Shash's Emu Dev WIP

[Grzeslav]

November 18, 2007 - Texture fix and icon viewer

Yesterday I was rather bored for a few hours (even if I've a lot of real life stuff to do...), so after checking some information from the DS cartridge header (for some unrelated work still to be done), I thought how hard it'd be to add an icon viewer to the "Game Info" dialog. Extracting it from the header wasn't that hard, as the format is quite simple: a 32x32 pixels icon, stored on a 8x8 tile basis, 4bits per pixel, which are used to lookup on a fixed 16 colour palette (per icon).

In fact, converting the icon was easy, but I had major problems due to some recent changes, as I forgot I needed to use GDI+ to draw stuff on dialogs, rather than using plain GDI (that's what all desmume uses on the windows port). When I moved the drawing code of the icon to GDI+, it worked perfectly. I deleted all the MAP/OAM/etc viewers that relied on GDI code, as I plan to rewrite the GUI in the near future anyway, so there's no point in fixing that code.

After that, I wanted to finally fix the last bits of Mario&Luigi to look perfect. A few weeks ago, I cared to make it run where it "freezed" in the past: in fact, it didn't freeze, just took ages to render a new frame, due to a rather important bug in the 3D core. The main problem after that, is that ALL textures looked wrong: for example, where Koopa should be, only textures of arrows were shown.

When approaching the problem, I had only a stupid idea of what could be: due to the way the display lists are handled, there was a slight chance that the texture bind before drawing the polygons was done in wrong order. Well, to make a long story short, I was wrong: I tried changing a few bits, even hacking some stuff, and it didn't fix anything. In fact, the fix was easier and more logical.

I've been coding on PC for quite a few years, and I'm quite used to some stuff working in a certain way. While emulating the 3D core of the DS, I've already fallen on that problem quite a few times: on the DS, setting attributes per polygon (without starting a "primitive block") isn't that rare, for example, transformations (scaling, for example :P). In this case, it was the texture changing while the primitive block was open. I guess that, if you want to draw all the stuff onscreen, and you only use one type of primitive (a quad, for example), then changing the texture within the primitive block isn't that rare.

Anyway, adding the ability to change textures within a primitive block fixed "Mario&Luigi: Partners in time" and "Final Fantasy XII: Revenant Wings", so now both seem to be 100% playable and glitch free (and run rather fast). The usual screenshots:

shash's Emu Dev

[shashClp]

You could have, at least, linked to the source :P

[susanomon]

Sorry for asking but when will you give a release???
all this your are showing with screenshot are very promising

[shashClp]

Originally Posted by susanomon

Sorry for asking but when will you give a release???
all this your are showing with screenshot are very promising

Whenever it's done :P

[kuro]

I wonder how Shash's work treats Advance Wars: Dual Strike. So far, no author's been successful at running that game. D:

However, seeing how well a lot of these shots are for games much more complicated than AWDS, I guess there's hope!

AWDS is the only game I have, so when I see a new version of a DS emu come out, I check it out. So far, neither ideas or desmume run it any better than it ran 6 months ago. No$GBA's latest version actually makes it run 10x worse. I'm gonna guess that the devs don't even have access to this game, since I'm the only one here who even seems to play Advance Wars to begin with.

Anyhew, can't wait till this gets released! I'm sure it'll give me the best AWDS results I've been waiting for.

[MasterPhW]

Originally Posted by kuro

Anyhew, can't wait till this gets released! I'm sure it'll give me the best AWDS results I've been waiting for.

Sorry to disappoint you, but it won't be released afaik, because shash is working on it's own desmume version, just for his coding fun and there's nothing or noone he is owe anything, so you probably will never see a desmume version with all these fixes included.

[shashClp]

MasterPHW: that's true, but also I commit stuff on the official version from time to time, so the public version gets some stuff, mainly those that are asked by homebrew developers. It's the only thing that really motivates me enough to make some of my code public.

[ShakirMole]

nice work dude... I still hope that someday your release and that of the latest emus have same compatibility

[MasterPhW]

Originally Posted by shashClp

MasterPHW: that's true, but also I commit stuff on the official version from time to time, so the public version gets some stuff, mainly those that are asked by homebrew developers. It's the only thing that really motivates me enough to make some of my code public.

Oh yeah, seen it, after looking at the source and the changelog, sorry for the missinformation I was spreading. I really like your blog, it's written great and has a lot of good informations!
I also really like your work, keep it coming! Nice work and I hope you won't lost motivation.

[dreampeppers99]

shashClp just one word "good work" (actually two).
Your blog is one of the best (maybe the best) to person that wanted dev or see how the process of dev an emulator goes....
The Best new I've receive "Mario&Luigui" "FF13" works 100%.

[mbroker]

Originally Posted by shashClp

You could have, at least, linked to the source :P

Then you should have posted first to make sure.