PDFlib 8 Windows COM/.NET Tutorial

HKS® colors. The HKS color system is widely used in Germany
and other European countries. PDFlib fully supports HKS
colors. All color swatch names from the following digital color
libraries (Farbfächer) can be used (sample swatch names are
provided in parentheses):
> HKS K (Kunstdruckpapier) for gloss art paper, 88 colors
(HKS 43 K)
> HKS N (Naturpapier) for natural paper, 86 colors (HKS 43 N)
> HKS E (Endlospapier) for continuous stationary/coated, 88 colors (HKS 43 E)
> HKS Z (Zeitungspapier) for newsprint, 50 colors (HKS 43 Z)
Commercial PDFlib customers can request a text file with the full list of HKS spot color
names from our support.
Spot color names are case-sensitive; use uppercase as shown in the examples. The
HKS prefix must always be provided in the swatch name as shown in the examples.
Generally, HKS color names must be constructed according to one of the following
schemes:
HKS
where is the identifier of the color (e.g., 43) and the abbreviation of the
paper stock in use (e.g., N for natural paper). A single space character must be provided
between the HKS, , and components constituting the swatch name. If a
spot color is requested where the name starts with the HKS prefix, but the name does
not represent a valid HKS color a warning is logged. The following code snippet demonstrates
the use of an HKS color with a tint value of 70 percent:
spot = p.makespotcolor("HKS 38 E");
p.setcolor("fill", "spot", spot, 0.7, 0, 0);
User-defined spot colors. In addition to built-in spot colors as detailed above, PDFlib
supports custom spot colors. These can be assigned an arbitrary name (which must not
conflict with the name of any built-in color, however) and an alternate color which will
be used for screen preview or low-quality printing, but not for high-quality color separations.
The client is responsible for providing suitable alternate colors for custom spot
colors.
There is no separate PDFlib function for setting the alternate color for a new spot color;
instead, the current fill color will be used. Except for an additional call to set the alternate
color, defining and using custom spot colors works similarly to using built-in
spot colors:
p.setcolor("fill", "cmyk", 0.2, 1.0, 0.2, 0); /* define alternate CMYK values */
spot = p.makespotcolor("CompanyLogo"); /* derive a spot color from it */
p.setcolor("fill", "spot", spot, 1, 0, 0); /* set the spot color */
3.5 Working with Color 83