BITMAP ENABLE(16)
 
 CLS
 
 'ZXASCII
 'AUTO -1
 'PROG /demos/3D/lightsource_ball
 'CHANGED FALSE
 10 REM Sphere shader. Slow as. lx,ly,lz=light source coords
 ' 20 palette 255,$FFFFFF: rainbow 0 to 255: screen lock:
 ' for f=0 to 400: plot ink rnd*255;rnd*scrw,rnd*scrh: next f
 '30 
 llx = 0
 lly = 0
 xc=SCREEN WIDTH/3
 yc=SCREEN HEIGHT/2
 CONST r=32
 amb=0.03
 k=2
 n=10
 mxp=(1-amb)*256
 CONST r2=r*r
   
 '  DIM no(r*2+1,r*2+1) 
 
 INK WHITE
 
 PRINT "ok!"
 
 FOR x=-r TO r
 '   FOR y=-r TO r
 '      aaa = RND(n)
       'no(x+r,y+r)=aaa
       PRINT "ok2"
 '   NEXT
 NEXT
 
 'mousex=0
 'mousey=0
 
 'DO
 '   lx=xc-mousex
 '   ly=yc-mousey
 '   lz=-75
 
 '	IF lx<>llx OR ly<>lly THEN : GOSUB 1000 : ENDIF
 '	llx = lx
 '	lly = ly
 '	WAIT VBL
 'LOOP
 
 '1000 
 '	l=SQR(lx*lx+ly*ly+lz*lz)
 '	nlx=lx/l
 '	nly=ly/l
 '	nlz=lz/l
 '	FOR x=-r TO r
 '    	x2=x*x
 '    	FOR y=-r TO r
 '       		y2=y*y
 '       		IF x2+y2<=r2 THEN
 '          		v2=SQR(r2-x2-y2)
 '          		l=SQR(x2+y2+v2*v2)
 '          		v0=x/l
 '          		v1=y/l
 '          		v2=v2/l
 '          		d=nlx*v0+nly*v1+nlz*v2
 '          		DIM ppp AS SIGNED DWORD
 '          		IF d<0 THEN
 '          			ppp = -d^k
 '          		ELSE
 '          			ppp = 0
 '          		ENDIF
 '          		DIM qqq AS SIGNED WORD
 '          		DIM rrr AS FLOAT
 '          		qqq = ppp
 '          		rrr = qqq
 '          		i=mxp*(rrr+amb)-no(x+r,y+r)
 '          		PLOT x+xc,y+yc,i
 '           	ENDIF
 '        NEXT
 '    NEXT
 ' RETURN
 '
 
 

• contrib_rt.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_rt.bas -o example.xex
 altirra example.xex
 
 # Windows 
 ugbc.atari.exe contrib_rt.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_rt.bas -o example.xex
 altirra example.xex
 
 # Windows 
 ugbc.atarixl.exe contrib_rt.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_rt.bas -o example.prg
 x64sc example.prg
 
 # Windows 
 ugbc.c64.exe contrib_rt.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 contrib_rt.bas -o example.prg
 yape example.prg
 
 # Windows 
 ugbc.plus4.exe contrib_rt.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_rt.bas -o example.prg
 xplus4 example.prg
 
 # Windows 
 ugbc.plus4.exe contrib_rt.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_rt.bas -o example.bin
 xroar -rompath (your rom path) example.bin
 
 # Windows 
 ugbc.d32.exe contrib_rt.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_rt.bas -o example.bin
 xroar -rompath (your rom path) example.bin
 
 # Windows 
 ugbc.d64.exe contrib_rt.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_rt.bas -o example.k7
 dcmoto
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
 
 # Windows 
 ugbc.pc128op.exe contrib_rt.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_rt.bas -o example.k7
 dcmoto
 (choose BASIC 128)
 CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
 
 # Windows 
 ugbc.pc128op.exe contrib_rt.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_rt.bas -o example.prg
 xvic --memory 24k example.prg
 
 # Windows 
 ugbc.vic20.exe contrib_rt.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_rt.bas -o example.tap
 Speccy example.tap
 
 # Windows 
 ugbc.zx.exe contrib_rt.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_rt.bas -o example.rom
 openmsx -cart example.rom
 
 # Windows 
 ugbc.msx1.exe contrib_rt.bas -o example.rom
 openmsx -cart example.rom

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

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