Commit Graph

7 Commits

Author SHA1 Message Date
Tim Allen 5df717ff2a Update to v101r12 release.
byuu says:

Changelog:

  - new md/bus/ module for bus reads/writes
      - abstracts byte/word accesses wherever possible (everything but
        RAM; forces all but I/O to word, I/O to byte)
      - holds the system RAM since that's technically not part of the
        CPU anyway
  - added md/controller and md/system/peripherals
  - added emulation of gamepads
  - added stub PSG audio output (silent) to cap the framerate at 60fps
    with audio sync enabled
  - fixed VSRAM reads for plane vertical scrolling (two bugs here: add
    instead of sub; interlave plane A/B)
  - mask nametable read offsets (can't exceed 8192-byte nametables
    apparently)
  - emulated VRAM/VSRAM/CRAM reads from VDP data port
  - fixed sprite width/height size calculations
  - added partial emulation of 40-tile per scanline limitation (enough
    to fix Sonic's title screen)
  - fixed off-by-one sprite range testing
  - fixed sprite tile indexing
  - Vblank happens at Y=224 with overscan disabled
      - unsure what happens when you toggle it between Y=224 and Y=240
        ... probably bad things
  - fixed reading of address register for ADDA, CMPA, SUBA
  - fixed sign extension for MOVEA effect address reads
  - updated MOVEM to increment the read addresses (but not writeback)
    for (aN) mode

With all of that out of the way, we finally have Sonic the Hedgehog
(fully?) playable. I played to stage 1-2 and through the special stage,
at least. EDIT: yeah, we probably need HIRQs for Labyrinth Zone.

Not much else works, of course. Most games hang waiting on the Z80, and
those that don't (like Altered Beast) are still royally screwed. Tons of
features still missing; including all of the Z80/PSG/YM2612.

A note on the perihperals this time around: the Mega Drive EXT port is
basically identical to the regular controller ports. So unlike with the
Famicom and Super Famicom, I'm inheriting the exension port from the
controller class.
2016-08-22 08:11:24 +10:00
Tim Allen 427bac3011 Update to v101r06 release.
byuu says:

I reworked the video sizing code. Ended up wasting five fucking hours
fighting GTK. When you call `gtk_widget_set_size_request`, it doesn't
actually happen then. This is kind of a big deal because when I then go
to draw onto the viewport, the actual viewport child window is still the
old size, so the image gets distorted. It recovers in a frame or so with
emulation, but if we were to put a still image on there, it would stay
distorted.

The first thought is, `while(gtk_events_pending())
gtk_main_iteration_do(false);` right after the `set_size_request`. But
nope, it tells you there's no events pending. So then you think, go
deeper, use `XPending()` instead. Same thing, GTK hasn't actually issued
the command to Xlib yet. So then you think, if the widget is realized,
just call a blocking `gtk_main_iteration`. One call does nothing, two
calls results in a deadlock on the second one ... do it before program
startup, and the main window will never appear. Great.

Oh, and it's not just the viewport. It's also the widget container area
of the windows, as well as the window itself, as well as the fullscreen
mode toggle effect. They all do this.

For the latter three, I couldn't find anything that worked, so I just
added 20ms loops of constantly calling `gtk_main_iteration_do(false)`
after each one of those things. The downside here is toggling the status
bar takes 40ms, so you'll see it and it'll feel a tiny bit sluggish.

But I can't have a 20ms wait on each widget resize, that would be
catastrophic to performance on windows with lots of widgets.

I tried hooking configure-event and size-allocate, but they were very
unreliable. So instead I ended up with a loop that waits up to a maximm
of 20ms that inspects the `widget->allocation.(width,height)` values
directly and waits for them to be what we asked for with
`set_size_request`.

There was some extreme ugliness in GTK with calling
`gtk_main_iteration_do` recursively (`hiro::Widget::setGeometry` is
called recursively), so I had to lock it to only happen on the top level
widgets (the child ones should get resized while waiting on the
top-level ones, so it should be fine in practice), and also only run it
on realized widgets.

Even still, I'm getting ~3 timeouts when opening the settings dialog in
higan, but no other windows. But, this is the best I can do for now.

And the reason for all of this pain? Yeah, updated the video code.

So the Emulator::Interface now has this:

    struct VideoSize { uint width, height; };  //or requiem for a tuple
    auto videoSize() -> VideoSize;
    auto videoSize(uint width, uint height, bool arc) -> VideoSize;

The first function, for now, is just returning the literal surface size.
I may remove this ... one thing I want to allow for is cores that send
different texture sizes based on interlace/hires/overscan/etc settings.

The second function is more interesting. Instead of having the UI trying
to figure out sizing, I figure the emulation cores can do a better job
and we can customize it per-core now. So it gets the window's width and
height, and whether the user asked for aspect correction, and then
computes the best width/height ratio possible. For now they're all just
doing multiples of a 1x scale to the UI 2x,3x,4x modes.

We still need a third function, which will probably be what I repurpose
videoSize() for: to return the 'effective' size for pixel shaders, to
then feed into ruby, to then feed into quark, to then feed into our
shaders. Since shaders use normalized coordinates for pixel fetching,
this should work out just fine. The real texture size will be exposed to
quark shaders as well, of course.

Now for the main window ... it's just hard-coded to be 640x480, 960x720,
1280x960 for now. It works nicely for some cores on some modes, not so
much for others. Work in progress I guess.

I also took the opportunity to draw the about dialog box logo on the
main window. Got a bit fancy and used the old spherical gradient and
impose functionality of nall/image on it. Very minor highlight, nothing
garish. Just something nicer than a solid black window.

If you guys want to mess around with sizes, placements, and gradient
styles/colors/shapes ... feel free. If you come up with something nicer,
do share.

That's what led to all the GTK hell ... the logo wasn't drawing right as
you resized the window. But now it is, though I am not at all happy with
the hacking I had to do.

I also had to improve the video update code as a result of this:

  - when you unload a game, it blacks out the screen
      - if you are not quitting the emulator, it'll draw the logo; if
        you are, it won't
  - when you load a game, it black out the logo

These options prevent any unsightliness from resizing the viewport with
image data on it already

I need to redraw the logo when toggling fullscreen with no game loaded
as well for Windows, it seems.
2016-08-15 14:52:05 +10:00
Tim Allen ac2d0ba1cf Update to v101r05 release.
byuu says:

Changelog:

  - 68K: fixed bug that affected BSR return address
  - VDP: added very preliminary emulation of planes A, B, W (W is
    entirely broken though)
  - VDP: added command/address stuff so you can write to VRAM, CRAM,
    VSRAM
  - VDP: added VRAM fill DMA

I would be really surprised if any commercial games showed anything at
all, so I'd probably recommend against wasting your time trying, unless
you're really bored :P

Also, I wanted to add: I am accepting patches\! So if anyone wants to
look over the 68K core for bugs, that would save me untold amounts of
time in the near future :D
2016-08-13 09:47:30 +10:00
Tim Allen 1df2549d18 Update to v101r04 release.
byuu says:

Changelog:

  - pulled the (u)intN type aliases into higan instead of leaving them
    in nall
  - added 68K LINEA, LINEF hooks for illegal instructions
  - filled the rest of the 68K lambda table with generic instance of
    ILLEGAL
  - completed the 68K disassembler effective addressing modes
      - still unsure whether I should use An to decode absolute
        addresses or not
      - pro: way easier to read where accesses are taking place
      - con: requires An to be valid; so as a disassembler it does a
        poor job
      - making it optional: too much work; ick
  - added I/O decoding for the VDP command-port registers
  - added skeleton timing to all five processor cores
  - output at 1280x480 (needed for mixed 256/320 widths; and to handle
    interlace modes)

The VDP, PSG, Z80, YM2612 are all stepping one clock at a time and
syncing; which is the pathological worst case for libco. But they also
have no logic inside of them. With all the above, I'm averaging around
250fps with just the 68K core actually functional, and the VDP doing a
dumb "draw white pixels" loop. Still way too early to tell how this
emulator is going to perform.

Also, the 320x240 mode of the Genesis means that we don't need an aspect
correction ratio. But we do need to ensure the output window is a
multiple 320x240 so that the scale values work correctly. I was
hard-coding aspect correction to stretch the window an additional \*8/7.
But that won't work anymore so ... the main higan window is now 640x480,
960x720, or 1280x960. Toggling aspect correction only changes the video
width inside the window.

It's a bit jarring ... the window is a lot wider, more black space now
for most modes. But for now, it is what it is.
2016-08-12 11:07:04 +10:00
Tim Allen 1c0ef793fe Update to v100r04 release.
byuu says:

I now have enough of three instructions implemented to get through the
first four instructions in Sonic the Hedgehog.

But they're far from complete. The very first instruction uses EA
addressing, which is similar to x86's ModRM in terms of how disgustingly
complex it is. And it also accesses Z80 control registers, which obviously
isn't going to do anything yet.

The slow speed was me being stupid again. It's not 7.6MHz per frame,
it's 7.67MHz per second. So yeah, speed is so far acceptable again. But
we'll see how things go as I keep emulating more. The 68K decode is not
pretty at all.
2016-07-12 20:19:31 +10:00
Tim Allen 76a8ecd32a Update to v100r03 release.
byuu says:

Changelog:
- moved Thread, Scheduler, Cheat functionality into emulator/ for
  all cores
- start of actual Mega Drive emulation (two 68K instructions)

I'm going to be rather terse on MD emulation, as it's too early for any
meaningful dialogue here.
2016-07-10 15:28:26 +10:00
Tim Allen 3dd1aa9c1b Update to v100r02 release.
byuu says:

Sigh ... I'm really not a good person. I'm inherently selfish.

My responsibility and obligation right now is to work on loki, and
then on the Tengai Makyou Zero translation, and then on improving the
Famicom emulation.

And yet ... it's not what I really want to do. That shouldn't matter;
I should work on my responsibilities first.

Instead, I'm going to be a greedy, self-centered asshole, and work on
what I really want to instead.

I'm really sorry, guys. I'm sure this will make a few people happy,
and probably upset even more people.

I'm also making zero guarantees that this ever gets finished. As always,
I wish I could keep these things secret, so if I fail / give up, I could
just drop it with no shame. But I would have to cut everyone out of the
WIP process completely to make it happen. So, here goes ...

This WIP adds the initial skeleton for Sega Mega Drive / Genesis
emulation. God help us.

(minor note: apparently the new extension for Mega Drive games is .md,
neat. That's what I chose for the folders too. I thought it was .smd,
so that'll be fixed in icarus for the next WIP.)

(aside: this is why I wanted to get v100 out. I didn't want this code in
a skeleton state in v100's source. Nor did I want really broken emulation,
which the first release is sure to be, tarring said release.)

...

So, basically, I've been ruminating on the legacy I want to leave behind
with higan. 3D systems are just plain out. I'm never going to support
them. They're too complex for my abilities, and they would run too slowly
with my design style. I'm not willing to compromise my design ideals. And
I would never want to play a 3D game system at native 240p/480i resolution
... but 1080p+ upscaling is not accurate, so that's a conflict I want
to avoid entirely. It's also never going to emulate computer systems
(X68K, PC-98, FM-Towns, etc) because holy shit that would completely
destroy me. It's also never going emulate arcade machines.

So I think of higan as a collection of 2D emulators for consoles
and handhelds. I've gone over every major 2D gaming system there is,
looking for ones with games I actually care about and enjoy. And I
basically have five of those systems supported already. Looking at the
remaining list, I see only three systems left that I have any interest
in whatsoever: PC-Engine, Master System, Mega Drive. Again, I'm not in
any way committing to emulating any of these, but ... if I had all of
those in higan, I think I'd be content to really, truly, finally stop
writing more emulators for the rest of my life.

And so I decided to tackle the most difficult system first. If I'm
successful, the Z80 core should cover a lot of the work on the SMS. And
the HuC6280 should land somewhere between the NES and SNES in terms of
difficulty ... closer to the NES.

The systems that just don't appeal to me at all, which I will never touch,
include, but are not limited to:
* Atari 2600/5200/7800
* Lynx
* Jaguar
* Vectrex
* Colecovision
* Commodore 64
* Neo-Geo
* Neo-Geo Pocket / Color
* Virtual Boy
* Super A'can
* 32X
* CD-i
* etc, etc, etc.

And really, even if something were mildly interesting in there ... we
have to stop. I can't scale infinitely. I'm already way past my limit,
but I'm doing this anyway. Too many cores bloats everything and kills
quality on everything. I don't want higan to become MESS v2.

I don't know what I'll do about the Famicom Disk System, PC-Engine CD,
and Mega CD. I don't think I'll be able to achieve 60fps emulating the
Mega CD, even if I tried to.

I don't know what's going to happen here with even the Mega Drive. Maybe
I'll get driven crazy with the documentation and quit. Maybe it'll end
up being too complicated and I'll quit. Maybe the emulation will end up
way too slow and I'll give up. Maybe it'll take me seven years to get
any games playable at all. Maybe Steve Snake, AamirM and Mike Pavone
will pool money to hire a hitman to come after me. Who knows.

But this is what I want to do, so ... here goes nothing.
2016-07-09 14:21:37 +10:00