Rotating 3D Earth (Elk/Beeb)

[0xC0DE]

Demonstration of fake spherical image mapping.
Cross-platform demo. Runs on Acorn Electron and BBC Micro, Master 128. PAGE needs to be &E00 though!
SPACE toggles between raster version and solid version.
Real time calculation (using lookup tables obviously), not some animation frames read from disk

earth3d.ssd

(10.25 KiB) Downloaded 143 times

[oss003]

Nice demo .... looks great ......

Greetings
Kees

[0xC0DE]

Nice demo .... looks great ......

Thanks Kees!

[tricky]

Nice, now for MODE 0 with dither

[0xC0DE]

Nice, now for MODE 0 with dither

Hold my beer!

[pdjstone]

Trying to run this in JSBeeb - I set PAGE to &E00 but I still get the message about setting PAGE. What am I doing wrong?

[0xC0DE]

Trying to run this in JSBeeb - I set PAGE to &E00 but I still get the message about setting PAGE. What am I doing wrong?

DFS is in the way on a regular BBC Micro. Altering PAGE manually won't change that.
Try BBC Master 128 mode of jsbeeb: https://bbc.godbolt.org/?&model=Master

[marcusjambler]

Like it

[0xC0DE]

Like it

[pdjstone]

DFS is in the way on a regular BBC Micro. Altering PAGE manually won't change that.
Try BBC Master 128 mode of jsbeeb: https://bbc.godbolt.org/?&model=Master

Thanks that works! Out of interest how would you get it running on a Model B? I there a way to load it into memory, disable DFS and then run?

[0xC0DE]

DFS is in the way on a regular BBC Micro. Altering PAGE manually won't change that.
Try BBC Master 128 mode of jsbeeb: https://bbc.godbolt.org/?&model=Master

Thanks that works! Out of interest how would you get it running on a Model B? I there a way to load it into memory, disable DFS and then run?

Yes, that is one possibility (but I was lazy for this version ). The other option is to use a DFS ROM that keeps PAGE at &E00.

[jgharston]

DFS is in the way on a regular BBC Micro. Altering PAGE manually won't change that.
Try BBC Master 128 mode of jsbeeb: https://bbc.godbolt.org/?&model=Master

Thanks that works! Out of interest how would you get it running on a Model B? I there a way to load it into memory, disable DFS and then run?

!BOOT:

Code: Select all

*BASIC
MODE 7:*LOAD 0xC0DE 5000
OS."TAPE":OS."FX143,12,255":F.A%=0TO&25FFS.4:A%!&E00=A%!&5000:N.:MO.2:MO.5:V.23,1,0;0;0;0;19,1,4;0;19,3,7;0;12,21:CALL &E00

[0xC0DE]

DFS is in the way on a regular BBC Micro. Altering PAGE manually won't change that.
Try BBC Master 128 mode of jsbeeb: https://bbc.godbolt.org/?&model=Master

Thanks that works! Out of interest how would you get it running on a Model B? I there a way to load it into memory, disable DFS and then run?

!BOOT:

Code: Select all

*BASIC
MODE 7:*LOAD 0xC0DE 5000
OS."TAPE":OS."FX143,12,255":F.A%=0TO&25FFS.4:A%!&E00=A%!&5000:N.:MO.2:MO.5:V.23,1,0;0;0;0;19,1,4;0;19,3,7;0;12,21:CALL &E00

Well, somebody wasn't lazy like I was, thanks!

[jgharston]

!BOOT:

Code: Select all

*BASIC
MODE 7:*LOAD 0xC0DE 5000
OS."TAPE":OS."FX143,12,255":F.A%=0TO&25FFS.4:A%!&E00=A%!&5000:N.:MO.2:MO.5:V.23,1,0;0;0;0;19,1,4;0;19,3,7;0;12,21:CALL &E00

Well, somebody wasn't lazy like I was, thanks!

Could even put it in the code.
Set load address=FFFF5000
Set exec address=FFFF7628 (whatever L7628 turns out to be)
Append:
.L7600
.loop2
LDA vdu,Y:JSR OSWRCH
INY:CPY #L7628-vdu:BNE loop2
JMP &E00
.vdu
EQUS CHR$22+CHR$2+CHR$22+CHR$5
EQUS CHR$23+CHR$1+STRING$(8,CHR$0)
EQUS CHR$19+CHR$1+CHR$4+STRING$(3,CHR$0)
EQUS CHR$19+CHR$3+CHR$7+STRING$(3,CHR$0)
.L7628 :\ check this
LDA #140:JSR OSBYTE :\ Select tape
LDA #143:LDX #12:LDY #255:JSR OSBYTE :\ Turn off NMIs
LDY #0:STY &70:STY &72 :\ Copy from 5000 -> 0E00
LDA #&50:STA &71
LDA #&0E:STA &73
.loop1
LDA (&70),Y:STA (&72),Y:INY:BNE loop1
INC &71:INC &73
LDA &73:CMP #&76:BNE loop1
JMP &3400

...except my arithmetic tells me the code lives at &E00-&3400, and the MODE 2 will overwrite the code at &3000-&3400.