3-D Modelling with AutoCAD/IntelliCAD
Most drafters who have used AutoCAD or IntelliCAD software for some time and who have been creating designs (plans) in two dimensions (2-D), find moving to three dimensional modelling, quite an intimidating step. There are two inherent problems in making the transition:
- Firstly, there is the challenge of properly orienting oneself in a three dimensional design space while working on a 2-D screen.
- Secondly, the complexity of the line work created when you are working in 3-D, can create images which are very difficult to interpret.
It's not that hard!
Sample some materials from the course
Our courses feature many small instructional movies. These show you how to carry out a task and invite you to follow suit. 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.
To hear the sound which accompanies the movie, make sure that you have your speakers connected and turned on. The movie can be paused and re-started by hitting the space bar.
Some assumptions
We assume that you have become familiar with designing in 2D using your CAD software (IntelliCAD or AutoCAD) and want to use the very same software in the 3D environment.
We will provide some review of your 2-D skills if you send some sample drawings to us.
Prerequisites
You will need a full copy of IntelliCAD or AutoCAD to take this course. While AutoCAD LT can be used to view 3D models created by the two applications mentioned, does not allow access to a full range of 3D commands. For example, the 3DFACE command has been inactivated in AutoCAD LT. An understanding of basic 2-D drafting using AutoCAD or IntelliCAD where you have been working wholly within tiled model space. We would normally expect that you would have completed QuickStart CAD, Basic CAD 1, Basic CAD 2, and Paper Space & Model Space courses, prior to taking this course. It is a good idea to download a (free) version of SketchUp from Google so you can practice passing your models from IntelliCAD or AutoCAD into SketchUp.
The syllabus:
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. |
Some background
Here we offer some background to those contemplating taking the course. It is taken from the first module in the course.
Problem #1: spatial orientation
|
|
| Your CAD software has some in-built tools to assist in orienting you in space. It is possible to select one of set of fixed preset viewpoints which orient you in 3D space. The cyan colour on the seat of the chair is an indicator that you are looking above the model in the non axis views. |
Problem # 2: Masses of overlapping lines
|
|
| An example of the crowded line work seen when you work in 3D. Your software already has tools to help resolve this problem. The HIDE command can be used to remove lines hidden by those in front as shown in the figure below. |
|
|
|
The same view after applying the HIDE command. |
What is 3-D modelling?
Put simply, when working in the third dimension, elements are placed into a three dimensional space by giving them not pairs of Cartesian coordinates as you are used to doing in 2-D work, but supplying a third (Z) coordinate whenever you are asked for a 'From:' or 'To:' point as you place the entity.
It is not as difficult as it sounds. In many cases, we still draw in 2-D, but either give the entities (lines, arcs or polyines etc.) a thickness (extruding in the Z direction) or simply move the entities to a new elevation (height off the ground).
You do not need to start up a special default drawing to do this, IntelliCAD is always working in a 3-D design area; it's just that in 2-D drafting, you normally ignore the third Cartesian point and IntelliCAD/AutoCAD assumes automatically that the third coordinate is zero.
|
|
| Listing the line which runs to the top of the frame out to the right, shows a Z value (or height above the ground - elevation) of zero. |
Types of models created by IntelliCAD and AutoCAD
IntelliCAD and AutoCAD support a number of profoundly different types of three-dimensional models - wire frame models, surface models and solid models.
We will not cover solid modelling (where essentially the software works with blocks of solid material such as steel or wood) in this course, but will we show you how to construct both wire frame and surface models.
Wire-frame models, consist of lines and curves that define the edges of a three-dimensional entity. You can create a wire-frame model by drawing lines, arcs, polylines, and other two-dimensional entities anywhere in three-dimensional space. Wire-frame models have no surfaces; they always appear as outlines. Because you must individually draw and position each entity that makes up a wire-frame model, creating them can be exacting and time-consuming.
Surface models, which consist of both edges and the surfaces between those edges. You create surface models by applying elevation and thickness to two-dimensional planar entities or by using specific three-dimensional entity-creation commands. Surface models consist of individual planes forming a faceted, polygonal mesh.
A wire-frame model
|
|
| A rectangle 500x400 mm, a circle, an arc, a polyline and a polygon; each given a thickness (extruded in the Z direction) |
Now we will look at these very same entities from one of the preset non axis views.
|
|
| The same entities viewed from an non axis view above and to the right. |
Surface models
IntelliCAD and IntelliCAD support the creation of lots of surface models. There is even a toolbar to place them - cones, cubes, tubes, etc.
|
|
|
Several 3D surface mesh shapes have been placed into this drawing. |
REVSURF
The RULESURF command is of interest as it can be used to create some surface mesh models of great complexity in a very short space of time indeed.
|
|
| An urn created using REVSURF. Note the use of three VPORTS to better visualize the model. |
Visualization techniques
As you create three-dimensional entities, the program displays both wire-frame and surface models in wire-frame view, which makes it difficult to visualize your three-dimensional models.
To better visualize the model, the software allows the use of a command (HIDE) which allows you to remove all the lines that are hidden behind other entities or surfaces when seen from the current viewpoint.
|
|
|
Surface mesh wire-frame on the left and the same model with the HIDE command applied on the right. |
Shading
Shading goes a step further by removing hidden lines and then assigning flat colours to the visible surfaces, making them appear solid. Shaded images are useful when you want to quickly visualize your model as a solid object, though they lack depth and definition.
|
|
| The SHADE command applied to portion of the ControlRoom drawing |
Rendering
Rendering provides an even more realistic image of your model, complete with light sources, shadows, surface material properties, and reflections, giving your model a photo-realistic look. When you render a model, the program removes hidden lines and then shades the surface as though it were illuminated from an imaginary light source.
|
|
|
|
A wire frame image of the International Space Station on the left and a rendered image on the right. Textures have been applied to the surfaces of the model to create the photo-realistic effect. |
|
Rendering and shadows in other software
|
|
| A fully rendered design in Google SketchUp. Note the shadows being cast. We can even set the latitude of the site and watch the shadows changing over different times of the day in our design. |
So, in summary, the sequence when working in 3-D is:
- Construct a wire-frame model. Try simple extrusions first, then surface meshes.
- Apply hidden-line removal to the image while you build the model.
- Apply shaded to the model when nearing completion.
- Finally render the image
Cost of courses
-
Online learning via broadband- fast Internet connection required.
The most popular option is to take a course by online learning at http://www.softwaretutor.designcad.com.au. The cost is $AUD75.00 for >30 hours of high quality training. These broadband leaning courses feature rapid enrolment if you pay by Paypal, lots of multi media instructional materials, online forums, multi choice reviews, questionnaires, submission of assignments etc. This is an enhanced learning experience at an affordable price. Click here to visit our broadband online learning site and click on the blue information button to sample a course.
-
One-on-one training (Adelaide or Canberra - in our offices or yours).
We can provide face-to face training. Each course takes one day and costs $AUD550.00. We do require some information about what it is that you or your organisation hopes to achieve by training so that we can prepare appropriate materials in advance of the course.
Each participant in one-on-one full day courses is automatically enrolled at no extra cost in the broadband learning version of the matching course (at either softwaretutor.net or landscapetutor.net). This would normally cost an additional $250.00 per person. In this way, students get a double benefit - personal tuition and the ability to access any of the written instructional materials online, replay any of the demonstration movies, download sample files, log questions, take quizzes and submit assignments for review.
|
|
As part of our continuing drive to reduce our carbon emissions by using digital delivery, we include a PDF version of your course. |
About our courses & methodology
Experience over many years has taught us that adults learn best by progressing through a course of study at their own pace and at times that suit them. Wherever possible, they like to learn by working on their own materials, rather than work through long practice exercises. Our courses are specifically designed so that this can occur- we introduce a topic, provide a movie which shows you how to do it and then give detailed step-by-step instructions for you to follow.
Locations
Courses may be taken at Regency Park, South Australia, in Canberra in hired facilities, or by distance learning or broadband learning. If a course is taken 'in-house' at Regency Park, it normally runs for a whole day with a break for lunch. Starting time is 9.15 am and finish time around 4.15 - 4.30 pm. We work one-on-one and supply tea and coffee and lunch.
Course duration:
When taken in-house, 3-D CAD normally runs over a full day session. When taken externally, experience has shown us that students take significantly longer to complete the course, primarily because they are able to break up their learning into small 'chunks' as time permits. AutoCAD and IntelliCAD are large programs - please allow plenty of time to work through our materials. We would estimate that you have 40-50 hours of work in front of you!