Search found 1146 matches

by 93143
Fri Jul 03, 2020 1:25 am
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 21
Views: 3573

Re: SNES Doom development, Randy Linden

I guess I'm the only one who's suddenly developed a semi-obsession with SNES Doom after watching the Randy Linden interview. Once the source code drops, it will hopefully be possible to figure out how he did what he did in detail, and from that whether it's possible to materially improve it in certa...
by 93143
Mon Jun 22, 2020 1:58 am
Forum: General Stuff
Topic: Digital Foundry Retro Doom port comparison
Replies: 41
Views: 9711

Re: Digital Foundry Retro Doom port comparison

The idea is to be able to draw in double-wide pixels without having to draw and DMA each pixel twice. The pixels in the graphics data would alternate between line N and line N+1, and by manipulating mosaic and scroll with HDMA you turn this: ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ into this: ▄▄ ▄▄ ▄▄ ▄▄ ▀▀ ▀▀ ▀▀ ▀▀ I'd be...
by 93143
Sat Jun 20, 2020 4:39 pm
Forum: General Stuff
Topic: We need a better name for "Adventure Games."
Replies: 39
Views: 2526

Re: We need a better name for "Adventure Games."

Whenever I hear the term "adventure" I picture someone picking up a sword and slaying dragons. Wouldn't that be a "big-game trophy hunting game", or a "fantasy safari slayer game"? I would say that real adventures are about solving any kind of bigger or smaller problems that are unexpectedly encoun...
by 93143
Tue Jun 16, 2020 4:34 pm
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 21
Views: 3573

Re: SNES Doom development, Randy Linden

So I've had a quick look through the Doom code in Mesen-S, and I don't see a whole lot of ldw; color; plot; swap; color; plot or anything like that. I do see a fair bit of getc; plot; plot; dec R1; dec R1; dec R2 (with other stuff mixed in, control code and branches and such). In other words: get a ...
by 93143
Fri Jun 12, 2020 9:47 pm
Forum: SNESdev
Topic: Ideas for compressing BRR samples further
Replies: 18
Views: 1373

Re: Ideas for compressing BRR samples further

Not necessarily. Why should every sample played have to be decompressed live? It could be that a number of the instruments are short or low-frequency samples that don't take up much space and therefore don't need compression. Maybe some samples are complex waveforms that don't compress well so there...
by 93143
Fri Jun 12, 2020 6:06 pm
Forum: SNESdev
Topic: Ideas for compressing BRR samples further
Replies: 18
Views: 1373

Re: Ideas for compressing BRR samples further

The data has to be decompressed from LZ4 into BRR before being played by the SPC700. That's exactly what the general consensus that this method 'doesn't work' means: that it's not going to pack more in the audio RAM because the decompressed result will ultimately have to be stored in the audio RAM....
by 93143
Thu Jun 11, 2020 6:34 pm
Forum: SNESdev
Topic: Ideas for compressing BRR samples further
Replies: 18
Views: 1373

Re: Ideas for compressing BRR samples further

Found another post by the same guy saying that he's tried it and it doesn't work. I wonder if the disappointing saw results are indicative of what might happen if you try to generalize this to more information-dense waveforms... Of course there are sounds that one might wish to play on a SNES that a...
by 93143
Thu Jun 11, 2020 6:01 pm
Forum: SNESdev
Topic: Ideas for compressing BRR samples further
Replies: 18
Views: 1373

Re: Ideas for compressing BRR samples further

Interesting. The conventional wisdom was that this doesn't work. I'm not surprised that it depends somewhat on the nature of the sample; sawtooth waves do have twice as many harmonics as square waves... Those LZ4 numbers are for packed BRR, not packed PCM, right? Those numbers are comparable to what...
by 93143
Mon Jun 08, 2020 12:24 am
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 21
Views: 3573

Re: SNES Doom development, Randy Linden

That's what you get when you design a RISC chip with single-word instructions and an 8-bit bus. That just isn't enough bits for all the instructions that you'd want to pack with even one 4-bit register name, never mind two or three. (There's also the fact that it was somewhat specialized for drawing...
by 93143
Fri Jun 05, 2020 7:52 pm
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 21
Views: 3573

Re: SNES Doom development, Randy Linden

I'm pretty sure the 5/3 buffering he's talking about is in SNES VRAM. It saves space versus full double buffering, thereby allowing the gun and status bar graphics to also fit. Now that I think about it, the cartridge Doom used reportedly only had 64 KB of GPRAM. That being the case, game state cou...
by 93143
Fri Jun 05, 2020 2:37 am
Forum: General Stuff
Topic: Digital Foundry Retro Doom port comparison
Replies: 41
Views: 9711

Re: Digital Foundry Retro Doom port comparison

I've just been reading the Doom Black Book, and there's an anecdote in there about Wolfenstein 3D for SNES. Apparently the subcontractor completely failed to deliver, so id had to stop in the middle of Doom development and rush the port out in a month starting from nothing. They couldn't get the ray...
by 93143
Thu May 28, 2020 5:32 pm
Forum: SNESdev
Topic: Writing to VRAM during HBlank
Replies: 12
Views: 2609

Re: Writing to VRAM during HBlank

Well, we know for certain that it can handle the voiceover in N-Warp Daisakusen... I think it's probably good for 32 kHz mono, and I suspect if you pushed it you could do 22 kHz stereo on NTSC and maybe PAL, but I haven't delved into the details of how his scheme is handled by the rest of the code (...
by 93143
Thu May 28, 2020 3:38 pm
Forum: SNESdev
Topic: Writing to VRAM during HBlank
Replies: 12
Views: 2609

Re: Writing to VRAM during HBlank

Yeah, BRR is difficult to further compress, but I think BRR compression by itself is enough of an improvement from raw uncompressed PCM in my eyes. It absolutely is. And I'm not arguing against its use. I'm just clarifying that the compression ratio is known. However, it does entail a potentially s...
by 93143
Wed May 27, 2020 11:46 pm
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 21
Views: 3573

Re: SNES Doom development, Randy Linden

I re-read coto's earlier post, and it gave me an idea. If it turns out that the wall drawing code is in fact heavily bottlenecked by pixel cache stall (as I suspect), and drawing four or more wall columns at a time is too complicated to fit in the register set (as I suspect), it might actually be re...
by 93143
Tue May 26, 2020 12:36 am
Forum: General Stuff
Topic: SNES Doom development, Randy Linden
Replies: 21
Views: 3573

Re: SNES Doom development, Randy Linden

Not in hardware. The whole PLOT arrangement was designed exclusively for CHR bitplane graphics. And even if it hadn't been, Mode 7 is a tiled bytemap format, so there would be no access penalty for any particular drawing pattern - just write the byte (or not) and you're done. You could draw in Mode ...