I'm one of the coders who worked on the Overdrive 2 demo (although not on the reverse engineering that resulted in this document). We're going to release more follow-ups about the development of the demo.<p>I'm currently working on a write-up of the polygon to tile drawing routine used for the fullscreen 3D scenes.<p>I'm not sure about the time frame yet, but they will be posted at <a href="http://www.pouet.net/prod.php?which=69648" rel="nofollow">http://www.pouet.net/prod.php?which=69648</a> and/or <a href="http://www.pouet.net/topic.php?which=11035" rel="nofollow">http://www.pouet.net/topic.php?which=11035</a>.
Context from ShonumiGBE+ at /r/emulation :<p>Might help to explain some context for people who don't know what Overdrive 2 is, or why it's important.<p>TiTAN is a pretty prominent group in the demo scene. They do a lot of crazy demos, basically coding consoles to their limit while making cool audio-visual presentations. Overdrive 2 is the follow up to the original Overdrive demo[1], and once again TiTAN have pulled off a bunch of insane effects on the Mega Drive.<p>Overdrive 2 is relevant to /r/emulation because it can't be emulated (yet). From what I understand, it's doing a bunch of tricks (described in the write-up on Google Docs) that emulators currently can't handle. That's right, even in 2017, Genesis/MD emulation has a ways to go, which is kind of exciting to me. I'd love to see emulators like Blastem, Exodus, and higan step up to the plate. Then maybe the demo scene can come up with even more torture tests ;)<p>Anyway, you guys can catch Overdrive 2 over on YouTube.[2] This stuff is sick.<p>[1] <a href="http://www.pouet.net/prod.php?which=61724" rel="nofollow">http://www.pouet.net/prod.php?which=61724</a><p>[2] <a href="https://www.youtube.com/watch?v=OeGdJk5zb6c" rel="nofollow">https://www.youtube.com/watch?v=OeGdJk5zb6c</a>
What a fantastic demo! Thanks for sharing your in-depth notes about reverse-engineering the hardware's behavior.<p>I admit, previously I didn't understand why some emulators promoted so heavily the fact that they did more hardware-accurate emulation.<p>My relationship with old consoles is one of casual nostalgia, and a crash-free experience was all I asked for, one devoid of glaring visual glitches or inopportune jerkiness as you're being attacked by a boss.<p>That's a decent goal too, but just like the demoscene attempts to push the hardware and software to the ultimate edge of the envelope, I now better appreciate the developers who have taken extra care to mimic the exact operating quirks of the original. Resources like these help build the body of knowledge for new and existing developers, and help raise the bar of what the community desires as well.
Love it! I've written a hopefully accurate Genesis emulator (<a href="https://github.com/rasky/genemu" rel="nofollow">https://github.com/rasky/genemu</a>) and Overdrive is one of the holy grails of perfect emulation :)
This is a phenomenal demo.<p>Do the 3D bits implement the additional SVP chip used in (AFAIK only) Virtua Racing?<p>I used to do some interesting stuff with the MD / Genesis back in the day (like when I was 10-12 years old) - first with ROM hacking and moving into small bits of 68k ASM before getting into GBA and DS homebrew development, which was loads of fun (especially with an R4! screw commercial ROMs, this was a dream come true for me for homebrew! :D)<p>I was really involved in the Sonic Homebrew and fangaming scene and ended up sticking around on Sonic Retro (formerly SWS2B) since 2001 but haven't been active in ages...this makes me miss it! (I mostly do VR stuff these days :3)