This example shows how to move sprites by using the multitasking feature, assigning a movement routine to each sprite, and inside a game loop, to improve performances on VBL constaint systems.

 
 BITMAP ENABLE (2)
 
 CONST spriteCount = 8
 
 DEFINE TASK COUNT spriteCount
 
 DIM sprites AS SPRITE (spriteCount)
 DIM x AS POSITION (spriteCount)
 DIM y AS POSITION (spriteCount)
 
 spriteImage = LOAD IMAGE("drop.png")
 
 GLOBAL sprites,x,y,spriteImage
 
 drops = 0
 dropskip = (BYTE) ( SPRITE HEIGHT * 2 )
 
 FOR i=0 TO spriteCount-1
     sprites(i) = SPRITE(spriteImage)
 NEXT
 
 BEGIN GAMELOOP
 
     PARALLEL PROCEDURE dropDown
         SPRITE [sprites] ENABLE
         DO
             [x] = RANDOM WIDTH
             FOR [y] = 0 TO SCREEN HEIGHT + IMAGE HEIGHT(spriteImage)
                 SPRITE [sprites] AT [x], [y] COLOR BLUE
             NEXT
         LOOP
     END PROC    
 
     IF drops < (spriteCount-1) THEN
         DEC dropskip
         IF dropskip = 0 THEN
             SPAWN dropDown
             dropskip = SPRITE HEIGHT
             INC drops
         ENDIF
     ENDIF
 
 END GAMELOOP

• sprites_example_03.bas

The instructions here refer to compiling the example from the command line. For Microsoft Windows users we suggest using UGBASIC-IDE, which allows you to compile the example with just one click.

In order to compile and run the example, you need to have the Altirra emulator, and in particular that the altirra executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.atari sprites_example_03.bas -o example.xex
 altirra example.xex
 
 # Windows 
 ugbc.atari.exe sprites_example_03.bas -o example.xex
 altirra example.xex

In order to compile and run the example, you need to have the Altirra emulator, and in particular that the altirra executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.atarixl sprites_example_03.bas -o example.xex
 altirra example.xex
 
 # Windows 
 ugbc.atarixl.exe sprites_example_03.bas -o example.xex
 altirra example.xex

In order to compile and run the example, you need to have the VICE emulator, and in particular that the x64sc executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.c64 sprites_example_03.bas -o example.prg
 x64sc example.prg
 
 # Windows 
 ugbc.c64.exe sprites_example_03.bas -o example.prg
 x64sc example.prg

In order to run the example, you need to have the YAPE emulator. In particular that the yape executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.plus4 sprites_example_03.bas -o example.prg
 yape example.prg
 
 # Windows 
 ugbc.plus4.exe sprites_example_03.bas -o example.prg
 yape example.prg

In order to run the example, you need to have the VICE emulator. In particular that the xplus4 executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.plus4 sprites_example_03.bas -o example.prg
 xplus4 example.prg
 
 # Windows 
 ugbc.plus4.exe sprites_example_03.bas -o example.prg
 xplus4 example.prg

In order to compile and run the example, you need to have the XROAR emulator, and in particular that the xroar executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.d32 sprites_example_03.bas -o example.bin
 xroar -rompath (your rom path) example.bin
 
 # Windows 
 ugbc.d32.exe sprites_example_03.bas -o example.bin
 xroar.exe -rompath (your rom path) example.bin

In order to compile and run the example, you need to have the XROAR emulator, and in particular that the xroar executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.d64 sprites_example_03.bas -o example.bin
 xroar -rompath (your rom path) example.bin
 
 # Windows 
 ugbc.d64.exe sprites_example_03.bas -o example.bin
 xroar.exe -rompath (your rom path) example.bin

In order to compile and run the example, you need to have the DCMOTO emulator, and in particular that the dcmoto executable is accessible.

Then, type this command on the command line and on the emulator:

 # Linux 
 ugbc.pc128op sprites_example_03.bas -o example.k7
 dcmoto
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
 
 # Windows 
 ugbc.pc128op.exe sprites_example_03.bas -o example.k7
 dcmoto
 (choose example.k7)
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC

In order to compile and run the example, you need to have the DCMOTO emulator, and in particular that the dcmoto executable is accessible.

Then, type this command on the command line and on the emulator:

 # Linux 
 ugbc.pc128op sprites_example_03.bas -o example.k7
 dcmoto
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
 
 # Windows 
 ugbc.pc128op.exe sprites_example_03.bas -o example.k7
 dcmoto
 (choose example.k7)
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC

In order to compile and run the example, you need to have the VICE emulator, and in particular that the xvic executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.vic20 sprites_example_03.bas -o example.prg
 xvic --memory 24k example.prg
 
 # Windows 
 ugbc.vic20.exe sprites_example_03.bas -o example.prg
 xvic --memory 24k example.prg

In order to compile and run the example, you need to have the Speccy emulator, and in particular that the speccy executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.zx sprites_example_03.bas -o example.tap
 Speccy example.tap
 
 # Windows 
 ugbc.zx.exe sprites_example_03.bas -o example.tap
 Speccy example.tap

In order to compile and run the example, you need to have the openMsx or the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.msx1 sprites_example_03.bas -o example.rom
 openmsx -cart example.rom
 
 # Windows 
 ugbc.msx1.exe sprites_example_03.bas -o example.rom
 openmsx -cart example.rom

 # Linux 
 ugbc.msx1 sprites_example_03.bas -o example.rom
 bluemsx example.rom
 
 # Windows 
 ugbc.msx1.exe sprites_example_03.bas -o example.rom
 bluemsx example.rom

In order to compile and run the example, you need to have the openMsx or the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.coleco sprites_example_03.bas -o example.rom
 openmsx -machine \"COL - ColecoVision\" -cart example.rom
 
 # Windows 
 ugbc.coleco.exe sprites_example_03.bas -o example.rom
 bluemsx -machine \"COL - ColecoVision\" example.rom

 # Linux 
 ugbc.coleco sprites_example_03.bas -o example.rom
 bluemsx /machine \"COL - ColecoVision\" /rom1 example.rom
 
 # Windows 
 ugbc.coleco.exe sprites_example_03.bas -o example.rom
 bluemsx  /machine \"COL - ColecoVision\" /rom1 example.rom

In order to compile and run the example, you need to have the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.sc3000 sprites_example_03.bas -o example.rom
 bluemsx /machine \"SEGA - SC-3000\" /rom1 example.rom
 
 # Windows 
 ugbc.sc3000.exe sprites_example_03.bas -o example.rom
 bluemsx  /machine \"SEGA - SC-3000\" /rom1 example.rom

In order to compile and run the example, you need to have the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

 # Linux 
 ugbc.sg1000 sprites_example_03.bas -o example.rom
 bluemsx /machine \"SEGA - SG-1000\" /rom1 example.rom
 
 # Windows 
 ugbc.sg1000.exe sprites_example_03.bas -o example.rom
 bluemsx  /machine \"SEGA - SG-1000\" /rom1 example.rom

If you have found a problem trying to run this example, if you think there is a bug or, more simply, you would like it to be improved, open an issue for this example on GitHub. Thank you!