Home » Archimedes archive » Acorn User » AU 1997-05 B.adf » Regulars » StarInfo/clouds/Brown/s/mapfn
StarInfo/clouds/Brown/s/mapfn
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Archimedes archive » Acorn User » AU 1997-05 B.adf » Regulars |
| Filename: | StarInfo/clouds/Brown/s/mapfn |
| Read OK: | ✔ |
| File size: | 088C bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
AREA |data$$dataarea|, DATA
diffx DCD 0
diffz DCD 0
divtab DCD 0
GBLA fill
fill SETA 1
WHILE fill<1322
DCD 786432000/fill
fill SETA fill+1
WEND
AREA |code$$codearea|, CODE, READONLY
EXPORT copy
; r0 source pointer
; r1 destination pointer
copy
stmfd r13!,{r2-r12,r14}
mov r2,#256
yloop
mov r3,r0
mov r5,#256
xloop
ldr r4,[r3],#4
str r4,[r1],#4
subs r5,r5,#4
bgt xloop
add r0,r0,#320
subs r2,r2,#1
bgt yloop
ldmfd r13!,{r2-r12,pc}
EXPORT maptoceil
; entry* r0 - screenbase
; r1 - srcbase
; r2 - divtab
; r3 - sin
; r4 - cos
; r5 - diff x
; r6 - diff z
maptoceil
stmfd r13!,{r0-r12,r14}
ldmia r0,{r0-r6} ; load a chunk of parameters
adrl r2,divtab
adrl r7,diffx
stmia r7,{r5,r6}
mov r5,#1020 ; y2
yloop2
add r7,r5,#300
ldr r7,[r2,r7,lsl #2]
sub r7,r7,#589824 ; z
mov r8,#640
add r9,r7,#589824
mul r8,r9,r8
mov r8,r8,asr #10 ; x
mul r9,r8,r4
mla r11,r7,r3,r9 ; x3
mul r10,r4,r7
mul r8,r3,r8
sub r10,r10,r8 ; z3
; z (r7) intact from before
mov r8,#636 ; moved along a bit...
add r9,r7,#589824
mul r8,r9,r8
mov r8,r8,asr #10 ; x
mul r9,r8,r4
mla r9,r7,r3,r9 ; x3
mul r7,r4,r7
mul r8,r3,r8
sub r7,r7,r8 ; z3
; line goes from (r11,r10) to (r9,r7)
sub r7,r7,r10 ; make difference z
sub r9,r9,r11 ; x
adrl r8,diffx ; move around viewpoint a bit
ldmia r8,{r8,r12}
add r11,r11,r8,asl #22
add r10,r10,r12,asl #22
stmfd r13!,{r4}
mov r6,#320
xloop2
mov r12,r11,lsr #24
mov r8,r10,lsr #24
add r8,r8,r12,lsl #8
ldrb r4,[r1,r8]
add r11,r11,r9
add r10,r10,r7
mov r12,r11,lsr #24
mov r8,r10,lsr #24
add r8,r8,r12,lsl #8
ldrb r8,[r1,r8]
orr r4,r4,r8,lsl #8
add r11,r11,r9
add r10,r10,r7
mov r12,r11,lsr #24
mov r8,r10,lsr #24
add r8,r8,r12,lsl #8
ldrb r8,[r1,r8]
orr r4,r4,r8,lsl #16
add r11,r11,r9
add r10,r10,r7
mov r12,r11,lsr #24
mov r8,r10,lsr #24
add r8,r8,r12,lsl #8
ldrb r8,[r1,r8]
orr r4,r4,r8,lsl #24
add r11,r11,r9
add r10,r10,r7
str r4,[r0],#4
subs r6,r6,#4
bgt xloop2
ldmfd r13!,{r4}
subs r5,r5,#4
bge yloop2
ldmfd r13!,{r0-r12,pc}
END
00000000 0a 09 41 52 45 41 20 7c 64 61 74 61 24 24 64 61 |..AREA |data$$da|
00000010 74 61 61 72 65 61 7c 2c 20 44 41 54 41 0a 0a 64 |taarea|, DATA..d|
00000020 69 66 66 78 09 44 43 44 09 30 0a 64 69 66 66 7a |iffx.DCD.0.diffz|
00000030 09 44 43 44 09 30 0a 0a 64 69 76 74 61 62 09 44 |.DCD.0..divtab.D|
00000040 43 44 09 30 0a 09 47 42 4c 41 09 66 69 6c 6c 0a |CD.0..GBLA.fill.|
00000050 66 69 6c 6c 09 53 45 54 41 09 31 0a 09 57 48 49 |fill.SETA.1..WHI|
00000060 4c 45 09 66 69 6c 6c 3c 31 33 32 32 0a 09 44 43 |LE.fill<1322..DC|
00000070 44 09 37 38 36 34 33 32 30 30 30 2f 66 69 6c 6c |D.786432000/fill|
00000080 0a 66 69 6c 6c 09 53 45 54 41 09 66 69 6c 6c 2b |.fill.SETA.fill+|
00000090 31 0a 09 57 45 4e 44 0a 0a 0a 09 41 52 45 41 20 |1..WEND....AREA |
000000a0 7c 63 6f 64 65 24 24 63 6f 64 65 61 72 65 61 7c ||code$$codearea||
000000b0 2c 20 43 4f 44 45 2c 20 52 45 41 44 4f 4e 4c 59 |, CODE, READONLY|
000000c0 0a 0a 09 45 58 50 4f 52 54 20 63 6f 70 79 0a 0a |...EXPORT copy..|
000000d0 3b 20 72 30 20 73 6f 75 72 63 65 20 70 6f 69 6e |; r0 source poin|
000000e0 74 65 72 0a 3b 20 72 31 20 64 65 73 74 69 6e 61 |ter.; r1 destina|
000000f0 74 69 6f 6e 20 70 6f 69 6e 74 65 72 0a 63 6f 70 |tion pointer.cop|
00000100 79 0a 09 73 74 6d 66 64 20 72 31 33 21 2c 7b 72 |y..stmfd r13!,{r|
00000110 32 2d 72 31 32 2c 72 31 34 7d 0a 09 6d 6f 76 20 |2-r12,r14}..mov |
00000120 72 32 2c 23 32 35 36 0a 79 6c 6f 6f 70 0a 09 6d |r2,#256.yloop..m|
00000130 6f 76 20 72 33 2c 72 30 0a 09 6d 6f 76 20 72 35 |ov r3,r0..mov r5|
00000140 2c 23 32 35 36 0a 78 6c 6f 6f 70 0a 09 6c 64 72 |,#256.xloop..ldr|
00000150 20 72 34 2c 5b 72 33 5d 2c 23 34 0a 09 73 74 72 | r4,[r3],#4..str|
00000160 20 72 34 2c 5b 72 31 5d 2c 23 34 0a 09 73 75 62 | r4,[r1],#4..sub|
00000170 73 20 72 35 2c 72 35 2c 23 34 0a 09 62 67 74 20 |s r5,r5,#4..bgt |
00000180 78 6c 6f 6f 70 0a 09 61 64 64 20 72 30 2c 72 30 |xloop..add r0,r0|
00000190 2c 23 33 32 30 0a 09 73 75 62 73 20 72 32 2c 72 |,#320..subs r2,r|
000001a0 32 2c 23 31 0a 09 62 67 74 20 79 6c 6f 6f 70 0a |2,#1..bgt yloop.|
000001b0 09 6c 64 6d 66 64 20 72 31 33 21 2c 7b 72 32 2d |.ldmfd r13!,{r2-|
000001c0 72 31 32 2c 70 63 7d 0a 0a 0a 0a 09 45 58 50 4f |r12,pc}.....EXPO|
000001d0 52 54 20 6d 61 70 74 6f 63 65 69 6c 0a 0a 3b 20 |RT maptoceil..; |
000001e0 65 6e 74 72 79 2a 20 72 30 20 2d 20 73 63 72 65 |entry* r0 - scre|
000001f0 65 6e 62 61 73 65 0a 3b 20 20 20 20 20 20 20 20 |enbase.; |
00000200 72 31 20 2d 20 73 72 63 62 61 73 65 0a 3b 20 20 |r1 - srcbase.; |
00000210 20 20 20 20 20 20 72 32 20 2d 20 64 69 76 74 61 | r2 - divta|
00000220 62 0a 3b 20 20 20 20 20 20 20 20 72 33 20 2d 20 |b.; r3 - |
00000230 73 69 6e 0a 3b 20 20 20 20 20 20 20 20 72 34 20 |sin.; r4 |
00000240 2d 20 63 6f 73 0a 3b 20 20 20 20 20 20 20 20 72 |- cos.; r|
00000250 35 20 2d 20 64 69 66 66 20 78 0a 3b 20 20 20 20 |5 - diff x.; |
00000260 20 20 20 20 72 36 20 2d 20 64 69 66 66 20 7a 0a | r6 - diff z.|
00000270 6d 61 70 74 6f 63 65 69 6c 0a 09 73 74 6d 66 64 |maptoceil..stmfd|
00000280 20 72 31 33 21 2c 7b 72 30 2d 72 31 32 2c 72 31 | r13!,{r0-r12,r1|
00000290 34 7d 0a 0a 09 6c 64 6d 69 61 20 72 30 2c 7b 72 |4}...ldmia r0,{r|
000002a0 30 2d 72 36 7d 20 20 20 3b 20 6c 6f 61 64 20 61 |0-r6} ; load a|
000002b0 20 63 68 75 6e 6b 20 6f 66 20 70 61 72 61 6d 65 | chunk of parame|
000002c0 74 65 72 73 0a 0a 09 61 64 72 6c 20 72 32 2c 64 |ters...adrl r2,d|
000002d0 69 76 74 61 62 0a 0a 09 61 64 72 6c 20 72 37 2c |ivtab...adrl r7,|
000002e0 64 69 66 66 78 0a 09 73 74 6d 69 61 20 72 37 2c |diffx..stmia r7,|
000002f0 7b 72 35 2c 72 36 7d 0a 0a 09 6d 6f 76 20 72 35 |{r5,r6}...mov r5|
00000300 2c 23 31 30 32 30 20 20 20 20 20 20 3b 20 79 32 |,#1020 ; y2|
00000310 0a 0a 79 6c 6f 6f 70 32 0a 09 61 64 64 20 72 37 |..yloop2..add r7|
00000320 2c 72 35 2c 23 33 30 30 0a 09 6c 64 72 20 72 37 |,r5,#300..ldr r7|
00000330 2c 5b 72 32 2c 72 37 2c 6c 73 6c 20 23 32 5d 0a |,[r2,r7,lsl #2].|
00000340 09 73 75 62 20 72 37 2c 72 37 2c 23 35 38 39 38 |.sub r7,r7,#5898|
00000350 32 34 20 20 3b 20 7a 0a 0a 09 6d 6f 76 20 72 38 |24 ; z...mov r8|
00000360 2c 23 36 34 30 0a 09 61 64 64 20 72 39 2c 72 37 |,#640..add r9,r7|
00000370 2c 23 35 38 39 38 32 34 0a 09 6d 75 6c 20 72 38 |,#589824..mul r8|
00000380 2c 72 39 2c 72 38 0a 09 6d 6f 76 20 72 38 2c 72 |,r9,r8..mov r8,r|
00000390 38 2c 61 73 72 20 23 31 30 20 3b 20 78 0a 0a 09 |8,asr #10 ; x...|
000003a0 6d 75 6c 20 72 39 2c 72 38 2c 72 34 0a 09 6d 6c |mul r9,r8,r4..ml|
000003b0 61 20 72 31 31 2c 72 37 2c 72 33 2c 72 39 20 20 |a r11,r7,r3,r9 |
000003c0 20 3b 20 78 33 0a 09 6d 75 6c 20 72 31 30 2c 72 | ; x3..mul r10,r|
000003d0 34 2c 72 37 0a 09 6d 75 6c 20 72 38 2c 72 33 2c |4,r7..mul r8,r3,|
000003e0 72 38 0a 09 73 75 62 20 72 31 30 2c 72 31 30 2c |r8..sub r10,r10,|
000003f0 72 38 20 20 20 20 20 3b 20 7a 33 0a 0a 0a 09 20 |r8 ; z3.... |
00000400 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
00000410 20 20 3b 20 7a 20 28 72 37 29 20 69 6e 74 61 63 | ; z (r7) intac|
00000420 74 20 66 72 6f 6d 20 62 65 66 6f 72 65 0a 0a 09 |t from before...|
00000430 6d 6f 76 20 72 38 2c 23 36 33 36 20 20 20 20 20 |mov r8,#636 |
00000440 20 20 3b 20 6d 6f 76 65 64 20 61 6c 6f 6e 67 20 | ; moved along |
00000450 61 20 62 69 74 2e 2e 2e 0a 09 61 64 64 20 72 39 |a bit.....add r9|
00000460 2c 72 37 2c 23 35 38 39 38 32 34 0a 09 6d 75 6c |,r7,#589824..mul|
00000470 20 72 38 2c 72 39 2c 72 38 0a 09 6d 6f 76 20 72 | r8,r9,r8..mov r|
00000480 38 2c 72 38 2c 61 73 72 20 23 31 30 20 3b 20 78 |8,r8,asr #10 ; x|
00000490 0a 0a 09 6d 75 6c 20 72 39 2c 72 38 2c 72 34 0a |...mul r9,r8,r4.|
000004a0 09 6d 6c 61 20 72 39 2c 72 37 2c 72 33 2c 72 39 |.mla r9,r7,r3,r9|
000004b0 20 20 20 3b 20 78 33 0a 09 6d 75 6c 20 72 37 2c | ; x3..mul r7,|
000004c0 72 34 2c 72 37 0a 09 6d 75 6c 20 72 38 2c 72 33 |r4,r7..mul r8,r3|
000004d0 2c 72 38 0a 09 73 75 62 20 72 37 2c 72 37 2c 72 |,r8..sub r7,r7,r|
000004e0 38 20 20 20 20 20 20 3b 20 7a 33 0a 0a 09 3b 20 |8 ; z3...; |
000004f0 6c 69 6e 65 20 67 6f 65 73 20 66 72 6f 6d 20 28 |line goes from (|
00000500 72 31 31 2c 72 31 30 29 20 74 6f 20 28 72 39 2c |r11,r10) to (r9,|
00000510 72 37 29 0a 0a 09 73 75 62 20 72 37 2c 72 37 2c |r7)...sub r7,r7,|
00000520 72 31 30 20 20 20 20 20 3b 20 6d 61 6b 65 20 64 |r10 ; make d|
00000530 69 66 66 65 72 65 6e 63 65 20 20 7a 0a 09 73 75 |ifference z..su|
00000540 62 20 72 39 2c 72 39 2c 72 31 31 20 20 20 20 20 |b r9,r9,r11 |
00000550 3b 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |; |
00000560 20 20 20 78 0a 0a 09 61 64 72 6c 20 72 38 2c 64 | x...adrl r8,d|
00000570 69 66 66 78 20 20 20 20 20 3b 20 6d 6f 76 65 20 |iffx ; move |
00000580 61 72 6f 75 6e 64 20 76 69 65 77 70 6f 69 6e 74 |around viewpoint|
00000590 20 61 20 62 69 74 0a 09 6c 64 6d 69 61 20 72 38 | a bit..ldmia r8|
000005a0 2c 7b 72 38 2c 72 31 32 7d 0a 09 61 64 64 20 72 |,{r8,r12}..add r|
000005b0 31 31 2c 72 31 31 2c 72 38 2c 61 73 6c 20 23 32 |11,r11,r8,asl #2|
000005c0 32 0a 09 61 64 64 20 72 31 30 2c 72 31 30 2c 72 |2..add r10,r10,r|
000005d0 31 32 2c 61 73 6c 20 23 32 32 0a 0a 09 73 74 6d |12,asl #22...stm|
000005e0 66 64 20 72 31 33 21 2c 7b 72 34 7d 0a 0a 09 6d |fd r13!,{r4}...m|
000005f0 6f 76 20 72 36 2c 23 33 32 30 0a 0a 78 6c 6f 6f |ov r6,#320..xloo|
00000600 70 32 0a 09 6d 6f 76 20 72 31 32 2c 72 31 31 2c |p2..mov r12,r11,|
00000610 6c 73 72 20 23 32 34 0a 09 6d 6f 76 20 72 38 2c |lsr #24..mov r8,|
00000620 72 31 30 2c 6c 73 72 20 23 32 34 0a 09 61 64 64 |r10,lsr #24..add|
00000630 20 72 38 2c 72 38 2c 72 31 32 2c 6c 73 6c 20 23 | r8,r8,r12,lsl #|
00000640 38 0a 0a 09 6c 64 72 62 20 72 34 2c 5b 72 31 2c |8...ldrb r4,[r1,|
00000650 72 38 5d 0a 0a 09 61 64 64 20 72 31 31 2c 72 31 |r8]...add r11,r1|
00000660 31 2c 72 39 0a 09 61 64 64 20 72 31 30 2c 72 31 |1,r9..add r10,r1|
00000670 30 2c 72 37 0a 0a 0a 09 6d 6f 76 20 72 31 32 2c |0,r7....mov r12,|
00000680 72 31 31 2c 6c 73 72 20 23 32 34 0a 09 6d 6f 76 |r11,lsr #24..mov|
00000690 20 72 38 2c 72 31 30 2c 6c 73 72 20 23 32 34 0a | r8,r10,lsr #24.|
000006a0 09 61 64 64 20 72 38 2c 72 38 2c 72 31 32 2c 6c |.add r8,r8,r12,l|
000006b0 73 6c 20 23 38 0a 0a 09 6c 64 72 62 20 72 38 2c |sl #8...ldrb r8,|
000006c0 5b 72 31 2c 72 38 5d 0a 09 6f 72 72 20 72 34 2c |[r1,r8]..orr r4,|
000006d0 72 34 2c 72 38 2c 6c 73 6c 20 23 38 0a 0a 09 61 |r4,r8,lsl #8...a|
000006e0 64 64 20 72 31 31 2c 72 31 31 2c 72 39 0a 09 61 |dd r11,r11,r9..a|
000006f0 64 64 20 72 31 30 2c 72 31 30 2c 72 37 0a 0a 0a |dd r10,r10,r7...|
00000700 09 6d 6f 76 20 72 31 32 2c 72 31 31 2c 6c 73 72 |.mov r12,r11,lsr|
00000710 20 23 32 34 0a 09 6d 6f 76 20 72 38 2c 72 31 30 | #24..mov r8,r10|
00000720 2c 6c 73 72 20 23 32 34 0a 09 61 64 64 20 72 38 |,lsr #24..add r8|
00000730 2c 72 38 2c 72 31 32 2c 6c 73 6c 20 23 38 0a 0a |,r8,r12,lsl #8..|
00000740 09 6c 64 72 62 20 72 38 2c 5b 72 31 2c 72 38 5d |.ldrb r8,[r1,r8]|
00000750 0a 09 6f 72 72 20 72 34 2c 72 34 2c 72 38 2c 6c |..orr r4,r4,r8,l|
00000760 73 6c 20 23 31 36 0a 0a 09 61 64 64 20 72 31 31 |sl #16...add r11|
00000770 2c 72 31 31 2c 72 39 0a 09 61 64 64 20 72 31 30 |,r11,r9..add r10|
00000780 2c 72 31 30 2c 72 37 0a 0a 0a 09 6d 6f 76 20 72 |,r10,r7....mov r|
00000790 31 32 2c 72 31 31 2c 6c 73 72 20 23 32 34 0a 09 |12,r11,lsr #24..|
000007a0 6d 6f 76 20 72 38 2c 72 31 30 2c 6c 73 72 20 23 |mov r8,r10,lsr #|
000007b0 32 34 0a 09 61 64 64 20 72 38 2c 72 38 2c 72 31 |24..add r8,r8,r1|
000007c0 32 2c 6c 73 6c 20 23 38 0a 0a 09 6c 64 72 62 20 |2,lsl #8...ldrb |
000007d0 72 38 2c 5b 72 31 2c 72 38 5d 0a 09 6f 72 72 20 |r8,[r1,r8]..orr |
000007e0 72 34 2c 72 34 2c 72 38 2c 6c 73 6c 20 23 32 34 |r4,r4,r8,lsl #24|
000007f0 0a 0a 09 61 64 64 20 72 31 31 2c 72 31 31 2c 72 |...add r11,r11,r|
00000800 39 0a 09 61 64 64 20 72 31 30 2c 72 31 30 2c 72 |9..add r10,r10,r|
00000810 37 0a 0a 09 73 74 72 20 72 34 2c 5b 72 30 5d 2c |7...str r4,[r0],|
00000820 23 34 0a 0a 09 73 75 62 73 20 72 36 2c 72 36 2c |#4...subs r6,r6,|
00000830 23 34 0a 09 62 67 74 20 78 6c 6f 6f 70 32 0a 0a |#4..bgt xloop2..|
00000840 09 6c 64 6d 66 64 20 72 31 33 21 2c 7b 72 34 7d |.ldmfd r13!,{r4}|
00000850 0a 0a 09 73 75 62 73 20 72 35 2c 72 35 2c 23 34 |...subs r5,r5,#4|
00000860 0a 09 62 67 65 20 79 6c 6f 6f 70 32 0a 0a 09 6c |..bge yloop2...l|
00000870 64 6d 66 64 20 72 31 33 21 2c 7b 72 30 2d 72 31 |dmfd r13!,{r0-r1|
00000880 32 2c 70 63 7d 0a 0a 09 45 4e 44 0a |2,pc}...END.|
0000088c 
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