The range of pictures, drawings and images which can be produced by a computer are called graphics. The main types of graphics packages are painting, drawing, photo editing and CAD. There may be some cross over between the packages, ie certain packages may be suitable for more than one task.
A painting application [application: applications serve a specific purpose, eg Microsoft Word is used for word processing ] allows freehand drawing and colouring, usually with a mouse. Generally the features are:
- a palette from which the user can choose colours
- freehand pens and brushes offering different styles and line thickness
- a range of standard shape tools such as rectangles and circles
- colour fill tools
- spray cans and eraser tools
- cut, copy and paste
- zoom (to work in finer detail)
Bitmap graphics made with painting packages consist of many tiny dots called pixels. It is possible to edit each individual pixel.
Since the computer has to store information about every single pixel (the colour for example) in the image, the file size of a bitmap graphic is often quite large. Bitmap graphics lose quality when they're resized.
To resize the bitmap graphic below drag the slider from left to right or click the righthand magnifying glass.
Images made with drawing packages consist of lines, shapes and co-ordinates. Drawing packages are also known as vector drawing packages. Generally a drawing package offers many similar features to a painting.
Vector graphics are based on mathematical relationships with control points that make up the image, information is not stored about each pixelpixels: tiny dots that together form an image. These points are connected by lines and curves called vector paths or vectors.
A vector object is a shape made up of vector paths. It is possible to edit each object separately, for example, change the shape, stroke, fill, size and position. A stroke follows the outline of the vector path and a fill adds…