Generation of random mazes via backtracking. This program is a port of the example written in XC=BASIC 3.1 by JJ Flash, with the addition of a “mouse” that moves inside the maze in search of the “cheese”.

 
     DEFINE DEFAULT TYPE SIGNED WORD
 
     VAR finalScrPosition AS WORD
 
     CONST wall = 95 : CONST space = 32 : CONST mouse = 81
 
     VAR nextDirection AS BYTE: VAR firstnextDirection AS BYTE
 
     DIM dirArray(4) = #{ 2, -80, -2, 80 }
 
     PRINT "press a key (i need randomness)"
     WAIT KEY
 
     CLS BLACK
     INK WHITE
 
     RANDOMIZE TIMER
 
     restart:
     FOR i = 0 TO 999: POKE Txa+i, wall: NEXT
     FOR i = 0 TO 39: POKE Txa+i, space: NEXT
     FOR i = 0 TO 39: POKE Txa+984+i,space: NEXT
 
     screenPosition = Txa+79
     FOR i = 1 TO 23
         POKE screenPosition, space
         screenPosition = screenPosition + 40
     NEXT
 
     steps = 0 : maxSteps = 0
 
     screenPosition = Txa + 81 + (80 * RND(9)) + 2 * RND(9)
 
     POKE screenPosition, 4 : ' "D"
 
 digAnotherLocation:
         nextDirection = RND(3) : firstnextDirection = nextDirection
         IF steps > maxSteps THEN : maxSteps = steps: finalScrPosition = newScreenPosition : ENDIF
 
 tryDiggingAgain:
         newScreenPosition = screenPosition + dirArray(nextDirection)
         IF PEEK(newScreenPosition) = wall THEN
             POKE newScreenPosition, nextDirection
             POKE screenPosition + ( dirArray(nextDirection)\2 ), space
             screenPosition = newScreenPosition
             steps = steps + 1
             GOTO digAnotherLocation
         ENDIF
 
         nextDirection = (nextDirection + 1) AND 3
         IF nextDirection <> firstnextDirection THEN : GOTO tryDiggingAgain : ENDIF
         
         nextDirection = PEEK(screenPosition) : POKE screenPosition, space
         steps = steps - 1
         IF nextDirection < 4 THEN
             screenPosition = screenPosition - dirArray(nextDirection)
             GOTO digAnotherLocation
         ENDIF
         
         POKE screenPosition, 1 : POKE finalScrPosition, 2
         HOME : PRINT "max steps: " ; maxSteps ; " - final loc: " ; finalScrPosition
         
         POKE screenPosition, mouse : nextDirection = 2
 mouseLabel:
         WAIT VBL
         newScreenPosition = screenPosition + (dirArray(nextDirection)\2)
         IF newScreenPosition = finalScrPosition THEN : GOTO restart : ENDIF
         IF PEEK(newScreenPosition) = space THEN
             POKE newScreenPosition, mouse : POKE screenPosition, space
             screenPosition = newScreenPosition
             nextDirection = (nextDirection - 2) AND 3
         ENDIF
         nextDirection = (nextDirection - 1) AND 3
         GOTO mouseLabel
 
 

• contrib_mazegen.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 contrib_mazegen.bas -o example.xex
 altirra example.xex
 
 # Windows 
 ugbc.atari.exe contrib_mazegen.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 contrib_mazegen.bas -o example.xex
 altirra example.xex
 
 # Windows 
 ugbc.atarixl.exe contrib_mazegen.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 contrib_mazegen.bas -o example.prg
 x64sc example.prg
 
 # Windows 
 ugbc.c64.exe contrib_mazegen.bas -o example.prg
 x64sc example.prg

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.c64reu contrib_mazegen.bas -o example.prg
 x64sc -reu example.prg
 
 # Windows 
 ugbc.c64reu.exe contrib_mazegen.bas -o example.prg
 x64sc -reu 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 contrib_mazegen.bas -o example.prg
 yape example.prg
 
 # Windows 
 ugbc.plus4.exe contrib_mazegen.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 contrib_mazegen.bas -o example.prg
 xplus4 example.prg
 
 # Windows 
 ugbc.plus4.exe contrib_mazegen.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 contrib_mazegen.bas -o example.bin
 xroar -rompath (your rom path) example.bin
 
 # Windows 
 ugbc.d32.exe contrib_mazegen.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 contrib_mazegen.bas -o example.bin
 xroar -rompath (your rom path) example.bin
 
 # Windows 
 ugbc.d64.exe contrib_mazegen.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 contrib_mazegen.bas -o example.k7
 dcmoto
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
 
 # Windows 
 ugbc.pc128op.exe contrib_mazegen.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 contrib_mazegen.bas -o example.k7
 dcmoto
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
 
 # Windows 
 ugbc.pc128op.exe contrib_mazegen.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 contrib_mazegen.bas -o example.prg
 xvic --memory 24k example.prg
 
 # Windows 
 ugbc.vic20.exe contrib_mazegen.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 contrib_mazegen.bas -o example.tap
 Speccy example.tap
 
 # Windows 
 ugbc.zx.exe contrib_mazegen.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 contrib_mazegen.bas -o example.rom
 openmsx -cart example.rom
 
 # Windows 
 ugbc.msx1.exe contrib_mazegen.bas -o example.rom
 openmsx -cart example.rom

 # Linux 
 ugbc.msx1 contrib_mazegen.bas -o example.rom
 bluemsx example.rom
 
 # Windows 
 ugbc.msx1.exe contrib_mazegen.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 contrib_mazegen.bas -o example.rom
 openmsx -machine \"COL - ColecoVision\" -cart example.rom
 
 # Windows 
 ugbc.coleco.exe contrib_mazegen.bas -o example.rom
 bluemsx -machine \"COL - ColecoVision\" example.rom

 # Linux 
 ugbc.coleco contrib_mazegen.bas -o example.rom
 bluemsx /machine \"COL - ColecoVision\" /rom1 example.rom
 
 # Windows 
 ugbc.coleco.exe contrib_mazegen.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 contrib_mazegen.bas -o example.rom
 bluemsx /machine \"SEGA - SC-3000\" /rom1 example.rom
 
 # Windows 
 ugbc.sc3000.exe contrib_mazegen.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 contrib_mazegen.bas -o example.rom
 bluemsx /machine \"SEGA - SG-1000\" /rom1 example.rom
 
 # Windows 
 ugbc.sg1000.exe contrib_mazegen.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!