IBM RT Series Hardware Reference Manual page 361

TNL SN20-9844 (March 1987) to 75X0235
Vector Draw With Ending Null (X'36')
This graphic operation functions in exactly the same way and with the same parameters as the
preceding vector draw graphic operation type X'3S'. The only exception being that the ending
pel of the line is not written to the bit map. Used for polyline XOR.
Relative Draw With Ending Null (X'2C')
The relative draw with ending null graphic operation allows the user to specify the next vector
to be drawn as a delta or increment from the last end point specified and end with a null point.
Logic functions are the same as type X'3S'.
Example: Relative Draw with Ending Null (Xl and YI values are from current contents of RI
and RO).
Queue Queue Action
By
Function
Address Data Queue Processing
Que Ptr X'SIOO' Load DX into RS
Que Ptr-l
X'6200'
Load DY into R6
Que Ptr-2 X'D2CO' Execute relative draw with RS
=
Xl
+
DX
ending null.
R6
=
YI
+
DY
Draw vector from (X I, Y I)
to (Xl
+
DX,YI
+
DY)
w/END NULL
Extended Monochrome Graphics Adapter 49