Lecture 4, 5/27/2017, Rhino Interface an overview

Transcription

1 數字建築與城市设计 Spring 2017 Lecture 4, 5/27/2017, Rhino Interface an overview Copyright 2017, Chiu-Shui Chan. All Rights Reserved. This lecture concentrates on the use of tools, 3D solid modeling and editing Rhino is designed as a Nurbs Modeler. Nurbs stand for Non-Uniform Rational B-Splines. This basically means that smooth surfaces can be created through mathematical formulas. What this means to us is that complex smooth forms can be created that are highly adjustable and editable for designers. In traditional computer modelers, surfaces are defined by a series of flat planes joined together to create a facetted surface. Nurbs modelers allow us to create smooth complex surfaces by simply defining a couple of points that can then be manipulated. However, when it comes to simple modeling, Rhino is a very easy to use and a highly intuitive modeler. In fact, who uses Rhino? Industrial designers, architects, vehicle designers, jewelry designers, and sculptors use Rhino. Yet, people in film and TV effects, game design, and character design would use 3D Studio MAX, Maya, or MODO instead or using Rhino. Here is the re-start of the introduction of Rhino in 3D as a fresh beginning for your modeling purposes. Hopefully, after this lecture, you will be competent to start working on your Rhino modeling. Rhino 3D Basic Modeling Tools: Command Prompt View Controls Rendering Controls Assist/Properties Pallet The Modeling Windows The Modeling Tool Pallet Snap Etc. Controls Rhino has a typical Modeling interface. By default it is composed of four view points and a tool palette on the left. At the bottom are the ortho and object snap controls. At the top are the Pan and Zoom Controls, as well as the tool command prompt. Page 1 (5/15/2017)

2 Setting up grids and units for accurate modeling: Click on File>Properties to open the settings window, which is the same as Tools > Options Click on the units Tab > Model and select either Millimeter or Inches. Match your unit with the Distance Display. Units Tab Units Setting Grid Tab Major Grid Lines Match your units Snap Spacing Click on the Grid Tab and set a grid snap and grid spacing. Note: if you are using Feet and inches, a grid unit of 12 (or 8) is best; and 10 is best for metric. Display Setting Snap, Ortho, Planar, OSnap, Record History, and S-Track: The bottom of the Rhino interface is a number of drawing aids. These allow you to lock lines and Snap as needed. Project: Will project line snapped to geometry onto the ground plane, useful for creating Plan outlines. Diable: Disable the O-Snap functions. Page 2 (5/15/2017) Record History: Allows you to link lines to surfaces. If you change the line, it will update the suface (kind of works). S-Track: Allows you to snap projection line from multiple types of geometry. Osnap: (Object Snap) Activates the snap menu. Will snap lines to geometry as you draw. Planar: Keeps curves in a set plane as you draw from on view to another. Ortho: Locks lines to 90 Deg. Hit F8 to toggle or hold down shift key while you draw. Snap: Toggles the grid snap on or off that we just set.

3 The Tool Palette: Selection Tool: Used to select and move objects Draws Points: Used to place single points. This can be used with rail sweeps. Draws Lines and Curves: Used to construct splines for surface and object generation. See below. Draws Circles and Ellipses: Used to construct closed curves. Draws arc s. Draws Rectangles. Draws Polygons. Fillet Tools: See Below. Hold down mouse for more options. Surface Tools: See Below. Hold down mouse for more options. Advanced Surface Tools: See Below. Hold down mouse for more options. Solid Tools: See Below. Hold down mouse for more options. Boolean Tools: See Below. Hold down mouse for more options. Curve from Object Tools: See Below. Hold down mouse for more options. Mesh Tools: See below. Hold down mouse for more options. Join Tool: Used to join together two surfaces. Explode Tool: Used to break apart joined surfaces. Trim Tool: Used to cut a surface with another object. Slit Tool: Used to cut a surface with a cutting object. Group and ungroup tools. Control points on and off toggle tools. Point editing controls: see below. Hold mouse down for more options. Place text tool. Transform tools: Hold mouse down for more options. Copy Rotate and Scale Tools. Analysis Surfaces Tools. Most of the items in the tools palette can also be accessed in the menus palette. In the Menus palettes there are also more specific tools associated with its menu item not listed in the tools palette. Curve (Curve) Tools are used to create curves. Curve (Curves) Tools are used to adjust and fix existing curves. These include Fillets, Chamfers, Offsets, Fix Points, Simplify and Rebuilding Curves. Page 3 (5/15/2017)

4 Surface creation Tools: This palette is used to generate surfaces from Points and Curves, Lofts, Surface from Curve Network, Sweep along one and two rails, Revolve, Patch, and Drape Functions. Surface editing tools: These are used to edit, adjust, fix and rebuild surfaces. Solid Creation Tools Pallet: This is a typical pallet of object primitives that can be created. Solid Editing Tools: These includes difference, union, intersection. As well as fillet, cap holes, and extract surfaces. Curve From Object Palette: This is used to generate curves from objects that then can be used to generate more surfaces. You can also generate a series of contours from an object, section curves, etc. Mesh Tool Palette: This is used to extract mesh surfaces and objects from NURBs surfaces. This is useful for exporting into other programs. You can also create direct mesh objects without creating a NURBs object first. Page 4 (5/15/2017)

5 When we work on modeling, we first would redefine the selection color before we start: 數字建築與城市设计 Spring 2017 Tools > Options > Appearance > Colors > Change the Background color to white, Feedback, Tracking lines, Crosshair to red, and Selected Objects to red for legibility. In the following examples of creating curves and curved surfaces, we also would set up the value of Tools > Options > Units > Absolute Tolerance up to for providing more accurate detail to display the computed or calculated curvature of curved surfaces. The absolute tolerance value will maintain the geometric results of surfaces. Whatever the changes it made, the resulting geometry will not be modified. In other words, a changed tolerance only affects objects created from that point forward; and it doesn t change old objects at all. In that case, you might have some problems on having different tolerances on different geometry. When combining these geometries together, serious modeling problems will occur. So, please be aware of that. After the units, grid line count of 400 along each side of the axis of the view port, the absolute tolerance of 0.001, and the color representations were all well-defined, these settings will serve for our own functional requirements. Thus, we did actually customize an ideal modeling environment to serve our own convention, which will be constantly used in the future modeling tasks. Such a customized environment could also be saved in Rhino data base. File > Save As Template > In this example, I would save it as CSC Large Object Inches as a part of the defined template. Whenever it is opened, the same setting will be applied for my best convenience. Solid Modeling Method 1: Extrude 2D to 3D to make a curved façade or solid In this method, 2D drawings should be done first. Line drawings are covered in last lecture. For drawing curves, Handle Curve, Control Point Curve, Sketch and Curve: Interpolate Points, are popular tools used to drawing curves. Among them, Interpolate Points is the best drawing tool to use (my favorite one). These curves could be modified by moving the control points (select curves first, click F10 to turn it on and F11 function key to turn it off). Select the curve > Surface Creation > Extrude Curve Straight (or Surface menu > Extrude Curve > Straight, or type Extrudecrv), then the curves will be extruded to meshes. If turn the Solid option (inside the functional selections) on, then a solid mesh will be created to make the entire mess. This method extrudes open or closed lines to surfaces (or solids). By turning the control points on, there are handle and angle handle that could be used to change the size and rotation angle. The extruded surfaces could be edited by cut and trim functions. Solid Modeling Methods 2: Creating solid objects by solid creation tools of sphere, cone, box etc This is a simple concept of using primitives as basis for modeling. In Rhino, a solid is an object that has no naked edges, and its outer surfaces are completely joined. On the other hand, solid is an accurate mathematical description of a volume. Thus, solids in Rhino are multiple NURBS surfaces joined into one primitive. Primitives are basic geometric shapes like a cube, sphere, cylinder and pyramid. All operations concerning creating and editing solids could be bound in the menu Solid. 1. Solid menu > Cone, pyramid, box, sphere to construct 3D solid forms, or 2. Use cone, pyramid, box and sphere tools inside the Solid Tools to create 3D objects as well, or 3. Use Solid Creation Tool to generate forms. Solid Modeling Methods 3: Creating surfaces with lofts, revolve, Sweep 1 Rail and Sweep 2 Rail Options. More of this group will be covered later in Lecture 5. Today s lecture is to provide sequential information on the methods of generating 3D sold objects. Page 5 (5/15/2017)

6 Solid Modeling Method 4: Creating Objects Using Boolean Commands: To create an object in Rhino, click on one of the Solids from the Solid Creation tool pallet. This box is defined by two points and a height. Height Two base points Note: use multiple windows to create your box. Define the base point in either the top or the perspective view, then activate ortho at the bottom of the modeling window, and then extrude the box in either front or side view. Or simply click two points to define the base and move the mouse up to define the height. Creating complex objects in Rhino is easy to do using the Boolean operations. Simply build the object you want to cut and place it in the correct location relative to the object you want to keep. Object to cut (Shown highlighted) Object to keep Deselect all objects, and click on Solid, then Difference. Note: in this same menu you have Union and Intersection as well. Select the Difference from solid, or the menu item of Solid, then Difference. Click on the object you want to keep, first. Hit return, or right click. Then click on the object or objects to want to cut from with. Hit return or right click again. If the DeleteInput option is changed to yes, then the cylinder will be erased at the final form. Page 6 (5/15/2017) Cut object

7 數字建築與城市设计 Spring 2017 Second example of mechanical components: Method 5: Adjusting Surface/model by Editing Ctl Points Along with normal objects, you can adjust blobs. Start with a sphere. Click on the solids menu > Sphere > Center, Radius. Click in the screen and draw a sphere. You can now move the control points that define the sphere by clicking on the Edit points on tool. With the sphere selected, click on this tool Page 7 (5/15/2017)

8 to turn on point editing (or select the sphere, then hit F10 or F11 function keys). Now in plan or front view select a series of points. Then click and drag the points stretching out the sphere. Note: This will not work with rectangular solids, but will work with spheres and surface. Control points on, and select one point or a row of points. Selected points moved and sphere is deformed. Or use window selection to select the entire row and column, and move. This method will make the entire side shape smooth. This process can be applied to almost any NURBs surface. Rendered Sphere. In this 5 th example, Control Points were used to control the geometry of shapes. More control points in a shape would give better control of their form changes to generate smoother results. In Rhino, control points were organized as 3 by 3 matrix and more points could be added to a curve or surface by InsertControlPoint function. Likewise, this sphere example could add extra control points, which will turn the object into a polysurface. For most of polysurfaces, control points will not be able to be seen and used for the geometric modifications. For instance, results of Boolean objects are polysurfaces which can t see the control points. Or after adding control points to the surfaces, these points disappear as well. Thus, their control points cannot be accessed by F10 key, but only can be seen by the following function: Solid > Solid Edit Tool > Turn on Points (or Solid Tools > Turn on Solid Control Points) tool to make the points visible and selectable. From moving the points along x or y axes, the geometries will be modified. See images on next page. The sphere is still a primitive object which has 3x3 matrix of control points, whereas the Boolean objects on the left has just control points occurred at the juncture of different surfaces. Those are the shared edges, and seams which could be selected, moved, rotated, or 2D scaled. Page 8 (5/15/2017)

9 On the other hand, more control points will make the model more complex, which is not a good idea. It is because that a good model should always be simpler. That means creating a surface from the fewest number of curves, and control points. When dealing with NRUBS and curves, simpler is always better. Therefore, you have to find a balance between the complexity and the number of control points. Method six: Transform solids by Gumball Widget Gumball displays the gumball widget on a selected object facilitating move, scale, and rotate transformation around the gumball origin. We could also select a group of object and click gumball to work on the transformation of the selected group of objects. See the following images. Three mechanisms available, these are move arrows, rotation arcs, and scale handles along x, y and z axis. On the side, there is an axes plane indicator that signifies the active plane. The properties of the gumball could be modified or customized through right click on the gumball box > Settings. Details of the use of gumball could be found in the Vimeo video: Footnote: The first (2D to 3D), second (3D primitives), and fourth (Boolean) methods relate to the construction of solid forms that have clear shapes and plan of composition. The third (Loft) and fifth (Control points) methods relate to the creation of organic forms that do not have clear (or precise) final form, or the final form might not be that easy to mentally visualize. In fact, the fifth method is used more on editing the form and the sixth one is for transformation purposes. This lecture provides enough concepts on the categories of 3D solids generation and editing. Next lecture, we will concentrate on architecture modeling. Page 9 (5/15/2017)