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2. Graphics terms

Pixel

or 'picture element' refers to a small rectangular part of an image. It has some attributes associated, e.g. a certain color, texture etc, which are assumed to be constant over the whole area covered by it. All pixels are assumed to have the same shape and size. A pixel is the smallest element of a picture that can be controlled independently of the other pixels in its attributes.

Dot

is the smallest unit that can be addressed for an image. For uniform pixels this may be the pixel itself; for textured pixels, such as character glyphs, a dot is a pixel of the texture which is assumed to be uniform. We will use this to refer to sub-pixel coordinates, e.g. for a graphical pointer in textmode. As with pixels, dots are assumed to have the same shape, size, color and intensity over the whole area covered. They have only a uniform texture.


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