Vertical tilt is rather strange. It changes the screen resolution to get the effect. This makes dosbox reset the window and video mode so it probably also looses the pressed keys...

Hmm, that probably means there is no fix for it, is there?

BTW, when I still had win98, I could play psycho pinball on this monitor, including the vertical tilt. It didn't modeswitch or whatever (which is notable by a blackout), and if I remember correctly, even a change in screen position would result in the monitor having to resync to the changed frequencies. Add to this that the tilt effect is animated, meaning it would require about 10-25 (or so) changes in video timings, it seems somewhat unlikely. Are you sure this is what happens?

I'm not sure what happens, but this is what I observed. I did a lot of testing with Psycho pinball when debugging my D3D patch and one of the strange things was that vertical tilt was extremely slow. Then I noticed that the resolution is changing and the textures are being recreated. But I don't know the details of VGA hardware to know what exactly the game is doing...

Yep, the game is changing resolution (I tested only High resolution setting) from 320x367 to 320x355 I think in steps of 1 e.g. 320x366 320x365 or something like that, anyway the way to fix it is to keep the height at 367 if resolution changes to anything between 320x367 and 320x355 I have done this by changing vga_draw.cpp of DOSBox 0.65 by adding this piece of code:

if (height <= 367 && height > 354) {
height = 367;
scalew = 1;
scaleh = 1;
}

at line 650 before vga.draw.lines_total=height;

Also note that this can potentially mess up any other game that uses that resolution. There is one thing, I tried this only with DOSBox 0.60 because I can't get any later version to compile with MSVC 6 and I'm to lazy to download and install MinGW and MSYS, but it should work with newer versions. And some part of the credit should go to felipe.sanches who posted resolution patch for Pinball Fantasies from which I got the idea for Psycho Pinball.

In 0.65, it's line 645.

The variables scalew and scaleh are not defined anymore. I commented them out, and the patch still works. I also wouldn't know why you'd wanna override the scaling.

When tilting now, you can see the top of the table at the bottom 😀

Perhaps this patch can be extended so that it checks for the presence of psycho pinball in memory. A dirty hack would be to check if the executable name is _P_.EXE. This was (and perhaps is) a trick done by a lot of graphics drivers, which employ game specific cheats to improve framerates. Changing the name of some game to unrealtournament.exe radicly changed speed 😀

BTW, in-game screenshots of psycho pinball are in 640x367. Where does that 320 come from?

The pixels are streched so without horizontal scaling you get 320x367. 😎
I looked in 0.65 sources, it's doublewidth=true; for some resolutions.

Perhaps that's why my ball looks like an american football. Also, in DOS, the screen was much more narrow; it wasn't filled horizontally.

How does one accomplish correct geometry in Dosbox with psycho pinball?

Instead of scalew = 1; put doublewidth=false; this should fix streching. Looks like this is one of the things changed between 0.60 and 0.65. 😎

Haha, the table looks very weird like this, but I guess it's correct 😀. It does however, also decrease in vertical size now.

Is there is no way to do it by tweaking the config file? And, shouldn't this doublewidth issue be solved in general? I mean, would dosbox be able to detect that it shouldn't be stretched? If psycho asks for 320x367, why does it set it to 640x376?

I wouldn't know. When I get and set MinGW up and runnig I will look into it. As for Psycho Pinball it could be that it is infact asking for 640x376 and stretches table horizontaly.

BTW, what I said about it not filling the screen vertically, I didn't remember correctly that normally, it doesn't do this either. So, there is no problem there.

if we use the .exe filename as reference, the patch wont work for renamed files. Thats not a big problem, but its not elegant, either. So I tryied to figure out another solution.

We could try to search for signatures of the respective games in know emulated memory positions. Thats idea is similar to simple virus detection algorithms. Indeed, its not enough to rename a virus file because the antivirus continues to detect it 😀

About merging the patches, I dont see why we should do that. They provide separete effects: no-scroll patch gives us fulltable and the tilt patch corrects (in a hacky way) what seems to be a real bug. I think they should be kept separate for now.

Off course, in the future we can integrate various pinball related hacks such as these in a big pinball enhancement pack for dosbox 😁

We could try to search for signatures of the respective games in know emulated memory positions. Thats idea is similar to simple virus detection algorithms. Indeed, its not enough to rename a virus file because the antivirus continues to detect it

That would require making signatures/hashes of all known versions of the program. I don't know if dosbox would easily support detecting signatures, but it does sound like a good solution.

About merging the patches, I dont see why we should do that. They provide separete effects: no-scroll patch gives us fulltable and the tilt patch corrects (in a hacky way) what seems to be a real bug. I think they should be kept separate for now.

You're right, the tilt issue is actually a real bug. I didn't really see it as a dosbox bug because I'm not sure though if the developers apply such game specific fixes.

Both patches do have to be modified to be able to work along side eachother, though, because they are mutually exclusive now.

BTW, does this bugreport and patch have to be submitted to the tracker, or is the existence here enough?

I suggest that you report the bug properly.

What else would you suggest for pinball enhancement?

I thought about faking multiball but it seems to be too hard to do. But not impossible. When we are playing between the software and the hardware that it expects to be running on, we can trick it with a lot of flexibility. We can build a middle layer on top of the original hardware.

Let me tell you about some of the other tricks that i've been doing with pinball fantasies (maybe it works with other pinball games too)

I have successfully integrated dosbox with a set of LEDs on my parallel port. Then I sincronized the flashing of the LEDs with the flashing of some of the playfield lights. I got it sincronized with the P A R T Y lights for example.

game specific FIXES are allright. (If they are fixes and the real hardware acted that way as well)
Game specific HACKS won't go into the official code.

OK, I'll make a bug report about the tilt issue.

The hacks issue we'd better suggest in the other thread. So, let me continue in the other thread.

halfgaar wrote:

In 0.65, it's line 645. […]
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In 0.65, it's line 645.

The variables scalew and scaleh are not defined anymore. I commented them out, and the patch still works. I also wouldn't know why you'd wanna override the scaling.

When tilting now, you can see the top of the table at the bottom 😀

Perhaps this patch can be extended so that it checks for the presence of psycho pinball in memory. A dirty hack would be to check if the executable name is _P_.EXE. This was (and perhaps is) a trick done by a lot of graphics drivers, which employ game specific cheats to improve framerates. Changing the name of some game to unrealtournament.exe radicly changed speed 😀

BTW, in-game screenshots of psycho pinball are in 640x367. Where does that 320 come from?

sorry for bumping this thread but im having the same issue here, when i press shift (the flipper) together with space (the tilt) the game shuts down... where is this vga_draw.cpp file where i can put those lines of code in? In folder options i enabled show invisible files but i cant find it anywhere.

You need the source for this (you can download it). You will also need a C(++) compiler. But judging by your question, I think you will have trouble setting that up, it's kind of complicated.

You could also arrange someone to make a custom build for you. I don't have Windows, so I can't help you.

The bug about this issue has been filed BTW.