Logic Operation; Hidden Plane Management - Fujitsu MB86R02 Jade-D Hardware Manual

MB86R02 'Jade-D' Hardware Manual V1.64
18.10.5.3

Logic operation

This mode executes a logic operation between the pixel to be drawn and the one already drawn in
frame buffer and its result is drawn. Alpha blending cannot be used when this function is specified.
Type
CLEAR
COPY
NOP
SET
COPY INVERTED
INVERT
AND REVERSE
OR REVERSE
18.10.5.4

Hidden plane management

MB86R02 'Jade-D' supports the Z buffer for hidden plane management.
This function compares the Z value of a new pixel to be drawn and the existing Z value in the Z buffer.
Display/not display is switched according to the Z-compare mode setting. Define the Z-buffer access
options in the ZWRITEMASK mode.
The Z compare operation type is determined by the Z compare mode.
Either 16 or 8 bits can be selected for the Z-value.
ZWRITEMASK
Z Compare mode
NEVER
ALWAYS
LESS
LEQUAL
EQUAL
GEQUAL
GREATER
NOTEQUAL
ID Operation
0000 0
0011 S
0101 D
1111 1
1100 !S
1010 !D
0010 S & !D
1011 S | !D
1 Compare Z values, no Z value write overwrite
0 Compare Z values, Z value write
Code Condition
000 Never draw
001 Always draw
010 Draw if pixel Z value < current Z buffer value
Draw if pixel Z value ≤ current Z buffer value
011
100 Draw if pixel Z value = current Z buffer value
Draw if pixel Z value ≥ current Z buffer value
101
110 Draw if pixel Z value > current Z buffer value
111 Draw if pixel Z value ! = current Z buffer value
Type ID
AND 0001
OR 0111
NAND 1110
NOR 1000
XOR 0110
EQUIV 1001
AND INVERTED 0100
OR INVERTED 1101
Operation
S & D
S | D
! (S & D)
! (S | D)
S xor D
! (S xor D)
!S & D
!S | D
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