volume.
The last step takes a bit more work, but illustrates a method that can be used to prepare your model for digital fabrication with flat panels, e.g. for a scale model on a Laser Cutter.
Using a Grid Snap, we draw Section Lines to cut through the volume. We create them on two different layers, for easier display afterwards. We keep the section lines grouped per section plane.
When we have a series of sections, we can extrude them, so they become solid volumes. However, due to some geometry irregularities, some sections fail.
We can solve this, by removing the leftover extrusions and deleting some of the control points to arrive at a section without any self-intersections. Then we can properly extrude them.
Some basic questions to review your understanding of Rhinoceros modelling.
Thank you for taking this course. I really hope you enjoyed it and please stay in touch. Leave a message on the Discussion Board, leave an honest review or spread the word to other possible students. This really helps me continuing making new courses and improving the existing ones.
And if you have a question, do not hesitate to ask.
Stefan Boeykens is an architect-engineer from Belgium.
After graduation, he worked a few years as a professional architect, for several local offices, where he was involved in design, building permits, drafting, site supervision, visualisation and IT management.
At the end of 2000, he got the opportunity to return to his former university (KU Leuven), at the Department of Architecture, where he started teaching Computer Aided Architectural Design. Initially AutoCAD and 3D Studio VIZ, but step-by-step, he introduced SketchUp, Rhinoceros + Grasshopper, ArchiCAD, Artlantis, Unity, Processing and Cinema 4D. He completed a PhD on Building Information Modelling in 2007 and worked a few years as a post-doc, focusing on the use of BIM throughout the design process. He became familiar with a wide variety of IT skills: Windows, OSX, Linux, VBA in Excel, php, C++, Java/Processing, Autolisp and C# in Unity.
At the moment, Stefan is a part-time guest professor at KU Leuven, teaching primarily ArchiCAD, Grasshopper, Cinema 4D and Unity, where he has created several online video tutorials.
In parallel, he is working as a BIM specialist/consultant for D-Studio, a Belgian company focusing on BIM middleware and consultancy.
He is father of three boys and enjoys reading, cycling, loosing time online and learning.
If he has some additional time, he likes to compose music, mainly focusing on guitar, but occasionally with vocals, synths and laptop drums.