Scaling Vector Files

A vector element may be scaled to any size. Precision, overflow, and underflow problems may occur, however, if vector data is scaled too large or too small, "large" and "small" being relative to the intrinsic data size of the hardware and software platform supporting the rendering application. Although these problems are well known in numerical analysis, they are not generally recognized by the majority of programmers, and it pays to keep them in mind.

Another common problem occurs when apparently enclosed elements are enlarged and then rendered. Two lines meant to be joined may have endpoints slightly misaligned, and this misalignment may show up as a gap when the element is enlarged or rotated. When a rendering application attempts to display the element on an output device, fill colors or patterns may inexplicably "leak." Many applications that allow the creation of vector files have tools to prevent this, but they may not be applied automatically before the file is saved.



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