The Canon imagePRESS C800 Series support the complete GOCA DR/2V0 subset. Some additional GOCA functions are also supported.
The GOCA line width is an integer (Set Line Width drawing order) or decimal (Set Fractional Line Width drawing order) multiplier of the normal line width. The normal line width (NLW) is approximately 0.01” or 10 mils (1 mils = 1/1000”).
With a 240 DPI print head resolution, the normal line width would be 2.4 pixels. After dropping the decimal, a one NLW wide line will be printed with 2 pixels or 8 mils instead of the ideal 10 mils. With a 300 DPI print head resolution, the normal line width is 3 pixels and with 600 DPI the normal line width is 6 pixels.
The appearance of the GOCA fill patterns is printer specific and may vary between different printer models. Applications printed on other IBM printers may therefore look slightly different when they are printed on a Canon printer. The GOCA patterns are rather coarse structures, not as fine as a colour screen. If you combine a GOCA pattern with a GOCA colour, the result will look different on different printers.
GOCA is a fully resolution-independent architecture; except for the GOCA raster image. A GOCA image is similar to an old IM1 type image, i.e. an uncompressed bitmap. Old GOCA images, created for either 240 or 300 DPI, can therefore only be printed with that resolution.