This Page Last Updated And Links Checked: 28 June 2003 This Page Last Updated And Links Checked: 28 June 2003 What is AutoCad And Why Do I Need it?
AutoCad is an example of graphics software that produces 'vector graphics' as opposed to the more common 'raster graphics' based on coloring pixals as used by 'paint' software. It may be over simplification but raster graphics are intended to be attractive to look at, or give an indication of what something looks like while a vector package like Autocad or similar is required to draw anything that is intended to be built or manufactured because it has the facility and the precision to convey the drawer's exact requirements to the builder or manufacturer.
Speaking and writing are the main modes of communication for many people and while we acknowlege a 'picture is worth a thousand words' the advent of the reasonably priced, powerful home computer provides the opportunity to be able do drawings using software cheaply or freely downloaded from the internet that produce results that a few years ago would have required prohibitively expensive workstations and highly skilled operators.
These days 'doing a drawing' can now be extended to include designing, modelling, prototyping and confirming the attractiveness, functioning and fitness for purpose of an item that has been created relatively cheaply in 'cyberspace' and can be the basis for further input from proposed users, clients, marketing personel, manufacturing experts or even regulatory autorities before expensive manufacturing or building is undertaken.
AutoCad is a software package I use to produce useful drawings, as opposed to pretty pictures. It produces vector images which means each line, circle or object you draw is recorded as an equation (remember your high school maths). Additional information is also recorded such as start-end points, line thickness, color and layer (layers can be switched on or off so you can view particular parts of a complicated drawing). It is all saved as a text file which can be viewed in NotePad or Wordpad.
You can edit the text file and see the changes reflected in the drawing. In this sense there are similarities with a WYSIWYG authoring package used to create a web page directly on the screen which generates an html (text) file that too can be edited with a text editor to change the "rendering" of the web page.
Generally speaking all other graphics or images produced on a computer are called raster images. A raster image is made up of coloured pixels. A record is kept of the colour assigned to each pixel (one pixel ..one colour). This one to one relationship in math talk is often called a "mapping" hence the term "bit mapped image" (ie a .bmp). other formats such as .gif, .jpg or .png try to achieve a comparable result in a smaller file size.
If you came up the raster image track via Kidpix, Paint, PaintShop Pro and beyond, then, maybe you now make graphics to enhance the appearance of websites or even stand alone as art. Sadly, graphics are easily abused and excessive or distractive graphics may be a signal that the site has little content of substance.
If you came up the equation track via turtle drawing packages and using line and draw commands in Basic programing, then, maybe you now use a CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) package, such as Autocad, to produce both drawings and the code which can used as input to machines to make anything from component parts, clothing, computer chips (computers!), furniture or whatever (ie Computer aided Manufacture or CAM). The drawings themselves may be the specification for building homes, buildings, roads, bridges, boats, ships, aircraft, dams or machines used to make these or other things ..the list is endless.
You can do simple 2D drawings to draw that B.B.Q area you were always going to build or you could make complex 3D models of a new fighter-bomber for the air-force which would take a little longer to do and require some specialist knowledge. If designing a boat, piece of machinery or building for example you may choose to expend a lot of effort "surfacing" your 3D drawing model and use light and shade effects to make it appear so real that the term "photo realism" is used. More basic 3D models help visualise alternate concepts, aid in the design process and be the basis for producing the 2D drawings required in the manufacturing process. Interestingly, good photo realistic 3D images can be used to sell a concept, gauge consumer reaction or in advertising material before the detailed design necessary for production is undertaken.
Overall the trend is for the raster packages, such as Paintshop Pro7, to introduce layers and equation based control over some portions of the graphic to increase efficiency while the equation based packages, such as AutoCAD, have provided for integrating raster images into the drawing to make it a more complete representation of what is being proposed, trying to show the design in it's proposed location scanned from a photo for example or to represent complex components that consume a lot of memory such as helix threads or springs for exambple.
If you live in Sydney (Australia) I can recommend some low cost AutoCad 2000+, Mechanical Desktop or FEA (finite element analysis) courses. The training is in computer laboritory group of about 12 participants at an evening college.
If you have an employer and that employer is happy to pay for you to attend full time training during working hours (lucky you) then get onto Autodesk for an Autodesk approved trainer. They provide lunch and you get home earlier than if you were at the office.
Also check out your local community or public education systems, particularly if you are a student, retired, trying to make yourself more employable or don't have an employer who will send you on a course. In any case one or two nights a week for a few hours may better suit the learning needs of some, has an ongoing social aspect and working through a syllabus can result in exposure to aspects of the package you are unfamliar with if you have been working continously in a particular disipline.
Contact: Aussie John wpsmoke@yahoo.co.uk