208
The
VIC
20
User
Guide
710
FOR
1=7168
TO
7183
:
READ
X :
POKE
I,X
NEXT
I
720
DATA
3,3,3,1,7,15,23,23
730
DATA
128,136,136,8,248,1'2,1'2,1'2
740
REM
LOAD
BOTTOM
HALF
OF
PLAYER
750
FOR
1=7344
TO
735' :
READ
X :
POKE
I,X
NEXT
I
760
DATA
19,19,2,2,2,2,6,O
770
DATA
128,128,128,128,128,128,192,0
780
REM
LOAD
'EXTRA
ARMS,'
790
FOR
1=7192
TO
7207
:
READ
X :
POKE
I,X
NEXT
I
800
DATA
128,128,132,8,240,1'2,192,1'2
810
DATA
128,128,128,O,252,192,192,192
820
RETURN
When you
run
the program, the stick man on the left side
of
the screen
starts waving. After a moment, the one
at
the right starts to wave back. Then
the
man
on
the left stops waving, followed by the one
on
the right,
and
the
cycle repeats.
The three subroutines
that
make the men wave (lines 210,310,
and
490)
are the key
to
the motion. The first one, starting at line 210, makes only the
figure
on
the left wave.
The second subroutine, which begins with line 310, causes
both
ofthe
men to wave. Notice that the
man
on the left moves, then the program
pauses for
about
half the time it did when moving just one
arm
before
moving the
man
on
the right. After the right-hand man's
arm
moves, the
program again delays only half as long as before. This keeps the men moving
at
about
the same speed, even though both are waving together. The man
on
the right also waves in the opposite direction from the man
on
the left, so
they
don't
appear to be moving in "lock-step" with each other. These small
differences make the display more interesting.
The last subroutine, starting
at
line 490, moves only the right-hand stick
man, so the one
on
the left stops waving.
HIGH·RESOWTION
GRAPHICS
With high-resolution graphics, your program deals with individual
dots
on
the screen, instead
of
characters. High resolution can be used to
draw finer lines on. the screen
or
to smooth the motion
of
a player, since it
can move in increments
of
one dot, instead
of
a whole character space.
Using high-resolution graphics
on
the VIC
is
much like using custom
characters.
In
fact, to the VIC chip, they are exactly the same; the standard
character display
is
a high-resolution display. The main difference
is
one
of
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