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No style specification (STYL = 0)
Style specification used (STYL = 1)
Source data
Figure 4-14
Net Drawing Specification (NET): The NET bit can be used to select, on an individual
drawing command basis, whether or not net drawing is to be performed. Net drawing is a function
for drawing only pixels at coordinates for which the condition "rendering coordinates X + Y = EOS
(0: even number, 1: odd number)" is true. For example, if EOS = 0, drawing will only be
performed at coordinates Y = 0, X = 0, 2, 4, 6, 8, ..., Y = 1, X = 1, 3, 5, 7, 9, ...
This function enables the drawn figure and ground to be mutually semi-superimposed.
The net drawing specification can be used with the POLYGON4 commands, and the LINE,
RLINE, PLINE, and RPLINE commands; it is invalid for other commands.
Source Half Drawing Specification (HALF): The HALF bit can be used to select
whether all or only half of the source data is to be referenced. When the source half drawing
specification is selected, only EOS (0: even number, 1: odd number) data is referenced from the
source starting point. Thus only half of the source data in the horizontal direction is referenced.
The source half drawing specification can only be used with the POLYGON4B (binary source)
command, and is invalid for other commands.
Even/Odd Select Specification (EOS): Even pixels are selected when EOS = 0, and odd
pixels when EOS = 1.
The even/odd select specification is used together with the net specification or source half
specification.
With the LINEW and RLINEW commands, drawing is performed at the work coordinates with 0
when EOS = 0, and with 1 when EOS = 1.
Examples of even/odd select specifications are shown in figure 4-15.
Drawing data
Example of Source Style Specification
Enlarged by factor of 2
Referenced twice
73
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