SH7764 Datasheet, PDF (1145/1752 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC Engine Family SH-4A Series

Section 23 G2D
(6) 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 is only performed on the pixels at coordinates Y = 0, X =
0, 2, 4, 6, 8… and Y = 1, X = 1, 3, 5, 7, 9….
This function enables the drawn figure and ground to be mutually semi-composed.
The net drawing specification can be used with the POLYGON4 type, LINEA, LINEB, LINEC,
RLINEA, RLINEB, and RLINEC commands. The NET bit should be cleared to 0 in other
commands. The NET bit cannot be used together with the antialias enable bit (AA).
(7) 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 drawing specification (NET). With
the LINEWC and RLINEWC commands, drawing is performed at the work coordinates with 0
when EOS = 0, and with 1 when EOS = 1.
(8) Work Specification (WORK)
When drawing is performed at rendering coordinates with the POLYGON4 type or BITBLT type
command, the WORK bit can be used to select, on an individual drawing command basis, whether
or not binary work data is to be referenced.
When binary work data referencing is selected, drawing is performed if the work data for the pixel
corresponding to the rendering coordinates is 1, but not if the work data is 0. The same shape as
that drawn at work coordinates can thus be drawn at rendering coordinates. Drawing at work
coordinates can be performed either by means of the FTRAPC, RFTRAPC, LINEWC,
RLINEWC, or CLRWC command or else by the CPU. Ensure that memory drawing access by a
command and memory drawing access by the CPU are not performed simultaneously. The work
specification can be used with the POLYGON4 type, and BITBLT type, commands. The WORK
bit should be cleared to 0 in the other commands.
Rev. 1.00 Nov. 22, 2007 Page 1089 of 1692
REJ09B0360-0100