Loadstar 18/018.d81/t.sprites.128

Text File | 2022-08-26 | 5KB | 305 lines

      128 SPRITES AND UTILITIES
      *************************


Written by:  Louis F. Sander

Microcomputers Magazine, December 1985
Page 46


  In the 128, the memory locations

from 3584-4095 are reserved for eight

sprites, each using 64 bytes. These

locations hold only the shape of the

sprites; other attributes are

separately controlled by BASIC's

SPRITE statement. The eight sprites

are located as follows:

Sprite     Decimal      Hexidecimal
======    =========     ===========
  1       3584-3647     $0E00-$0E3F
  2       3648-3711     $0E40-$0E7F
  3       3712-3775     $0E80-$0EBF
  4       3776-3839     $0EC0-$0EFF
  5       3840-3903     $0F00-$0F3F
  6       3904-3967     $0F40-$0F7F
  7       3968-4031     $0F80-$0FBF
  8       4032-4095     $0FC0-$0FFF


  Regardless of what is in the sprite

memory, the 128 treats it as a

sprite; therefore, it is up to you to

know which sprite has meaning. To see

what's in the sprite area at power

up, enter:

FORJ=1TO8:SPRITEJ,1,2
MOVSPRJ,35*J,200:NEXT [RETURN]

 You have just made all eight sprites

white and printed them on the bottom

of the screen. Their shapes are

determined by whatever was in their

locations at the 128's power up. To

make them into squares, enter:


FORJ=3584TO4095
POKEJ,255:NEXT [RETURN]


      SAVING AND LOADING SPRITES
======================================

 To save and load sprites to and from

disk, use the BSAVE and BLOAD

commands. To save your squares to

disk, enter:

BSAVE"SQUARES.SPR",B0,P3584
TO P4096 [RETURN]

 Be sure to type it as shown; one of

the examples in your system guide

contains an error. Use the .SPR to

identify sprite files in the

directory. This identification is

important, because sprite files must

be BLOADed and not DLOADed which

causes them to crash.

     CONTROLLING THE SPRITES
======================================

 To turn your sprites on, use:

SPRITEx,1,z where x specifies the

sprite you are controlling and z is a

number from 1 to 16, corresponding to

the color you want the sprite to be.

 To turn off your sprite, enter:

SPRITEx,0 where x specifies the

sprite you wish to turn off.

 To move your sprite around, use the

MOVSPR statement. Since this

statement is complex, we will not

discuss it here. Refer to section 17

of your manual.


         CREATING SPRITES
======================================

 To design your own sprites, you have

three options:

  1. Use SPRDEF, the built-in sprite
     editor program.
  2. Use the 128's high-resolution
     graphics commands to create a
     design on the screen, then use
     the SSHAPE and SPRSAV commands
     to turn it into a sprite.
  3. Use the tried and true methods
     that work with the 64.

 For a detailed description of SPRDEF

study pages 116-119 and page 293 in

your system guide. Keep in mind that

when SPRDEF says "saving" sprites, it

means storing them in memory.

 Pages 109-116 give examples of using

SSHAPE and SPRSAV, both are also

explained in section 17. However, in

these lines there is a minor bug that

causes the sprites to keep moving

even after you hit STOP/RESTORE. To

improve this program add these

lines:

 6 COLOR 1,8 : TRAP99
96 MOVSPR 1,0#0 : SPRITE 1,0
97 MOVSPR 2,0#0 : SPRITE 2,0

 For the 64 method, it is best to

study the 64's Programmer's Reference

Guide, plus the many articles that

have been written on sprites.


             UTILITIES
======================================

  On Side 2 of this LOADSTRAR disk,

there are five useful tools for

managing your sprites. They are:

SPRITESEER.128; NUMBERS.BAS.128;

SPRITESAVER.128; HBARMULTI.128; and

VBARMULTI.128.

  SPRITESEER.128 displays stationary

sprites on the bottom of the screen

and allows you to manipulate their

attributes. At the top of the screen,

the program prints line 110, followed

by a line containing "RUN". On line

110, set E=1 to expand the sprites in

the X and Y directions. To make them

multicolor, set M=1. If you want all

sprites to have the same color, then

change the third argument in the

SPRITE statement, on line 120, to

that color.

 NUMBER.BAS.128 makes and BSAVEs

sprites that are labeled with their

numbers. Very useful for testing

purposes.

 SPRITESAVER.128 lets you BSAVE all

the sprites, one sprite, or a

selected group of sprites. You answer

the prompts to specify which sprite

or group of sprites.

 HBARMULTI.128 creates and saves

sprites which, in Multicolor mode,

appear as flags with horizontal bars

in three colors: sprite color;

Multicolor 1; and Multicolor 2. If

you are familiar with the literature

on sprites then you will understand

the use for such a tool. If not, I

urge you to delve into it.

 VBARMULTI.128 does similiar to

HBARMULTI.128 except that the bars

are vertical instead of horizontal.

In both of these programs, if you are

in single-color mode these sprites

will have quite a different

appearance.


   This program is copyrighted by

Commodore magazine.  All rights to it

are reserved.  LOADSTAR has relieved

you from the burden of keying in this

    program.  For more complete

information about this program, refer

   to the December 1985 issue of

     Microcomputers Magazine.



>Files used: SPRITESEER.128
             NUMBER.BAS.128
             SPRITESAVER.128
             HBARMULTI.128
             VBARMULTI.128

---------< end of article >-----------