HP Vectra Technical Reference Manual page 138

4.3.4 Hardware Interface Level Services
Service drivers are provided as useful subroutines available to any driver. Currently the hardware
interface level has only one service, the tracking sprite, V_STRACK. (For more information on
sprites see Section 6).
4.3.4.1 V_STRACK Driver (BP
=
OOOSAH)
V_STRACK is called by the logical GID drivers to move the graphics cursor (sprite) on the display
screen. V_STRACK provides functions that allow the parameters of the sprite to be defined, and
move the sprite around the display.
A summary of the V_STRACK function codes is provided in table 4.20.
Table 4.20
~
V_STRACK Driver Function Code
Summary
Vector Func. Function
Address
Value Equate Definition
OOSAH
V_STRACK
Sprite control
OOSAH
02
F_SYSTEM
System functions
OOSAH
02/00
SF_INIT
Initialize driver
OOSAH
02/02
SF_START
Start driver
OOSAH
04 F_TRACLINIT Sets tracking to default state
OOSAH
06 F_TRACLON Enables tracking
OOSAH
08
F_TRACLOFF Disables tracking
OOSAH
OA F_DEF_MASKS
Define sprite masks
OOSAH
OC F_S ET_LI M ITS----><
Set max/min horizontal values
OOSAH
DE
F_SET_LI M ITS_Y
Set max/min vertical values
OOSAH
10
F_PUT_SPRITE
Display sprite
OOSAH
12
F_REMOVE_SPRITE
Remove sprite from display
Input System and HP-HIL 129