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Harry Potter

Z26 emulator too fast!

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5 hours ago, DeafAtariFromKansas said:

@Harry Potter

@Wizzard How fast or slow you can play these games

 

Options > Emulation. Adjust emulation speed between 0 and 1000% (The default is 100%)

 

Hope it helps..

this will not help, either not solve the sound issue.

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WRT the SDL/window manager issue, note the bullet point from the R77 webpage:

  • SDL1 has been replaced with a version of SDL2 that has been patched to support hardware acceleration on Mali / framebuffer

In particular, note the commits that start on Feb. 9, 2019 here: https://github.com/DirtyHairy/SDL/commits/8ae8d74a4569171634316304672980d07f756351

 

We essentially have a Mali port of SDL2 that talks directly to the device, bypassing the window manager completely.

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The biggest performance gain on the R77 was PGO (profile guided) optimization, easily a 10% - 20% performance gain iirc. If you want to max out the speed of Stella on your devices, do a custom build and use PGO to optimize it. Apart of that, hardware acceleration in SDL2 is a crucial difference. I don't think X or direct FB access makes much of a difference, though. You can try disabling all unnecessary daemons though to get predictive performance without context switches. There are also some defines that can be toggled in order to enable a bunch of unsafe optimizations, especially for ARM games --- those will give you another 10% or so for these.

 

If you want to dig into this for real check out the R77 firmware at https://github.com/DirtyHairy/r77-firmware-ng and take a look at the part of the build process that relates to Stella.

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I checked the release info for Stella and found out that 6.0 version is the first with cycle exact sound.

I found out that I may build older version myself and try more versions to find the best. I built 6.5.3, it is not perfect, then I tried 6.0 and it is much better, although not perfect, the sound is still sometimes different from real hardware. May try other and will see which is the best for my RK3288 Chromebook with Linux.

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5 hours ago, Wizzard said:

I built 6.5.3, it is not perfect, then I tried 6.0 and it is much better, although not perfect, the sound is still sometimes different from real hardware. 

There is no change in the sound code between 6.0 and 6.3.3, so there cannot be any difference. Except your settings differ.

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Seems there is some change, maybe not in sound, but other things, the graphics also is slower in 6.5.3. I use the same settings, tried OpenGL, ES and Software rendering, there is not so many things to set up.

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If your CPU is that much on the edge that you notice minor differences in speed, then you probably will have more problems with future releases. We have to concentrate our limited resources on mainstream platforms. So eventually older platforms may not work anymore.

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I tried 5.1.3 version and sound is much better, so this may be the version to use.

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On 7/29/2021 at 10:47 PM, Thomas Jentzsch said:

If your CPU is that much on the edge that you notice minor differences in speed, then you probably will have more problems with future releases. We have to concentrate our limited resources on mainstream platforms. So eventually older platforms may not work anymore.

Of course, you are right. This Chromebook I am using is just for playing, so it is not like it is necessary to optimize latest Stella for older hardware.

This is why I am trying various versions for older hardware like this. I found out that Stella 5.0 is even better than 5.1.3, cause it is fast and the games are without artifacts (some PAL games with odd number of lines were monochrome in later versions).

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58 minutes ago, Wizzard said:

some PAL games with odd number of lines were monochrome in later versions

You must have enabled the developer setting "PAL color loss" then.

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Not really, that option is not present in 5.1.3, but it is in 5.0, where I have it disabled and colors are OK.

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45 minutes ago, Wizzard said:

Not really, that option is not present in 5.1.3, but it is in 5.0, where I have it disabled and colors are OK.

Of course it is present in 5.1.3 too:

image.png.1f7c459deba7888e10ca54433d9d87a0.png

 

 

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I see, you are right, but it seems like it does not work. I disabled it and still have some PAL games with odd lines monochome

 

Screenshot_20210731_141439.png

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PAL color loss is only active when you play a game in PAL mode.

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Posted (edited)

Yes, it is a PAL game, of course.

Or am I missing something?

Screenshot_20210731_152302.png

Edited by Wizzard

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Hm, that's odd. 

 

Anyway, that's 5.1.3. Maybe a not reported bug. Now its too late to fix.

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That is absolutely OK, no need to fix that old version. It is just fun and interesting experience for me exploring the features in Stella version history. It is a great software.

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Well, you could simply read the Changes.txt file instead. :) 

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yes, but just reading I would not know how it runs on my playing chromebook :)

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