Vector Files and Device Independence

As mentioned above, vector images are collections of device-independent mathematical descriptions of graphical shapes.

More so than their bitmap counterparts, various vector formats differ primarily because each was designed for a different purpose. While the conceptual differences between the designs of formats supporting 1-bit and 24-bit bitmap data may be small, the differences between vector formats used with CAD applications and those used for general data interchange can be formidable. Thus, it is difficult to generalize about vector formats in the same way we did when discussing bitmap formats.

On the other hand, most output devices are point-addressable, providing a grid of pixels which can be addressed individually, as if the surface of the device were graph paper made of discrete elements. This means that an application can always find a way to draw vector-format image elements on the device.



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