The old speed scaling of 24 was ill-chosen so that triplets resulted in a minor buffer overflow error. This was never caught by anyone until Visual Studio 2019 in debug mode. Presumably all compilers allocate some extra space so this didn't matter. Now 29 increments = double speed and speeds with alternating 52 and 81 result in triplets that are just slightly faster then ordinary bpm i.e. the buffer will be slightly underrun, which probably is unnoticable to the user.
Delays and samples are not implemented yet and thus the tests are skipped, as these require parsing the delay and sample tables also. Various macronames were changed to be more sensible and consistent i.e. ATTAC was changed to ATTACK. GatesLow and GatesHigh was removed for the time being and the tracker will just have to know they are the SHAPE and COLOR parameters. SU_SPEED was changed to take a parameter so the parser picks it up.
The new format is to give either 5 or 6 parameters to SU_SEND, corresponding to local and global send, respectively. For example, a global send:
SU_SEND MONO,AMOUNT(128),VOICE(2),UNIT(0),PORT(1),FLAGS(SEND_POP)
The SU_SEND macro does the address packing into word.
Nasm gives warnings about labels without colons in the end; these were particularly prevalent in struc members: ".size" has be ".size:". Nasm also wasn't happy with extra trailing commas when calling macros.
Sointu.asm / lib stuff lives at the root folder. There is a folder called "go4k", which is where
all go stuff lives. Following the ideas from https://medium.com/@benbjohnson/standard-package-layout-7cdbc8391fc1
the go4k folder is the "domain-model" of the go side, and should have no dependencies.
It contains Unit, Instrument, Synth interface etc. Putting go4k under a sub-folder is actually
in the spirit of Ben, as go4k adds dependency to the go language.
Bridge ties the domain-model to the sointulib through cgo. It returns C.Synth, but
makes sure the C.Synth implements the Synth interface, so others are able to use the
Synth no matter how it actually is done. MockSynth and WebProxy synth are good
prospects for other implementations of Synth.
It is a bit fuzzy where methods like "Play" that have no dependencies other than domain
model structs should go. They probably should live in the go4k package as well.
The file-organization on the Go-side is not at all finalized. But how packages are broken
into files is mostly a documentation issue; it does not affect the users of the packages at
all.
BTW: The name go4k was chosen because Ben advocated naming the subpackages
according to the dependency they introduce AND because the prototype of 4klang was
called go4k (there are still some defines in the 4klang source revealing this). go4k thus
honors our roots but is also not so bad name: it's the main package of a 4k synth tracker,
written in go.
This should make testing easier, as Synth can be assumed to stay the same
during each call. Synth is also the part that we can parse from .asm/.json file
and a Patch can be compiled into a synth. Synth can be eventually made
quite opaque to the user. The user should not need to worry about opcodes
etc.
The LOCALPORT and GLOBALPORT just get numeric parameters (unit, port) and (voice, unit, port), respectively, which should be now quite intuitive as most of the time the port index is one of the parameters visible in the .asm file. Only a few units have extra ports beyond transformed variables. Overall, this should make the parsing of the .asm files a lot easier.
test_render_samples_api.c was added to test the api. bridge.go was modified to reflect that there is no need to check for row manually; su_render_samples already returns the information if a row has ended.
The main interface is render_samples function, which renders several samples in one call,
to limit the number of calls from Go to C. This is compiled into a library, which is then
linked and called from bridge.go.
Builds on both 32-bit and 64-bit executables and all tests (except gm.dls stuff obviously, which was excluded) pass on 64-bit Linux. Cannot test the 32-bit executables, as WSL does not support running 32-bit.
The implentation is through a few macros to handle the fact in 64-bit, all addresses have to be loaded first to register and only offsets are ok. Also, push only supports 64-bit registers in 64-bit, so we have _AX, _BX, _CX etc. defines, which are eax, ebx and ecx on 32bit and rax, rbx and rcx on 64bit.
The stereo opcode variants have bit 1 of the command stream set. The polyphony is split into two parts: 1) polyphony, meaning that voices reuse the same opcodes; 2) multitrack voices, meaning that a track triggers more than voice. They both can be flexible defined in any combinations: for example voice 1 and 2 can be triggered by track 1 and use instrument 1, and voice 3 by track 2/instrument 2 and voice 4 by track 3/instrument 2. This is achieved through the use of bitmasks: in the aforementioned example, bit 1 of su_voicetrack_bitmask would be set, meaning "the voice after voice #1 will be triggered by the same track". On the other hand, bits 1 and 3 of su_polyphony_bitmask would be set to indicate that "the voices after #1 and #3 will reuse the same instruments".
The modulation is now always added during value transformation.
With this, a lot of *_MOD defines could be removed.
The waveform for some tests changed slightly, because when the
value is saved to memory after modulating it, there is some
rounding errors.
