BizHawk
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TASEmulators
[Core Port Req.] BlastEm (Sega MD/Genesis)
a feature request, and not replace but offer as well
blastem_libretro waterbox? blastem_libretro.dll feature request? ALT core?
The upstream core appears to be broken. Loading any savestate is the core's weak point and might crash BizHawk, so BlastEm core needs to be updated and fixed if developers want to add it here. Even if it doesn't crash, it would cause timing issues, effectively desyncing a TAS. Even most hacked ROMs crash it too... Waterboxing is the only way to avoid this.
It crashes most likely because it is a very new core. This issue only exists in the Libretro release of BlastEm.
Right, but my only reason for requesting it is hearing how much more accurate than the current core it is however if its prone to crashing I made a mistake requesting it
For those out of the loop:
BlastEm is an open source, higly accurate emulator for the Genesis/Megadrive that runs on modest hardware. It is the first emulator to properly run Titan's impressive Overdrive 2 demo and it is the only other emulator besides Genesis Plus GX that can properly run the original Overdrive.
It's written in C with the usual SDL2. The source is on a self-hosted Mercurial repo and is licensed under the GPL v3+.
While it has many issues that crashes often (including savestates), it might be good idea but BizHawk devs need to fix these or the core will be completely unusable.
I was just thinking a stable core option would be a nice addition. Dont know how stable this is though if its truly prone to crashing
It is pretty stable if we don't use savestates. Both native and gst savestate formats doesn't function correctly at all. Waterbox requried.
This core appears to be broken. Loading any savestate is the core's weak point and might crash BizHawk
Ok so waterbox it.
I thought it might give bizhawk a more accurate genesis core. If blastem is really that buggy i dont think its worth adding
Aside from elaborate technical demos, which games does blastem emulate better than upstream gpgx?
Ah, when I copy-pasted that description from the website, I didn't notice the word "demo". BlastEm is actually missing a lot of mappers and peripherals so there would be little benefit in adding it as an alternate core, unless it offered a substantial speed increase over GPGX in those games it does emulate.
I belive the newest blastem 0.63 can run the full library. Its slower than genplgx but more accurate. That being said i dont think its stable enough. Too many ppl say it crashed. Using myself the win64 nightly no issues but when i tried the liberto version crash crash crash. So i cancel my request.
It is still a good idea, since it perfectly runs TiTAN Overdrive 2 Demo.
It is still a good idea, since it perfectly runs TiTAN Overdrive 2 Demo.
Runs the complete commercial library without hacks….
You plan to TAS a demo?
No, but since it perfectly runs it, it means that this core is very accurate, pretty similar to hardware
You plan to TAS a demo?
No, but since it perfectly runs it, it means that this core is very accurate, pretty similar to hardware
Do what I did, switch to retroarch. Now I have both cores and sharers.
Doesn't look like a perfect core, but it'd be nice to have another Genesis in our pocket.
It has to be waterboxed, because the upstream one is unusable for TASing. Even if it would, it would cause thousands of desyncs (even worse than Octoshock). We need to check the savestate script of the upstream core why loading a savestate interferes with the game and can crash the emulator. https://github.com/libretro/blastem/blob/libretro/saves.c
Compare with Genplus-gx: https://github.com/libretro/Genesis-Plus-GX/blob/master/core/state.c
Took a peek at doing this: going off it's front page:
BlastEm depends on SDL2, GLEW and OpenGL.
~~OpenGL is an immediate no for waterboxing, that would need to be stripped out of the core, how easy that is I don't know.~~ (There's a DISABLE_OPENGL define flag in there, that flag would probably need to be set).
There is another interesting aspect to this core: it seems to support dynarec. This wouldn't work in waterbox as it is (although it could in theory be made to work), but regardless seems like a NEW_CORE define disables this dynarec? Could potentially be interesting to look into, as I imagine that dynarec might be significantly faster compared gpgx (does libretro disable dynarec / the "it's slower" due to that?).
Regardless, it still doesn't look pretty to port over, SDL2 should probably be stripped out (does wbx even support that?). But if that's not so hard then it's probably painless?
EDIT: Looks like a lot of the problems can just be disabled with specific flags anyways. Doesn't seem so bad looking even further.
https://github.com/CasualPokePlayer/BizHawk/tree/blastem/waterbox/blastem
Well, I took a stab at this. It builds. That's it. I have no idea if this even works. Probably does. Needs an actual interface and stuff c# side actually hooked up, but it doesn't seem so bad.
EDIT: Got some interface in, it boots and plays games. A lot of shit needs to be hooked up. Not too bad ig
OpenGL is an immediate no for waterboxing, that would need to be stripped out of the core, how easy that is I don't know. (There's a DISABLE_OPENGL define flag in there, that flag would probably need to be set).
Should we use LLVMpipe for this?
Also, no audio currently. Inputs do not work.
Yes because those were not hooked up. Stop complaining work in progresses are incomplete.