chrisly42/PretrackerRaspberryCasket
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Replaced the period table by byte-deltas, saved 36 bytes and compression is even better!

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Chris Hodges 2023-08-10 20:27:30 +02:00
parent 40822e295c
commit dd8c224199
4 changed files with 32 additions and 28 deletions
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7
README.md
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@ -1,7 +1,7 @@
# Raspberry Casket
A fast and small open source Pretracker replayer
## Raspberry Casket Player V2.x (26-Jul-2023)
## Raspberry Casket Player V2.x (10-Aug-2023)
Provided by Chris 'platon42' Hodges <chrisly@platon42.de>
@ -90,7 +90,7 @@ The original code compressed with *Blueberry's* Shrinkler goes from
18052 bytes down to 9023 bytes.
Raspberry Casket, depending on the features compiled in, is about
5992 bytes and goes down to ~4238 bytes (in isolation).
5942 bytes and goes down to ~4202 bytes (in isolation).
So this means that the optimization is not just "on the outside".
@ -144,8 +144,9 @@ solve this problem.
- Split wave generation out of main file, reorganised content into header files.
- Optimized some more code paths for Raspberry Casket replayer.
- In the wave generator optimized away a table (32 words), replacement code is even smaller!
- Replaced the period table by byte-deltas, saved 36 bytes and compression is even better!
- Added Presto player draft.
- Drop-in replacement code size: 5992 bytes.
- Drop-in replacement code size: 5942 bytes.
### V1.x (unreleased)
- Fixed a bug regarding the copper output mode with looping waves having a loop-offset.

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binaries/raspberry_casket.bin
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52
src/raspberry_casket.asm
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@ -1,5 +1,5 @@
;--------------------------------------------------------------------
; Raspberry Casket Player V2.x (26-Jul-2023)
; Raspberry Casket Player V2.x (10-Aug-2023)
; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
;
; Provided by Chris 'platon42' Hodges <chrisly@platon42.de>
@ -87,7 +87,7 @@
; 18052 bytes down to 9023 bytes.
;
; Raspberry Casket, depending on the features compiled in, is about
; 5992 bytes and goes down to ~4238 bytes (in isolation).
; 5942 bytes and goes down to ~4202 bytes (in isolation).
;
; So this means that the optimization is not just "on the outside".
;
@ -162,7 +162,11 @@ PRETRACKER_PARANOIA_MODE = 0
; I guess this might add some phasing to the sound (which would be
; only audible in a mono mix, I would think), but it comes with an
; extra multiplication per channel.
; If you really want that, enable this switch.
; Moreover, I traced down that this may reduce the Amiga period
; value lower than the minimum allowed value of 124. This may cause
; distortions (like playing a note in Protracker with pitch B-3)
; on the delayed track.
; If you really want (to risk) that, enable this switch.
IFND PRETRACKER_DUBIOUS_PITCH_SHIFT_FOR_DELAYED_TRACK
PRETRACKER_DUBIOUS_PITCH_SHIFT_FOR_DELAYED_TRACK = 0
ENDC
@ -590,28 +594,28 @@ pre_PlayerInit:
; ----------------------------------------
lea pre_period_table(pc),a0
lea pre_delta_period_table(pc),a0
lea pv_period_table(a4),a1
.calcperiodtable
; fill the missing entries in the period table by interpolating
move.w (a0)+,d2
moveq.l #3*NOTES_IN_OCTAVE-1,d7
.periodtableloop
move.w (a0)+,d0
move.w (a0),d1
sub.w d0,d1
swap d0
clr.w d0
moveq.l #0,d0
moveq.l #0,d1
move.b (a0)+,d1
move.w d2,d0
sub.w d1,d2
swap d1
clr.w d1
asr.l #4,d1
lsr.l #4,d1
moveq.l #16-1,d6
.perfineipolloop
swap d0
move.w d0,(a1)+
swap d0
add.l d1,d0
sub.l d1,d0
swap d0
dbra d6,.perfineipolloop
dbra d7,.periodtableloop
@ -791,7 +795,7 @@ pre_PlayerTick:
move.l d1,(a1)+ ; pcd_pat_vol_ramp_speed_b, pcd_pat_2nd_inst_num4_b, pcd_pat_2nd_inst_delay_b, pcd_wave_offset_b
move.l d1,(a1)+ ; pcd_inst_pitch_slide_w and pcd_inst_sel_arp_note_w
move.w d1,(a1)+ ; pcd_inst_note_pitch_w
addq.w #2,a1
addq.l #2,a1
move.l d1,(a1)+ ; pcd_inst_line_ticks_b, pcd_inst_pitch_pinned_b, pcd_inst_vol_slide_b, pcd_inst_step_pos_b
@ -2024,14 +2028,14 @@ pre_PlayerTick:
bra.s .loop_handling_done
.wave_has_no_subloop
moveq.l #0,d1
move.b pcd_wave_offset_b(a5),d1
beq.s .loop_handling_done
tst.b wi_allow_9xx_b(a3)
beq.s .loop_handling_done
; apply offset from pattern for sample without subloop
lsl.w #8,d1 ; clear upper byte
lsr.w #1,d1
lsl.w #7,d1
clr.b pcd_wave_offset_b(a5)
@ -2491,7 +2495,7 @@ pre_PlayerTick:
rts
;--------------------------------------------------------------------
; table data currently about 594 bytes
; table data currently about 496 bytes
; Tables used by WaveGen
pre_roll_off_table: ; used by WaveGen
dc.w $400,$200,$180,$140,$100,$C0,$A0,$80,$78,$74,$6E
@ -2510,7 +2514,7 @@ pre_log12_table:
pre_modulator_ramp_8: ; used by WaveGen
;dc.w 77,293,539,1079,1337,1877,2431,3031 ; the 1079 value is strange (938 better?)
dc.w $4D,$125,$21B,$437,$539,$755,$96D,$BD7
dc.w $4D,$125,$21B,$437,$539,$755,$96D,$BD7
; linear then steep quadratic slope
pre_vib_speed_table:
@ -2566,11 +2570,11 @@ pre_octave_select_table:
IFNE PRETRACKER_DUBIOUS_PITCH_SHIFT_FOR_DELAYED_TRACK
; -4,-3,-1,1,2,3,4,0
pre_minus4plus4_table:
dc.b $FC,$FB,$FF,1,2,3,4,0
dc.b $FC,$FB,$FF,1,2,3,4,0
ENDC
pre_period_table:
dc.w $350,$320,$2F2,$2C8,$2A0,$279,$256,$236,$216,$1F8,$1DC,$1C0
dc.w $1A8,$190,$179,$164,$151,$13E,$12C,$11B,$10B,$FC,$EE,$E0
dc.w $D4,$C8,$BD,$B2,$A8,$9F,$96,$8D,$86,$7E,$78,$71
dc.w $71
pre_delta_period_table:
dc.w $350
dc.b $30,$2e,$2a,$28,$27,$23,$20,$20,$1e,$1c,$1c,$18,$18,$17,$15,$13
dc.b $13,$12,$11,$10,$0f,$0e,$0e,$0c,$0c,$0b,$0b,$0a,$09,$09,$09,$07
dc.b $08,$06,$07,$00

1
src/raspberry_casket.i
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@ -61,7 +61,6 @@
; - 6 Bits : Pitch ($01 is C-0)
; - 4 Bits : unused?
; - 12 Bits: Effect
; - Patterns x steps x 3 bytes
;
; Wave definitions (WAVE):
; - 24 (!) x Null terminated string (or 23 chars max)