| | Graphics : Painting Packages | 
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Painting packages allow you to paint onto the screen as if it was a canvas. Many tools will be provided to help you do this. The most common tools are :
| Palette | Using the palette you can select the colours that you want to draw with. There will be a current colour which will be used when you draw anything onto the screen. |
| Freehand Brush | By moving the pointer around the screen you can draw directly onto the page using a brush. The width of the brush can be altered to produce thick or thin marks. |
| Straight Lines | It is very difficult to draw straight lines with a freehand brush. You would need a very steady hand to do this. Therefore a special straight line tool which will join up two points that you click on is usually available. |
| Shapes | Most painting packages also provide tools to draw a range of mathematical shapes such as circles and rectangles. These can be either filled in or drawn as outlines only. |
| Text | The text tool will let you enter text and place it onto the page in a variety of fonts. |
| Flood Fill | This tool will fill in an area of the screen with the current colour. If you click on a point on the image then all of the points surrounding it that are the same colour as the clicked on point will be filled with the current colour. |
| Zoom | You can zoom in on a particular area of the drawing so that you can see it in more detail. This will enable you to produce more accurate drawings by adding finer detail. |
Painting packages are the best type of package to use if you want to edit scanned images such as photographs.
Painting packages store images as a series of small dots called pixels. If you zoom far enough into the image you will be able to see the individual pixels. The colour of each individual pixel on the screen must be remembered and saved. Files storing the colours of each pixel in an image are known as bitmap files. Because so much information has to be stored files saved by painting packages are usually very large. An image the size of a typical computer screen (800*600 pixels) would take up over one megabyte of memory. Therefore images produced by painting packages are often stored in a special compressed format such as GIF or JPEG.
Painting packages have one major limitation. It is the same limitation that you will find if you try to paint a picture on canvas. This limitation is that once a mark has been placed onto an image it is extremely difficult to change it. The only way to erase a mark is to paint over it in the same colour(s) as the background. There is no simple way to move a mark from one position in an image to another. Most packages provide an undo feature so that you can erase one unwanted mark immediately after you have made it. But in general it is very difficult to edit an image with a painting package.
A further limitation of images produced by a painting package is that if you enlarge them too much then you will be able to see the individual pixels that make up the image. The image will look very blocky or pixelated.
GCSE ICT Companion 04 - (C) P Meakin 2004