From: uz Date: Fri, 30 Oct 2009 09:58:11 +0000 (+0000) Subject: Merged the sine/cosine routines into one file, because they're often used X-Git-Tag: V2.13.1~129 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=c65925b0b912f4b3665291e380a195d2b27d4fe8;p=cc65 Merged the sine/cosine routines into one file, because they're often used together, we save some code in this case, and the sine table isn't of real use for programs, because it contains some specialities. git-svn-id: svn://svn.cc65.org/cc65/trunk@4400 b7a2c559-68d2-44c3-8de9-860c34a00d81 --- diff --git a/libsrc/common/Makefile b/libsrc/common/Makefile index e912795f7..381742fdf 100644 --- a/libsrc/common/Makefile +++ b/libsrc/common/Makefile @@ -99,9 +99,7 @@ S_OBJS = _cwd.o \ atexit.o \ atoi.o \ calloc.o \ - cc65_cos.o \ - cc65_sin.o \ - cc65_sintab.o \ + cc65_sincos.o \ chdir.o \ copydata.o \ creat.o \ diff --git a/libsrc/common/cc65_cos.s b/libsrc/common/cc65_cos.s deleted file mode 100644 index 06a59af35..000000000 --- a/libsrc/common/cc65_cos.s +++ /dev/null @@ -1,48 +0,0 @@ -; -; Fixed point cosine function. -; -; Returns the cosine for the given argument as angular degree. -; Valid argument range is 0..360 -; -; -; Ullrich von Bassewitz, 2009-10-29 -; - - .export _cc65_cos - - .import _cc65_sin - - - -; --------------------------------------------------------------------------- -; - -.code - -.proc _cc65_cos - -; cos(x) = sin(x+90) - - clc - adc #90 - bcc L1 - inx - -; If x is now larger than 360, we need to subtract 360. - -L1: cpx #>360 - bne L2 - cmp #<360 -L2: bcc L4 - - sbc #<360 - bcs L3 - dex -L3: dex - -L4: jmp _cc65_sin - - -.endproc - - diff --git a/libsrc/common/cc65_sin.s b/libsrc/common/cc65_sin.s deleted file mode 100644 index 6d83086cf..000000000 --- a/libsrc/common/cc65_sin.s +++ /dev/null @@ -1,113 +0,0 @@ -; -; Fixed point sine function. -; -; Returns the cosine for the given argument as angular degree. -; Valid argument range is 0..360 -; -; -; Ullrich von Bassewitz, 2009-10-29 -; - - .export _cc65_sin - - .import _cc65_sintab - - -; --------------------------------------------------------------------------- -; - -.code - -.proc _cc65_sin - -; If the high byte is non zero, argument is > 255 - - cpx #0 - bne L3 - cmp #180 - bcs L4 - -; 0..179° - - cmp #90 - bcc L1 - -; 90..179°. Value is identical to sin(180-val). Carry is set on entry. -; -; 180-val := -val + 180. -; With -; -val := (val ^ $FF) + 1 -; we get -; 180-val = (val ^ $FF) + 1 + 180 -; Since carry is set, we can drop the "+ 1". -; - - eor #$FF - adc #180 ; 180-val - -; 0..89°. Values for 87..90° are actually 1.0. Since this format doesn't fit -; into the table, we have to check for it manually. - -L1: cmp #87 - bcc L2 - -; The value is 1.0 - - ldx #>(1 << 8) - lda #<(1 << 8) - rts - -; 0..86°. Read the value from the table. - -L2: tay - ldx #0 - lda _cc65_sintab,y - rts - -; 180..360°. sin(x) = -sin(x-180). Since the argument is in range 0..180 -; after the subtraction, we don't need to handle the high byte. - -L3: sec -L4: sbc #180 - - cmp #90 - bcc L5 - -; 270..360°. Value is identical to -sin(180-val). Carry is set on entry. -; -; 180-val := -val + 180. -; With -; -val := (val ^ $FF) + 1 -; we get -; 180-val = (val ^ $FF) + 1 + 180 -; Since carry is set, we can drop the "+ 1". -; - - eor #$FF - adc #180 ; 180-val - -; 180..269°. Values for 267..269° are actually -1.0. Since this format doesn't -; fit into the table, we have to check for it manually. - -L5: ldx #$FF - cmp #87 - bcc L6 - -; The value is -1.0 - - lda #<(-1 << 8) - rts - -; 180..266°. Read the value from the table. Carry is clear on entry. - -L6: tay - txa ; A = $FF - eor _cc65_sintab,y - adc #1 - bcc L7 - inx -L7: rts - -.endproc - - diff --git a/libsrc/common/cc65_sincos.s b/libsrc/common/cc65_sincos.s new file mode 100644 index 000000000..d0b108297 --- /dev/null +++ b/libsrc/common/cc65_sincos.s @@ -0,0 +1,161 @@ +; +; Fixed point cosine/sine functions. +; +; Returns the cosine/sine for the given argument as angular degree. +; Valid argument range is 0..360 for both functions. They will return +; garbage if the argument is not in a valid range. Result is in 8.8 fixed +; point format, so $100 is 1.0 and $FF00 is -1.0. +; +; +; Ullrich von Bassewitz, 2009-10-29 +; + + .export _cc65_cos, _cc65_sin + + +; --------------------------------------------------------------------------- +; Sinus table covering values from 0..86° as 0.8 fixed point values. Values +; for 87..90° are actually 1.0 (= $100), will therefore not fit in the table +; and are covered specially in the code below. + +.rodata + +_cc65_sintab: + .byte $00, $04, $09, $0D, $12, $16, $1B, $1F, $24, $28 + .byte $2C, $31, $35, $3A, $3E, $42, $47, $4B, $4F, $53 + .byte $58, $5C, $60, $64, $68, $6C, $70, $74, $78, $7C + .byte $80, $84, $88, $8B, $8F, $93, $96, $9A, $9E, $A1 + .byte $A5, $A8, $AB, $AF, $B2, $B5, $B8, $BB, $BE, $C1 + .byte $C4, $C7, $CA, $CC, $CF, $D2, $D4, $D7, $D9, $DB + .byte $DE, $E0, $E2, $E4, $E6, $E8, $EA, $EC, $ED, $EF + .byte $F1, $F2, $F3, $F5, $F6, $F7, $F8, $F9, $FA, $FB + .byte $FC, $FD, $FE, $FE, $FF, $FF, $FF + + + +; --------------------------------------------------------------------------- +; Cosine function. Is actually implemented as cos(x) = sin(x+90) + +.code + +_cc65_cos: + +; cos(x) = sin(x+90) + + clc + adc #90 + bcc @L1 + inx + +; If x is now larger than 360, we need to subtract 360. + +@L1: cpx #>360 + bne @L2 + cmp #<360 +@L2: bcc _cc65_sin + + sbc #<360 + bcs @L3 + dex +@L3: dex + +; --------------------------------------------------------------------------- +; Sine function. Uses +; +; table lookup for 0..89° +; sin(x) = sin(180-x) for 90°..179° +; sin(x) = -sin(x-180) for 180..360° +; +; Plus special handling for the values missing in the table. + +_cc65_sin: + +; If the high byte is non zero, argument is > 255 + + cpx #0 + bne L3 + cmp #180 + bcs L4 + +; 0..179° + + cmp #90 + bcc L1 + +; 90..179°. Value is identical to sin(180-val). Carry is set on entry. +; +; 180-val := -val + 180. +; With +; -val := (val ^ $FF) + 1 +; we get +; 180-val = (val ^ $FF) + 1 + 180 +; Since carry is set, we can drop the "+ 1". +; + + eor #$FF + adc #180 ; 180-val + +; 0..89°. Values for 87..90° are actually 1.0. Since this format doesn't fit +; into the table, we have to check for it manually. + +L1: cmp #87 + bcc L2 + +; The value is 1.0 + + ldx #>(1 << 8) + lda #<(1 << 8) + rts + +; 0..86°. Read the value from the table. + +L2: tay + ldx #0 + lda _cc65_sintab,y + rts + +; 180..360°. sin(x) = -sin(x-180). Since the argument is in range 0..180 +; after the subtraction, we don't need to handle the high byte. + +L3: sec +L4: sbc #180 + + cmp #90 + bcc L5 + +; 270..360°. Value is identical to -sin(180-val). Carry is set on entry. +; +; 180-val := -val + 180. +; With +; -val := (val ^ $FF) + 1 +; we get +; 180-val = (val ^ $FF) + 1 + 180 +; Since carry is set, we can drop the "+ 1". +; + + eor #$FF + adc #180 ; 180-val + +; 180..269°. Values for 267..269° are actually -1.0. Since this format doesn't +; fit into the table, we have to check for it manually. + +L5: ldx #$FF + cmp #87 + bcc L6 + +; The value is -1.0 + + lda #<(-1 << 8) + rts + +; 180..266°. Read the value from the table. Carry is clear on entry. + +L6: tay + txa ; A = $FF + eor _cc65_sintab,y + adc #1 + bcc L7 + inx +L7: rts + + diff --git a/libsrc/common/cc65_sintab.s b/libsrc/common/cc65_sintab.s deleted file mode 100644 index 88464817a..000000000 --- a/libsrc/common/cc65_sintab.s +++ /dev/null @@ -1,24 +0,0 @@ -; -; Sinus table -; -; Ullrich von Bassewitz, 2009-10-29 -; - - .export _cc65_sintab - - -; --------------------------------------------------------------------------- -; - -.rodata - -_cc65_sintab: - .byte $00, $04, $09, $0D, $12, $16, $1B, $1F, $24, $28 - .byte $2C, $31, $35, $3A, $3E, $42, $47, $4B, $4F, $53 - .byte $58, $5C, $60, $64, $68, $6C, $70, $74, $78, $7C - .byte $80, $84, $88, $8B, $8F, $93, $96, $9A, $9E, $A1 - .byte $A5, $A8, $AB, $AF, $B2, $B5, $B8, $BB, $BE, $C1 - .byte $C4, $C7, $CA, $CC, $CF, $D2, $D4, $D7, $D9, $DB - .byte $DE, $E0, $E2, $E4, $E6, $E8, $EA, $EC, $ED, $EF - .byte $F1, $F2, $F3, $F5, $F6, $F7, $F8, $F9, $FA, $FB - .byte $FC, $FD, $FE, $FE, $FF, $FF, $FF