Click here to play a movie (6.2Mb) in which we look at a variety of 3D models in both the AutoCAD and IntelliCAD environments. Please note that you do not have to do anything while the movie plays, just watch!

Click here to play a movie (5.5Mb) which shows you how we used the 3D capabilities of IntelliCAD to create a model for a garden design where we wanted to give our client some appreciation of how the finished garden would look when constructed.

     Module

    Description

Extruding Entities

Creating 3D models by taking a 2D plan design file and extruding entities in it. We show how the CHPROP and CHANGE commands can be used to edit an entity's thickness value, producing an extrusion in the Z axis. By way of example, we build a model for a simple courtyard. The ELEVATION command is introduced - a command which allows placing entities at different levels in your design. The practical use of these three commands is shown in the context of "building" the walls of a 3D house. We then introduce and explain the importance of controlling layers when building 3D models. This makes subsequent rendering of surfaces in the model (from a materials library) much easier. We develop a default drawing suitable for the creation of 3D models. As an extension, we build a 3d model of a simple warehouse.

The 3DFACE command

3DFACEs being like an extruded line, can be oriented in any direction and not just vertically. Various methods of defining a 3DFACE - typing a coordinate, drawing 2D and then moving the 3DFACE, stretching a 3DFACE, using 3D point filters, .XY filters, draw in 2D and then rotate into position, use OSNAP and adjacent geometry. We briefly introduce the use of construction geometry to help define reference points in 3D space. We use the 3DFACE entity to create the roof panels of the simple 3D house. We highlight how useful the 3DFACE command is, but how difficult it is to define the corner points in 3D space when using the command.

3DMESH entities

The 3DMESH command can be used to construct complex surfaces. A 3D Mesh entity is a series of connected 3D faces. The surfacing commands REVSURF, TABSURF, RULESURF and EDGESURF, are used in conjunction with the 3DMESH command to automatically create 3D meshes in simple ways. The effect of the SURFTAB1 and SURFTAB2 variables, and tips on how they can control the density of the meshes produced is demonstrated.

The VPORTS & DVIEW commands

Previous modules concentrated on techniques for building 3D models. The value of a block library containing 3D objects - 3DPlant symbols, furniture, light poles, benches, table tennis tables etc. is illustrated. In this module, we illustrate how important it is to understand and be able to control your view of the model with VPORTS, VPOINT and the DVIEW command. We show how perspective views of 3D models are possible using options within the DVIEW command.

Creating  Intelligent 3D entities

Building some 3D objects with appropriate layers and attributes such that subsequent rendering is made convenient. The importance of layers for assigning materials to surfaces.

The UCS and its operation

We introduce the UCS and its operation and recommend that the manipulation of the UCS provides an easy way to help with drawing in 3D. The previous problems shown with defining the corners of a 3DFACE entity will be used as an illustration as the UCS can be initially a little confusing to understand.

WE will also re-inforce  the value and operation of the VPOINT command at this stage. The VPOINT command sets the viewing location while the UCS defines the current drawing plane. We show that the best way to use VPOINT is to use the "R" (rotate) option. This involves setting the viewing direction, followed by the viewing elevation angle. This a very easy way to use, and understand, the VPOINT command.

To begin with, we show that the best starting point to show the UCS operation is to set a 3D VPOINT (say, VPOINT R 30 30) and then the demonstrate several of the UCS options.

The 3D view will show the UCS icon changing position. WE make sure that the UCS icon is ON and discuss the UCS variable UCSICON and its options at this stage. The most useful UCS functions are illustrated - UCS X 90 (to rotate 90 degrees about the X axis) and UCS Y 90 (to rotate 90 degrees about the Y axis). We show how these two commands can be used to switch the drawing planes between the X, Y and Z axes. The UCS W option which will return you to the WORLD UCS is covered as is PLAN will revert to looking straight down on the current UCS. By the end of the module, students should know enough about the UCS to enable practical 3D drawing.

Third Party rendering

We discuss how a third-party rendering program may be required to render good 3D images, and show how to export the AutoCAD 3D geometry in the best possible way. Comments here address how the values for the SURFTAB variables, when creating meshes, will have a key influence on how good the 3D geometry may appear in a third-party rendering program.

Solid modelling

All we've covered so far relates to "surface" modelling. If appropriate, the specific operation of "solid" modelling may be introduced. If the students were mechanical designers then solid modelling would be very helpful to them. If the students were Architects then solid modelling would be less helpful. Solid modelling duplicates the way machine parts are made. You add or subtract material from a base solid object. This results in some 3D operations being far easier than surface modelling, while other operations are much more complex. One issue which will determine whether you can address solid modelling will be the version of AutoCAD/IntelliCAD you're using. The standard version of IntelliCAD doesn't offer solids.

Preliminaries

Setting up your CAD program for 3D CAD work. More on wire frame modelling vs. solid modelling.

Some 3D Blocks

Bringing it all together. Given a site plan, part of a house located on the site and back yard with some existing trees, your task is to populate the design with trees and other furniture taken from  the block library. Setting up a site plan for design work. Using the VPORTS command to save several configurations for ease of working in 3D. Setting a suitable GRID and SNAP value, rotating the design grid. Placing edging and paving on the plan. Examining a composite view of plant symbols and using them in a garden design. Scaling 3D blocks for added interest.

Sample Project 1

We build a design for an outdoor area in a garden.