Merge branch 'master' of https://github.com/tildearrow/furnace into nmk112

.github/workflows/build.yml

@@ -2,7 +2,7 @@ name: Build furnace
 
 on:
   push:
-    branches: master
+    branches: [master, esfm-contest]
   pull_request:
     branches: master
 

CMakeLists.txt

@@ -492,6 +492,8 @@ extern/opl/opl3.c
 extern/YM3812-LLE/fmopl2.c
 extern/YMF262-LLE/fmopl3.c
 extern/YMF276-LLE/fmopn2.c
+extern/ESFMu/esfm.c
+extern/ESFMu/esfm_registers.c
 
 src/pch.cpp
 
@@ -700,6 +702,7 @@ src/engine/platform/pv1000.cpp
 src/engine/platform/k053260.cpp
 src/engine/platform/ted.cpp
 src/engine/platform/c140.cpp
+src/engine/platform/esfm.cpp
 src/engine/platform/pcmdac.cpp
 src/engine/platform/dummy.cpp
 
@@ -779,6 +782,7 @@ src/gui/doAction.cpp
 src/gui/editing.cpp
 src/gui/editControls.cpp
 src/gui/effectList.cpp
+src/gui/exportOptions.cpp
 src/gui/findReplace.cpp
 src/gui/fmPreview.cpp
 src/gui/gradient.cpp

README.md

@@ -80,7 +80,8 @@ for other operating systems, you may [build the source](#developer-info).
   - Casio PV-1000
   - TIA used in Atari 2600
   - POKEY used in Atari 8-bit computers
-  - Game Boy
+  - **Game Boy**
+    - including SOFTWARE ENVELOPES (zombie mode)
   - Virtual Boy
   - modern/fantasy:
     - Commander X16 VERA
@@ -360,7 +361,7 @@ you should only save as .dmf if you're really sure, because the DefleMask format
 ---
 # footnotes
 
-copyright (C) 2021-2023 tildearrow and contributors.
+copyright (C) 2021-2024 tildearrow and contributors.
 
 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
 

TODO.md

@@ -1,15 +1,12 @@
 # to-do
 
-- add cheat code to insert bruno time (blank)
-
-# THE REAL TO-DO LIST
-
+- finish color import improvements (settings refactor)
+- new undo stuff
+- fix some bugs
 - finish auto-clone
 
 once you have done all of this (maybe not the first one), release 0.6.1
 
-Furnace is like alcohol...
-
 # and then
 
 - new oscilloscope renderer - custom code that uses texture and fixes two issues: too many vertices, and broken anti-aliasing

doc/2-interface/settings.md

@@ -123,22 +123,21 @@ settings are saved when clicking the **OK** or **Apply** buttons at the bottom o
 - **Note input**: enables note input. disable if you intend to use this device only for binding actions.
 - **Velocity input**: enables velocity input when entering notes in the pattern.
 - **Map MIDI channels to direct channels**: when enabled, notes from MIDI channels will be mapped to channels rather than the cursor position.
+- **Program change pass-through**: when enabled, program change events are sent to each channel as instrument change commands.
+  - this option is only available when the previous one is enabled.
 - **Map Yamaha FM voice data to instruments**: when enabled, Furnace will listen for any transmitted Yamaha SysEx patches.
   - this option is only useful if you have a Yamaha FM synthesizer (e.g. TX81Z).
   - selecting a voice or using the "Voice Transmit?" option will send a patch, and Furnace will create a new instrument with its data.
   - this may also be triggered by clicking on "Receive from TX81Z" in the instrument editor (OPZ only).
 - **Program change is instrument selection**: changes the current instrument when a program change event is received.
+  - this option is not available when "Program change pass-through" is enabled.
 - **Value input style**: changes the way values are entered when the pattern cursor is not in the Note column. the following styles are available:
   - **Disabled/custom**: no value input through MIDI.
   - **Two octaves (0 is C-4, F is D#5)**: maps keys in two octaves to single nibble input. the layout is:
-    - ` - octave n -- octave n+1 -`
-    - ` 1 3   6 8 A   D F   # # # `
-    - `0 2 4 5 7 9 B C E # # # # #`
+    ![two octaves layout 1](MIDI-value-input-1.png)
   - **Raw (note number is value)**: the note number becomes the input value. not useful if you want to input anything above 7F.
   - **Two octaves alternate (lower keys are 0-9, upper keys are A-F)**: maps keys in two octaves, but with a different layout:
-    - ` - octave n -- octave n+1 -`
-    - ` A B   C D E   F #   # # # `
-    - `0 1 2 3 4 5 6 7 8 9 # # # #`
+    ![two octaves layout 2](MIDI-value-input-2.png)
   - **Use dual control change (one for each nibble)**: maps two control change events to the nibbles of a value.
     - **CC of upper nibble**: select the CC number that will change the upper nibble.
     - **CC of lower nibble**: select the CC number that will change the lower nibble.
@@ -149,6 +148,7 @@ settings are saved when clicking the **OK** or **Apply** buttons at the bottom o
     - **Control**: select the CC number that will change the value.
 - **Per-column control change**: when enabled, you can map several control change events to a channel's columns.
 - **Volume curve**: adjust the velocity to volume curve.
+  - the default is 2.0, which matches General MIDI standard.
 - **Actions**: this allows you to bind note input and control change events to actions.
   - **`+`** button: adds a new action.
   - window-with-arrow button: new action with learning! press a button or move a slider/knob/something on your device.
@@ -498,7 +498,7 @@ below all the binds, select a key from the dropdown list to add it. it will appe
 - **Rounded window corners**
 - **Rounded buttons**
 - **Rounded menu corners**
-- **Borders around widgets**: draws thin borders on buttons, checkboxes, text widgets, and the like.
+- **Borders around widgets**: draws borders on buttons, checkboxes, text widgets, and the like.
 
 
 
@@ -509,6 +509,7 @@ below all the binds, select a key from the dropdown list to add it. it will appe
 - **Import**
 - **Export**
 - **Reset defaults**
+- **Guru mode**: exposes all color options (instead of accent colors).
 - **General**
   - **Color scheme type:**
     - **Dark**

doc/3-pattern/effects.md

@@ -93,6 +93,7 @@ not all chips support these effects.
   - this effect is currently incomplete.
 - `F5xx`: **Disable macro.**
 - `F6xx`: **Enable macro.**
+- `F7xx`: **Restart macro.**
   - see macro table at the end of this document for possible values.
 
 additionally, [each chip has its own effects](../7-systems/README.md).

doc/4-instrument/README.md

@@ -1,16 +1,24 @@
 # instrument editor
 
-the instrument editor always starts with this section:
+the instrument editor allows you to edit instruments.
+it can be activated by double-clicking on an instrument in the instrument list.
+
+alternatively, window > instrument editor displays it.
+
+## main
 
 ![top of instrument editor](instrument-editor-top.png)
 
-- top-left numeric dropdown: instrument selector.
-- folder icon: open an instrument file.
-- save icon: save current instrument as a file.
-  - right-clicking gives the option to save a .dmp format DefleMask preset.
-- **Name**: instrument name.
-- **Type**: the system for which the instrument is intended.
-  - if changed, all applicable settings and macros will remain as they are. numbers will not be adjusted.
+**TODO: add descriptions to buttons in the image. it really needs them.**
+
+- **Instrument Selector**: displays a list of instruments in the song.
+- **Open**: open an instrument file.
+- **Save**: save current instrument to a file.
+  - right-click to see additional options, such as saving in DefleMask preset format (.dmp).
+- **Name**: changes the instrument name.
+- **Type**: changes the instrument type (usually chip-specific).
+  - if changed, all applicable settings and macros will remain unchanged.
+  - you may have to adjust them afterwards.
 
 ## instrument types
 
@@ -31,6 +39,7 @@ the following instrument types are available:
 - [VRC6](vrc6.md) - for use with VRC6's PSG sound source.
 - [FM (OPLL)](fm-opll.md) - for use with YM2413.
 - [FM (OPL)](fm-opll.md) - for use with YM3526 (OPL), YM3812 (OPL2) and YMF262 (OPL3).
+- [FM (ESFM)](fm-esfm.md) - for use with ESFM.
 - [FDS](fds.md) - for use with Famicom Disk System sound source.
 - [Virtual Boy](virtual-boy.md) - for use with Virtual Boy.
 - [Namco 163](n163.md) - for use with Namco 163.
@@ -76,59 +85,56 @@ after creating an instrument, open the Instrument Editor and select the "Macros"
 
 ![macro view](macroview.png)
 
-the very first numeric entry sets the visible width of the bars in sequence-type macros. the scrollbar affects the view of all macros at once. there's a matching scrollbar at the bottom underneath all the macros.
+the very first numeric entry sets the visible width of the bars in sequence-type macros. the scrollbar affects the view of all macros at once. there is a matching scrollbar at the bottom underneath all the macros.
 
-each macro has two buttons on the left.
-- macro type (explained below).
-- timing editor, which pops up a small dialog:
-  - **Step Length (ticks)**: determines how many ticks pass before each change of value. default is 1.
-  - **Delay**: delays the start of the macro until this many ticks have passed. default is 0.
-  - the button is highlighted if either of these is set differently from default.
-- release mode. this determines how macro release is handled:
-  - **Active**: jumps to release position.
-  - **Passive**: does not jump to release position. if release position hasn't been reached yet, there will be a delay.
+each macro has the following parameters:
+- macro type (explained below)
+- timing options:
+  - **Step Length (ticks)**: determines the number of ticks between macro steps. default is 1.
+  - **Delay**: delays the macro until this many ticks have elapsed. default is 0.
+  - the button is highlighted if either of these parameters is set to non-default values.
+- release mode: determines how macro release (`===` or `REL` in the pattern) is handled:
+  - **Active**: jumps to release position on release.
+  - **Passive**: does not jump to release position. this will result in delay if release position has not been reached yet.
 
 ## macro types
 
-every macro can be defined though one of three methods, selectable with the leftmost button under the macro type label:
+there are three macro types:
 
-- ![sequence](macro-button-seq.png) **Sequence:** displayed as a bar graph, this is a sequence of numeric values.
-- ![ADSR](macro-button-ADSR.png) **ADSR:** this is a traditional ADSR envelope, defined by the rate of increase and decrease of value over time.
-- ![LFO](macro-button-LFO.png) **LFO:** the Low Frequency Oscillator generates a repeating wave of values.
+- ![sequence](macro-button-seq.png) **Sequence:** a sequence of numeric values.
+- ![ADSR](macro-button-ADSR.png) **ADSR:** this is an attack/decay/sustain/release envelope.
+- ![LFO](macro-button-LFO.png) **LFO:** Low Frequency Oscillator.
 
 ### sequence
 
+this is the most basic macro type. when the instrument is played, every value in the macro will be output sequentially, from left to right.
+
 ![sequence macro editor](macro-seq.png)
 
 ![clipped sequence macro editor](macro-seq-clip.png)
 
 ![bitmask sequence macro editor](macro-seq-bitmask.png)
 
-the number between the macro type label and the macro type button is the macro length in steps. the `-` and `+` buttons change the length of the macro. start out by adding at least a few steps.
+**TODO: once again, text in the image. this sucks.**
 
-the values of the macro can be drawn in the "bar graph" box.
-- arpeggio and pitch macros may have values above or below the visible area; small chevrons will be shown until they are scrolled into view.
-- bitmask-style macros show labels for each of their bits, and these are edited as toggles.
+the Length field allows you to set the number of steps in the sequence.
 
-arpeggio macros have a short bar for setting whether to interpret the values as being "relative" or "fixed".
-- by default, values are offsets **relative** to the note.
-- if clicked on, a value becomes **fixed** and will be played at its corresponding note without regard to the note entered into the pattern.
-  - values are counted from `C-0`. for example, a fixed value of 48 produces a `C-4` note.
-  - fixed values are especially useful for noise instruments with preset periods.
+the sequence view allows you to edit the macro.
+- press and hold the left mouse button to start drawing. release to stop drawing.
+- press and hold the right mouse button to draw a line.
+  - the start point will be set to the cursor position.
+  - move the cursor to change the end point.
+  - release to finish drawing the line.
 
-below this is a short bar that controls macro loop and release.
-- click to set the start point of a loop; the end point is the last value or release point. it appears as half-height bars. right-click to remove the loop.
-- shift-click to set the release point. when played, the macro will hold here until the note is released. it appears as a full-height bar. right-click to remove the release point.
+the sequence view may be adjusted using the following combinations:
+- hold Ctrl and use the scroll wheel to zoom horizontally.
+- hold Ctrl-Shift and use the scroll wheel to zoom vertically.
+- the scrollbar at the right allows you to scroll vertically (if possible).
+- you may hold Shift and use the scroll wheel to scroll vertically as well.
 
-finally, the sequence of values can be directly edited in the text box at the bottom.
-- the loop start is entered as a `|`.
-- the release point is entered as a `/`.
-- in arpeggio macros, a value starting with a `@` is a fixed value as described above.
-- in bitmask-style macros, the values are added up in binary and converted to decimal. see [the hexadecimal guide](../1-intro/hex.md) for more info.
-
-in all cases except bitmask macros, right-clicking on the graph opens up an editing menu:
-- **copy**: copies the macro.
-- **paste**: pastes the macro in the clipboard.
+right-click on the sequence view to open a menu:
+- **copy**: copy this macro to clipboard.
+- **paste**: pastes the macro.
 - **clear**: clears the macro.
 - **clear contents**: resets all values to 0.
 - **offset**:
@@ -139,19 +145,46 @@ in all cases except bitmask macros, right-clicking on the graph opens up an edit
   - **Y**: multiplies all values by the scale factor, clipping them if they would exceed the allowed range.
 - **randomize**: replaces all values with random values between **Min** and **Max**.
 
+arpeggio and pitch macros may have values above or below the visible area. indicators will be shown until they are scrolled into view.
+
+bitmask-style macros show labels for each of their bits. these are edited as toggles.
+- drawing lines is not possible in these macros.
+
+under the sequence view there is a bar that allows you to set loop and release points.
+- click to set the loop start point; the end point is the last step or release point.
+  - right-click to remove the loop point.
+- shift-click to set the release point.
+  - the macro will stop at the release point until the note is released (`===` or `REL`).
+    - if the loop point is set, and it is placed before the release point, the macro will loop until note release instead.
+  - shift-right-click to remove the release point.
+
+arpeggio macros have an additional bar under the sequence view to set steps to "relative" or "fixed":
+- by default, step values are offsets **relative** to the note.
+- if clicked on, a step value becomes **fixed** and will be played at its corresponding note without regard to the currently playing note.
+  - values are counted from `C-0`. for example, a fixed value of 48 produces a `C-4` note.
+  - fixed values are especially useful for noise or percussion.
+
+the sequence can be edited in the text input field at the very bottom. the following symbols have special meanings:
+- `|`: loop point.
+- `/`: release point.
+- in arpeggio macros, `@` prefixed to a value indicates that it is a fixed value as described above.
+
+in bitmask-style macros, the values are added up in binary and converted to decimal.
+
 ### ADSR
 
 ![ADSR macro editor](macro-ADSR.png)
 
-- **Bottom** and **Top** determine the range of outputs generated by the macro. (Bottom can be larger than Top to invert the envelope!) All outputs will be between these two values.
+- **Bottom** and **Top** determine the macro's output range (Bottom can be larger than Top to invert the envelope!). all outputs will be between these two values.
 - Attack, Decay, Sustain, SusDecay, and Release accept inputs between 0 to 255. these are scaled to the distance between Bottom and Top.
-- **Attack** is how much the value moves toward Top with each tick.
-- **Hold** sets how many ticks to stay at Top before Decay.
-- **Decay** is how much the value moves to the Sustain level.
-- **Sustain** is how far from Bottom the value stays while the note is held.
-- **SusTime** is how many ticks to stay at Sustain until SusDecay.
-- **SusDecay** is how much the value moves toward Bottom with each tick while the note is held.
-- **Release** is how much the value moves toward Bottom with each tick after the note is released.
+  - the output starts at Bottom.
+  - **Attack** is how much the output moves toward Top with each tick.
+  - **Hold** sets how many ticks to stay at Top before Decay.
+  - **Decay** is how much the output moves to the Sustain level.
+  - **Sustain** is how far from Bottom the value stays while the note is on.
+  - **SusTime** is how many ticks to stay at Sustain until SusDecay.
+  - **SusDecay** is how much the output moves toward Bottom with each tick while the note is on.
+  - **Release** is how much the output moves toward Bottom with each tick after the note is released.
 
 ![macro ADSR chart](macro-ADSRchart.png)
 
@@ -159,10 +192,13 @@ in all cases except bitmask macros, right-clicking on the graph opens up an edit
 
 ![LFO macro editor](macro-LFO.png)
 
-- **Bottom** and **Top** determine the range of values generated by the macro. (Bottom can be larger than Top to invert the waveform!)
-- **Speed** is how quickly the values change - the frequency of the oscillator.
-- **Phase** is which part of the waveform the macro will start at, measured in 1/1024 increments.
-- **Shape** is the waveform used. triangle is the default, and Saw and Square are exactly as they say.
+- **Bottom** and **Top** determine the macro's output range (Bottom can be larger than Top to invert the waveform!).
+- **Speed** is how quickly the LFO position moves.
+- **Phase** defines the starting LFO position, measured in 1/1024 increments.
+- **Shape** is the waveform of the LFO. there are three waveforms:
+  - Triangle: Bottom > Top > Bottom.
+  - Saw: moves from Bottom to Top, and then jumps back to Bottom.
+  - Square: alternates between Bottom and Top.
 
 
 

doc/4-instrument/fm-esfm.md

@@ -0,0 +1,77 @@
+# ESFM instrument editor
+
+the ESFM editor is divided into 6 tabs:
+
+- **FM**: for controlling the basic parameters of FM sound source.
+- **Macros (OP1)**: for macros controlling FM parameters of operator 1.
+- **Macros (OP2)**: for macros controlling FM parameters of operator 2.
+- **Macros (OP3)**: for macros controlling FM parameters of operator 3.
+- **Macros (OP4)**: for macros controlling FM parameters of operator 4.
+- **Macros**: for other macros (volume/arp/pitch/pan/noise mode).
+
+## FM
+
+ESFM is four-operator, but it is different from the rest of FM chips.
+
+the concept of an algorithm does not exist in ESFM. instead, modulation routing is arbitrary, with each operator having output level and modulation input parameters.
+
+these apply to the instrument as a whole:
+- **OP4 Noise Mode**: determines the mode used to produce noise in operator 4.
+  - Normal: noise is disabled.
+  - Snare: takes the snare noise generation mode from OPL. square + noise.
+  - HiHat: ring modulates with operator 3 and adds noise.
+  - Top: ring modulates with operator 3 and double pitch modulation input.
+    - this mode is not emulated correctly. subject to change!
+
+these apply to each operator:
+- the crossed-arrows button can be dragged to rearrange operators.
+- **Amplitude Modulation (AM)**: makes the operator affected by LFO tremolo.
+- **Sustain flag (SUS)**: when enabled, value of Sustain Level is in effect.
+- **AM Depth (AMD)**: when enabled, LFO tremolo is deeper.
+- **Attack Rate (AR)**: determines the rising time for the sound. the bigger the value, the faster the attack (0 to 15).
+- **Decay Rate (DR)**: determines the diminishing time for the sound. the higher the value, the shorter the decay. it's the initial amplitude decay rate (0 to 15).
+- **Sustain Level (SL)**: determines the point at which the sound ceases to decay and changes to a sound having a constant level. the sustain level is expressed as a fraction of the maximum level (0 to 15).
+- **Release Rate (RR)**: determines the rate at which the sound disappears after note off. the higher the value, the shorter the release (0 to 15).
+
+- **Total Level (TL)**: represents the envelope’s highest amplitude, with 0 being the largest and 63 (decimal) the smallest. a change of one unit is about 0.75 dB.
+- **Output Level (OL)**: determines the volume at which the operator will be output.
+- **Modulation Input (MI)**: determines how much to take from the previous operator for modulation.
+  - this controls feedback level in the case of operator 1.
+- **Key Scale Level (KSL)**: also known as "Level Scale". determines the degree to which the amplitude decreases according to the pitch.
+
+![FM ADSR chart](FM-ADSRchart.png)
+
+- **Key Scale Rate (KSR)**: also known as "Rate Scale". determines the degree to which the envelope execution speed increases according to the pitch.
+- **Frequency Multiplier (MULT)**: sets the coarse pitch offset in relation to the note (0 to 15). 0 is -1 octave, 1 is 0 octaves, 2 is 1 octave, 3 is 1 octave 7 semitones, and so on.
+  - note that values 11, 13 and 14 behave as 10, 12 and 12 respectively.
+- **Waveform Select (WS)**: changes the waveform of the operator (0 to 7).
+- **Vibrato (VIB)**: makes the operator affected by LFO vibrato.
+- **FM Depth (FMD)**: when enabled, vibrato is deeper.
+
+- **Tune**: sets the coarse tune of the operator.
+- **Detune**: sets the fine tune of the operator.
+
+- **Left (L)**: output on the left channel.
+- **Right (R)**: output on the right channel.
+
+### fixed frequency mode
+
+each operator has a Fixed Frequency mode. once enabled, the operator runs at the specified frequency regardless of the note.
+
+## macros
+
+these macros allow you to control several parameters of FM per tick.
+
+## OP1-OP4 Macros
+
+all parameters are listed above.
+
+## Macros
+
+- **Volume**: volume sequence.
+- **Arpeggio**: pitch sequence.
+- **OP4 Noise Mode**: noise mode sequence.
+- **Panning**: enables output on left/right channels.
+- **Pitch**: fine pitch.
+  - **Relative**: when enabled, pitch changes are relative to the current pitch.
+- **Phase Reset**: restarts all operators and resets the waveform to its start.

doc/7-systems/README.md

@@ -108,8 +108,9 @@ this is the full list of chips that Furnace supports.
 - [VRC6](vrc6.md)
 - [WonderSwan](wonderswan.md)
 - [X1-010](x1-010.md)
-- [VRC7, Y8950, YM3526, YM3812 and YMF262 (OPL)](opl.md)
-- [YM2413 (OPLL)](opll.md)
+- [Y8950, YM3526, YM3812 and YMF262 (OPL)](opl.md)
+- [ESFM](esfm.md)
+- [VRC7 and YM2413 (OPLL)](opll.md)
 - [YM2414 (OPZ)](opz.md)
 - [YM2151 (OPM)](ym2151.md)
 - [YM2203 (OPN)](ym2203.md)

doc/7-systems/esfm.md

@@ -0,0 +1,101 @@
+# ESS ESFM
+
+an enhanced version of Yamaha's OPL3, adding many features which weren't present on the original chip, such as 4-op on all channels, coarse/fine detune, per-op panning, envelope delay, noise generator and advanced modulation routing (no more algorithms!).
+
+the technology was present in many of ESS' sound cards (the ES1xxx series in particular).
+
+## effects
+
+- `10xy`: **set AM depth.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is either `0` (1dB, shallow) or `1` (4.8dB, deep).
+- `12xx`: **set operator 1 level.**
+- `13xx`: **set operator 2 level.**
+- `14xx`: **set operator 3 level.**
+- `15xx`: **set operator 4 level.**
+- `16xy`: **set multiplier of operator.**
+  - `x` is the operator (1-4).
+  - `y` is the new MULT value..
+- `17xy`: **set vibrato depth.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is either `0` (normal) or `1` (double).
+- `19xx`: **set attack of all operators.**
+- `1Axx`: **set attack of operator 1.**
+- `1Bxx`: **set attack of operator 2.**
+- `1Cxx`: **set attack of operator 3.**
+- `1Dxx`: **set attack of operator 4.**
+- `20xy`: **set panning of operator 1.**
+  - `x` determines whether to output on left.
+  - `y` determines whether to output on right.
+- `21xy`: **set panning of operator 2.**
+  - `x` determines whether to output on left.
+  - `y` determines whether to output on right.
+- `22xy`: **set panning of operator 3.**
+  - `x` determines whether to output on left.
+  - `y` determines whether to output on right.
+- `23xy`: **set panning of operator 4.**
+  - `x` determines whether to output on left.
+  - `y` determines whether to output on right.
+- `24xy`: **set output level of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `25xy`: **set modulation input level of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `26xy`: **set envelope delay of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `27xx`: **set operator 4 noise mode.**
+  - `0`: noise off
+  - `1`: square + noise
+  - `2`: ring mod from operator 3 + noise
+  - `3`: ring mod from operator 3 + double pitch modulation input
+    - note: emulation issues. subject to change!
+- `2Axy`: **set waveform of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `2Exx`: **enable envelope hard reset.**
+- `2Fxy`: **set fixed frequency block (octave).**
+  - `x` is the operator from 1 to 4.
+  - `y` is the block/octave from 0 to 7.
+- `3xyy`: **set fixed frequency f-num.**
+  - `x` contains operator number and high bits of f-num may be any of the following:
+    - `0` to `3` for operator 1
+    - `4` to `7` for operator 2
+    - `8` to `B` for operator 3
+    - `C` to `F` for operator 4
+  - `y` are the lower bits of f-num.
+- `40xx`: **set operator 1 detune.**
+- `41xx`: **set operator 1 detune.**
+- `42xx`: **set operator 1 detune.**
+- `43xx`: **set operator 1 detune.**
+- `50xy`: **set AM of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` determines whether AM is on.
+- `51xy`: **set SL of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `52xy`: **set RR of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `53xy`: **set VIB of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` determines whether VIB is on.
+- `54xy`: **set KSL of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` is the value.
+- `55xy`: **set SUS of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` determines whether SUS is on.
+- `56xx`: **set DR of all operators.**
+- `57xx`: **set DR of operator 1.**
+- `58xx`: **set DR of operator 2.**
+- `59xx`: **set DR of operator 3.**
+- `5Axx`: **set DR of operator 4.**
+- `5Bxy`: **set KSR of operator.**
+  - `x` is the operator from 1 to 4. a value of `0` means "all operators".
+  - `y` determines whether KSR is on.
+
+## info
+
+this chip uses the [FM (ESFM)](../4-instrument/fm-esfm.md) instrument editor.

doc/7-systems/n163.md

@@ -6,7 +6,7 @@ it has 256 nibbles (128 bytes) of internal RAM which is shared between channel s
 
 wavetables are variable in size and may be allocated anywhere in RAM. at least 128 nibbles (64 bytes) can be dedicated to waves, with more available if not all channels are used - waveform RAM area becomes smaller as more channels are activated, since channel registers consume 8 bytes for each channel.
 
-Namco 163 uses time-division multiplexing for its output. this means that only one channel is output per sample (like OPLL and OPN2). therefore, its sound quality gets worse as more channels are activated.
+Namco 163 uses time-division multiplexing (TDM) for its output. this means that only one channel is output per sample (like OPLL and OPN2). therefore, its sound quality gets worse as more channels are activated.
 
 ## waveform load position versus waveform position
 
@@ -39,6 +39,13 @@ if the waveform changes (e.g. ins change, wave macro or wave synth), or the **lo
   - make sure to use `21xx` first!
 - `21xx`: **set position for 20xx.**
 
+## chip options
+
+- **Initial channel limit**: sets the number of channels that will be active. higher values reduce volume and make TDM artifacts more noticeable.
+- **Disable hissing**: remove TDM artifacts by mixing. sacrifices some accuracy!
+- **Scale frequency to wave length**: automatically adjusts note frequency to account for differing waveform lengths.
+  - if disabled, note frequencies ignore waveveform length. this is how FamiTracker behaves.
+
 ## info
 
 this chip uses the [Namco 163](../4-instrument/n163.md) instrument editor.

doc/7-systems/opll.md

@@ -15,8 +15,8 @@ the YM2413 is equipped with the following features:
 - a drum/percussion mode, replacing the last 3 voices with 5 rhythm channels, with drum mode tones hard-defined in the chip itself, like FM instruments. only pitch might be altered.
   - drum mode works like following: FM channel 7 is for Kick Drum, which is a normal FM channel but routed through mixer twice for 2× volume, like all drum sounds. FM channel 8 splits to Snare, Drum, and Hi-Hat. Snare Drum is the carrier and it works with a special 1 bit noise generator combined with a square wave, all possible by overriding phase-generator with some different synthesis method. Hi-Hat is the modulator and it works with the noise generator and also the special synthesis. channel 9 splits to Top-Cymbal and Tom-Tom, Top-Cymbal is the carrier and only has the special synthesis, while Tom-Tom is basically a 1op wave. 
   - special synthesis mentioned already is: 5 square waves are gathered from 4×, 64× and 128× the pitch of channel 8 and 16× and 64× the pitch of channel 9 and they go through a process where 2 HH bits OR'd together, then 1 HH and 1 TC bit OR'd, then the two TC bits OR'd together, and those 3 results get XOR'd.
-- 1 user-definable patch (this patch can be changed throughout the course of the song)
-- 15 pre-defined patches which can all be used at the same time
+- **1 user-definable patch (this patch can be changed throughout the course of the song)**
+- **15 pre-defined patches which can all be used at the same time**
 - support for ADSR on both the modulator and the carrier
 - sine and half-sine based FM synthesis
 - 9 octave note control

doc/8-advanced/chanosc.md

@@ -33,6 +33,7 @@ right-clicking the view will display the configuration view shown above:
   - `%v`: volume (decimal)
   - `%V`: volume (percentage)
   - `%b`: volume (hex)
+  - `%l`: new line
   - `%%`: percent sign
 
 click on OK to return to the main view.

doc/README.md

@@ -27,7 +27,7 @@ the index follows.
 
 ## information
 
-copyright © 2023 tildearrow and other authors.
+copyright © 2024 tildearrow and other authors.
 
 this documentation is under the [Creative Commons Attribution 3.0 Unported](https://creativecommons.org/licenses/by/3.0/) license.
 you may reproduce, modify and/or distribute this documentation provided this copyright notice (including license and attribution) is present and any necessary disclaimers whether modifications have been made.

extern/ESFMu/.gitignore

@@ -0,0 +1 @@
+test_scripts/*

extern/ESFMu/LICENSE

@@ -0,0 +1,504 @@
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+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
+    USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random
+  Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!

extern/ESFMu/README.md

@@ -0,0 +1,67 @@
+# ESFMu
+
+An emulator for the ESS "ESFM" enhanced OPL3 clone, based on Nuke.YKT's **Nuked OPL3** and reverse-engineering efforts from the community.
+
+## Acknowledgements
+
+I'd like to thank:
+
+- **Nuke.YKT**
+  - Developer of **Nuked OPL3**, which was the basis for **ESFMu**'s code and also a great learning resource on Yamaha FM synthesis for myself.
+  - Nuke.YKT also gives shoutouts on behalf of **Nuked OPL3** to:
+    >- MAME Development Team(Jarek Burczynski, Tatsuyuki Satoh):
+    >    - Feedback and Rhythm part calculation information.
+    >- forums.submarine.org.uk(carbon14, opl3):
+    >    - Tremolo and phase generator calculation information.
+    >- OPLx decapsulated(Matthew Gambrell, Olli Niemitalo):
+    >    - OPL2 ROMs.
+    >- siliconpr0n.org(John McMaster, digshadow):
+    >    - YMF262 and VRC VII decaps and die shots.
+- **rainwarrior**
+  - For performing the initial research on ESFM drivers and documenting ESS's patent on native mode operator organization.
+- **jwt27**
+  - For kickstarting the ESFM research project and compiling rainwarrior's findings and more in an accessible document ("ESFM Demystified").
+- **pachuco/CatButts**
+  - For documenting ESS's patent on ESFM's feedback implementation, which was vital in getting **ESFMu**'s sound output to be accurate.
+- And everybody who helped out with real hardware testing
+
+## Usage
+
+To use **ESFMu**:
+
+- include the **esfm.h** header file into your source code
+- include the **esfm.c** and **esfm_registers.c** files into your build and link process
+- declare or allocate a variable of type `esfm_chip` somewhere in your code - this will hold the chip's state
+- use the function interface defined in **esfm.h** to interact with the `esfm_chip` structure
+
+## Function interface
+
+If you're familiar with **Nuked OPL3**, you'll find many similarities in the function interface provided by **ESFMu**. There are a few things to point out, however:
+
+### Buffered writes
+
+Just like **Nuked OPL3**, **ESFMu** offers buffered register writes. However, it offers them in two flavors: "legacy" and fast.
+
+The fast buffered register writes (`ESFM_write_reg_buffered_fast`) are recommended, since they offer minimal latency which is close to the behavior you'd get with the actual ESS drivers on Windows.
+
+The "legacy" buffered register writes are only recommended for specific cases, such as programs seeking for a shortcut to emulate the write delays from some sound drivers.
+
+### Port-level access
+
+Unlike **Nuked OPL3**, **ESFMu** actually allows port-level access to the ESFM interface. This is relevant because the ESFM port interface is actually modal, meaning that its behavior changes depending on whether the chip is set to emulation (OPL3 compatibility) mode or native (ESFM) mode.
+
+Using port-level access allows for applications to not need to keep track of whether the chip is in native mode or not, nor to perform the port handling logic on their side.
+
+Applications that use the register-level access, on the other hand, need to take care to either stick to only one of the operating modes (either native or emulation), or handle the port mapping logic on their own side.
+
+### Register readback
+
+ESFM allows for register contents to be read back through its ports, and **ESFMu** implements this functionality, both via dedicated register read functions and via the port read interface.
+
+Note that in ESFM, register contents can only be read back when the chip is set to native (ESFM) mode, not when the chip is in emulation mode (i.e. OPL3 compatibility mode).
+
+## Licensing
+
+**ESFMu** is highly based on **Nuked OPL3**, which is licensed under the GNU Lesser General Public License version 2.1 or later. Therefore, **ESFMu** is licensed under the same license.
+
+If you'd like to obtain a grant to use **ESFMu** under different terms, you should get in contact with [Nuke.YKT](https://github.com/nukeykt) (author of **Nuked OPL3**) as well as with [Kagamiin~](https://github.com/Kagamiin) (yours truly).

extern/ESFMu/esfm.h

@@ -0,0 +1,310 @@
+/*
+ * ESFMu: emulator for the ESS "ESFM" enhanced OPL3 clone
+ * Copyright (C) 2023 Kagamiin~
+ *
+ * ESFMu is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 2.1
+ * of the License, or (at your option) any later version.
+ *
+ * ESFMu is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with ESFMu. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/*
+ * ESFMu wouldn't have been possible without the hard work and dedication of
+ * the retro computer hardware research and preservation community.
+ *
+ * I'd like to thank:
+ *  - Nuke.YKT
+ *        Developer of Nuked OPL3, which was the basis for ESFMu's code and
+ *        also a great learning resource on Yamaha FM synthesis for myself.
+ *        Nuke.YKT also gives shoutouts on behalf of Nuked OPL3 to:
+ *        - MAME Development Team(Jarek Burczynski, Tatsuyuki Satoh):
+ *              Feedback and Rhythm part calculation information.
+ *        - forums.submarine.org.uk(carbon14, opl3):
+ *              Tremolo and phase generator calculation information.
+ *        - OPLx decapsulated(Matthew Gambrell, Olli Niemitalo):
+ *              OPL2 ROMs.
+ *        - siliconpr0n.org(John McMaster, digshadow):
+ *              YMF262 and VRC VII decaps and die shots.
+ * - rainwarrior
+ *       For performing the initial research on ESFM drivers and documenting
+ *       ESS's patent on native mode operator organization.
+ * - jwt27
+ *       For kickstarting the ESFM research project and compiling rainwarrior's
+ *       findings and more in an accessible document ("ESFM Demystified").
+ * - pachuco/CatButts
+ *       For documenting ESS's patent on ESFM's feedback implementation, which
+ *       was vital in getting ESFMu's sound output to be accurate.
+ * - And everybody who helped out with real hardware testing
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct _esfm_slot esfm_slot;
+typedef struct _esfm_slot_internal esfm_slot_internal;
+typedef struct _esfm_channel esfm_channel;
+typedef struct _esfm_chip esfm_chip;
+
+
+void ESFM_init (esfm_chip *chip);
+void ESFM_write_reg (esfm_chip *chip, uint16_t address, uint8_t data);
+void ESFM_write_reg_buffered (esfm_chip *chip, uint16_t address, uint8_t data);
+void ESFM_write_reg_buffered_fast (esfm_chip *chip, uint16_t address, uint8_t data);
+void ESFM_write_port (esfm_chip *chip, uint8_t offset, uint8_t data);
+uint8_t ESFM_readback_reg (esfm_chip *chip, uint16_t address);
+uint8_t ESFM_read_port (esfm_chip *chip, uint8_t offset);
+void ESFM_generate(esfm_chip *chip, int16_t *buf);
+void ESFM_generate_stream(esfm_chip *chip, int16_t *sndptr, uint32_t num_samples);
+int16_t ESFM_get_channel_output_native(esfm_chip *chip, int channel_idx);
+
+
+// These are fake types just for syntax sugar.
+// Beware of their underlying types when reading/writing to them.
+#ifndef __NO_ESFM_FAST_TYPES
+#ifndef __ESFM_FAST_TYPES
+#define __ESFM_FAST_TYPES
+#endif
+#endif
+
+#ifdef __ESFM_FAST_TYPES
+
+typedef uint_fast8_t flag;
+typedef uint_fast8_t uint2;
+typedef uint_fast8_t uint3;
+typedef uint_fast8_t uint4;
+typedef uint_fast8_t uint5;
+typedef uint_fast8_t uint6;
+typedef uint_fast8_t uint8;
+typedef uint_fast16_t uint9;
+typedef uint_fast16_t uint10;
+typedef uint_fast16_t uint11;
+typedef uint_fast16_t uint12;
+typedef uint_fast16_t uint16;
+typedef uint_fast32_t uint19;
+typedef uint_fast32_t uint23;
+typedef uint_fast32_t uint32;
+typedef uint_fast64_t uint36;
+
+typedef int_fast16_t int13;
+typedef int_fast16_t int14;
+typedef int_fast16_t int16;
+typedef int_fast32_t int32;
+
+#else
+typedef uint8_t flag;
+typedef uint8_t uint2;
+typedef uint8_t uint3;
+typedef uint8_t uint4;
+typedef uint8_t uint5;
+typedef uint8_t uint6;
+typedef uint8_t uint8;
+typedef uint16_t uint9;
+typedef uint16_t uint10;
+typedef uint16_t uint11;
+typedef uint16_t uint12;
+typedef uint16_t uint16;
+typedef uint32_t uint19;
+typedef uint32_t uint23;
+typedef uint32_t uint32;
+typedef uint64_t uint36;
+
+typedef int16_t int13;
+typedef int16_t int14;
+typedef int16_t int16;
+typedef int32_t int32;
+
+#endif
+
+enum eg_states
+{
+	EG_ATTACK,
+	EG_DECAY,
+	EG_SUSTAIN,
+	EG_RELEASE
+};
+
+
+typedef struct _esfm_write_buf
+{
+	uint64_t timestamp;
+	uint16_t address;
+	uint8_t data;
+	flag valid;
+
+} esfm_write_buf;
+
+typedef struct _emu_slot_channel_mapping
+{
+	int channel_idx;
+	int slot_idx;
+
+} emu_slot_channel_mapping;
+
+typedef struct _esfm_slot_internal
+{
+	uint9 eg_position;
+	uint9 eg_ksl_offset;
+	uint10 eg_output;
+
+	uint4 keyscale;
+
+	int13 output;
+	int13 emu_output_enable;
+	int13 emu_mod_enable;
+	int13 feedback_buf;
+	int13 *mod_input;
+
+	uint19 phase_acc;
+	uint10 phase_out;
+	flag phase_reset;
+	flag *key_on;
+	flag key_on_gate;
+
+	uint2 eg_state;
+	flag eg_delay_run;
+	flag eg_delay_transitioned_10;
+	flag eg_delay_transitioned_10_gate;
+	flag eg_delay_transitioned_01;
+	flag eg_delay_transitioned_01_gate;
+	uint16 eg_delay_counter;
+	uint16 eg_delay_counter_compare;
+
+} esfm_slot_internal;
+
+struct _esfm_slot
+{
+	// Metadata
+	esfm_channel *channel;
+	esfm_chip *chip;
+	uint2 slot_idx;
+
+	// Register data
+	int13 out_enable[2];
+	uint10 f_num;
+	uint3 block;
+	uint3 output_level;
+	// a.k.a. feedback level in emu mode
+	uint3 mod_in_level;
+
+	uint6 t_level;
+	uint4 mult;
+	uint3 waveform;
+	// Only for 4th slot
+	uint2 rhy_noise;
+
+	uint4 attack_rate;
+	uint4 decay_rate;
+	uint4 sustain_lvl;
+	uint4 release_rate;
+
+	flag tremolo_en;
+	flag tremolo_deep;
+	flag vibrato_en;
+	flag vibrato_deep;
+	flag emu_connection_typ;
+	flag env_sustaining;
+	flag ksr;
+	uint2 ksl;
+	uint3 env_delay;
+	// overlaps with env_delay bit 0
+	// TODO: check if emu mode only uses this, or if it actually overwrites the channel field used by native mode
+	flag emu_key_on;
+
+	// Internal state
+	esfm_slot_internal in;
+};
+
+struct _esfm_channel
+{
+	esfm_chip *chip;
+	esfm_slot slots[4];
+	uint5 channel_idx;
+	int16 output[2];
+	flag key_on;
+	flag emu_mode_4op_enable;
+	// Only for 17th and 18th channels
+	flag key_on_2;
+	flag emu_mode_4op_enable_2;
+};
+
+#define ESFM_WRITEBUF_SIZE 1024
+#define ESFM_WRITEBUF_DELAY 2
+
+struct _esfm_chip
+{
+	esfm_channel channels[18];
+	int32 output_accm[2];
+	uint_fast16_t addr_latch;
+
+	flag emu_wavesel_enable;
+	flag emu_newmode;
+	flag native_mode;
+
+	flag keyscale_mode;
+
+	// Global state
+	uint36 eg_timer;
+	uint10 global_timer;
+	uint8 eg_clocks;
+	flag eg_tick;
+	flag eg_timer_overflow;
+	uint8 tremolo;
+	uint8 tremolo_pos;
+	uint8 vibrato_pos;
+	uint23 lfsr;
+
+	flag rm_hh_bit2;
+	flag rm_hh_bit3;
+	flag rm_hh_bit7;
+	flag rm_hh_bit8;
+	flag rm_tc_bit3;
+	flag rm_tc_bit5;
+
+	// 0xbd register in emulation mode, exposed in 0x4bd in native mode
+	// ("bass drum" register)
+	uint8 emu_rhy_mode_flags;
+
+	flag emu_vibrato_deep;
+	flag emu_tremolo_deep;
+
+	uint8 timer_reload[2];
+	uint8 timer_counter[2];
+	flag timer_enable[2];
+	flag timer_mask[2];
+	flag timer_overflow[2];
+	flag irq_bit;
+
+	// Halts the envelope generators from advancing.
+	flag test_bit_eg_halt;
+	/*
+	 * Activates some sort of waveform test mode that amplifies the output volume greatly
+	 * and continuously shifts the waveform table downwards, possibly also outputting the
+	 * waveform's derivative? (it's so weird!)
+	 */
+	flag test_bit_distort;
+	// Appears to attenuate the output by about 3 dB.
+	flag test_bit_attenuate;
+	// Resets all phase generators and holds them in the reset state while this bit is set.
+	flag test_bit_phase_stop_reset;
+
+	esfm_write_buf write_buf[ESFM_WRITEBUF_SIZE];
+	size_t write_buf_start;
+	size_t write_buf_end;
+	uint64_t write_buf_timestamp;
+};
+
+#ifdef __cplusplus
+}
+#endif