The Scale Factors control contains four boxes that specify horizontal and vertical scale factors for raster graphics and text output using device fonts. Unlike all other values specified in the minidriver, the scale factors are expressed in dots per inch rather than master units. However, the values specified must still factor evenly into master units.
Text scale factors are used to describe the resolution at which device fonts were digitized, and graphic scale factors are used to describe the resolution at which individual pixels are placed upon the page. However, since graphic scale factors are tracked internally as logarithmic ratios to text scale factors, graphic scale factors must always either be equal to the text scale factors or equal to a text scale factor divided by a power of 2. For example, a text scale factor of 300 dots per inch may use a graphic scale factor of 300, 150 (300/2), of 75 (300/4), but not a graphic scale factor of 100.
For most laser printers, text and graphics are sent to the printer in separate bands. The coordinates of where each object will be placed in a given band on the page are based upon these scale factors. For example, the HP LaserJet IIP supports one of several resolutions with an x and y text scale factor of 300 dots per inch, and a graphics scale factor of 75 dots per inch. When using this resolution, text printed using device fonts output will be at 300 dpi accuracy, but raster graphic objects output will be at 75 dpi accuracy.
For most dot-matrix and ink-jet printers, text and graphics are sent to the printer in the same band. The coordinates for placement in a given band are based upon the graphic scale factors. For these printers, the text and graphic scale factors should always be the same. Attempting to set different scale factors will not change output quality, and will cause Windows to not enumerate TrueType fonts when this resolution is selected.
Note:
TrueType fonts will not be available for those resolutions where the text scale factor does not equal the graphic scale factor unless the driver supports downloading TrueType fonts. For more information about downloading fonts, see Section 7.6, “Specifying Downloadable-Font Commands and Data.”
For the Diconix 150 Plus minidriver, the text and graphics resolutions are identical; therefore, the X DPI boxes contain the value 320 and the Y DPI boxes contain the value 96.
For the HP LaserJet IIP minidriver, the device fonts were digitized at the highest printer resolution (300 dpi); therefore, at the highest graphics resolution, each Scale Factors box contains the value 300.