Mouse pointer latency in RTG screenmodes?

[ral-clan]

Hi, FS-UAE has really gotten good since September when it automatically updated for me on my Lubuntu installation. With this update it got a LOT faster, finally matching the speed of WinUAE on the same machine.

The only thing that's not as good as WinUAE yet is that there seems to be a noticeable mouse pointer latency on RTG screens. This latency gets even more noticeable when I use a high resolution RTG screenmode like 1080 x 1920.

When I move the PC mouse in these high-res RTG modes the Amiga pointer seems to take a half-second or so to start moving. I know this doesn't sound like much time, but it actually makes a big difference and feels really wierd - like I'm moving the mouse pointer through thick syrup.

I've tried playing with the Amiga Workbench mouse settings but nothing helps. Also, when using low resolution RTG screenmodes and native chipset screenmodes there is no (or little noticable) latency. The mouse movement feels natural. It's only as I crank the screenmode resolution up in RTG modes that I notice the latency getting worse.

When I press the middle mouse button and can see both the hosting OS's mouse pointer AND the Amiga's mouse pointer at the same time you can really compare how the native OS's mouse pointer is responding instantaneously and the emulated mouse pointer takes a split second to respond.

The Amiga mouse in WinUAE, on the other hand, feels very snappy at any resolution and is always just as responsive as the native hosting OS's own mouse pointer.

I'm using the exact same Amiga configuration in FS-UAE (under Linux) and WinUAE (Windows XP), so I think it's an emulator issue rather than the way I've got my emulated Amiga setup.

Any ideas of how to reduce the latency?

I'm using Lubuntu 14.10 on an older dual core PC. I don't think the hardware is the problem though as WinUAE on the same system has a responsive mouse pointer.

[FrodeSolheim]

Hi, I'm guessing that the sluggishness could be due to problems rendering frames fast enough (that would at least explain why it gets worse with increasing resolutions).

When running FS-UAE, use Ctrl+F10 to see performance stats. The SYS number/graph is actually rendered frames per second, and EMU is emulated fps. Do either one (or both) of these numbers decrease when you are using a high-resolution mode?

[ral-clan]

Originally Posted by FrodeSolheim

Hi, I'm guessing that the sluggishness could be due to problems rendering frames fast enough (that would at least explain why it gets worse with increasing resolutions).

When running FS-UAE, use Ctrl+F10 to see performance stats. The SYS number/graph is actually rendered frames per second, and EMU is emulated fps. Do either one (or both) of these numbers decrease when you are using a high-resolution mode?

Hi Frode,

It looks like you are correct. Here are my stats with different screenmodes:

* DeluxePaint IV, 640x480 interlace:
SYS 59.4, EMU 59.4

* DirMaster 2, 800x600 RTG:
SYS 59.29, EMU 59.29

* Workbench, 1280 x 720 RTG:
SYS 38.5, EMU 59.29

* ImageFX, 1920 x 1280 RTG:
SYS 18.17, EMU 54.50

I'm using a dual core X86 CPU computer with 4GB of RAM and Lubuntu. This system can run WinUAE well under WinXP so I'm assuming it's a problem with the graphics driver under Lubuntu not being as efficient?

I've been using the motherboard Intel graphics chipset (Graphics Media Accelerator 950). There is a graphics card slot in my computer. Apparently it's a PCI express x16 slot. Lubuntu tends to be hard to configure with third party graphics cards, so I've been trying to avoid doing that. I am not sure my motherboard graphics chip would have such trouble rendering 2D frames like that. It's an older computer yes, but not ancient.

Any suggestions would be appreciated.

Thanks

UPDATE #1:

I've been playing with the FS-UAE settings and think I might have made some progress.

When I change "Video buffer format and color depth" from default 32-bit BGRA to 16-bit, the emulation suddenly flies (all SYS frame-rates now match EMU frame rates even in RTG 1920x1080 mode).

In a 1080 x 1920 RTG screenmode the results now are:

SYS 58, EMU 58

This seems like (partial) solution. However, am I correct in understanding that if I use this setting it will force Amiga RTG screens that are higher than 16-bit (i.e. 32-bit colour) down to 16-bit? This may be detrimental for graphics work (i.e. using ImageFX).

Another note (a bug perhaps). When using 16-bit video buffer format and color depth with "scanlines = 1", any native Amiga chipset modes now just show up as a black screen. Only RTG screenmodes display. Otherwise the emulation does not crash - I can exit even from a black screen by hitting F12. I had to shut off scanlines to see any native chipset Amiga applications.

UPDATE #2

I did a test to see if FS-UAE really takes 32-bit screens and forces them to 16-bit when using this new setting. Yes it does.

For my test I downloaded this 32-bit colour gradient:

http://i.stack.imgur.com/g5Lqc.png

I loaded it first into FS-UAE set to 32-bit BGRA (default) and then from within the Amiga emulation started ImageFX (32-bit RTG screen) and opened the gradient. It looked perfect, without colour banding.

Next I re-started FS-UAE to 16-bit Video buffer format and did the same. This time there was very visible colour banding on the same image when viewed within the emulation.

This is too bad for me as I use ImageFX as a serious graphics application, and mostly work in 32-bit. So I would still be interested in hearing solutions to get FS-UAE to run more speedily in 32-bit video buffer mode.

Note: I did confirm that WinUAE/WinXP does run at full speed in 32-bit colour mode on this same machine, so the hardware can obviously handle 32-bit colour Amiga emulation. It's a problem in either the Lubuntu graphics driver or FS-UAE.

Thanks

[jbl007]

Try:
Video Buffer Format = 32-bit RGBA and
Video Texture Format = RGBA8

Seems to work best on my Intel HD4000.

Originally Posted by ral-clan

When using 16-bit video buffer format and color depth with "scanlines = 1", any native Amiga chipset modes now just show up as a black screen.

Confirmed!

[ral-clan]

Originally Posted by jbl007

Try:
Video Buffer Format = 32-bit RGBA and
Video Texture Format = RGBA8

Seems to work best on my Intel HD4000.

Thanks. I did try your suggested settings and it seems to be a half-way solution. It allows me to use full 32-bit colour screens and performance is better than my original 32-bit setting, but not as perfect as 16-bit.

Under your suggested settings, ImageFX in a 1980 x 1920 RTG screen runs at:

SYS 43.5, EMU 43.5

There is some mouse lag in this high resolution screen, but in lower resolution screens like 1280x720 (my Workbench screen) the mouse seems good. That's some improvement.

I wish I knew exactly what these settings were telling me. I think it means that the emulation is lagging behind real-time (50 or 60fps and so is the host machine?).

[jbl007]

Originally Posted by ral-clan

I wish I knew exactly what these settings were telling me. I think it means that the emulation is lagging behind real-time (50 or 60fps and so is the host machine?).

SYS=System/Video output FPS, EMU=emulation speed (as far as I understand it). So if vsync is disabled (you should disable it) 50/50 is your goal for a PAL Amiga.

[ral-clan]

Originally Posted by jbl007

SYS=System/Video output FPS, EMU=emulation speed (as far as I understand it). So if vsync is disabled (you should disable it) 50/50 is your goal for a PAL Amiga.

How and where do I disable vsync through the GUI (FS-UAE Launcher)?
If not through the GUI then how else?

Thanks.

[jbl007]

Originally Posted by ral-clan

How and where do I disable vsync through the GUI (FS-UAE Launcher)

Settings/Synchronization

[ral-clan]

Originally Posted by jbl007

Settings/Synchronization

Thanks. I guess it was already off by default, as changing these settings didn't make much difference/improvement.