With color printers becoming more affordable, many test engineers may like to show graphs in full color to more clearly illustrate a particular result. Limit envelopes can be shown in one color and line style, data in another. It may be desirable to produce color transparencies for overhead presentation that incorporate test graphs as well as explanatory text. Fortunately there are several easy to use Windows-based tools to do this and we intend to describe these in this article. First let's look at some basic graphical principles.
Graphical information is stored in one of two basic methods in personal computers.
One method stores all of the individual dots or pixels in the matrix that makes up an image. The file format .BMP or .PCX or .TIF are examples of these. An image stored this way is fixed in size and resolution. It cannot be easily reduced or expanded in size without unattractive results. An alternative method stores only the instructions that will draw the image.