Re: Capabilities, Anybody?

On 3/14/2024 4:40 PM, Chris M. Thomasson wrote:

On 3/13/2024 10:32 PM, BGB wrote:
[...]

Like, there isn't that huge of a gap between the technologies I had used in my 3D engines, and those I am using in BJX2 and TestKern. Many similar sorts of technologies end up being needed in both cases (say, for example, hierarchical filesystems capable of dealing with mount points, ...).

 Sounds good, BGB. BTW, do you mind if I pick your brain on some of this from time to time? I might even make a new thread so we can do it in public. Or on email. My address is working. Fwiw, here is some of my older modern opengl work:
 https://youtu.be/n13GHyYEfLA
 

Yeah. Kinda artsy...
Feel free to ask anything you want.
I haven't done as much serious graphics stuff recently, nor used much outside of GL 1.x and 2.x functionality. If anything, my usage of newer features had shrank.

I made the music in one of my older MIDI programs. ;^D
 

My case, not much of a musician.
To what extent I had made "music", it was mostly filling out notes based on numeric sequences and similar. A musical composition strategy that I had seen mentioned in videos by both ViHart and Cyriak.
Also doesn't need to be a musical instrument per se, one of my older examples had used DTMF tones (but, not seen a whole lot of music based around using DTMF tones or similar as notes).
Well, that, or a few times transcribing notes from more traditional songs into a MIDI program, and "if by magic" it plays some rendition of the song (though, in these cases, had more often ended up messing with Tracker technology).
Also have noted that I apparently have a sort of reverse slope hearing impairment and don't seem to hear all that much below around 1-2 kHz (at least in terms of sine waves or similar; can hear lots of other stuff though, *).
This may effect how my hearing compares to others. Though, possibly, I may not be the best judge of what others' will find pleasing.
*: I can hear what people are saying, just not over the telephone.
I can hear square and triangle waves and similar at low frequencies, just seemingly not sine waves (tuning forks and similar are basically silent).
Seemingly, for speech, one can discard everything below 2 kHz and it still sounds fairly normal and intelligible, but if one discards everything over 4 kHz, it is unintelligible (seemingly, most of what I rely on here seems to be between 4 kHz and 8 kHz).
Also there are seemingly a lot of things that make sounds that other people hear, but to me are basically silent.
Like, it is kinda weird, like everything sounds normal enough to me, but there is seemingly a whole range of sounds for which, seemingly, I am essentially deaf (and I seem to "hear" a lot of stuff seemingly indirectly via harmonics; and if there are no harmonics, it is silent; but when the harmonics are present, it sounds as-if the fundamental frequency is present as well, even if these lower frequencies are entirely absent in a plot of the spectrum).
Some theory would seem to imply that I should experience more significant impairment though.
...
But, yeah, had implemented FM synthesis for my stuff, but admittedly getting decent sounding music playback is a little harder.
Granted, I suspect in my case the lackluster music is either a limitation of my MIDI playback code, or the design for my "sound chip" cutting too many corners vs the design of the Yamaha chips.
So, general design:
16 channels, FM;
Has the OPL waveforms, but may use triangle waves rather than sine waves, also has a few other PSG-like waveforms (square, sawtooth, ...);
Waveform is generated using a fixed-point accumulator operating at a fixed frequency (IIRC, 20-bits operating at 64 kHz).
Internally, it actually updates channels at 1 MHz, but it updates each FM channel one at a time (in the hardware, there is only actually a single channel), so, say, 1 MHz / 16 -> ~ 64kHz.
My initial mock-ups had sounded more like an OPL than the final design, but this could have been because the E3.F3 values used for volume control aren't quite sufficient or similar. If it mattered more, could fiddle more with it.
Had also experimented with wavetable music (with the design having been extended to potentially also support MOD and S3M playback; with each FM channel also able to function as a PCM channel), but my initial attempts at throwing together a collection of General MIDI wavetable patches from "free" sound effects, left something to be desired (it was a case of trying to find sound effects that were a "close enough" match to the various MIDI instruments, and maybe getting creative, or just reusing the same patches for different instruments).
Though, with these limitations, and some audio-editing issues, generally managed to sound worse than both the FM Synth and some patches derived from the original GUS set.
Well, and as can be noted, Doom and friends don't use MOD or S3M music.
Have also noted that the music playback in ROTT sounds kinda horrid (not yet figured this out).
Also some songs in Doom and Doom 2 seem to have issues with stuck notes, implying there may be some bugs in my MIDI backend code as well (well, either this, or missing NoteOff events).
...