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TapamN

Re:Dolly Parton has died on Tuesday August 25, 2026 @04:35PM (#49440241)
Fun fact: Dolly, the cloned sheep, was named after Dolly Parton. The sheep was cloned from a mammary gland cell, so...
I bought 32GB of DDR4 SODIMMs (16GBx2 Corsair 3200MHz) April last year for $50.
Re:STV: A full-motion video codec for the Atari ST on Friday August 07, 2026 @06:32AM (#49208340)
There's a FMV player for the 8-bit Sega Master System ( https://github.com/bravesoftdz/tiler ,) which compresses to a fixed number of dynamically updated tiles. The codec in TFA and Tiler seem very similar, with Tiler also taking advantage of the SMS's ability to flip tiles horizontally or vertically.

A higher spec version of Tiler is available as TileMotion, which has a JavaScript demo decoding 1080p video in software here: https://gligli.github.io/tilemotion/demo/

Re:A whole boss fight in 256 bytes on Wednesday April 08, 2026 @04:18AM (#47687013)
Well, it's "256 bytes of x86" (plus X KB of VESA bios) (plus Y KB of FM synth patches) (plus Z KB of microcode) (plus...)
Re:Building an FPGA 3dfx Voodoo with Modern RTL Tools on Sunday March 22, 2026 @04:03PM (#47481538)
Oof. The gamma on that screenshot.

If you want to see what it's supposed to look like, copy the screenshot into GIMP, go into "Color, Levels" and in the "Input Levels" section, there should be a textbox+spinner with a "1.00". Set that to 0.45.

Re:Unicorn Jelly on Saturday February 14, 2026 @04:36PM (#47018630)
Ad blockers typically have an option to select something to disable, like a single image URL.
Re:.Beat Swatch Internet Time on Tuesday February 10, 2026 @06:26AM (#46958273)
The Sega Dreamcast online RPG "Phantasy Star Online" displayed the current time in beats.
Re:Building a 24-bit arcade CRT display adapter from scratch on Wednesday February 04, 2026 @06:25PM (#46893402)
The Galaksija computer used it's Z80 to help generate the video signal. I'm not sure how its implementation compares to your link.

https://en.wikipedia.org/wiki/Galaksija_(computer)

https://media.ccc.de/v/29c3-5178-en-the_ultimate_galaksija_t...

Re:Termux on Monday February 02, 2026 @02:18PM (#46859997)
What I use for my phone (Planet Computer Astro Slide) has a Psion 5-style physical keyboard built in.
Re:Neko: History of a Software Pet (2022) on Friday January 23, 2026 @04:44PM (#46738353)
As a kid, I remember the Windows version from being included on the disk that came with the book, "Windows Magic Tricks," published by Sybex.

Years later, I was surprised to see the exact same cat on a "port" to the Sega Dreamcast VMU (a memory card that can function as a stand-alone device, with a 48x32 pixel screen,) where pressing a button would play one of the animations. It makes a little more sense now, finding out that the cat images were released into the public domain.

Re:XBMC 4.0 for the Original Xbox on Friday November 21, 2025 @11:33PM (#46012122)
Wow, you're not kidding saying that it's cursed. I thought it would adapt a socket to the BGA pads, but it looks like the pins of the replacement CPU just sit naked on the interposer.

https://www.vogons.org/viewtopic.php?t=95704

Re:My Deus Ex lipsyncing fix mod on Friday September 26, 2025 @07:35PM (#45392127)
Weird coincidence, but I had to look through some old files backed up from the computer I was using 15+ years ago, and noticed it had C:\DeusEx sitting right there, with the SDK files in it. I found the function that handles damage in it.

https://pastebin.com/bwjaiDj7

It looks like I misremembered/misinterpreted some stuff. It looks like the top of the head behaves like the sides of the head, extending upward, forming a + shape.

Judging by how the arm/leg damage works, it the collision hit zones rotate with the enemy. Offset appears to be were the collision point is releative to the character's rotation, since it's also used to determine front/back and left/right collision. So for a hit to count as a headshot, it has to hit a cardinal octant of the collision cylinder.

Edit:

Updated diagram: https://imgur.com/a/Mec7HGm

Re:My Deus Ex lipsyncing fix mod on Friday September 26, 2025 @01:37AM (#45383043)
The headshot collision code in DX is broken as well. This is from memory from looking at the DX SDK years ago (+15 at least), but...

The collision shape used for a character in DX is a single cylinder. The game looks at where on the cylinder the collision point of the shot is, and tries to figure out if it's a head, body, or leg shot. It does this by checking how high the collision point is, with the lower X% being legs, top Y% being the head, and the middle being the body.

If a shot hits the head section, it runs some additional checks, and can sometimes still count as a body hit. There was some weird code that, after you stared at it long enough, looks like it ended up splitting the head area into compass aligned 1/8ths (so north, north-east, east, etc) and hits to the N-E-S-W octants would count as a head shot, and a hit to the NE-NW-SE-SW octants would count as body shots. (I couldn't tell if the angles rotate with the character, or are absolute relative to the world.) I think there was also a check for hits on the top cap of the cylinder, so that the hit would have to be close to the center of the cylinder to count as head hit, and near the outer rim would count as a body hit.

Hm, I should just make a diagram. Here: https://imgur.com/a/KG6MF1k

I guess what they were trying to do was make the actual head hitbox a smaller section of the head level, so that a shot that should go over the shoulder and miss would just count as a body shot and not a true headshot. And if you made a test map, with the player and a static test enemy placed in a line, this could work reliably from a fixed position. But when you actually play DX, and approach enemies from various angles, headshots inexplicably fail.

I created a (currently not publicly released) driver for the 1998 Sega Dreamcast's video hardware from scratch. It supports additional features over the driver in the open source homebrew OS, KallistiOS (KOS), like better render-to-texture support (the KOS driver only supports rendering to framebuffer sized textures), tile multipass (which allows for accumulation buffer style effects or soft shadows), and dynamically toggling anti-aliasing on the fly (with KOS it's fixed after init). Some screenshots of my driver can do are here: https://imgur.com/a/DyaqzZD

I used publicly available documentation (like https://www.ludd.ltu.se/~jlo/dc/ and the now defunct dcdev Yahoo Group), looked at the existing open source KOS driver, and looked at the source for Dreamcast emulators to figure out how things worked.

The GPU in the Dreamcast is a bit more complicated than PSX/PS2/GC since it doesn't accept polygons and draw them directly to the framebuffer. It's a tile-based deferred renderer, like many mobile GPUs, so it instead writes the polygons to a buffer in video RAM, then later walks through the polygons and renders the scene in tiles to an on-chip 32x32 pixel buffer, which finally gets written to RAM once.

This allows the Dreamcast to have a depth-only fillrate close to the 360 and PS3 (DC is 3.2 GPix/s vs 360/PS3 4.0 GPix/s), and it basically preforms a depth-only prepass to avoid doing texture reads for obscured texels. It can also preform per-pixel transparency sorting (order-independent transparency) with effectively no limit to the number of overlapping pixels (but the sorter is O(n^2), so a lot of overlap can become very expensive).

To get a working driver for the Dreamcast, you have to set up some structures in video RAM so that the hardware knows what polygons are in what tile. Another thing the driver needs to do is coordinate the part of the hardware that takes polygon commands and writes them to video RAM, and the part that actually does rendering. You typically double buffer the polygons, so that while the hardware is rendering one frame, user code can submit polygons in parallel for the next frame to another buffer.

My driver started as just code in "int main()" to get stuff on the screen, then I gradually separated stuff out from that into a real driver.

Re:Optimizing our way through Metroid on Sunday August 24, 2025 @10:37PM (#45009671)
Oh, yeah, I am. I forgot about that setting. Switching Standard allows the videos to work for me, while Privacy Badger and uBlock Origin are enabled.
Re:Optimizing our way through Metroid on Sunday August 24, 2025 @03:03AM (#45002015)
I'm using Firefox 139.0.4 canonical-002 Snap on Xubuntu, and the videos don't play for me. Even when not using private browsing, even when I disable uBlock Origin, even when I disable Privacy Badger (and, of course, I've set NoScript to enable JS for the tab.)
Re:I bought a £16 smartwatch just because it used USB-C on Saturday August 09, 2025 @02:21AM (#44844453)
Just a week? I have a USB smartwatch with a 1 year battery life, the Timex Data Link USB.
Re:A Fast, Growable Array with Stable Pointers in C on Wednesday August 06, 2025 @03:38PM (#44816685)
It not necessarily physical RAM. If you memmap large files, like maybe a large file from RAID or network share, you could still need that much virtual address space.
Re:<Blink> and <Marquee> (2020) on Sunday June 08, 2025 @02:18AM (#44214949)
My favorite trick with <marquee> was to nest them, with different, alternating directions. You could make the contents alternate between scrolling and stopping by setting the inner marquee to travel in the opposite direction at the same speed as the outer marquee. Or do more levels with alternating speeds to make it zip around randomly. I think you had to set a max width for the inner marquees for this to work?
Re:Human on Thursday May 15, 2025 @07:29AM (#43993901)
IIRC, Gödel, Escher, Bach discusses comparing chromosome/protein generation and computation.
Some of it, but I'd rather use real hardware.
Shenmue is one of my favorite games. I did a bunch of Ghidra reversing on the Dreamcast version last year, since I wanted to add improvements to it. Like adding bilinear filtering on the sky background, making time run a bit (faster so you can see time specific events like Christmas/New Year more easily,) getting the game to run without disc swapping on an ODE, and adding antialiasing (which would require mipmaps to improve rendering performance, which would require higher texture compression levels to get them to fit, which would require a different texture format that supports that...) I never got around to actually implementing any of that, outside of doing some experiments, like forcing bilinear on all 2D elements.

I don't think I found the sun/moon code (or more likely I did, but didn't realize what exactly it was doing, Ghidra SH4 has serious problems with floating point instructions making following anything that uses them almost impossible) but I did find most of the other time related code for updating the clock/calendar.

One weird thing I found while doing that is about the in-game watch. You always have a watch in your inventory, so you'd think it would be hard coded in, but it's treated like any other item. The game also has code to check if the watch is missing and add it back in anyways. But the code that draws the on-screen clock also checks if you don't have the watch, and won't draw the clock if you don't have it (or at least part of the UI clock logic is disabled, I haven't actually tried seeing what happens if you don't have a watch to verify if my interpretation is correct).

On the PAL version, the code that checks for a missing watch is at 0x0c180dc6 (that's where the code is loaded into memory, subtract 0xc010000 to get the address in 1ST_READ.BIN), and I think the code for drawing the clock (or at maybe it was just updating the hands of the clock?) is at 0x0c18290a.

Dreamcast Shenmue has code to support other video modes, like alternate resolutions (320x240p!), antialiasing, and 24/32 bit color. They're a bit bugged, like when using antialiasing, the 2D elements being squashed into the left half of the screen, and some strange issue with the screen position for the RAMDAC being setting incorrectly, causing the screen to vibrate left/right by a pixel or two, but the 3D models were drawn correctly.

24-bit color worked surprisingly well (even if the flag intended to enable it didn't seem to work, and I had to force it elsewhere.) I would have thought that having less video RAM free would have caused serious problems, but the game just loaded fewer NPCs. It was strange playing without dithering.

It seems like it should be possible to do the X async method without tearing.

When updating the cursor position, check if line being output overlaps with the cursor. If it isn't, it's safe to update the hardware cursor immediately, without tearing. Otherwise, defer updating the cursor until later (vblank would work) to avoid tearing.

Of course, this assumes it's possible to read what row of the frame buffer is being displayed. I think most hardware would support it, but I could see driver support being poorly tested, or possibly even missing entirely from Linux's video APIs.

Does Ken Shirriff have time to look at a 68030?
Re:It's time to make computing personal again on Sunday January 19, 2025 @09:03PM (#42764232)
In 1992, you more options. Your friends could tell you for free, you could stumble on them yourself, or you could get them with a magazine or book (which you didn't necessarily have to buy, you could just flip through it at the store and memorize the cheats.)
Re:The GTA III port for the Dreamcast has been released on Tuesday December 31, 2024 @06:16PM (#42562592)
I figured out how to fix Hydro Thunder's compatibility issues last year (it would very briefly change the pixel clock). You can either use a Codebreaker code to fix the game if you're running from a real disc, or if you use an ODE, you can patch the disc image.

https://www.dreamcast-talk.com/forum/viewtopic.php?f=5&t=165...

Re:Into CPS, Never to Return on Wednesday December 25, 2024 @05:35PM (#42511647)
I was hoping, but not expecting, for it to be about the Capcom arcade board.
Re:Lou's Pseudo 3D Page (2013) on Wednesday December 18, 2024 @03:09PM (#42454503)
Also on the Sega Genesis/MegaDrive as F1 World Championship, and a sequel, Kawasaki Superbike Challenge.
Re:1/0 = 0 (2018) on Monday December 02, 2024 @07:24AM (#42295505)
True correct behavior would have that if a > b, then a + c > b + c also holds true for all integers, but that isn't guaranteed for wrapping (or clamping.) (e.g. if 250 > 1, then 250 + 10 > 1 + 10 should be true, but with 8-bit wrapping you would get 4 > 11, which is false.)

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