the Furnace file format (.fur)

while Furnace works directly with the .dmf format, I had to create a new format to handle future additions to the program.

this document has the goal of detailing the format.

header

the header is 32 bytes long.

size	description
4	"INFO" block ID
4	reserved
1	time base
1	speed 1
1	speed 2
1	initial arpeggio time
4f	ticks per second
- 60 is NTSC
- 50 is PAL
2	pattern length
2	orders length
1	highlight A
1	highlight B
2	instrument count
2	wavetable count
2	sample count
4	pattern count
32	list of sound chips
- possible soundchips:
- 0x00: end of list
- 0x01: YMU759 - 17 channels
- 0x02: Genesis - 10 channels
- 0x03: SMS (SN76489) - 4 channels
- 0x04: Game Boy - 4 channels
- 0x05: PC Engine - 6 channels
- 0x06: NES - 5 channels
- 0x07: C64 (8580) - 3 channels
- 0x08: Arcade (YM2151) - 13 channels
- 0x09: Neo Geo (YM2610) - 13 channels
- bit 6 enables alternate mode:
- 0x42: Genesis extended - 13 channels
- 0x47: C64 (6581) - 3 channels
- 0x49: Neo Geo extended - 16 channels
- bit 7 for non-DefleMask chips:
- 0x80: AY-3-8910 - 3 channels
- 0x81: Amiga - 4 channels
- 0x82: YM2151 alone - 8 channels
- 0x83: YM2612 alone - 6 channels
- 0x84: TIA - 2 channels
- 0x97: Philips SAA1099 - 6 channels
- 0x9a: AY-3-8930 - 3 channels
32	sound chip volumes
- signed char, 64=1.0, 127=~2.0
32	sound chip panning
- signed char, -128=left, 127=right
128	sound chip parameters (TODO)
???	song name
???	song author
24	reserved for compatibility flags
4??	pointers to instruments
4??	pointers to wavetables
4??	pointers to samples
4??	pointers to patterns
???	orders
- a table of shorts
- size=channels*ordLen
- read orders than channels
???	effect columns
- size=channels

size	description
4	"INST" block ID
4	reserved
2	format version (see header)
1	instrument type
- 0: standard
- 1: FM
- 2: Game Boy
- 3: C64
- 4: Amiga/sample
1	reserved
???	instrument name
---	FM instrument data
1	alg
1	feedback
1	fms
1	ams
1	operator count (always 4)
3	reserved
---	FM operator data × 4
1	am
1	ar
1	dr
1	mult
1	rr
1	sl
1	tl
1	dt2
1	rs
1	dt
1	d2r
1	ssgEnv
1	dam
1	dvb
1	egt
1	ksl
1	sus
1	vib
1	ws
1	ksr
12	reserved
---	Game Boy instrument data
1	volume
1	direction
1	length
1	sound length
---	C64 instrument data
1	triangle
1	saw
1	pulse
1	noise
1	attack
1	decay
1	sustain
1	release
2	duty
1	ring mod
1	osc sync
1	to filter
1	init filter
1	vol macro is cutoff
1	resonance
1	low pass
1	band pass
1	high pass
1	channel 3 off
2	cutoff
1	duty macro is absolute
1	filter macro is absolute
---	Amiga instrument data
2	initial sample
14	reserved
---	standard instrument data
4	volume macro length
4	arp macro length
4	duty macro length
4	wave macro length
4	pitch macro length (>=17)
4	extra 1 macro length (>=17)
4	extra 2 macro length (>=17)
4	extra 3 macro length (>=17)
4	volume macro loop
4	arp macro loop
4	duty macro loop
4	wave macro loop
4	pitch macro loop (>=17)
4	extra 1 macro loop (>=17)
4	extra 2 macro loop (>=17)
4	extra 3 macro loop (>=17)
1	arp macro mode
1	reserved (>=17) or volume macro height (>=15) or reserved
1	reserved (>=17) or duty macro height (>=15) or reserved
1	reserved (>=17) or wave macro height (>=15) or reserved
4??	volume macro
4??	arp macro
4??	duty macro
4??	wave macro
4??	pitch macro (>=17)
4??	extra 1 macro (>=17)
4??	extra 2 macro (>=17)
4??	extra 3 macro (>=17)

the instrument format is pretty similar to the file format, but it also stores wavetables and samples used by the instrument.

instrument data follows.

similar to the instrument format...

wavetable data follows.