Do You know the situation when on screen in application you have not fully refreshed view? You need to hover the mouse on the object to make it visible/refreshed? Or You need to open close page/screen to refresh all objects?
I have PC-box with Win10. PC has only one DVI port, so extended the screens with USB to DVI adapter (3x VGA2725) and desktop is extended to 4 monitors. Each monitor is used to show the same software (SCADA) 4 different 'windows'. On the screens with adapters there is problem with view/screen refresh, like a 'artefacts' or part of screen not updated. In that situation the page needs to be closed/opened again. The CPU and disk is not overloaded.
Could You help me if above is more software issue or more hardware issue? Shell I look for bad drivers? What shall I check?
EDIT: sorry, missed the fact that the adaptor is multiplying the signal to all monitors.
Nevertheless, check with only one monitor at a time and different combinations to isolate is my suggestion.
PLEASE DISCARD THE FIRST ANSWER BELLOW..
Has the adaptor been tested on one of the other monitors?
If it has been tested on all monitors and the error is only on one
of them, checking that monitor's specs, and the adaptor's specs; to
see if there are any incompatibilities, is probably the best approach.
If no testing on a different monitor has been done, I would definitely
try to isolate the issue by connecting the adaptor to all external
monitors.
If you encounter the same error on a different monitor, we know it is
most likely the adaptor, or it's drivers.
Related
My question is about the delay between calling the present method in DirectX9 and the update appearing on the screen.
On a Windows system, I have a window opened using DirectX9 and update it in a simple way (change the color of the entire window, then call the IDirect3DSwapChain9's present method). I call the swapchain's present method with the flag D3DPRESENT_DONOTWAIT during a vertical blank interval. There is only one buffer associated with the swapchain.
I also obtain an external measurement of when the CRT screen I use actually changes color through a photodiode connected to the center of the screen. I obtain this measurement with sub-millisecond accuracy and delay.
What I found was that the changes appear exactly in the third refresh after the call to present(). Thus, when I call present() at the end of the vertical blank, just before the screen refreshing, the change will appear on the screen exactly 2*screen_duration + 0.5*refresh_duration after the call to present().
My question is a general one:
in how far can I rely on this delay (changes appearing in the third refresh) being the same on different systems ...
... or does it vary with monitors (leaving aside the response times of LCD and LED monitors)
... or with graphics-cards
are there other factors influencing this delay
An additional question:
does anybody know a way of determining, within DirectX9, when a change appeared on the screen (without external measurements)
There's a lot of variables at play here, especially since DirectX 9 itself is legacy and is effectively emulated on modern versions of Windows.
You might want to read Accurately Profiling Direct3D API Calls (Direct3D 9), although that article doesn't directly address presentation.
On Windows Vista or later, once you call Present to flip the front and back buffers, it's passed off to the Desktop Windows Manager for composition and eventual display. There are a lot of factors at play here including GPU vendor, driver version, OS version, Windows settings, 3rd party driver 'value add' features, full-screen vs. windowed mode, etc.
In short: Your Mileage May Vary (YMMV) so don't expect your timings to generalize beyond your immediate setup.
If your application requires knowing exactly when present happens instead of just "best effort" as is more common, I recommend moving to DirectX9Ex, DirectX 11, or DirectX 12 and taking advantage of the DXGI frame statistics.
In case somebody stumbles upon this with a similar question: I found out the reason why my screen update appears exactly on the third refresh after calling present(). As it turns out, the Windows OS by default queues exactly 3 frames before presenting them, and so changes appear on the third refresh. As it stands, this can only be "fixed" by the application starting with Directx10 (and Directx9Ex); for Directx9 and earlier, one has to either use the graphics card driver or the Windows registry to reduce this queueing.
I have a headless Debian ARM machine that I'm running Node on. The device has hard buttons that are mapped to normal keyboard events using gpio-keys.
My goal is to capture the global events from both the hard buttons as well as any attached keyboards in Node. I need a solution that can capture the keydown/keyup events independently of the terminal that it's run in (it will be run over an SSH session). It doesn't have to be cross-platform, as long as it works on ARM Debian I'll accept it.
I am imagining something reading directly from whatever sysfs attributes are necessary, but that's not a requirement.
Can anyone help me on this? I've been stuck for a while.
One of the device files /dev/input/event* will represent the gpio-keys device. You can figure out which one in a number of ways; one easy one is to look at the contents of the uevent file for the device, e.g. /sys/class/input/event0/device/uevent. It'll contain a number of useful key-value properties.
Once you've figured out which device you want, you can open and read from it. It'll return a stream of struct input_events, as defined in <linux/input.h>. These events will correspond to presses and releases for each of your buttons.
You may also want to take a look for existing solutions for at least part of the problem, such as node-keyboard: https://github.com/Bornholm/node-keyboard
This is a fairly broad question, so I will try to keep it as focused as I can.
I currently own a Lenovo laptop with Ubuntu installed and touchscreen functionality and own a pressure-sensitive Bluetooth pen, and been trying to make the two work together as a cheap Cintiq-like tablet.
The pen has, unfortunately, support for only specific apps for iOS phones and tablets.
So after lots of research, I've managed to interface with the pen and create a uinput device for it, so I can register button clicks and pressure changes on the pen and even see them routed to GIMP when configuring the device through the Input Controllers menu.
The code I have so far for that interface is available here.
The trouble starts when trying to test it out with GIMP.
From what I gather, this is because GIMP assumes Wacom devices report their own position, treats touchscreen touches as mouse movements and only allows input from a single device at a time.
My question is, how can I work around this?
More specifically, how can I create a uinput device that would behave as a Wacom tablet and supersede/block the behavior I described?
Or if there's a different solution, such as patching GIMP or writing a plugin for it.
Update (2014-06-07)
The code mentioned above now works.
I have written a blog post on the process of getting this to work: http://gerev.github.io/laptop-cintiq
As you said, Gimp expects you to provide ABS_X and ABS_Y along with ABS_PRESSURE in your driver - which is not strange, because you are using you virtual device as input, so it wouldn't make much sense to pick ABS_X and ABS_Y coordinates from one device and ABS_PRESSURE from another (although they will always be the same in this case). Maybe you can just read the current coordinates of the mouse and copy them as your own device coordinates.
As an example, the project GfxTablet does something similar to what you are trying, they have an Android application for tablets with pen and use uinput to create virtual device that works like pressure-sensitive pen on Linux. I have used it and it worked like a charm in Gimp and mypaint on my laptop, and I had no problem with having a mouse (or the touchpad) active at the same time as the uinput device (I think that Krita added support for generic pressure-sensitive devices recently). You can take a look at the source code of the driver here (surprinsingly simple, to be fair).
Note that this is not a faulty behavior of Gimp, because this is what is expected from a tablet-like device. Take a look at the event codes kernel documentation page, in the last section (Guidelines), it is said that tablets must report ABS_X and ABS_Y. Moreover, they should use BTN_STYLUS and BTN_STYLUS2 to report the tool buttons and some BTN_TOOL_* (e.g. BTN_TOOL_PEN) to report activity (you can find all the available codes in input.h); however, these last does not seem that important, as GfxTablet does not implement them and worked without problem.
I have a touch screen device that is running on windows CE. after 30 second the screen goes off to save power and will come back on it you touch it.
The problem is that randomly when the screen goes off the device will not come back on simply by touching the screen. I have a done a bunch of tests and there is no noticeable pattern to when this happens.
It appears to be performing the same action as when you press the suspend button from the main menu.
I have done some research and found there are 4 power saving settings in the registry and I think I need to disable one to stop the device from "suspending". I never want the device to turn off except for the screen going off, it is always connected to power.
Does anyone know how I can do this or why it is randomly suspending ?
And the entire device is in Chinese So really precise instructions would be appreciated. My application runs on top of the CE.
I know you're after precise instructions, but it's not that simple. The device OEM defined and implemented the power management system for the device, Microsoft only provided the structure for it. The OEM could have implemented power management in any way they sought fit,, and in fact they could have completely ignore the Microsoft-provided framework (wouldn't be the first time an OEM did that). Really you need to get a hold of the OEM and ask them how to prevent the behavior you're seeing or to get something different.
Barring that, you could always play around with the registry entries, but again, there's no guarantee any of them will work. You might look at adjusting power state or the activity timer registry entries.
Playing with the power manager control panel applet might also help (it's probably labelled 电源管理)
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\Timeouts]
"BattSuspend"=dword:0
I want to be able to intercept (and do arbitrary processing on) auto-repeating key presses on Windows. I'd like to know how keyboard auto-repeat is implemented so that I know what options I have. i.e. can I intercept at the:
application,
device driver and/or
hardware level
?
Update: It looks like auto-repeat is (poorly?) generated at the hardware level and then overridden by device drivers (see here).
To modify or filter behavior, you can intercept keys using a hook:
SetWindowsHookEx using WH_KEYBOARD
The hook procedure receives, among others, the repeat count (due to holding down the key)
Note that the low level keyboard hook (WH_KEYBOARD_LL) does not receive the repeat count.
If all your windows are created in the same trhead, you can use a thread-specific hook, and avoid moving the hook procedure to a DLL.
I dimly remember that repeat counts are generated by the keyboard itself and the LL hook sends repeated keydown events - I may be mistaken, though. Under DOS, the key repeat rate and time that was set in BIOS or through a BIOS call did return to default values when a DIN or PS/2 keyboard was unplugged and replugged. I am not sure WHY you need to know exactly.
I suggest that you might want to edit your question... your actual question is "How to suppress auto-repeat on Windows in ${yourLangauge}"...
To which my response is, I haven't got a clue, I've only ever done it in assembler (MASM 80286)... and even then I found a solution on a BBS (does anyone remember them) and just used it. From memory, the intercept has to be done at the device-driver level.
The implementation of autorepeat ($100 says it's assembler) problably won't shed any light on supressing it... that and Microsoft plays those cards very close to it's chest.
Cheers. Keith.
EDIT: I've just thought... techniques may now differ between versions of windows and the plethora of various devices... Oh goodie!
Sounds likes this is "Not programming related", however.
Go to "Accessibility Options" in control panel.
Select "Settings" under "Filter Keys" group, in here, you can switch off repeating keys for that user on that machine.
Hope this is what your looking for.
P.S. Above instructions given for Windows XP.